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https://en.wikipedia.org/wiki/Borassus%20flabellifer
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Borassus flabellifer
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Borassus flabellifer, commonly known as doub palm, palmyra palm, tala or tal palm, toddy palm, lontar palm, wine palm, or ice apple, is a fan palm native to South Asia (especially in Bangladesh, East India, and South India) and Southeast Asia. It is reportedly naturalized in Socotra.
Description
Borassus flabellifer is a robust tree and can reach a height of . The trunk is grey, robust, and ringed with leaf scars; old leaves remain attached to the trunk for several years before falling cleanly. The leaves are fan-shaped, and long, with robust black teeth on the petiole margins. Like all Borassus species, B. flabellifer is dioecious with male and female flowers on separate plants. But very rarely male and female flowers in same trees have also been noticed The male flowers are less than long and form semi-circular clusters, which are hidden beneath scale-like bracts within the catkin-like inflorescences. In contrast, the female flowers are golfball-sized and solitary, sitting upon the surface of the inflorescence axis. After pollination, these blooms develop into fleshy fruits wide, each containing 1-3 seeds. The fruits are black to brown with sweet, fibrous pulp, and each seed is enclosed within a woody endocarp. Young palmyra seedlings grow slowly, producing only a few leaves each year (establishment phase), but at an as yet undetermined time, they grow rapidly, producing a substantial stem.
Uses
Fruit
The fruit (palmyra fruit) measures to in diameter, has a black husk, and is borne in clusters. The top portion of the fruit must be cut off to reveal the sweet jelly seed sockets, translucent pale-white, similar to that of the lychee but with a milder flavor and no pit. The sweet jelly seed sockets occur in combinations of two, three or four seeds inside the fruit. The jelly part of the fruit is covered with a thin, yellowish-brown skin. These are known to contain watery fluid inside the fleshy white body. These seed sockets have been the inspiration behind certain sandeshes called jolbhora (জলভরা) found in Bengal. The soft orange-yellow mesocarp pulp of the ripe fruit is sugary, dense and edible, rich in vitamins A and C. They also contain bitter compound called flabelliferrins, which are steroidal saponins.
The conventional way this fruit is eaten is when the outer casing is still unripe while the seeds are eaten as the fruit. But if the entire fruit is left to ripen, the fibrous outer layer of the palm fruits can also be eaten raw, boiled, or roasted. When this happens, the fruit takes a purple-blackish hue, and tastes similar to coconut flesh. The skin is also eaten as part of the fruit similar to how mango skins are often consumed along with the fruit. Bengalis have perfected the art of making various sweet dishes with the yellowish viscous fluid substance obtained from a ripe palm fruit. These include mustard oil-fried (alternately sunflower oil-fried) taler bora (তালের বড়া) "palmyra vadas" or mixed with thickened milk to prepare tal-khir (তাল ক্ষীর). Thais also use the fruit to make the steamed fluffy tala palm cake, call “Khanom Tan”.
In northern India, the fruit is known as Taad Gola in Hindi-Urdu (ताड़ गोला / ). In Kerala it is called nonku (നൊങ്ക്) whereas in Tamil Nadu, it is called nungu (நுங்கு). In Odisha, it is called tala (ତାଳ). Ice apple in Indonesia is called buah lontar or siwalan. In Karnataka it is called "Taati Nungu"(ತಾಟಿ ನುಂಗು / ತಾಟಿ ನಿಂಗು). In Myanmar, it is called htan-thee (ထန်းသီး). In Telangana and Andhra Pradesh, this fruit is called as "Thaati Munjalu" (తాటి ముంజలు). In Tulu language of Coastal Karnataka it is called “Erolu”(ಇರೋಲು).
Sap
Obtaining the sap traditionally involves tapping the top shoots and collecting the dripping juice in hanging earthen pots (in some regions a plastic or bamboo bottle). The juice collected in evening or after fermentation becomes sour, and is called tāḍī (ताडी > "toddy") in Marathi, hta-yay (ထန်းရည်) in Myanmar and Bhojpuri. This sap was the main source of sugar production in Thailand before sugarcane was introduced, as can be seen in the Thai word for sugar (), which literally means the water of the tala palm.
A sugary sap can be obtained from the young inflorescence, either male or female and it is concentrated to a crude sugar called jaggery or Tal Patali (তাল পাটালী) in Bengali, hta-nyat (ထန်းလျက်) in Myanmar and Pana Vellam or Karuppukatti (கருப்புகட்டி or கருபட்டி) in Tamil, or it can be fermented to make an alcoholic beverage called toddy or htan-yay hkar (ထန်းရည်ခါး) in Myanmar, or distilled to make a liqour arrack. The concentrated raw sugar obtained from palms is called Gula Jawa (Javanese sugar) in Indonesia, and is widely used in Javanese cuisine. In Thailand, it is called nam tan pik (น้ำตาลปึก), referring to the pack of sugar obtained from drying the palm sap, though in the modern day nam tan pik is often made from coconut water because the convenient of farming and harvesting.
In Thailand, there are techniques that utilize the anti-bacterial agents of some woods to keep the sap from becoming sour while tapping. After sterilization, the sap is available as a beverage called nam tan sod (น้ำตาลสด, ) or used to make an alcoholic beverage called nam tan mao (น้ำตาลเมา ). “Nam tan”, literally means tala palm water, later acquired the meaning of “sugar “.
Sprouts
In the Indian states of Tamil Nadu, Andhra Pradesh, Telangana and Bihar, and in Jaffna, Bengal, Sri Lanka, the seeds are planted and made to germinate and the fleshy stems (below the surface) are boiled or roasted and eaten. It is very fibrous and nutritious. It is known as Thegalu (తేగలు) or Gaygulu (గేగులు) or Gengulu (గెంగులు) (especially in Telangana) in Telugu, as Panai Kizhangu or Panangkizhangu (பனங்கிழங்கு) in Tamil, and as htabin myiq (ထန်းပင်မြစ်) in Myanmar.
The germinated seed's hard shell is also cut open to take out the crunchy kernel, which tastes like a sweeter water chestnut. It is called "Taal-Anti" (তাল আঁটি) in Bengali,
"Sachi-Htway" (ဆံချည်ထွေး) in Myanmar, "Buragunju" (బురగుంజు) in Telugu and "Thava nai" in Tamil.
The white kernel of the ripe palm fruit after being left for a few months is used as an offering in Lakshmi Puja in various parts of Bengal and is also eaten raw.
In Thai cuisine, it is used as an ingredient to a type of curry, called “Kaeng Hua Tan”.
Leaves
The Borassus flabellifer leaves are used for thatching, mats, baskets, fans, hats, umbrellas, and as writing material.
All the literature of the old Tamil was written in preserved palm leaves also known as Palm-leaf manuscript. In Tamil Yaedu or Olai chuvadi. Most of the ancient literature in Telugu are written on palm leaves (Tala patra grandhas).
In Indonesia the leaves were used in the ancient culture as paper, known as "lontar" (from Old/Modern Javanese ron tal "tal leaves") Leaves of suitable size, shape, texture, and maturity were chosen and then seasoned by boiling in salt water with turmeric powder, as a preservative. The leaves were then dried. When they were dry enough, the face of the leaf was polished with pumice, cut into the proper size, and a hole made in one corner. Each leaf made four pages. The writing was done with a stylus and had a very cursive and interconnected style. The tal is so closely related to regional manuscript culture that a tal frond is immortalized as the part of the logo for the Dewan Bahasa dan Pustaka, Malaysia's language regulatory board designed in 1957 by Hussien Enas.
The stem of the leaves has thorny edges (called "karukku" in Tamil).
The skin of the stem can be peeled off and be used as rope and also used to weave into cots (நார்க்கட்டில் in Tamil). In some part of Tamil Nadu, a variety of rice flour cake (called "Kozhukattai") is prepared using the leaf.
In the eastern part of India, the leaves are used to make hand fans. In Myanmar, the leaves are used to make hand fans for the Buddhist monks and are called "Yap" (ယပ်).
Trunk
The stalks are used to make fences and also produce a strong, wiry fiber suitable for cordage and brushes. The black timber is hard, heavy, and durable and is highly valued for construction. It is superior to coconut timber, or red palm.
Crown
When the crown of the tree is removed, the segment from which the leaves grow out is an edible cake. This is called htan-ohn-hnauk (ထန်းဦးဏှောက်) in Myanmar, pananchoru (பனஞ்சோறு) in Tamil or thati adda (తాటి అడ్డ/తాటి మట్ట) in Telugu.
Roots
In Cambodia, where the palm is known as thnôt''' (Khmer), the roots are dried and smoked to heal nasal complaints.
CultivationBorassus flabellifer has a growth pattern, very large size, and clean habits that make it an attractive ornamental tree, cultivated for planting in gardens and parks as landscape palm species.
Cultural symbolism
The palmyra tree is the official tree of Tamil Nadu. Highly respected in Tamil culture, it is called "katpaha tharu" ("celestial tree") because all its parts have a use. Panaiveriyamman, named after panai, the Tamil name for the Palmyra palm, is an ancient tree deity related to fertility linked to this palm. This deity is also known as Taalavaasini, a name that further relates her to all types of palms.
The Asian palmyra palm is a symbol of Cambodia where it is a very common palm, found all over the country. It also grows near the Angkor Wat temple.
In Indonesia the Palmyra tree is the symbol of South Sulawesi province.
This plant has captured the imagination of Bengalis, especially in the words of Rabindranth Tagore whose nursery rhyme 'Tal Gach ek Paye dariye' (তাল গাছ এক পায়ে দাড়িয়ে.., literally Palmyra tree standing on a single leg ... ) in Sahaj Path (সহজ পাঠ) is a staple reading material in schools in Bangladesh and West Bengal.
In the Hindu epic Mahabharata'', a palmyra tree is the chariot-banner of Bheeshma and Balarama.
In Myanmar, the tree is the symbol of Anyar (အညာ) (the dry zone of Myanmar), and is called "pa-de-thar-pin" (ပဒေသာပင်) meaning the tree from which anything you wish can be taken. There are many poems and traditional sounds related to this tree.
Sunthorn Phu, Thailand’s eminent bard of the Early Bangkok Era, mentioned the plant in many of his poems.
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Biology and health sciences
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Arecales (inc. Palms)
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Plants
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13163733
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https://en.wikipedia.org/wiki/Stenotherm
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Stenotherm
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A stenotherm (from Greek στενός stenos "narrow" and θέρμη therme "heat") is a species or living organism capable of surviving only within a narrow temperature range. This specialization is often found in organisms that inhabit environments with relatively stable environments, such as deep sea environments or polar regions.
The opposite of a stenotherm is a eurytherm, an organism that can function across a wide range of body temperatures. Eurythermic organisms are typically found in environments with significant temperature variations, such as temperate or tropical regions.
The size, shape, and composition of an organism's body can influence its temperature regulation, with larger organisms generally maintaining a more stable internal temperature than smaller ones.
Examples
Chionoecetes opilio is a stenothermic organism, and temperature significantly affects its biology throughout its life history, from embryo to adult. Small changes in temperature (< 2 °C) can increase the duration of egg incubation for C. opilio by a full year.
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Biology and health sciences
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Basics
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Biology
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14329297
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https://en.wikipedia.org/wiki/Climate%20change%20in%20Australia
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Climate change in Australia
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Climate change has been a critical issue in Australia since the beginning of the 21st century. Australia is becoming hotter and more prone to extreme heat, bushfires, droughts, floods, and longer fire seasons because of climate change. Climate issues include wildfires, heatwaves, cyclones, rising sea levels, and erosion.
Since the beginning of the 20th century, Australia has experienced an increase of over 1.5 °C in average annual temperatures, with warming occurring at twice the rate over the past 50 years compared with the previous 50 years. Recent climate events such as extremely high temperatures and widespread drought have focused government and public attention on the effects of climate change in Australia. Rainfall in southwestern Australia has decreased by 10–20% since the 1970s, while southeastern Australia has also experienced a moderate decline since the 1990s. Rainfall is expected to become heavier and more infrequent, as well as more common in summer rather than in winter. Australia's annual average temperatures are projected to increase 0.4–2.0 °C above 1990 levels by the year 2030, and 1–6 °C by 2070. Average precipitation in the southwest and southeast Australia is projected to decline during this time, while regions such as the northwest may experience increases in rainfall.
Climate change is affecting the continent's environment and ecosystems. Australia is vulnerable to the effects of global warming projected for the next 50 to 100 years because of its extensive arid and semi-arid areas, and already warm climate, high annual rainfall variability. The continent's high fire risk increases this susceptibility to changes in temperature and climate. Meanwhile, Australia's coastlines will experience erosion and inundation from an estimated increase in global sea level. Australia's unique ecosystems such as the Great Barrier Reef and many animal species are also at risk.
Climate change also has diverse implications for Australia's economy, it's agriculture and public health. Projected impacts include more severe floods, droughts, and cyclones. Furthermore, Australia's population is highly concentrated in coastal areas at risk from rising sea levels, and existing pressures on water supply will be exacerbated. The exposure of Indigenous Australians to climate change impacts is exacerbated by existing socio-economic disadvantages which are linked to colonial and post-colonial marginalisation. The communities most affected by climate changes are those in the North where Aboriginal and Torres Strait Islander people make up 30% of the population. Aboriginal and Torres Strait Islander communities located in the coastal north are the most disadvantaged due to social and economic issues and their reliance on traditional land for food, culture, and health. This has raised the question for many community members in these areas, "Should we stay or move away?"
Australia is also a contributor to climate change, with its greenhouse gas emissions per capita above the world average. The country is highly reliant on coal and other fossil fuels, although renewable energy coverage is increasing. National climate change mitigation efforts include a commitment to achieving net zero emissions by 2050 under the Paris Agreement, although Australia has repeatedly ranked poorly in the Climate Change Performance Index and other international rankings for its climate targets and implementation. Climate change adaptation can be performed at national and local levels and was identified as a priority for Australia in the 2007 Garnaut Review.
Climate change has been a divisive or politicised issue in Australian politics since the 2000s, contributing to successive governments implementing and repealing mitigation policies such as carbon pricing. Some Australian media outlets have promoted climate misinformation. The issue has sparked protests in support of climate change policies, including some of the largest demonstrations in Australia's history.
Greenhouse gas emissions
Impacts on the natural environment
Temperature and weather changes
Australia's instrumental record from 1885 to the present shows the following broad picture:
Conditions from 1885 to 1898 were generally fairly wet, though less so than in the period since 1968. The only noticeably dry years in this era were 1888 and 1897. Although some coral core data suggest that 1887 and 1890 were, with 1974, the wettest years across the continent since settlement, rainfall data for Alice Springs, then the only major station covering the interior of the Northern Territory and Western Australia, strongly suggest that 1887 and 1890 were overall not as wet as 1974 or even 2000. In New South Wales and Queensland, however, the years 1886–1887 and 1889–1894 were indeed exceptionally wet. The heavy rainfall over this period has been linked with a major expansion of the sheep population and February 1893 saw the disastrous 1893 Brisbane flood.
A drying of the climate took place from 1899 to 1921, though with some interruptions from wet El Niño years, especially between 1915 and early 1918 and in 1920–1921, when the wheat belt of the southern interior was drenched by its heaviest winter rains on record. Two major El Niño events in 1902 and 1905 produced the two driest years across the whole continent, whilst 1919 was similarly dry in the eastern States apart from the Gippsland.
The period from 1922 to 1938 was exceptionally dry, with only 1930 having Australia-wide rainfall above the long-term mean and the Australia-wide average rainfall for these seventeen years being 15 to 20 per cent below that for other periods since 1885. This dry period is attributed in some sources to a weakening of the Southern Oscillation and in others to reduced sea surface temperatures. Temperatures in these three periods were generally cooler than they are currently, with 1925 having the coolest minima of any year since 1910. However, the dry years of the 1920s and 1930s were also often quite warm, with 1928 and 1938 having particularly high maxima.
The period from 1939 to 1967 began with an increase in rainfall: 1939, 1941 and 1942 were the first close-together group of relatively wet years since 1921. From 1943 to 1946, generally dry conditions returned, and the two decades from 1947 saw fluctuating rainfall. 1950, 1955 and 1956 were exceptionally wet except 1950 and 1956 over arid and wheatbelt regions of Western Australia. 1950 saw extraordinary rains in central New South Wales and most of Queensland: Dubbo's 1950 rainfall of can be estimated to have a return period of between 350 and 400 years, whilst Lake Eyre filled for the first time in thirty years. In contrast, 1951, 1961 and 1965 were very dry, with complete monsoon failure in 1951/1952 and extreme drought in the interior during 1961 and 1965. Temperatures over this period initially fell to their lowest levels of the 20th century, with 1949 and 1956 being particularly cool, but then began a rising trend that has continued with few interruptions to the present.
Since 1968, Australia's rainfall has been 15 per cent higher than between 1885 and 1967. The wettest periods have been from 1973 to 1975 and 1998 to 2001, which comprise seven of the thirteen wettest years over the continent since 1885. Overnight minimum temperatures, especially in winter, have been markedly higher than before the 1960s, with 1973, 1980, 1988, 1991, 1998 and 2005 outstanding in this respect. There has been a marked decrease in the frequency of frost across Australia.
According to the Bureau of Meteorology, Australia's annual mean temperature for 2009 was 0.9 °C above the 1961–90 average, making it the nation's second-warmest year since high-quality records began in 1910.
According to the Bureau of Meteorology's 2011 Australian Climate Statement, Australia had lower than average temperatures in 2011 as a consequence of a La Niña weather pattern; however, "the country's 10-year average continues to demonstrate the rising trend in temperatures, with 2002–2011 likely to rank in the top two warmest 10-year periods on record for Australia, at above the long-term average". Furthermore, 2014 was Australia's third warmest year since national temperature observations commenced in 1910.
Sea level rise
The Australian Government released a report saying that up to 247,600 houses are at risk from flooding from a sea level rise of 1.1 metres. There were 39,000 buildings located within 110 metres of 'soft' erodible shorelines, at risk from a faster erosion due to sea level rise. Adaptive responses to this specific climate change threat are often incorporated in the coastal planning policies and recommendations at the state level. For instance, the Western Australia State Coastal Planning Policy established a sea level rise benchmark for initiatives that address the problem over a 100-year period. Lower projections indicate that sea levels will rise by 40 to 90 cm upon the end of the century
Water (droughts and floods)
Bureau of Meteorology records since the 1860s show that a 'severe' drought has occurred in Australia, on average, once every 18 years. Australia is already the driest populated continent in the world.
Rainfall in southwestern Australia has decreased by 10–20% since the 1970s, while southeastern Australia has also experienced a moderate decline since the 1990s. Rainfall is expected to become heavier and more infrequent, as well as more common in summer rather than in winter.
In June 2008 it became known that an expert panel had warned of long-term, maybe irreversible, severe ecological damage for the whole Murray-Darling basin if it did not receive sufficient water by October of that year. Water restrictions were in place in many regions and cities of Australia in response to chronic shortages resulting from the 2008 drought. In 2004 paleontologist Tim Flannery predicted that unless it made drastic changes the city of Perth, Western Australia, could become the world's first ghost metropolis—an abandoned city with no more water to sustain its population.
In 2019 the Drought and Water Resources Minister of Australia David Littleproud, said, that he "totally accepts" the link between climate change and drought in Australia because he "lives it". He called for a reduction in greenhouse gas emission and massive installation of renewable energy. Former leader of the Nationals Barnaby Joyce said that if the drought became more fierce and dams were not built, the Coalition risks "political annihilation".
According to the 2022 IPCC report, there has been an increase in flooding episodes and other catastrophic weather events because of global warming. These unusual weather changes in include rainfall in the north and severe droughts in the south. Less rainfall means less streamflow of water for major cities. The IPCC recommends a step up to our adaptation and finance policies in our systems to keep up with the drastic impacts of climate change for a sustainable development.
Water resources
Healthy and diverse vegetation is essential to river health and quality, and many of Australia's most important catchments are covered by native forest, maintaining a healthy ecosystem. Climate change will affect growth, species composition and pest incursion of native species and in turn, will profoundly affect water supply from these catchments. Increased re-afforestation in cleared catchments also has the prospect for water losses.
Between 1970 and 2024, 28% of Australia's Hydrological Reference Stations showed a significant decrease in streamflow while 4% showed a significant increase. The stations with increases were all in northern Australia while those with decreases were largely in southern Australia.
The CSIRO predicted that the additional effects in Australia of a temperature rise of between only 1 and 2 °C will be:
12–25% reduction inflow in the Murray River and Darling River basin.
7–35% reduction in Melbourne's water supply.
Bushfires
There is an increase in fire activity in Australia since 1950. The causes include "more dangerous fire weather conditions, increased risk factors associated with pyroconvection, including fire-generated thunderstorms, and increased ignitions from dry lightning, all associated to varying degrees with anthropogenic climate change".
Firefighting officials are concerned that the effects of climate change will increase the frequency and intensity of bushfires under even a "low global warming" scenario. A 2006 report, prepared by CSIRO Marine and Atmospheric Research, Bushfire CRC, and the Australian Bureau of Meteorology, identified South Eastern Australia as one of the three most fire-prone areas in the world, and concluded that an increase in fire-weather risk is likely at most sites over the next several decades, including the average number of days when the McArthur Forest Fire Danger Index rating is very high or extreme. It also found that the combined frequencies of days with very high and extreme FFDI ratings are likely to increase 4–25% by 2020 and 15–70% by 2050, and that the increase in fire-weather risk is generally largest inland.
Former Australian Greens leader, Bob Brown said that the fires were "a sobering reminder of the need for this nation and the whole world to act and put at a priority the need to tackle climate change". The Black Saturday Royal Commission recommended that "the amount of fuel-reduction burning done on public land each year should be more than doubled".
In 2018, the fire season in Australia began in the winter. August 2018 was hotter and windier than the average. Those meteorological conditions led to a drought in New South Wales. The Government of the state already gave more than $1 billion to help the farmers. The hotter and drier climate led to more fires. The fire seasons in Australia are lengthening and fire events became more frequent in the latest 30 years. These trends are probably linked to climate change.
The 2019–20 Australian bushfire season was by some measures Australia's "worst bushfire season on record". In New South Wales, the fires burnt through more land than any other blazes in the past 25 years, in addition to being the state's worst bushfire season on record. NSW also experienced the longest continuously burning bushfire complex in Australia's history, having burnt more than , with flames being reported. Approximately 3 billion animals were killed or displaced by the bushfires and this made them one of the worst natural disasters in recorded history. The chance of reaching the climatic conditions that fuels the fires became more than four times bigger since the year 1900 and will become eight times more likely to occur if the temperature will rise by 2 degrees from the preindustrial level. In December 2019 the New South Wales Government declared a state of emergency after record-breaking temperatures and prolonged drought exacerbated the bushfires.
In 2019 bushfires linked to climate change created air pollution 11 times higher that the hazardous level in many areas of New South Wales. Many medical groups called to protect people from "public health emergency" and moving on from fossil fuels.
According to the United Nations Environment Programme the megafires in Australia in 2019–2020 are probably linked to climate change that created the unusually dry and hot weather conditions. This is part of a global trend. Brazil, the United States, the Russian Federation, and the Democratic Republic of the Congo all face similar problems. By the second week of January the fires burned a territory of approximately 100,000 square kilometres close to the territory of England, killed one billion animals and caused large economic damage.
Researchers claim that the exceptionally strong wildfires in 2019–2020 were impossible without the effects of climate change. More than one-fifth of Australian forests were burned in one season, which was completely unprecedented. They say that: "In the case of recent events in Australia, there is no doubt that the record temperatures of the past year would not be possible without anthropogenic influence, and that under a scenario where emissions continue to grow, such a year would be average by 2040 and exceptionally cool by 2060." Climate change probably also caused drier weather conditions in Australia by impacting Indian Ocean Dipole, which also increase fires. In average, below 2% of Australian forests burn annually. Climate change has increased the likelihood of the wildfires in 2019–2020 by at least 30%, but researchers said the result is probably conservative.
Extreme weather events
Rainfall patterns and the degree of droughts and storms brought about by extreme weather conditions are likely to be affected. The CSIRO predicts that a temperature rise of between 2 and 3 °C on the Australian continent could incur some of the following extreme weather occurrences, in addition to standard patterns:
Wind speeds of tropical cyclones could intensify by 5 to 10%.
In 100 years, strong tides would increase by 12–16% along eastern Victoria's coast.
The forest fire danger indices in New South Wales and Western Australia would grow by 10% and the forest fire danger indices in south, central and north-east Australia would increase by more than 10%.
Heatwaves
A report in 2014 revealed that, due to the change in climatic patterns, heat waves were found to be increasingly more frequent and severe, with an earlier start to the season and longer duration.
Since temperatures began to be recorded in 1910, they have increased by an average of 1 °C, with most of this change occurring from 1950 onwards. This period has seen the frequency and intensity of extreme heat events increase.
Summer 2013–14 was warmer than average for the entirety of Australia. Both Victoria and South Australia saw record-breaking temperatures. Adelaide recorded a total of 13 days reaching 40 °C or more, 11 of which reached 42 °C or more, as well as its fifth-hottest day on record—45.1 °C on 14 January. The number of days over 40 °C beat the previous record of summer 1897–1898, when 11 days above 40 °C were recorded. Melbourne recorded six days over 40 °C, while nighttime temperatures were much warmer than usual, with some nights failing to drop below 30 °C. Overall, the summer of 2013–2014 was the third-hottest on record for Victoria, fifth-warmest on record for New South Wales, and sixth-warmest on record for South Australia. This heatwave has been directly linked to climate change, which is unusual for specific weather events.
Following the 2014 event, it was predicted that temperatures might increase by up to 1.5 °C by 2030.
2015 was Australia's fifth-hottest year on record, continuing the trend of record-breaking high temperatures across the country. According to Australian Climate Council in 2017 Australia had its warmest winter on record, in terms of average maximum temperatures, reaching nearly 2 °C above average. January 2019 was the hottest month ever in Australia with average temperatures exceeding .
Ecosystems and biodiversity
Sustained climate change could have drastic effects on the ecosystems of Australia. For example, rising ocean temperatures and continual erosion of the coasts from higher water levels will cause further bleaching of the Great Barrier Reef. Beyond that, Australia's climate will become even harsher, with more powerful tropical cyclones and longer droughts.
The Department of Climate Change said in its Climate Change Impacts and Costs fact sheet: "...ecologically rich sites, such as the Great Barrier Reef, Queensland Wet Tropics, Kakadu Wetlands, Australian Alpine areas, south-western Australia and sub- Antarctic islands are all at risk, with significant loss of biodiversity projected to occur by 2020". It also said: "Very conservatively, 90 Australian animal species have so far been identified at risk from climate change, including mammals, insects, birds, reptiles, fish, and amphibians from all parts of Australia."
Australia has some of the world's most diverse ecosystems and natural habitats, and it may be this variety that makes them the Earth's most fragile and at-risk when exposed to climate change. The Great Barrier Reef is a prime example. Over the past 20 years it has experienced unparalleled rates of bleaching. Additional warming of 1 °C is expected to cause substantial losses of species and of associated coral communities.
The CSIRO predicts that the additional results in Australia of a temperature rise of between 2 and 3 °C will be:
97% of the Great Barrier Reef bleached annually.
10–40% loss of principal habitat for Victoria and montane tropical vertebrate species.
92% decrease in butterfly species' primary habitats.
98% reduction in Bowerbird habitat in Northern Australia.
80% loss of freshwater wetlands in Kakadu (30 cm sea level rise).
A study conducted in 2024, suggests that worsening climate scenarios may have significant impacts on the habitat area for vertebrates and vascular plant species in Australia. This data suggests that in 2030, the habitat area among species appears consistent across climate scenarios, however, by 2090, a significant change is predicted, as deteriorating climate conditions are associated with reductions in habitat area for biodiversity.
Great Barrier Reef
The Great Barrier Reef could be killed as a result of the rise in water temperature forecast by the IPCC. A UNESCO World Heritage Site, the reef has experienced unprecedented rates of bleaching over the past two decades, and additional warming of only 1 °C is anticipated to cause considerable losses or contractions of species associated with coral communities.
Lord Howe Island
The coral reefs of the World Heritage-listed Lord Howe Island could be killed as a result of the rise in water temperature forecast by the IPCC.
As of April 2019, approximately 5% of the coral is dead.
Impacts on people
Economic impacts
According to the Climate Commission (now the Climate Council) report in 2013, the extreme heatwaves, flooding and bushfires striking Australia have been intensified by climate change and will get worse in future in terms of their impacts on people, property, communities and the environment. The summer of 2012/2013 included the hottest summer, hottest month and hottest day on record. The cost of the 2009 bushfires in Victoria was estimated at A$4.4bn (£3bn) and the Queensland floods of 2010/2011 cost over A$5bn.
In 2008 the Treasurer and the Minister for Climate Change and Water released a report that concluded the economy will grow with an emissions trading scheme in place.
A report released in October 2009 by the Standing Committee on Climate Change, Water, Environment and the Arts, studying the effects of a 1-metre sea level rise, quite possible within the next 30–60 years, concluded that around 700,000 properties around Australia, including 80,000 buildings, would be inundated, the collective value of these properties is estimated at $155 billion.
In 2019 the Australian Bureau of Agricultural and Resource Economics and Sciences published a report about the impact of climate change on the profitability of the Australian agriculture, saying that the profit of the Australian farms was cut by 22% due to climate change in the years 2000–2019.
According to the 2022 IPCC report Australia will lose billions of dollars due to loss of life, and physical damages. These natural disasters are caused by climate change and increasing global warming will worsen these events. The report estimates that under 2 degrees of warming Australia will lose $115 billion in the next decade, and $350 billion in the next twenty years. If warming goes up to under 3 degrees of warming Australia's economy will lose $200 billion and $600 billion by 2042.
Agriculture forestry and livestock
Small changes caused by global warming, such as a longer growing season, a more temperate climate and increased concentrations, may benefit Australian crop agriculture and forestry in the short term. However, such benefits are unlikely to be sustained with increasingly severe effects of global warming. Changes in precipitation and consequent water management problems will further exacerbate Australia's current water availability and quality challenges, both for commercial and residential use.
The CSIRO predicts that the additional results in Australia of a temperature rise of between 3 and 4 °C will be:
32% possibility of diminished wheat production (without adaptation).
45% probability of wheat crop value being beneath present levels (without adaptation).
55% of primary habitat lost for Eucalyptus.
25–50% rise in common timber yield in cool and wet parts of South Australia.
25–50% reduction in common timber yield in North Queensland and the Top End.
6% decrease in Australian net primary production (for 20% precipitation decrease)
128% increase in tick-associated losses in net cattle production weight.
Electricity demand
Use of domestic air conditioners during severe heatwaves can double electricity demand, placing great stress on electricity generation and transmission networks, and lead to load shedding. In addition, bushfires can damage electricity lines, while repairing power poles and power line damages is often restricted during hot and dry weather because of high fire risks.
Impacts on housing
Settlements and infrastructure
Global warming could lead to substantial alterations in climate extremes, such as tropical cyclones, heat waves and severe precipitation events. This would degrade infrastructure and raise costs through intensified energy demands, maintenance for damaged transportation infrastructure, and disasters, such as coastal flooding. In the coastal zone, sea level rise and storm surge may be more critical drivers of these changes than either temperature or precipitation.
The CSIRO describes the additional impact on settlements and infrastructure for rises in temperature of only 1 to 2 °C: A 22% rise in 100-year storm surge height around Cairns; as a result, the area flooded doubles.
Human settlements
Climate change will have a higher impact on Australia's coastal communities, due to the concentration of population, commerce and industry. Climate modelling suggests that a temperature rise of 1–2 °C will result in more intense storm winds, including those from tropical cyclones. Combine this with sea level rise, and the result is greater flooding, due to higher levels of storm surge and wind speed. The impact of climate change on insurance against catastrophes. Proceedings of Living with Climate Change Conference. Canberra, 19 December.) Tourism of coastal areas may also be affected by coastal inundation and beach erosion, as a result of sea level rise and storm events. At higher levels of warming, coastal impacts become more severe with higher storm winds and sea levels.
Property
A report released in October 2009 by the Standing Committee on Climate Change, Water, Environment and the arts, studying the effects of a 1-metre sea level rise, possible within the next 30–60 years, concluded that around 700,000 properties around Australia, including 80,000 buildings, would be inundated. The collective value of these properties is estimated at $150 billion.
A 1-metre sea level rise would have massive impacts, not just on property and associated economic systems, but in displacement of human populations throughout the continent. Queensland is the state most at risk due to the presence of valuable beachfront housing.
Impacts on foreign policy and national security
Several prominent reports and decision makers are concerned that climate change affects Australia’s national security. A 2023 assessment of the Australian Office of National Intelligence on the security implications of climate change (commissioned by Anthony Albanese) remains classified. These concerns are tied to broader debates about climate security.
Climate change is unlikely to trigger large-scale migration movements to Australia. Research shows that people adversely affected by climate change often lack the resources to migrate over large distances (they are adapt in-situ or move to nearby places). This is particularly the case for Australia, which is an island nation with tough border controls and immigration policies.
Climate change can cause major challenges to Australia’s foreign policies. Pacific Island countries, which are highly vulnerable to climate change, have repeatedly blamed Australia for not being active enough in mitigating climate change. With geopolitical tensions between Australia and China on the rise, these countries are of high relevance for the Australian government. In addition, existing data suggest that several countries in Australia’s neighbourhood (e.g., Indonesia, the Philippines, large parts of South Asia) and some key partner governments (e.g., India, Papua New Guinea) are very vulnerable to climate-related unrest and conflict.
Several reports also warn that climate change poses significant challenges to the capacities of the Australian Defence Force. Many military bases are located close to the coastline, which is threatened by sea-level rise and more intense storms. Civilian infrastructure relevant to military operations (like transports networks and power lines) is also adversely affected by climate change, for instance when floods wash away key supply roads. More extreme heat days complicate military training and put a heavier toll on equipment, particularly in northern Australia. Finally, the Australian Defence Force will be called upon more often to provide disaster relief within the country and internationally, further straining its resources.
Health impacts
The CSIRO predicts that the additional results in Australia of a temperature rise of between only 1 and 2 °C will be:
Southward spread of malaria receptive zones.
Risk of dengue fever among Australians increases from 170,000 people to 0.75–1.6 million.
10% increase in diarrhoeal diseases among Aboriginal children in central Australia.
100% increase in a number of people exposed to flooding in Australia.
Increased influx of refugees from the Pacific Islands.
Based on some predictions for 2070, data suggests that people who are not accustomed to the warmer climate may experience as much as 45 days per year where they are unable to tolerate being outside, compared to the current 4–6 days per year.
Impacts on indigenous Australians
Indigenous Australians have a millennia long history of responding and adapting to social and environmental changes. Indigenous Australians have a high level of situated traditional knowledge and historical knowledge about climate change. However, the exposure of Indigenous Australians to climate change impacts is exacerbated by existing socio-economic disadvantages which are linked to colonial and post-colonial marginalisation.
Some of these changes include a rise in sea levels, getting hotter and for a longer period of time, and more severe cyclones during the cyclone season. Climate issues include wild fires, heatwaves, floods, cyclones, rising sea levels, rising temperatures, and erosion. The communities most affected by climate changes are those in the North where Aboriginal and Torres Strait Islander people make up 30% of the population. Aboriginal Australians and Torres Strait Islander communities located in the coastal north are the most disadvantaged due to social and economic issues and their reliance on traditional land for food, culture, and health. This has begged the question for many community members in these regions, should they move away from this area or remain present.
Many Aboriginal people live in rural and remote agricultural areas across Australia, especially in the Northern and Southern areas of the continent. There are a variety of different climate impacts on different Aboriginal communities which includes cyclones in the Northern region and flooding in Central Australia which negatively impacts cultural sites and therefore the relationship between indigenous people and the places that hold their traditional knowledge. Other effects include sea level rise, loss of land and hunting ground, changes in fire regimes, increased severity and duration of wet and dry seasons as well as reduced numbers of animals in the sea, rivers and creeks.
Vulnerability
The vulnerability comes from remote location where indigenous groups live, lower socio-economic status, and reliance of natural systems for economic needs. Disadvantages which are compounding Indigenous peoples vulnerability to climate change include inadequate health and educational services, limited employment opportunities as well as insufficient infrastructure. Top down institutions have also restricted Indigenous Australians ability to contribute to climate policy frameworks and have their culture and practices recognised.
Many of the economic, political, and social-ecological issues present in indigenous communities are long term effects from colonialism and the continued marginalization of these communities. These issues are aggravated by climate change and environmental changes in their respective regions. Indigenous people are seen as particularly vulnerable to climate change because they already live in poverty, poor housing and have poor educational and health services, other socio-political factors place them at risk for climate change impacts. Indigenous people have been portrayed as victims and as vulnerable populations for many years by the media. Aboriginal Australians believe that they have always been able to adapt to climate changes in their geographic areas.
Many communities have argued for more community input into strategies and ways to adapt to climate issues instead of top down approaches to combating issues surrounding environmental change. This includes self-determination and agency when deciding how to respond to climate change including proactive actions. Indigenous people have also commented on the need to maintain their physical and mental well-being in order to adapt to climate change which can be helped through the kinship relationships between community members and the land they occupy.
In Australia, Aboriginal people have argued that in order for the government to combat climate change, their voices must be included in policy making and governance over traditional land. Much of the government and institutional policies related to climate change and environmental issues in Australia has been done so through a top down approach. Indigenous communities have stated that this limits and ignores Aboriginal Australian voices and approaches. Due to traditional knowledge held by these communities and elders within those communities, traditional ecological knowledge and frameworks are necessary to combat these and a variety of different environmental issues.
Heat and drought
Fires and droughts in Australia, including the Northern regions, occur mostly in savannas because of current environmental changes in the region. The majority of the fire prone areas in the savanna region are owned by Aboriginal Australian communities, the traditional stewards of the land. Aboriginal Australians have traditional landscape management methods including burning and clearing the savanna areas which are the most susceptible to fires. Traditional landscape management declined in the 19th century as Western landscape management took over. Today, traditional landscape management has been revitalized by Aboriginal Australians, including elders. This traditional landscape practices include the use of clearing and burning to get rid of old growth. Though the way in which indigenous communities in this region manage the landscape has been banned, Aboriginal Australian communities who use these traditional methods actually help in reducing greenhouse gas emissions.
Impact of climate change on health
Increased temperatures, wildfires, and drought are major issues in regard to the health of Aboriginal Australian communities. Heat poses a major risk to elderly members of communities in the North. This includes issues such as heat stroke and heat exhaustion. Many of the rural indigenous communities have faced thermal stress and increased issues surrounding access to water resources and ecological landscapes. This impacts the relationship between Aboriginal Australians and biodiversity, as well as impacts social and cultural aspects of society.
Aboriginal Australians who live in isolated and remote traditional territories are more sensitive than non-indigenous Australians to changes that effect the ecosystems they are a part of. This is in large part due to the connection that exists between their health (including physical and mental), the health of their land, and the continued practice of traditional cultural customs. Aboriginal Australians have a unique and important relationship with the traditional land of their ancestors. Because of this connection, the dangerous consequences of climate change in Australia has resulted in a decline in health including mental health among an already vulnerable population. In order to combat health disparities among these populations, community based projects and culturally relevant mental and physical health programs are necessary and should include community members when running these programs.
Traditional knowledge
Indigenous people have always responded and adapted to climate change, including indigenous people of Australia. Aboriginal Australian people have existed in Australia for tens of thousands of years. Due to this continual habitation, Aboriginal Australians have observed and adapted to climatic and environmental changes for millennia which uniquely positions them to be able to respond to current climate changes. Though these communities have shifted and changed their practices overtime, traditional ecological knowledge exists that can benefit local and indigenous communities today. This knowledge is part of traditional cultural and spiritual practices within these indigenous communities. The practices are directly tied to the unique relationship between Aboriginal Australians and their ecological landscapes. This relationship results in a socio-ecological system of balance between humans and nature Indigenous communities in Australia have specific generational traditional knowledge about weather patterns, environmental changes and climatic changes. These communities have adapted to climate change in the past and have knowledge that non-Indigenous people may be able to utilize to adapt to climate change currently and in the future.
Indigenous people have not been offered many opportunities or provided with sufficient platforms to influence and contribute their traditional knowledge to the creation of current international and local policies associated to climate change adaptation. Although, Indigenous people have pushed back on this reality, by creating their own platforms and trying to be active members in the conversation surrounding climate change including at international meetings. Specifically, Indigenous people of Australia have traditional knowledge to adapt to increased pressures of global environmental change.
Though some of this traditional knowledge was not utilised and conceivably lost with the introduction of white settlers in the 18th century, recently communities have begun to revitalize these traditional practices. Australian Aboriginal traditional knowledge includes language, cultural, spiritual practices, mythology and land management.
Responses to climate change
Indigenous knowledge has been passed down through the generations with the practice of oral tradition. Given the historical relationship between the land and the people and the larger ecosystem Aboriginal Australians choose to stay and adapt in similar ways to their ancestors before them. Aboriginal Australians have observed short and long term environmental changes and are highly aware of weather and climate changes. Recently, elders have begun to be utilised by indigenous and non-indigenous communities to understand traditional knowledge related to land management. This includes seasonal knowledge means indigenous knowledge pertaining to weather, seasonal cycles of plants and animals, and land and landscape management. The seasonal knowledge allows indigenous communities to combat environmental changes and may result in healthier social-ecological systems. Much of traditional landscape and land management includes keeping the diversity of flora and fauna as traditional foodways. Ecological calendars is one traditional framework used by Aboriginal Australian communities. These ecological calendars are way for indigenous communities to organize and communicate traditional ecological knowledge. The ecological calendars includes seasonal weather cycles related to biological, cultural, and spiritual ways of life.
Mitigation
Climate change mitigation focuses on steps taken to reduce greenhouse gas emissions. It is the set of preventative measures taken to curb global warming and climate change. Examples would be investing in clean fuel and using renewable energy such as wind and solar power.
According to the CSIRO and Garnaut Climate Change Review, climate change is expected to have numerous adverse effects on many species, regions, activities and much infrastructure and areas of the economy and public health in Australia. The Stern Report and Garnaut Review on balance expect these to outweigh the costs of mitigation.
The World Resources Institute identifies policy uncertainty and over-reliance on international markets as the top threats to Australia's GHG mitigation.
Emissions reductions
Internationally, Australia pledged as part of Paris Agreement to reduce emissions by 43% by 2030 and achieve net zero emissions by 2050. Domestically, the Clean Energy Act 2011 addresses GHG with an emissions cap, carbon price, and subsidies. Emissions by the electric sector are addressed by Renewable Energy targets at multiple scales, Australian Renewable Energy Agency (ARENA), Clean Energy Finance Corporation (CEFC), carbon capture and storage flagships, and feed-in tariffs on solar panels. Emissions by the industrial sector are addressed by the Energy Efficiency Opportunities (EEO) program.
Emissions by the building sector are addressed by building codes, minimum energy performance standards, Commercial Building Disclosure program, state energy-saving obligations, and the National Energy Saving Initiative. Emissions by the transportation sector are addressed by reduced fuel tax credits and vehicle emissions performance standards. Emissions by the agricultural sector are addressed by the Carbon Farming Initiative and state land-clearing laws. Emissions by the land use sector are addressed by the Clean Energy Future Package, which consists of the Carbon Farming Futures program, Diversity Fund, Regional Natural Resources Management Planning for Climate Change Fund, Indigenous Carbon Farming Fund, and Carbon Farming Skills program.
Forestry and forest-related options for carbon sinks
In Australia, forestry and forest-related options are the most significant and most easily achieved carbon sink making up 105 Mt per year CO2-e or about 75 per cent of the total figure attainable for the Australian state of Queensland from 2010 to 2050. Among the forestry options, forestry with the primary aim of carbon storage (called carbon forestry) has the highest attainable carbon storage capacity (77 Mt CO2-e/yr) while strategy balanced with biodiversity plantings can return 7–12 times more native vegetation for a 10%–30% reduction of carbon storage performance.
Legal strategies to encourage this form of biosequestration include permanent protection of forests in National Parks or on the World Heritage List, properly funded management and bans on use of rainforest timbers and inefficient uses such as woodchipping old growth forest.
Policies and legislation to achieve mitigation
Paris Agreement
The Paris agreement is a legally international agreement adopted at the COP 21, its main goal is to limit global warming to below 1.5 °C, compared to pre-industrial levels. The Nationally Determined Contributions (NDCs) are the plans to fight climate change adapted for each country. Every party in the agreement has different goals based on its own historical climate records and country's circumstances. All the goals for each country are stated in their NDC.
Australia's target regarding reductions from 2005 year levels:
26–28% reduction of greenhouse gases (GHG) until 2030 from 2005 levels. In 2022 the new Australian government officially declared the update of the targets to 43% reduction by 2030 and net zero emissions by 2050.
Gases covered in reductions: Carbon dioxide (), Methane (), Nitrous oxide (), Hydrofluorocarbon (HFCs), Perfluorinated compound (PFCs), Sulfur hexafluoride (SF6) and Nitrogen trifluoride (NF3).
Countries have different ways to achieve the established goals depending on resources. Australia's developed approach to support the NDC climate change plan is the following:
Enabling new technologies with low emissions and promoting economic growth.
Establish regional hydrogen exports to strengthen the country's industry and fund research in the field and enable distribution.
Improve charging and refueling infrastructure to enable companies and fleets to integrate new more sustainable vehicle technology.
The country has created a development fund whose purpose is for projects concerning carbon dioxide capture. The fund is for storage, use and carbon capture.
Investments in technological development that reduces emissions in the sectors of agriculture, industry, transport and manufacturing.
Climate solution package to increase investment in projects to generate clean energy. The package also includes extra funds to support development in the hard-to-reach sectors.
Australia has a legalised obligation for the major emitting sectors in the country where the emissions are to be kept below their baseline.
Australia has through funds such as Australia emission reduction fund contributed with 60 million tonnes reduction of greenhouse gases. The fund enables businesses to earn carbon credits. This is done by storing or preventing emissions through new sustainable techniques.
State legislation
Victoria
The Climate Change Act was adopted in 2017 and is part of a broader Victorian environmental legislation taking climate change into account. It establishes a net-zero emission target by 2050 and interim targets set every five years to adapt and keep Victoria on track with the 2050 goal.
Adaptation
According to the IPCC's 2001 Assessment Report, no matter how much effort is put into mitigating climate change, some amount of climate change cannot be avoided. The report shared that climate change adaptation should complement mitigation efforts. Adaptation is the approach that focuses on alleviating current problems brought about by global warming and climate change. It is the attempt to live with the changes in the environment and the economy that global warming has generated and will continue to generate. In short, it involves taking action to deal with the problems brought about by global warming and climate change. Examples include building better flood defences and avoiding the building of residential areas near low-lying, flood-prone areas. In cities with a proven vulnerability to climate change, investment is likely to require the strengthening of urban infrastructure, including storm drain systems, water supply and treatment plants, and protection or relocation of solid waste management and power generation facilities.
Coastal regions are likely to need large investment in physical infrastructure projects, specifically projects related to the effects of rising sea levels. Projects such as the construction of protective barriers against rising sea levels, the building of dams to retain and manage water, the redesign and development of port facilities and the improvement of the defence systems at coastal areas should be carried out.
Federal, state and territory policy makers have supported a National Biodiversity and Climate Change Action Plan that works to adapt to the impacts of climatic change and manage the effects on wildlife.
National government programs
Regional natural resource management (NRM) organisations
Federal natural resource goals, government agencies and non-government organizations established 56 regional natural resource management (NRM) organisations beginning in the mid-1990s. NRM organisations fall under the federal government Natural Heritage Trust. NRM operate according to individual constitutions, usually by the state government and others by community associations. Their boards are appointed by either the local government or community stakeholders. NRM Planning for Climate Fund, put $13.6 million toward helping NRMs plan land use in light of climate change by building a base of detailed climatic information.
National Climate Change Adaptation Programme
The Minister for Energy and Emissions Reduction has come up with the National Climate Change Adaptation Programme which aims to work with industries, scientific organisations, residents and other governments to create workable solutions. Some A$14 million over a period of four years (2008–2012) is to be spent on this initiative. The programme has forged strong research links in at-risk areas such as the Great Barrier Reef. Research conducted in the Great Barrier Reef is focused on developing methods to deal with climate change to protect the reef. It is hoped that this work will create a universal model for sustainable, cost-effective reef development. According to the programme's brochure: "National greenhouse mitigation policies and programmes are projected to reduce emissions by 94 million tonnes by 2010 – the equivalent of removing every motor vehicle in Australia from the road! However, the greenhouse gases already in the atmosphere and the growing emissions from around the world will affect our climate. Adaptation to climate change will complement action to reduce greenhouse gases".
Climate Adaptation Flagship
The Australian Commonwealth Scientific and Industrial Research Organisation (CSIRO) started the Climate Adaptation Flagship. Its aim is "enabling Australia to adapt more effectively to the impacts of climate change and variability and informing national planning, regulation and investment decisions". This is part of the National Research Flagships Program. It is designed to bring various stakeholders, i.e. research companies, industries, international connections, eminent scientists and CSIRO, together in hope of delivering practical solutions that address the pressing issues of Australia.
The Climate Adaptation Flagship project concerns both climate variability (or non-human causes, as defined by the United Nations Framework Convention on Climate Change) and climate change. The research budget for this Flagship for the year 2008–09 is close to A$30 million. There are four research prongs to this project: Pathways to adaptation; Sustainable cities and costs; Managing species and natural ecosystems; Adaptive primary industries, enterprises and communities.
National Climate Change Adaptation Research Facility
The National Climate Change Adaptation Research Facility (NCCARF) is hosted by Griffith University in Queensland and "leads the research community in a national interdisciplinary effort to generate the information needed by decision-makers in government and in vulnerable sectors and communities to manage the risks of climate change impacts".
The key roles of NCCARF include:
developing National Adaptation Research Plans to identify critical gaps in the information available to decision-makers
synthesising existing and emerging national and international research on climate change impacts and adaptation and developing targeted communication products
undertaking a program of Integrative Research to address national priorities, and
establishing and maintaining Adaptation Research Networks to link together key researchers and assist them in focusing on national research priorities.
The facility is a partnership between the Australian government's Department of Climate Change and Griffith University, with a consortium of funding partners and universities drawn from across the country.
The Local Adaptations Pathway Program
The Australian government is of the view that local government is critical in managing the impacts of climate change and seeks to assist local councils in studying and applying adaptation options. The programme is the Australian government's initiative to enable councils to go through climate change risk assessments and come up with action plans to prepare for the impacts the phenomenon may have on local society. Up to A$50,000 will be released. A list of councils successful in procuring the funding is provided on the programme's website.
Policies and legislation
In November 1981, the Office of National Assessments (intelligence agency) presented prime minister Malcolm Fraser with a classified-confidential assessment noting scientific acceptance of the greenhouse effect and resultant "measurably warmer" temperatures and "related climatic changes", and also projecting effects of possible doubling and quadrupling of atmospheric levels by the middle and end of the 21st century. The assessment focused on the implications for the country's fossil fuel industry.
In the late 1980s and early 1990s, there was clear Australian consensus about the need for action on climate change between the two major political parties. However, following the 1991 recession, incoming right wing governments began framing science of climate change as a continuing debate. In 1997, Australia joined the United States as the only countries to not ratify the Kyoto Protocol.
With voters influenced by events like the Millennium drought and 2006 film An Inconvenient Truth, both parties went to the 2007 election promising action on climate change, with the then opposition calling climate change the "greatest moral, economic and social challenge of our time". The incumbent Howard government lost, and the incoming Labor government immediately ratified the Kyoto Protocol. In 2009, before a bill could be passed, with the support of opposition leader Malcolm Turnbull, the opposition changed leaders to Tony Abbott, and supported by The Greens but for the opposite reason that Rudd's scheme was too weak and potentially locked in failure, blocked Rudd's Carbon Pollution Reduction Scheme.
In 2010, the Rudd government decided to delay the implementation of the Carbon Pollution Reduction Scheme (CPRS) until the end of the first commitment period of the Kyoto Protocol (ending in 2012). They cited the lack of bipartisan support for the CPRS and slow international progress on climate action as the reasons for the decision. In turn, the delay was strongly criticised by the Federal Opposition as well as community and grassroots action groups such as GetUp.
Following the unsuccessful Copenhagen Summit, the Rudd was replaced by Gillard as prime minister, who stated that "there will be no 'carbon tax' under the government I lead".
The Gillard Labor government established several government entities to manage Australia's response to climate change:
The Climate Change Authority, an independent statutory body that provides advice and performs research for the federal government on climate change.
The Clean Energy Regulator, an independent statutory body that administers federal government schemes to measure and reduce Australia's greenhouse gas emissions.
The Australian Renewable Energy Agency (ARENA), a corporate body that manages renewable energy programs.
The Clean Energy Finance Corporation (CEFC), a government-owned corporation that invests in clean energy technologies.
In 2011, Parliament passed the Clean Energy Act 2011, which introduced carbon pricing in Australia, colloquially known as a 'carbon tax'. It required large businesses, defined as those emitting over 25,000 tons of carbon dioxide equivalent annually, to purchase emissions permits. The strong backlash led by opposition leader Abbott led to her being replaced as leader by Rudd, then Abbott at the next election. Under his leadership, Australia became the first country to repeal a carbon pricing program.
In 2015, Abbott was replaced as prime minister by Minister for Communications Malcolm Turnbull under the condition that his climate policy would not change. Australia attended the 2015 United Nations Climate Change Conference and adopted the Paris Agreement. In limiting further action on climate change, Australia joined Russia, Turkey and Brazil in citing US President Trump's promise to withdraw from the Paris Agreement.
In 2018, Turnbull was replaced by Scott Morrison as leader of the Liberal Party and prime minister. Morrison won the 2019 election with an unchanged climate policy.
In June 2021, the Sustainable Development Report 2021 scored Australia last out of 193 United Nations member countries for action taken to reduce global greenhouse gas emissions, scoring 10 out of 100 in an assessment of fossil fuel emissions, emissions associated with imports and exports, and policies for pricing carbon.
In May 2022, the Coalition lost the federal election to the Labor Party, led by Anthony Albanese. In a machinery of government change, a new Department of Climate Change, Energy, the Environment and Water will be established. The new government committed to a 43% reduction in Australia's emissions by 2030 (compared to 2005 levels), and net zero emissions by 2050.
History of climate change policy in Australia
Domestic action to address climate change in Australia began in 1989, when Senator Graham Richardson proposed the first greenhouse gas emission reduction target of 20% by 2005. The Australian Government rejected this target. In 1990, Ros Kelly and Jon Kerin announced that the Australian Government would adhere to the goals initially proposed by Richardson but not to any economic detriment.
Australia signed the UNFCCC in 1992. This was followed by the release of the National Greenhouse Response Strategy (NGRS), which provided states and territories with the mechanisms to adhere to UNFCCC emission guidelines. Australia attended the first session of the Conference of the Parties to the UNFCCC in Berlin in March 1995. Throughout the 1990s, Australia regularly failed to meet its own emission targets and those set by the UNFCCC.
In 1997, Prime Minister John Howard announced that by 2010, an additional 2% of electricity would be sustainably sourced. The following year, the Australian Greenhouse Office (AGO) was established to monitor greenhouse gas reductions. The AGO later combined with the Department of Environment and Heritage. In April 1998, Australia became a party to the Kyoto Declaration. The Declaration was ratified in 2007 under Prime Minister Kevin Rudd.
In the Renewable Energy (Electricity) Act 2000, the Federal Government introduced the Mandatory Renewable Energy Target program, which aimed to sustainably source 10% of electrical energy by 2010. In 2011, the Mandatory Renewable Energy Target program was divided into the Large-Scale Renewable Energy Target and the Small-Scale Renewable Energy Scheme. In January 2003, the New South Wales State Government implemented the Greenhouse Gas Reduction Scheme (GGRS), which allowed carbon emissions to be traded.
Under Rudd, the Labor Government proposed the Carbon Pollution Reduction Scheme, which was intended to take effect in 2010. This scheme was rejected by the Greens for being too permissive and by Tony Abbott's Coalition for being economically detrimental. Under Prime Minister Julia Gillard, the Labor Party passed the Clean Energy Act 2011 to establish a carbon tax and put a price on greenhouse gas emissions. This carbon tax was a divisive partisan issue.
In 2012, the Coalition ran a campaign to repeal the carbon tax. Upon election victory in September 2013, Prime Minister Tony Abbott passed the Clean Energy Legislation (Carbon Tax Repeal) Bill. In replacement of the carbon tax, Abbott introduced the Direct Action Scheme to financially reward businesses for voluntarily reducing their carbon emissions. This was followed by a decision not to participate in the 19th session of the Conference of the Parties to the UNFCCC (COP-19).
Australia became a party to the Paris Agreement in 2015. In the agreement, Australia committed to reducing its emissions by 26% by 2030.
In 2019, Prime Minister Scott Morrison was criticised for a lack of commitment to addressing climate change while taking a vacation during the 2019 bushfires.
International cooperation
Internationally, Australia contributed to the creation of the Asia Pacific Rain Forest Partnership, International Coral Reef Initiative, International Partnership for Blue Carbon, Mission Innovation, Clean Energy Ministerial Forum, International Solar Alliance, and the Kigali Amendment to the Montreal Protocol. The government has also provided $1 billion to assist developing countries in reducing GHG emissions, partly through the United Nations Framework Convention on Climate Change Green Climate Fund. Australia's scientists also provide data on climate, emissions, impacts, and mitigation options for the Intergovernmental Panel on Climate Change assessments.
Under the Paris Agreement, Australia has committed to reducing emission by 26-28% below 2005 levels. This would mean reducing emissions by half per capita and by two-thirds across the economy. The Department of Environment and Energy noted in a 2017 review that no one policy could achieve what multiple, sector-specific ones have. This approach has manifested in Australia meeting its first Kyoto Protocol target. Australia is now bound to reducing emissions to at least 5% by 2020 under the Copenhagen Accord and Cancun Agreements and 0.5% less than 1990 levels by 2020 under their second target for the Kyoto Protocol.
While Australia opposed a 1.5 °C target at the 2015 negotiations for the Paris Agreement, in 2019, they supported the Kainaki II Declaration of the Pacific Islands Forum, which included this target. In 2022, Australia discussed hosting COP29 with its Pacific island neighbours in 2024 at the Pacific Islands Forum.
In November 2023 it was announced that Australia will offer 280 Tuvalu citizens displaced by climate change permanent residency in Australia per year, as part of a broad bilateral deal.
Society and culture
Politics
Despite the support of a clear scientific consensus, climate change has been a divisive or controversial issue in Australian politics since the 2000s. It has sometimes been referred to as a "culture war" in the country. Conservatives have generally opposed climate mitigation policies and renewable energy, instead favouring or supporting the country's coal and fossil fuels industries, which make up a large part of the economy. Proposed carbon pricing during the premiership of Julia Gillard proved highly divisive, and was later repealed under Tony Abbott. Climate change was a key issue in the 2022 federal election, where the Australian Labor Party and teal independents made gains in part due to promoting environmental policies.
Australian conservatives, with the support of strongly climate-skeptical media, have long opposed climate change mitigation and changes to energy policy. This is partly a strategy to foster the support of the country's coal and the fossil fuel industry, which are highly influential and a large employer in the country.
Activism
Climate change protests have taken place in Australia during the 21st century.In 2005, with support from Uniting Church and Catholic Earthcare, the Australian Conservation Foundation and the National Council of Churches Australia produced a brochure, Changing Climate, Changing Creation, which was distributed to churches across the country to call for action on climate change.
Rising Tide held environmental direct action protests in February 2007, where more than 100 small and medium-sized craft, including swimmers and people on surfboards, gathered in Newcastle harbour. Young people from the Real Action On Climate Change shut down two coal-fired power stations in September 2007. A 2009 "Walk Against Warming" drew 40,000 participants in Melbourne.
The Say Yes demonstrations took place on 5 June 2011, in which 45,000 people demonstrated in every major city nationwide in support of carbon pricing policies. Thousands of Australian children took part in school strikes for climate in 2018 and 2019. The September 2019 climate strikes attracted an estimated 180,000 to 300,000 participants across eight Australian capital cities and 140 urban centres, making it one of the largest protests in the country's history and one of the largest climate protests globally. Approximately 2,500 businesses also took part.
The response to the 2019–20 Australian bushfire season sparked protests in Sydney, Canberra, Melbourne, Victoria, Brisbane, Hobart, and outside the Australian High Commission in London. Prime Minister Scott Morrison was criticised for climate denial in the wake of the bushfires. Extinction Rebellion held rallies in London, Berlin, Madrid, Copenhagen and Stockholm calling for stronger climate action. Direct action group Blockade Australia began disruptive activism in 2021 and 2022. In 2023 another Rising Tide water blockade was held in Newcastle during which 3000 people took part and 109 were arrested. Despite the introduction of tougher penalties in New South Wales for such activity the majority of those facing court received dismissals with no conviction with magistrates acknowledging the protesters as “valuable contributors to society" and commending their “muscular good character.
Litigation
Groups including Rising Tide and Queensland Conservation have initiated legal challenges to coal mines under the Commonwealth EPBC legislation. In late 2006, Queensland Conservation lodged an objection to the greenhouse gas emissions from a large coal mine expansion proposed by Xstrata Coal Queensland Pty Ltd. QC's action aimed to have the true costs of the greenhouse gas emissions from coal mining recognised. The Newlands Coal Mine Expansion will produce 28.5 million tonnes of coal over its fifteen years of operation. The mining, transport and use of this coal will emit 84 million tonnes of into the atmosphere. Queensland Conservation aims to have reasonable and practical measures imposed on new mines to avoid, reduce or offset the emissions from the mining, transport and use of their coal. The Land and Resources Tribunal ruled against the case.
Media coverage
Projected impacts by location
The impacts of climate change will vary significantly across Australia. The Australian Government appointed Climate Commission have prepared summary reports on the likely impacts of climate change for regions across Australia, including: Queensland, NSW, Victoria and Tasmania.
Capital cities
Adelaide
Adelaide will get hotter and drier with rainfall predicted to decline 8% to 29% by 2090 and average temperature to increase between 4 and 0.9 degrees. The number of days above 35 degrees will increase by 50% in 2090 and the number of days above 40 degrees will double. Bringing it close to Northampton, Western Australia, for temperature and Kadina, South Australia, for rainfall.
Sea levels will rise with predictions between 39 and 61 cm by 2090. And extreme seas are predicted to rise as well, with the CSIRO predicting buildings in Port Adelaide would need to be raised by 50 to 81 cm to keep the amount of flooding incidents the same as recorded between 1986 and 2005.
Brisbane
In a RCP 4.5 scenario Brisbane's temperature will be similar to that of Rockhampton today while rainfall will be closest to Gympie. The CSIRO predicts rainfall in Brisbane will fall between -23% (235 mm) and -4% (45.3 mm) annually by 2090 while temperature will rise between 4.2° and 0.9°. The number of hot days and hot nights will double by 2050, with many people needing to avoid outdoor activity in summer. Further urban growth increases the number of hot nights even further. Hot nights increase deaths amongst the elderly. Rainfall will be deposited in less frequent more intense rain events, fire days will also get more frequent while frost days will decrease. Sea levels are predicted to rise by 80 cm by 2100 and there will be more frequent sea level extremes.
Darwin
In a RCP 4.5 scenario Darwin's temperature will be similar to that of Daly River now, with its rainfall most like that of Milikapiti. In a RCP 8.5 scenario, indicating higher greenhouse gas emissions, Darwin's temperature loses any close comparison in Australia being significantly hotter than every town in Australia is today (with the exclusion of Halls Creek in Autumn).
Sydney
Suburbs of Sydney like Manly, Botany, Narrabeen, Port Botany, and Rockdale, which lie on rivers like the Parramatta, face risks of flooding in low-lying areas such as parks (like Timbrell Park and Majors Bay Reserve), or massive expenses in rebuilding seawalls to higher levels. Sea levels are predicted to rise between 38 and 66 cm by 2090.
Temperature in Sydney will increase between 0.9° and 4.2°, while rainfall will decrease between -23% and -4% by 2090. Bringing Sydney's climate close to that of Beaudesert today (under a RCP 8.5 scenario). Different parts of Sydney will warm differently with the greatest impact expected in Western Sydney and Hawkesbury, these areas can expect 5 to 10 additional hot days by 2030. Similarly future rainfall patterns will be different to those today, with more rain expected to fall in summer and autumn and less expected in Winter and Spring. Fire danger days will increase in number by 2070.
Melbourne
Sea levels are projected to rise between 0.37 cm and 0.59 cm at Williamstown (the closest covered point) by 2090. At the higher end of this scale areas in and around Melbourne would be impacted. With some of the most vulnerable areas being the Docklands development and several marinas and berths in Port Phillip. Melbourne's climate will become similar in terms of total rainfall and average temperature to that of Dubbo today, with temperatures warming between 0.9° and 3.8° and total annual rainfall falling between -10% and -4% by 2090. Rainfall patterns will also change with 20% less rainfall predicted during spring in 2050, which may impact the severity of summer bushfires.
The increases in temperature and decrease in rainfall will have a series of follow on effects on the city, including a possible 35% reduction in trees in Melbourne by 2040. And more frequent ambulance callouts and more deaths due to heatwaves. Climate change will cost Melbourne City $12.6bn by 2050 and be closer to Wangaratta's climate.
Perth
In 2090 Perth is predicted to have the rainfall of Yanchep today and the temperature of Geraldton using the RCP 4.5 scenario. Rainfall is predicted to fall between -29% (-226 mm) and -8% (-66 mm) and temperature predicted to rise between 0.9° and 4°. Perth may see the number of days above 35° increase from 28 per year on average to 36 in 2030, and to between 40 and 63 in 2090. While frost days will decrease. Rainfall will increase in intensity while decreasing on average. Drought days in the south west as a whole may increase by as much as 80% versus 20% for Australia. The danger from fire will increase with more fire days for all of Western Australia.
Hobart
By 2090 Hobart's climate will warm between 3.8° and 0.9°, rainfall will decline between 4% and 10%. The temperature pattern will be similar to Port Lincoln while rainfall will be closer to Condoblin's today in a RCP 8.5 scenario. Warm spells are likely to last longer and rainfall will trend to more intense rain events dumping less rain annually, increasing the risk of erosion and flooding. Flooding on the Derwent river will become more regular and extreme with a current 1-in-100-year event being possibly a 2-to-6-year event in 2090. Hobart's fire season will get longer.
States
Victoria
By 2050, Victoria's annual temperature will increase up to 2.4 °C, with twice the number of very hot days compared to 1986-2005, longer fire seasons, less rainfall and snowfall in cool season and a rise in sea levels about 24 cm.
Historical aspects
Pre-instrumental climate change
Paleoclimatic records indicate that during glacial maxima Australia was extremely arid, with plant pollen fossils showing deserts as far as northern Tasmania and a vast area of less than 12% vegetation cover over all of South Australia and adjacent regions of other states. Forest cover was largely limited to sheltered areas of the east coast and the extreme southwest of Western Australia.
During these glacial maxima the climate was also much colder and windier than today. Minimum temperatures in winter in the centre of the continent were as much as lower than they are today. Hydrological evidence for dryness during glacial maxima can also be seen at major lakes in Victoria's Western District, which dried up between around 20,000 and 15,000 years ago and re-filled from around 12,000 years ago.
During the early Holocene, there is evidence from Lake Frome in South Australia and Lake Woods near Tennant Creek that the climate between 8,000 and 9,500 years ago and again from 7,000 to 4,200 years ago was considerably wetter than over the period of instrumental recording since about 1885. The research that gave these records also suggested that the rainfall flooding Frome was certainly summer-dominant rainfall because of pollen counts from grass species. Other sources suggest that the Southern Oscillation may have been weaker during the early Holocene and rainfall over northern Australia less variable as well as higher. The onset of modern conditions with periodic wet season failure is dated at around 4,000 years before the present.
In southern Victoria, there is evidence for generally wet conditions except for a much drier spell between about 3,000 and 2,100 years before the present, when it is believed Lake Corangamite fell to levels well below those observed between European settlement and the 1990s. After this dry period, Western District lakes returned to their previous levels fairly quickly and by 1800 they were at their highest levels in the forty thousand years of record available.
Elsewhere, data for most of the Holocene are deficient, largely because methods used elsewhere to determine past climates (like tree-ring data) cannot be used in Australia owing to the character of its soils and climate. Recently, however, coral cores have been used to examine rainfall over those areas of Queensland draining into the Great Barrier Reef. The results do not provide conclusive evidence of man-made climate change, but do suggest the following:
There has been a marked increase in the frequency of very wet years in Queensland since the end of the Little Ice Age, a theory supported by there being no evidence for any large Lake Eyre filling during the LIA.
The dry era of the 1920s and 1930s may well have been the driest period in Australia over the past four centuries.
A similar study, not yet published, is planned for coral reefs in Western Australia.
Records exist of floods in a number of rivers, such as the Hawkesbury, from the time of first settlement. These suggest that, for the period beginning with the first European settlement, the first thirty-five years or so were wet and were followed by a much drier period up to the mid-1860s, when usable instrumental records started.
Development of an instrumental network for climate records
Although rain gauges were installed privately by some of the earliest settlers, the first instrumental climate records in Australia were not compiled until 1840 at Port Macquarie. Rain gauges were gradually installed at other major centres across the continent, with the present gauges in Melbourne and Sydney dating from 1858 and 1859, respectively.
In eastern Australia, where the continent's first large-scale agriculture began, a large number of rain gauges were installed during the 1860s and by 1875 a comprehensive network had been developed in the "settled" areas of that state. With the spread of the pastoral industry to the north of the continent during this period, rain gauges were established extensively in newly settled areas, reaching Darwin by 1869, Alice Springs by 1874, and the Kimberley, Channel Country and Gulf Savannah by 1880.
By 1885, most of Australia had a network of rainfall reporting stations adequate to give a good picture of climatic variability over the continent. The exceptions were remote areas of western Tasmania, the extreme southwest of Western Australia, Cape York Peninsula, the northern Kimberley and the deserts of northwestern South Australia and southeastern Western Australia. In these areas good-quality climatic data were not available for quite some time after that.
Temperature measurements, although made at major population centres from days of the earliest rain gauges, were generally not established when rain gauges spread to more remote locations during the 1870s and 1880s. Although they gradually caught up in number with rain gauges, many places which have had rainfall data for over 125 years have only a few decades of temperature records.
|
Physical sciences
|
Climate change
|
Earth science
|
11664252
|
https://en.wikipedia.org/wiki/Dromiidae
|
Dromiidae
|
Dromiidae is a family of crabs, often referred to as sponge crabs. They are small or medium-sized crabs which get their name from the ability to shape a living sponge into a portable shelter for themselves. A sponge crab cuts out a fragment from a sponge and trims it to its own shape using its claws. The last two pairs of legs are shorter than other legs and bend upward over the crab's carapace, to hold the sponge in place. The sponge grows along with the crab, providing a consistent shelter.
Subfamilies and genera
The family Dromiidae contains the following subfamilies and genera:
Dromiinae
Alainodromia
Ameridromia
Ascidiophilus
Austrodromidia
Barnardomia
Conchoecetes
Costadromia
Cryptodromia
Cryptodromiopsis
Desmodromia
Dromia
Dromidia
Dromidiopsis
Dromilites
Epigodromia
Epipedodromia
Eudromidia
Exodromidia
Foredromia
Fultodromia
Haledromia
Hemisphaerodromia
Homalodromia
Kerepesia
Kromtitis
Lamarckdromia
Lauridromia
Lewindromia
Lucanthonisia
Mclaydromia
Metadromia
Moreiradromia
Noetlingia
Paradromia
Petalomera
Platydromia
Pseudodromia
Speodromia
Stebbingdromia
Sternodromia
Stimdromia
Takedromia
Tumidodromia
Tunedromia
Hypoconchinae
Hypoconcha
Sphaerodromiinae
Eodromia
Frodromia
Sphaerodromia
|
Biology and health sciences
|
Crabs and hermit crabs
|
Animals
|
11669530
|
https://en.wikipedia.org/wiki/Nose
|
Nose
|
A nose is a sensory organ and respiratory structure in vertebrates. It consists of a nasal cavity inside the head, and an external nose on the face. The external nose houses the nostrils, or nares, a pair of tubes providing airflow through the nose for respiration. Where the nostrils pass through the nasal cavity they widen, are known as nasal fossae, and contain turbinates and olfactory mucosa. The nasal cavity also connects to the paranasal sinuses (dead-end air cavities for pressure buffering and humidification). From the nasal cavity, the nostrils continue into the pharynx, a switch track valve connecting the respiratory and digestive systems.
In humans, the nose is located centrally on the face and serves as an alternative respiratory passage especially during suckling for infants.
The protruding nose that is completely separate from the mouth part is a characteristic found only in therian mammals. It has been theorized that this unique mammalian nose evolved from the anterior part of the upper jaw of the reptilian-like ancestors (synapsids).
Air treatment
Acting as the first interface between the external environment and an animal's delicate internal lungs, a nose conditions incoming air, both as a function of thermal regulation and filtration during respiration, as well as enabling the sensory perception of smell.
Hair inside nostrils filter incoming air, as a first line of defense against dust particles, smoke, and other potential obstructions that would otherwise inhibit respiration, and as a kind of filter against airborne illness. In addition to acting as a filter, mucus produced within the nose supplements the body's effort to maintain temperature, as well as contributes moisture to integral components of the respiratory system. Capillary structures of the nose warm and humidify air entering the body; later, this role in retaining moisture enables conditions for alveoli to properly exchange O2 for CO2 (i.e., respiration) within the lungs. During exhalation, the capillaries then aid recovery of some moisture, mostly as a function of thermal regulation, again.
Sense of direction
The wet nose of dogs is useful for the perception of direction. The sensitive cold receptors in the skin detect the place where the nose is cooled the most and this is the direction a particular smell that the animal just picked up comes from.
Structure in air-breathing forms
In amphibians and lungfish, the nostrils open into small sacs that, in turn, open into the forward roof of the mouth through the choanae. These sacs contain a small amount of olfactory epithelium, which, in the case of caecilians, also lines a number of neighbouring tentacles. Despite the general similarity in structure to those of amphibians, the nostrils of lungfish are not used in respiration, since these animals breathe through their mouths. Amphibians also have a vomeronasal organ, lined by olfactory epithelium, but, unlike those of amniotes, this is generally a simple sac that, except in salamanders, has little connection with the rest of the nasal system.
In reptiles, the nasal chamber is generally larger, with the choanae located much further back in the roof of the mouth. In crocodilians, the chamber is exceptionally long, helping the animal to breathe while partially submerged. The reptilian nasal chamber is divided into three parts: an anterior vestibule, the main olfactory chamber, and a posterior nasopharynx. The olfactory chamber is lined by olfactory epithelium on its upper surface and possesses a number of turbinates to increase the sensory area. The vomeronasal organ is well-developed in lizards and snakes, in which it no longer connects with the nasal cavity, opening directly into the roof of the mouth. It is smaller in turtles, in which it retains its original nasal connection, and is absent in adult crocodilians.
Birds have a similar nose to reptiles, with the nostrils located at the upper rear part of the beak. Since they generally have a poor sense of smell, the olfactory chamber is small, although it does contain three turbinates, which sometimes have a complex structure similar to that of mammals. In many birds, including doves and fowls, the nostrils are covered by a horny protective shield. The vomeronasal organ of birds is either under-developed or altogether absent, depending on the species.
The nasal cavities in mammals are both fused into one. Among most species, they are exceptionally large, typically occupying up to half the length of the skull. In some groups, however, including primates, bats, and cetaceans, the nose has been secondarily reduced, and these animals consequently have a relatively poor sense of smell. The nasal cavity of mammals has been enlarged, in part, by the development of a palate cutting off the entire upper surface of the original oral cavity, which consequently becomes part of the nose, leaving the palate as the new roof of the mouth. The enlarged nasal cavity contains complex turbinates forming coiled scroll-like shapes that help to warm the air before it reaches the lungs. The cavity also extends into neighbouring skull bones, forming additional air cavities known as paranasal sinuses.
In cetaceans, the nose has been reduced to one or two blowholes, which are the nostrils that have migrated to the top of the head. This adaptation gave cetaceans a more streamlined body shape and the ability to breathe while mostly submerged. Conversely, the elephant's nose has elaborated into a long, muscular, manipulative organ called the trunk.
The vomeronasal organ of mammals is generally similar to that of reptiles. In most species, it is located in the floor of the nasal cavity, and opens into the mouth via two nasopalatine ducts running through the palate, but it opens directly into the nose in many rodents. It is, however, lost in bats, and in many primates, including humans.
In fish
Fish have a relatively good sense of smell. Unlike that of tetrapods, the nose has no connection with the mouth, nor any role in respiration. Instead, it generally consists of a pair of small pouches located behind the nostrils at the front or sides of the head. In many cases, each of the nostrils is divided into two by a fold of skin, allowing water to flow into the nose through one side and out through the other.
The pouches are lined by olfactory epithelium, and commonly include a series of internal folds to increase the surface area, often forming an elaborate "olfactory rosette". In some teleosts, the pouches branch off into additional sinus-like cavities, while in coelacanths, they form a series of tubes.
In the earliest vertebrates, there was only one nostril and olfactory pouch, and the nasal passage was connected to the hypophysis. The same anatomy is observed in the most primitive living vertebrates, the lampreys and hagfish. In gnathostome ancestors, the olfactory apparatus gradually became paired (presumably to allow sense of direction of smells), and freeing the midline from the nasal passage allowed evolution of jaws.
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Biology and health sciences
|
Nervous system
| null |
4046824
|
https://en.wikipedia.org/wiki/Gauss%E2%80%93Seidel%20method
|
Gauss–Seidel method
|
In numerical linear algebra, the Gauss–Seidel method, also known as the Liebmann method or the method of successive displacement, is an iterative method used to solve a system of linear equations. It is named after the German mathematicians Carl Friedrich Gauss and Philipp Ludwig von Seidel. Though it can be applied to any matrix with non-zero elements on the diagonals, convergence is only guaranteed if the matrix is either strictly diagonally dominant, or symmetric and positive definite. It was only mentioned in a private letter from Gauss to his student Gerling in 1823. A publication was not delivered before 1874 by Seidel.
Description
Let be a square system of linear equations, where:
When and are known, and is unknown, the Gauss–Seidel method can be used to iteratively approximate . The vector denotes the initial guess for , often for . Denote by the -th approximation or iteration of , and by the approximation of at the next (or -th) iteration.
Matrix-based formula
The solution is obtained iteratively via
where the matrix is decomposed into a lower triangular component , and a strictly upper triangular component such that . More specifically, the decomposition of into and is given by:
Why the matrix-based formula works
The system of linear equations may be rewritten as:
The Gauss–Seidel method now solves the left hand side of this expression for , using the previous value for on the right hand side. Analytically, this may be written as
Element-based formula
However, by taking advantage of the triangular form of , the elements of can be computed sequentially for each row using forward substitution:
Notice that the formula uses two summations per iteration which can be expressed as one summation that uses the most recently calculated iteration of . The procedure is generally continued until the changes made by an iteration are below some tolerance, such as a sufficiently small residual.
Discussion
The element-wise formula for the Gauss–Seidel method is related to that of the (iterative) Jacobi method, with an important difference:
In Gauss-Seidel, the computation of uses the elements of that have already been computed, and only the elements of that have not been computed in the -th iteration. This means that, unlike the Jacobi method, only one storage vector is required as elements can be overwritten as they are computed, which can be advantageous for very large problems.
However, unlike the Jacobi method, the computations for each element are generally much harder to implement in parallel, since they can have a very long critical path, and are thus most feasible for sparse matrices. Furthermore, the values at each iteration are dependent on the order of the original equations.
Gauss-Seidel is the same as successive over-relaxation with .
Convergence
The convergence properties of the Gauss–Seidel method are dependent on the matrix . Namely, the procedure is known to converge if either:
is symmetric positive-definite, or
is strictly or irreducibly diagonally dominant.
The Gauss–Seidel method may converge even if these conditions are not satisfied.
Golub and Van Loan give a theorem for an algorithm that splits into two parts. Suppose is nonsingular. Let be the spectral radius of . Then the iterates defined by converge to for any starting vector if is nonsingular and .
Algorithm
Since elements can be overwritten as they are computed in this algorithm, only one storage vector is needed, and vector indexing is omitted. The algorithm goes as follows:
algorithm Gauss–Seidel method is
inputs: ,
repeat until convergence
for from 1 until do
for from 1 until do
if ≠ then
end if
end (-loop)
end (-loop)
check if convergence is reached
end (repeat)
Examples
An example for the matrix version
A linear system shown as is given by:
Use the equation
in the form
where:
Decompose into the sum of a lower triangular component and a strict upper triangular component :
The inverse of is:
Now find:
With and the vectors can be obtained iteratively.
First of all, choose , for example The closer the guess to the final solution, the fewer iterations the algorithm will need.
Then calculate:
As expected, the algorithm converges to the solution:
.
In fact, the matrix is strictly diagonally dominant, but not positive definite.
Another example for the matrix version
Another linear system shown as is given by:
Use the equation
in the form
where:
Decompose into the sum of a lower triangular component and a strict upper triangular component :
The inverse of is:
Now find:
With and the vectors can be obtained iteratively.
First of all, we have to choose , for example
Then calculate:
In a test for convergence we find that the algorithm diverges. In fact, the matrix is neither diagonally dominant nor positive definite.
Then, convergence to the exact solution
is not guaranteed and, in this case, will not occur.
An example for the equation version
Suppose given equations and a starting point .
At any step in a Gauss-Seidel iteration, solve the first equation for in terms of ; then solve the second equation for in terms of just found and the remaining ; and continue to . Then, repeat iterations until convergence is achieved, or break if the divergence in the solutions start to diverge beyond a predefined level.
Consider an example:
Solving for and gives:
Suppose is the initial approximation, then the first approximate solution is given by:
Using the approximations obtained, the iterative procedure is repeated until the desired accuracy has been reached. The following are the approximated solutions after four iterations.
The exact solution of the system is .
An example using Python and NumPy
The following iterative procedure produces the solution vector of a linear system of equations:
import numpy as np
ITERATION_LIMIT = 1000
# initialize the matrix
A = np.array(
[
[10.0, -1.0, 2.0, 0.0],
[-1.0, 11.0, -1.0, 3.0],
[2.0, -1.0, 10.0, -1.0],
[0.0, 3.0, -1.0, 8.0],
]
)
# initialize the RHS vector
b = np.array([6.0, 25.0, -11.0, 15.0])
print("System of equations:")
for i in range(A.shape[0]):
row = [f"{A[i,j]:3g}*x{j+1}" for j in range(A.shape[1])]
print("[{0}] = [{1:3g}]".format(" + ".join(row), b[i]))
x = np.zeros_like(b, np.float_)
for it_count in range(1, ITERATION_LIMIT):
x_new = np.zeros_like(x, dtype=np.float_)
print(f"Iteration {it_count}: {x}")
for i in range(A.shape[0]):
s1 = np.dot(A[i, :i], x_new[:i])
s2 = np.dot(A[i, i + 1 :], x[i + 1 :])
x_new[i] = (b[i] - s1 - s2) / A[i, i]
if np.allclose(x, x_new, rtol=1e-8):
break
x = x_new
print(f"Solution: {x}")
error = np.dot(A, x) - b
print(f"Error: {error}")
Produces the output:
System of equations:
[ 10*x1 + -1*x2 + 2*x3 + 0*x4] = [ 6]
[ -1*x1 + 11*x2 + -1*x3 + 3*x4] = [ 25]
[ 2*x1 + -1*x2 + 10*x3 + -1*x4] = [-11]
[ 0*x1 + 3*x2 + -1*x3 + 8*x4] = [ 15]
Iteration 1: [ 0. 0. 0. 0.]
Iteration 2: [ 0.6 2.32727273 -0.98727273 0.87886364]
Iteration 3: [ 1.03018182 2.03693802 -1.0144562 0.98434122]
Iteration 4: [ 1.00658504 2.00355502 -1.00252738 0.99835095]
Iteration 5: [ 1.00086098 2.00029825 -1.00030728 0.99984975]
Iteration 6: [ 1.00009128 2.00002134 -1.00003115 0.9999881 ]
Iteration 7: [ 1.00000836 2.00000117 -1.00000275 0.99999922]
Iteration 8: [ 1.00000067 2.00000002 -1.00000021 0.99999996]
Iteration 9: [ 1.00000004 1.99999999 -1.00000001 1. ]
Iteration 10: [ 1. 2. -1. 1.]
Solution: [ 1. 2. -1. 1.]
Error: [ 2.06480930e-08 -1.25551054e-08 3.61417563e-11 0.00000000e+00]
Program to solve arbitrary number of equations using Matlab
The following code uses the formula
function x = gauss_seidel(A, b, x, iters)
for i = 1:iters
for j = 1:size(A,1)
x(j) = (b(j) - sum(A(j,:)'.*x) + A(j,j)*x(j)) / A(j,j);
end
end
end
|
Mathematics
|
Linear algebra
| null |
4047104
|
https://en.wikipedia.org/wiki/Jacobi%20method
|
Jacobi method
|
In numerical linear algebra, the Jacobi method (a.k.a. the Jacobi iteration method) is an iterative algorithm for determining the solutions of a strictly diagonally dominant system of linear equations. Each diagonal element is solved for, and an approximate value is plugged in. The process is then iterated until it converges. This algorithm is a stripped-down version of the Jacobi transformation method of matrix diagonalization. The method is named after Carl Gustav Jacob Jacobi.
Description
Let be a square system of n linear equations, where:
When and are known, and is unknown, we can use the Jacobi method to approximate . The vector denotes our initial guess for (often for ). We denote as the k-th approximation or iteration of , and is the next (or k+1) iteration of .
Matrix-based formula
Then A can be decomposed into a diagonal component D, a lower triangular part L and an upper triangular part U:The solution is then obtained iteratively via
Element-based formula
The element-based formula for each row is thus:The computation of requires each element in except itself. Unlike the Gauss–Seidel method, we cannot overwrite with , as that value will be needed by the rest of the computation. The minimum amount of storage is two vectors of size n.
Algorithm
Input: , (diagonal dominant) matrix A, right-hand side vector b, convergence criterion
Output:
Comments: pseudocode based on the element-based formula above
while convergence not reached do
for i := 1 step until n do
for j := 1 step until n do
if j ≠ i then
end
end
end
increment k
end
Convergence
The standard convergence condition (for any iterative method) is when the spectral radius of the iteration matrix is less than 1:
A sufficient (but not necessary) condition for the method to converge is that the matrix A is strictly or irreducibly diagonally dominant. Strict row diagonal dominance means that for each row, the absolute value of the diagonal term is greater than the sum of absolute values of other terms:
The Jacobi method sometimes converges even if these conditions are not satisfied.
Note that the Jacobi method does not converge for every symmetric positive-definite matrix. For example,
Examples
Example question
A linear system of the form with initial estimate is given by
We use the equation , described above, to estimate . First, we rewrite the equation in a more convenient form , where and . From the known values
we determine as
Further, is found as
With and calculated, we estimate as :
The next iteration yields
This process is repeated until convergence (i.e., until is small). The solution after 25 iterations is
Example question 2
Suppose we are given the following linear system:
If we choose as the initial approximation, then the first approximate solution is given by
Using the approximations obtained, the iterative procedure is repeated until the desired accuracy has been reached. The following are the approximated solutions after five iterations.
The exact solution of the system is .
Python example
import numpy as np
ITERATION_LIMIT = 1000
# initialize the matrix
A = np.array([[10., -1., 2., 0.],
[-1., 11., -1., 3.],
[2., -1., 10., -1.],
[0.0, 3., -1., 8.]])
# initialize the RHS vector
b = np.array([6., 25., -11., 15.])
# prints the system
print("System:")
for i in range(A.shape[0]):
row = [f"{A[i, j]}*x{j + 1}" for j in range(A.shape[1])]
print(f'{" + ".join(row)} = {b[i]}')
print()
x = np.zeros_like(b)
for it_count in range(ITERATION_LIMIT):
if it_count != 0:
print(f"Iteration {it_count}: {x}")
x_new = np.zeros_like(x)
for i in range(A.shape[0]):
s1 = np.dot(A[i, :i], x[:i])
s2 = np.dot(A[i, i + 1:], x[i + 1:])
x_new[i] = (b[i] - s1 - s2) / A[i, i]
if x_new[i] == x_new[i-1]:
break
if np.allclose(x, x_new, atol=1e-10, rtol=0.):
break
x = x_new
print("Solution: ")
print(x)
error = np.dot(A, x) - b
print("Error:")
print(error)
Weighted Jacobi method
The weighted Jacobi iteration uses a parameter to compute the iteration as
with being the usual choice.
From the relation , this may also be expressed as
.
Convergence in the symmetric positive definite case
In case that the system matrix is of symmetric positive-definite type one can show convergence.
Let be the iteration matrix.
Then, convergence is guaranteed for
where is the maximal eigenvalue.
The spectral radius can be minimized for a particular choice of as follows
where is the matrix condition number.
|
Mathematics
|
Linear algebra
| null |
4047117
|
https://en.wikipedia.org/wiki/Motorcycle%20taxi
|
Motorcycle taxi
|
A motorcycle taxi, or cart bike or bike taxi, is a licensed form of transport in some countries. The taxi typically carries one passenger, who "rides pillion" behind the motorcycle operator. Multiple passengers are common in some countries.
Brazil
According to some sources, motorcycle taxi service in Brazil began in 1994, in Crateús, in the state of Ceará, when an employee of the Bank of Brazil Other sources state that it started in Bauru, São Paulo, in 1996, when an unemployed biker hung a banner across the road to the city, reading "help a biker racing to 1.00 real." Today, almost all Brazilian cities have motorcycle taxi services. Recently, they have appeared in poorer and less urban areas, where young people increasingly support themselves by driving them.
Typically, the fare is a flat fee, regardless of the distance traveled. However, the charge may vary according to the time of day or day of the week, or increase for distances that are greater than usual.
Licensing requirements for motorcycle taxis vary by municipality. Small towns tend not to regulate them at all, while in larger cities, they are regulated in much the same way as taxicabs. In July 2009, the Brazilian Senate approved standards for motorcycle taxi drivers and motorcycle couriers. They must be at least 21 years old, have held a Category A drivers licence for at least two years, and have attended a training course.
Cambodia
In Phnom Penh and other cities in Cambodia, motorcycle taxis are widely available as a form of low-cost public transport. Motorcycle taxi drivers, who are almost exclusively male, are called motodops (). They tend to hang around outside major tourist attractions, office buildings, public markets, and near the corners of residential streets. There is no regulated system of training or bike maintenance and no common uniform, so anyone on his way home from the market might offer you a ride (and the driver's intentions can generally be trusted, the state of his bike, a little less so). Always negotiate the fare in advance (use gestures, if necessary). Don't expect a motodop to understand English or to read a map - he'll likely flag somebody down who can help translate or navigate, if necessary. Fares vary depending on distance and weather but should always be cheaper than a tuk-tuk. Fares are higher at night and when embarking from tourist areas. You'll get a better rate if you can negotiate in passable Khmer, but have a heart: these are generally the folks that live on a few dollars or less per day. As of 2014, helmet laws apply only to drivers, so bring your own helmet if you're worried about safety, but it's not legally required.
The omnipresent ‘moto’ is the most common and fastest form of public transportation. Motos can be found virtually everywhere in town, just step to the curb and they will find you. Motos cost from 1500R-4000R for a trip in town and $6-$8 per day. Prices go up at night and for multiple passengers.
Cameroon
Motorcycle taxis are also the most common form of transportation in Maroua, Cameroon. Multiple passengers are carried on most trips; as many as four children are sometimes carried on a single motorcycle. Helmets are rarely used, but the traffic and speed are moderate in the city. Short distances cost about 200 francs, less than US$1.
China
In mainland China, motorcycle taxi service can be traced back to the late 1980s and early 1990s. There are currently motorcycle taxis throughout China, including in Beijing, Shanghai, and Guangzhou. They are popular primarily due to their low cost: the fare for short trips is just 5 yuan (less than US$1) per person.
India
In Goa, India, motorcycle taxis are required to be licensed. Driven by men called pilots, they are much cheaper than other taxis, although a passenger can only carry a backpack as luggage. In some parts of the state, motorcycle drivers are legally required to wear helmets, but any passengers riding pillion are not. Motorcycle taxis can usually be identified by their distinctive yellow and black colours. There is a practice to fix the fare in advance, and trips are not metered.
In last few years, a few companies such as Rapido, Uber and Ola have come up in multiple cities in India providing bike taxi services. With the Central Government's rule of allowing two-wheelers as legal and commercial vehicles and 8 states already legalized the same, it has become easier for the companies to design a working framework to provide easy and comfortable commute to the people.
Indonesia
Motorcycle taxis are a very common form of unlicensed transport in Indonesia, where they are known as ojek. Ojek can be found in most areas of the country, from towns where traffic jams commonly hinder other forms of transport, to rural areas inaccessible by four-wheeled vehicles. Because of the traffic, ojek are often the fastest form of transport, especially in big urban areas such as Jakarta, Surabaya, or Medan. Many people choose them over taxicabs, which are safer, but slower and more expensive.
Many ojek drivers either own their vehicles or are buying them on credit, although in some areas, stolen motorcycles are common. The widespread availability of cheap, domestic motorcycles made by Honda, Yamaha, and Suzuki, and even cheaper ones imported from China, as well as credit schemes with which to purchase these, have resulted in the rapid growth of ojek. The ease with which driver's licences can be obtained has also been a contributing factor.
Before the trip begins, the passenger usually haggles with the driver over the fare, which generally ranges from 5,000 to 10,000 rupiah (about US$0.50 to US$1.00) for short trips, longer trips will be more expensive. The fare may be different from one city to another city, as big city ojek will have higher fares than the smaller city ojek. Indonesia traffic law requires motorcycle riders and passengers to wear helmets; often on ojek, however, only the driver does so. Although the driver will sometimes provide a helmet for the passenger, more often, drivers simply avoid main streets, and the attention of police.
The name of Gojek is derived from the word ojek.
Mexico
In Mexico, there are thousands of motorcycle taxis. Their arrangements are informal (not traditional companies). They have precarious working conditions, long hours (11.3 hours a day), low wages (US$59.18 per week), and no social protections or benefits. 6.3% reported suffering from a disease, 49.5% corresponded to musculoskeletal conditions and only 11.6% were affiliated to any health system. 53.8% are owners of the vehicle and, although it does not seem to influence physical illness (P=0.03), it is related to the psychosocial ones (P=0.260).
Nigeria
Nigeria has about three million motorcycle taxis, locally called okadas, with over one million in Lagos alone. In Lagos, new rules prohibit okadas from carrying pregnant women or children. Authorities say okadas will be stopped from driving the wrong way, and the number of roads on which they are authorized to travel will be sharply reduced.
Philippines
Motorcycle taxis in the Philippines usually have sidecars, or seats extended sideways, often by use of a T-shaped crossbeam. The latter type of taxi is known as habal-habal or a skylab, owing to its crude resemblance to the Skylab space station which orbited the Earth in the 1970s.
Covered, three-wheel auto rickshaws, known as tricycles, are also a common mode of transport.
Angkas is a Philippine motorcycle vehicle for hire and delivery service company based in Makati, Metro Manila. Its competition in passenger market is JoyRide.
Motorcycle taxis were deemed illegal in 2020 due to possible exposure of passengers and riders to COVID-19 when in contact with each other, especially in the cities.
Thailand
Motorcycle taxis (, ; , ; or , ) are a common form of public transport in Bangkok and most other cities, towns, and villages in Thailand. They are generally used for short trips. In Bangkok, there are motorcycle taxi queues on many sois, or side streets, and the queues are regulated by land transport authority. Licensed motorcycle taxi operators wear orange vests with yellow number plates. The driving license with photo and driver's details in form of yellow card is placed on the back of the driver where the passenger can see clearly. In compliance with Thailand's motorcycle helmet law, many (but not all) drivers carry a spare helmet to offer to passengers. Bangkok locals generally only use motorcycle taxis when they need to get somewhere fast, as metered taxi-cabs can not only be more expensive for short trips but also slower than flat-rate motorcycles. Therefore, motorcycle taxi-drivers in Bangkok have built their reputation on delivering service as quickly as possible and tend to drive very fast and weave through traffic.
United Kingdom
Motorcycle taxi service in London began in 1990 as a niche industry. All equipment is provided for the passenger, along with an intercom system linking the rider and passenger. The motorcycles have racks that can hold a carry-on suitcase, for trips to local airports, especially Stansted, Gatwick, and City. The bikes are now licensed by Transport for London and the Public Carriage Office, which also license London's black cabs.
United States
Moto Limos Club, a motorcycle for-hire service, started in California and New York City in 2011. As of 2012, the business filing was not renewed and of 2015 the filing was considered suspended. Passengers were not able to hail the motorcycles on the street; instead, a yearly individual or corporate membership fee is charged, plus an hourly rate. Experienced riders, many former Police motorcycle riders, carried clients on Honda Gold Wings, and in California, can bypass traffic congestion by lane splitting. Passengers were provided with helmets, airbag vests, and in-helmet, Bluetooth cell phones. The service also bought several Can-Am Spyders, before realizing they were not capable of splitting lanes.
Vietnam
Nimble motorcycle taxis, which surpass buses in speed and mobility, comprise one of the most popular modes of transportation in Vietnam, where they are known as xe ôm. Passengers can get a ride via mobile app or by hailing passing operators, or by finding drivers who gather at public places such as schools, markets, hospitals, and bus and train stations.
Before the rise in popularity of ride-hailing apps, motorcycle taxi driving was a mostly informal economy, although some unions existed. Fare is verbally agreed upon before the trip based on distance. Some informal motorcycle taxi drivers still exist, as well as drivers working for regulated ride-hailing companies who would take on ad-hoc trips not booked through the app.
Wearing a helmet on motorcycles is required by Vietnamese laws for both drivers and passengers, as such motorcycle taxi drivers would provide helmet for their customers.
Go-Viet had a 35% market share among motorbike vehicle for hire companies in Ho Chi Minh City just six weeks after launching there on August 1, 2018, according to Go-Jek founder and chief executive Nadiem Makarim.
|
Technology
|
Motorized road transport
| null |
4048154
|
https://en.wikipedia.org/wiki/Si-o-se-pol
|
Si-o-se-pol
|
The Allahverdi Khan Bridge (), popularly known as Si-o-se-pol (), is the largest of the eleven historical bridges on the Zayanderud, the largest river of the Iranian Plateau, in Isfahan, Iran.
The bridge was built in the early 17th century to serve as both a bridge and a dam.
History
Si-o-se-pol was built between 1599 and 1602, under the reign of Abbas the Great, the fifth shah of Safavid Iran. It was constructed under the supervision of Allahverdi Khan Undiladze, the commander-in-chief of the armies, who was of Georgian origin, and was also named after him. The bridge served particularly as a connection between the mansions of the elite, as well as a link to the city's vital Armenian neighborhood of New Julfa.
In years of drought (2000–02 and 2013), the river was dammed upstream to provide water for Yazd province.
Structure
The bridge has a total length of and a total width of . It is a vaulted arch bridge consisting of two superimposed rows of 33 arches, from whence its popular name of Si-o-se-pol comes, and is made of stone. The longest span is about . The interior of Si-o-se-pol was originally decorated with paintings, which were often described by travelers as erotic.
Gallery
Transportation
Chaharbagh Street
Motahari Street
Kamaloddin Esmaeil Street
Chahar Bagh Bala Street
Mellat Street
Ayenekhaneh Street
Enqelab Metro Station
Si-o-se Pol Metro Station
|
Technology
|
Bridges
| null |
4050647
|
https://en.wikipedia.org/wiki/Pandanaceae
|
Pandanaceae
|
Pandanaceae is a family of flowering plants native to the tropics and subtropics of the Old World, from West Africa to the Pacific. It contains 982 known species in five genera, of which the type genus, Pandanus, is the most important, with species like Pandanus amaryllifolius and karuka (Pandanus julianettii) being important sources of food. The family likely originated during the Late Cretaceous.
Characteristics
Pandanaceae includes trees, shrubs, lianas, vines, epiphytes, and perennial herbs. Stems may be simple or bifurcately branched, and may have aerial prop roots. The stems bear prominent leaf scars. The leaves are very long and narrow, sheathing, simple, undivided, with parallel veins; the leaf margins and abaxial midribs are often prickly.
The plants are dioecious. The inflorescences are terminally borne racemes, spikes or umbels, with subtended spathes, which may be brightly colored. The flowers are minute and lack perianths. Male flowers contain numerous stamens with free or fused filaments. Female flowers have a superior ovary, usually of many carpels in a ring, but may be reduced to a row of carpels or a single carpel. Fruits are berries or drupes, usually multiple.
Pandanaceae includes five genera: Benstonea, Freycinetia, Martellidendron, Pandanus, and Sararanga. Benstonea (as subgenus "Acrostigma") and Martellidendron were formerly considered subgenera of Pandanus, but were recognized as distinct genera based on DNA sequencing.
Uses
Particular species of Pandanus are used to make mats (e.g. Central Africa) or in food products (e.g. leaves as flavoring, or fruit in Southeast Asia).
|
Biology and health sciences
|
Pandanales
|
Plants
|
7059576
|
https://en.wikipedia.org/wiki/Back-arc%20basin
|
Back-arc basin
|
A back-arc basin is a type of geologic basin, found at some convergent plate boundaries. Presently all back-arc basins are submarine features associated with island arcs and subduction zones, with many found in the western Pacific Ocean. Most of them result from tensional forces, caused by a process known as oceanic trench rollback, where a subduction zone moves towards the subducting plate. Back-arc basins were initially an unexpected phenomenon in plate tectonics, as convergent boundaries were expected to universally be zones of compression. However, in 1970, Dan Karig published a model of back-arc basins consistent with plate tectonics.
Structural characteristics
Back-arc basins are typically very long and relatively narrow, often thousands of kilometers long while only being a few hundred kilometers wide at most. For back-arc extension to form, a subduction zone is required, but not all subduction zones have a back-arc extension feature. Back-arc basins are found in areas where the subducting plate of oceanic crust is very old. The restricted width of back-arc basins is due to magmatic activity being reliant on water and induced mantle convection, limiting their formation to along subduction zones. Spreading rates vary from only a few centimeters per year (as in the Mariana Trough), to 15 cm/year in the Lau Basin. Spreading ridges within the basins erupt basalts that are similar to those erupted from the mid-ocean ridges; the main difference being back-arc basin basalts are often very rich in magmatic water (typically 1–1.5 weight % H2O), whereas mid-ocean ridge basalt magmas are very dry (typically <0.3 weight % H2O). The high water contents of back-arc basin basalt magmas is derived from water carried down the subduction zone and released into the overlying mantle wedge. Additional sources of water could be the eclogitization of amphiboles and micas in the subducting slab. Similar to mid-ocean ridges, back-arc basins have hydrothermal vents and associated chemosynthetic communities.
Seafloor spreading
Evidence of seafloor spreading has been seen in cores of the basin floor. The thickness of sediment that collected in the basin decreased toward the center of the basin, indicating a younger surface. The idea that thickness and age of sediment on the sea floor is related to the age of the oceanic crust was proposed by Harry Hess. Magnetic anomalies of the crust that had formed in back-arc basins deviated in form from the crust formed at mid-ocean ridges. In many areas the anomalies do not appear parallel, as well as the profiles of the magnetic anomalies in the basin lacking symmetry or a central anomaly as a traditional ocean basin does, indicating asymmetric seafloor spreading.
This has prompted some to characterize the spreading in back-arc basins to be more diffused and less uniform than at mid-ocean ridges. The idea that back-arc basin spreading is inherently different from mid-ocean ridge spreading is controversial and has been debated through the years. Another argument put forward is that the process of seafloor spreading is the same in both cases, but the movement of seafloor spreading centers in the basin causes the asymmetry in the magnetic anomalies. This process can be seen in the Lau back-arc basin. Though the magnetic anomalies are more complex to decipher, the rocks sampled from back-arc basin spreading centers do not differ very much from those at mid-ocean ridges. In contrast, the volcanic rocks of the nearby island arc differ significantly from those in the basin.
Back-arc basins are different from normal mid-ocean ridges because they are characterized by asymmetric seafloor spreading, but this is quite variable even within single basins. For example, in the central Mariana Trough, current spreading rates are 2–3 times greater on the western flank, whereas at the southern end of the Mariana Trough the position of the spreading center adjacent to the volcanic front suggests that overall crustal accretion has been nearly entirely asymmetric there. This situation is mirrored to the north where a large spreading asymmetry is also developed.
Other back-arc basins such as the Lau Basin have undergone large rift jumps and propagation events (sudden changes in relative rift motion) that have transferred spreading centers from arc-distal to more arc-proximal positions. Conversely, study of recent spreading rates appear to be relatively symmetric with perhaps small rift jumps. The cause of asymmetric spreading in back-arc basins remains poorly understood. General ideas invoke asymmetries relative to the spreading axis in arc melt generation processes and heat flow, hydration gradients with distance from the slab, mantle wedge effects, and evolution from rifting to spreading.
Formation and tectonics
The extension of the crust behind volcanic arcs is believed to be caused by processes in association with subduction. As the subducting plate descends into the asthenosphere it sheds water, causing mantle melting, volcanism, and the formation of island arcs. Another result of this is a convection cell is formed. The rising magma and heat along with the outwards tension in the crust in contact with the convection cell cause a region of melt to form, resulting in a rift. This process drives the island arc toward the subduction zone and the rest of the plate away from the subduction zone. The backward motion of the subduction zone relative to the motion of the plate which is being subducted is called trench rollback (also known as hinge rollback or hinge retreat). As the subduction zone and its associated trench pull backward, the overriding plate is stretched, thinning the crust and forming a back-arc basin. In some cases, extension is triggered by the entrance of a buoyant feature in the subduction zone, which locally slows down subduction and induces the subducting plate to rotate adjacent to it. This rotation is associated with trench retreat and overriding plate extension.
The age of the subducting crust needed to establish back-arc spreading has been found to be 55 million years old or older. This is why back-arc spreading centers appear concentrated in the western Pacific. The dip angle of the subducting slab may also be significant, as is shown to be greater than 30° in areas of back-arc spreading; this is most likely because as oceanic crust gets older it becomes denser, resulting in a steeper angle of descent.
The thinning of the overriding plate from back-arc rifting can lead to the formation of new oceanic crust (i.e., back-arc spreading). As the lithosphere stretches, the asthenosphere below rises to shallow depths and partially melts as a result of adiabatic decompression melting. As this melt nears the surface, spreading begins.
Sedimentation
Sedimentation is strongly asymmetric, with most of the sediment supplied from the active volcanic arc which regresses in step with the rollback of the trench. From cores collected during the Deep Sea Drilling Project (DSDP) nine sediment types were found in the back-arc basins of the western Pacific. Debris flows of thick to medium bedded massive conglomerates account for 1.2% of sediments collected by the DSDP. The average size of the sediments in the conglomerates are pebble sized but can range from granules to cobbles. Accessory materials include limestone fragments, chert, shallow water fossils and sandstone clasts.
Submarine fan systems of interbedded turbidite sandstone and mudstone made up 20% of the total thickness of sediment recovered by the DSDP. The fans can be divided into two sub-systems based on the differences in lithology, texture, sedimentary structures, and bedding style. These systems are inner and midfan subsystem and the outer fan subsystem. The inner and midfan system contains interbedded thin to medium bedded sandstones and mudstones. Structures that are found in these sandstones include load clasts, micro-faults, slump folds, convolute laminations, dewatering structures, graded bedding, and gradational tops of sandstone beds. Partial Bouma sequences can be found within the subsystem. The outer fan subsystem generally consists of finer sediments when compared to the inner and midfan system. Well sorted volcanoclastic sandstones, siltstones and mudstones are found in this system. Sedimentary structures found in this system include parallel laminae, micro-cross laminae, and graded bedding. Partial Bouma sequences can be identified in this subsystem.
Pelagic clays containing iron-manganese micronodules, quartz, plagioclase, orthoclase, magnetite, volcanic glass, montmorillonite, illite, smectite, foraminiferal remains, diatoms, and sponge spicules made up the uppermost stratigraphic section at each site it was found. This sediment type consisted of 4.2% of the total thickness of sediment recovered by the DSDP.
Biogenic pelagic silica sediments consist of radiolarian, diatomaceous, silicoflagellate oozes, and chert. It makes up 4.3% of the sediment thickness recovered. Biogenic pelagic carbonates is the most common sediment type recovered from the back-arc basins of the western Pacific. This sediment type made up 23.8% of the total thickness of sediment recovered by the DSDP. The pelagic carbonates consist of ooze, chalk, and limestone. Nanofossils and foraminifera make up the majority of the sediment. Resedimented carbonates made up 9.5% of the total thickness of sediment recovered by the DSDP. This sediment type had the same composition as the biogenic pelagic carbonated, but it had been reworked with well-developed sedimentary structures. Pyroclastics consisting of volcanic ash, tuff and a host of other constituents including nanofossils, pyrite, quartz, plant debris, and glass made up 9.5% of the sediment recovered. These volcanic sediments were sourced form the regional tectonic controlled volcanism and the nearby island arc sources.
Locations
Active back-arc basins are found in the Marianas, Kermadec-Tonga, South Scotia, Manus, North Fiji, and Tyrrhenian Sea regions, but most are found in the western Pacific. Not all subduction zones have back-arc basins; some, like the central Andes, are associated with rear-arc compression.
There are a number of extinct or fossil back-arc basins, such as the Parece Vela-Shikoku Basin, Sea of Japan, and Kurile Basin. Compressional back-arc basins are found, for example, in the Pyrenees and the Swiss Alps.
History of thought
With the development of plate tectonic theory, geologists thought that convergent plate margins were zones of compression, thus zones of strong extension above subduction zones (back-arc basins) were not expected. The hypothesis that some convergent plate margins were actively spreading was developed by Dan Karig in 1970, while a graduate student at the Scripps Institution of Oceanography. This was the result of several marine geologic expeditions to the western Pacific.
|
Physical sciences
|
Tectonics
|
Earth science
|
6905166
|
https://en.wikipedia.org/wiki/Shimeji
|
Shimeji
|
Shimeji (Japanese: , or ) is a group of edible mushrooms native to East Asia, but also found in northern Europe. Hon-shimeji (Lyophyllum shimeji) is a mycorrhizal fungus and difficult to cultivate. Other species are saprotrophs, and buna-shimeji (Hypsizygus tessulatus) is now widely cultivated. Shimeji is rich in umami-tasting compounds such as guanylic acid, glutamic acid, and aspartic acid.
Species
Several species are sold as shimeji mushrooms. All are saprotrophic except Lyophyllum shimeji.
Mycorrhizal
Hon-shimeji (), Lyophyllum shimeji
The cultivation methods have been patented by several groups, such as Takara Bio and Yamasa, and the cultivated hon-shimeji is available from several manufacturers in Japan.
Saprotrophic
Buna-shimeji (, lit. beech shimeji), Hypsizygus tessulatus, also known in English as the brown beech or brown clamshell mushroom.
Hypsizygus marmoreus is a synonym of Hypsizygus tessulatus. Cultivation of Buna-shimeji was first patented by Takara Shuzo Co., Ltd. in 1972 as hon-shimeji and the production started in 1973 in Japan. Now, several breeds are widely cultivated and sold fresh in markets.
Bunapi-shimeji (), known in English as the white beech or white clamshell mushroom.
Bunapi was selected from UV-irradiated buna-shimeji ('hokuto #8' x 'hokuto #12') and the breed was registered as 'hokuto shiro #1' by Hokuto Corporation.
Hatake-shimeji (), Lyophyllum decastes.
Shirotamogidake (), Hypsizygus ulmarius.
These two species had been also sold as hon-shimeji.
Velvet pioppino (alias velvet pioppini, black poplar mushroom, Chinese: /), Agrocybe aegerita.
Shimeji health benefits
Shimeji mushrooms contain minerals like potassium and phosphorus, magnesium, zinc, and copper. Shimeji mushrooms lower the cholesterol level of the body. This mushroom is rich in glycoprotein (HM-3A), marmorin, beta-(1-3)-glucan, hypsiziprenol, and hypsin therefore is a potential natural anticancer agent. Shimeji mushrooms contain angiotensin I-converting enzyme (ACE) inhibitor which is an oligopeptide that may be helpful in lowering blood pressure and reducing the risk of stroke in persons having hypertension. Also rich in polysaccharides, phenolic compounds, and flavonoids. Therefore, inhibits inflammatory cytokines and oxidative stress and protects from lung failure. These compounds also help in reducing oxidative stress-mediated disease through radical scavenging activity hence these mushrooms are antioxidants also.
Culinary Use
Shimeji should always be cooked: it is not a good mushroom to serve raw due to a somewhat bitter taste, but the bitterness disappears completely upon cooking. The cooked mushroom has a pleasant, firm, slightly crunchy texture and a slightly nutty flavor. Cooking also makes this mushroom easier to digest. It works well in stir-fried foods like stir-fried vegetables, as well as with wild game or seafood. Also, it can be used in soups, stews, and in sauces. When cooked alone, Shimeji mushrooms can be sautéed whole, including the stem or stalk (only the very end cut off), using a higher temperature or they can be slow roasted at a low temperature with a small amount of butter or cooking oil. Shimeji is used in soups, nabe and takikomi gohan.
|
Biology and health sciences
|
Edible fungi
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Plants
|
9174535
|
https://en.wikipedia.org/wiki/Aquaculture%20of%20tilapia
|
Aquaculture of tilapia
|
Tilapia has become the third most important fish in aquaculture after carp and salmon; worldwide production exceeded in 2002 and increases annually. Because of their high protein content, large size, rapid growth (6 to 7 months to grow to harvest size), and palatability, a number of coptodonine and oreochromine cichlids—specifically, various species of Coptodon, Oreochromis, and Sarotherodon—are the focus of major aquaculture efforts.
Tilapia fisheries originated in Africa and the Levant. The accidental and deliberate introductions of tilapia into South and Southeast Asian freshwater lakes have inspired outdoor aquaculture projects in various countries with tropical climates, including Honduras, Papua New Guinea, the Philippines, and Indonesia. Tilapia farm projects in these countries have the highest potential to be "green" or environmentally friendly. In temperate zone localities, tilapia farmers typically need a costly energy source to maintain a tropical temperature range in their tanks. One relatively sustainable solution involves warming the tank water using waste heat from factories and power stations.
Tilapiines are among the easiest and most profitable fish to farm due to their omnivorous diet, mode of reproduction (the fry do not pass through a planktonic phase), tolerance of high stocking density, and rapid growth. In some regions the fish can be raised in rice fields at planting time and grow to edible size () when the rice is ready for harvest. Unlike salmon, which rely on high-protein feeds based on fish or meat, commercially important tilapiine species eat a vegetable or cereal-based diet.
Tilapia raised in inland tanks or channels are considered safe for the environment, since their waste and disease is contained and not spread to the wild. However, tilapiines have acquired notoriety as being among the most serious invasive species in many subtropical and tropical parts of the world. For example, blue tilapia (Oreochromis aureus) (itself commonly confused with another species often used in aquaculture, the Nile tilapia, O. niloticus), Mozambique tilapia (O. mossambicus), blackchin tilapia (Sarotherodon melanotheron), spotted tilapia (Pelmatolapia mariae), and redbelly tilapia (Coptodon zillii) have all become established in the southern United States, particularly in Florida and Texas.
Commercially grown tilapia are almost exclusively male. Being prolific breeders, female tilapia in the ponds or tanks will result in large populations of small fish. Whole tilapia can be processed into skinless, boneless (PBO) fillets: the yield is from 30% to 37%, depending on fillet size and final trim.
Commercial breeding of Nile tilapia
Although farming of Tilapia has been going on for thousands of years, the breeding of Tilapia did not start until recently. The first breeding program started in 1988 in a collaboration between the international center for living aquatic resources (ICLARM or WorldFish) and Akvaforsk. The name of the project was GIFT, meaning genetically improved farmed tilapia. Four wild strains from Africa were crossed with four farmed strains from the Philippines. This strain is currently farmed in more than 87 countries in Asia, Africa and Latin America.
The GIFT strain is used in two selection programs, one of them being GenoMar, a subsidiary EW Group. In the past the absolute and only important trait when breeding tilapia was growth, being the only criteria for selection. Today more traits have been added into the selection criteria, like growth, fillet yield, robustness and specific disease resistance. Robustness is one of those traits that is becoming more important since it is the biggest problem with mortality on farms today. GenoMar has successfully had a growth increase of 7% per generation while fillet yield only improves with 0,3% per generation. The explanation for this is its low heritability together with the fact that the trait cannot be measured on live animals and therefore information of fillet yield is given from relatives instead.
Breeding of Tilapia is done with the help of a pyramid scheme with multiplying generations. The goal with this is that a few high merit individuals can be passed down into billions of production fish at the farms. The generation interval today is down to only 6-9 months meaning that there can be more than one generation per year. Mass selection and pedigree-based selection are the most used methods today for genetic improvements of tilapias. The breeding program GenoMar has used marker-assisted selection since 2004 using microsatellites when doing parentage assignment has been done on Tilapia. Since 2019 genomic selection using single nucleotide polymorphic (SNP) has been used more widely.
The latest genome assembly is from 3 years ago, and can be seen from the name of the assembly that NMBU was also highly involved in the effort along with the University of Maryland. Nile tilapia have 22 pairs of chromosomes. 23 Linkage groups because of the sex chromosomes. About 1 billion base pairs in length, 3,010 contigs made 2,460 scaffolds which were placed at a chromosome level as the karyotype was already known. The reference genome also has the non-nuclear mitochondrial genome. With help from bioinformatics, the estimated number of genes is around 30 thousand. It can be browsed in ensembl or NCBI for example.
The essential technological foundation for genomic selection is not obtaining the pedigree but the genotypes of the animals. This is currently done by SNP chips, oligonucleotide arrays. They have to be specifically designed for a species and commonly that is done based after the whole genome sequence has been obtained. Only some parts of the WGS are of interest, namely those that exhibit variation. Dense markers are considered good enough to capture the gene content because they are in linkage disequilibrium with the genes that influence the phenotype, or as they are called QTL. There are three major SNP chips for Tilapia, which were announced in 2018, 2020 and then 2020 again. In RNA Seq, the RNA from cells of a tissue is extracted and they are sequenced in order to know what genes are being expressed and at what intensities. First, the extracted RNA is converted into cDNA and that cDNA library is sequenced using the same machines used in whole genome sequencing. The bioinformatics pipeline afterwards is different from WGS, though. Since the segments are shorter, alignment is not as difficult. Also, one is interested in the amount of transcription that is happening. In any case, RNA Seq provides valuable insight into the biology of a group of cells and the entire organism.
In the beginning, breeding programs focused mainly on growth traits. Nowadays, more traits are included in the breeding goal. The tendency is to have even more traits in the future. For example, disease resistance, reproductive traits, robustness, lower emissions, feed conversion ratio (sustainability traits). New technologies for high-throughput phenotyping, as in the concept of precision farming, mean that many novel traits might be included as well. There is already a tendency to have mergers and acquisitions, with a few companies buying smaller ones, just like it happened in the poultry industry. Also like the poultry industry, the exploitation of heterosis is a possibility that could be established in Tilapia breeding. This would mean more protection for the companies and attract more corporate enterprises. Because crossbreeding provides a biological lock mechanism. Gene editing is coming. Especially CRISPR-Cas9 can already be implemented and holds a lot of promise. We also expect for the production systems to become ever more intensive. This means fewer ponds, more cages and more RAS. Overall, the average fish density is going to increase.
Nutritional value
Tilapia from aquaculture contain especially high ratios of omega-6 to omega-3 fatty acids.
Around the world
Apart from the very few species found in the Western Asia, such as the Middle Eastern mango tilapia, there are no tilapia cichlids native to Asia. However, species originally from Africa have been widely introduced and have become economically important as food fish in many countries. China, the Philippines, Taiwan, Indonesia, and Thailand are the leading suppliers, and these countries altogether produced about of fish in 2001, constituting about 76% of the total aquaculture production of tilapia worldwide.
Other countries
India
The FAO has not recorded any production of farmed tilapia by India. Rajiv Gandhi Centre for Aquaculture (RGCA), the R&D arm of Marine Products Export Development Authority, has established a facility in Vijayawada to produce mono-sex tilapia in two strains. This project involves the establishment of a satellite nucleus for the GIFT strain of tilapia in India, the design and conduct of a genetic improvement program for this strain, the development of dissemination strategies, and the enhancement of local capacity in the areas of selective breeding and genetics. The development and dissemination of a high yielding tilapia strain possessing desirable production characteristics is expected to bring about notable economic benefits for the country. Farming of Tilapia is not permitted in the country on commercial basis. The Rajiv Gandhi Center for Aquaculture (RGCA) has expressed interest in obtaining the Genetically Improved Farmed Tilapia (GIFT strain) for aquaculture development in the country. The GIFT tilapia strain, selectively bred in Malaysia and the Philippines, has achieved an improvement of more than 10 per cent per generation in growth rate and has been widely distributed to several Asian countries and to Latin America (Brazil). However, rather than passively importing the improved genetic stock, the Center is interested in running a formal breeding program (fully pedigreed population) similar to the one that has been carried out for the GIFT strain in Malaysia.
The aim is to produce fast-growing high yielding tilapia strains adapted to a wide range of local farming environments that can be grown at as low a cost as possible.
The project involves several steps. The first is the establishment of a new nucleus of the GIFT strain at the RGCA and the design of a formal breeding program to further improve its genetic performance within the local environment. This will involve enhancing the capacity of local personnel in selective breeding, genetic improvement, statistical analysis and hatchery management through specialized training courses.
Once a high performing tilapia strain (or strains) has been developed, the establishment of satellite hatcheries will increase the availability and decrease the costs of seed stock. These public and private hatcheries will act as multipliers for the superior genetics developed at RGCA and the sites for dissemination of quality broodstock to fish farmers.
Although the ultimate target groups of this project are fish farmers and small householders, a wider range of beneficiaries is expected, including commercial producers, scientists and the end consumers. The RGCA will gain experience and knowledge on the development of genetic improvement programs for economically important traits and other aspects of modern quantitative genetics. This experience and the development of a standard selective breeding protocol will allow for genetic improvement programs for other aquaculture species that are commonly cultured in India. Hatchery managers, producers and farmers will also improve their capacity to implement on-farm selective breeding programs.
In the longer term the project is also expected to contribute to the development of a complete chain of production. This will require initial capital support for farmers, identification of alternative cheap plant-based feed, and diagnosis of diseases in hatcheries, as well as strategies for early growth management. Improvement in harvest technologies, including storage of product and transport facilities, is likely to improve as a consequence of this project.
Malawi
In 2010 Malawi produced 2,997 tonnes of farmed tilapia. A few species of Oreochromis tilapia, popular known as 'chambo', are the most popular fish in Malawi. They are endemic to bodies of water in Malawi like Lake Malawi, Lake Malombe and the Shire River. Due to over fishing, the fish however is now on the threatened species list. Malawi has fish farms that are dedicated to farming tilapia.
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Technology
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Aquaculture
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10674423
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https://en.wikipedia.org/wiki/Taobao
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Taobao
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Taobao is a Chinese online shopping platform. It is headquartered in Hangzhou and is owned by Alibaba. According to Alexa rank, it was the eighth most-visited website globally in 2021. Taobao.com was registered on April 21, 2003 by Alibaba Cloud Computing (Beijing) Co., Ltd.
Taobao Marketplace facilitates consumer-to-consumer retail by providing a platform for small businesses and individual entrepreneurs to open online stores that mainly cater to consumers in Chinese-speaking regions (Mainland China, Hong Kong, Macau and Taiwan) and abroad, which is made payable by online accounts. Its stores usually offer an express delivery service.
Sellers are able to post goods for sale either through a fixed price or an auction. Auctions make up a small percentage of transactions, whereas the majority of the products are new merchandise sold at fixed prices. Taobao users usually read feedback and compare items from multiple shops. Taobao's popular payment platform is Alibaba's Alipay
As of at least 2024, it is the world's most popular shopping hub as measured by gross merchandise value.
History
Before its launch of Taobao, Alibaba had focused on online business-to-business wholesale sales.
In 2003, eBay acquired Eachnet, China's online auction leader at the time, for US$180 million. It became a major contender in the Chinese consumer e-commerce market.
Responding to eBay's moves Alibaba launched Taobao as a rival consumer-to-consumer platform. To counter eBay's expansion, Taobao offered free listings to sellers. It introduced instant messaging for facilitating buyer-seller communication and an escrow-based payment tool: Alipay. Taobao's focus on institutional trust building mechanisms like escrowing payments became a major reason for its success in the market for eBay, despite eBay's first-mover advantage. Taobao became mainland China's market leader within two years. Its market share grew from 8% to 59% between 2003 and 2005, while eBay China dropped from 79% to 36%. eBay shut down its Chinese site in 2006.
In 2008, Taobao established a platform rule providing that customers had the right to return clothes sold on the platform within seven days of receipt without cause, and subsequently expanded the rule to cover other commodities. This rule became an influential standard in Chinese e-commerce and in 2014 was made an industry standard through the State Administration for Industry and Commerce's Administrative Measures for Online Trading.
In October 2010, Taobao beta-launched eTao as an independent search engine for online shopping to provide and merchant information from a number of major consumer e-commerce websites in China. Online shoppers would be able to use the site to compare prices across sellers. According to the Alibaba Group web site, eTao offers products from Amazon China, Dangdang, Gome, Yihaodian, Nike China and Vancl, as well as Taobao and Tmall.
In June 2011, Jack Ma, executive chairman and former chief executive officer of Alibaba Group, announced that Taobao would split into three different companies: Taobao Marketplace (a consumer-to-consumer platform), Tmall.com (a business-to consumer platform, then called Taobao Mall), and eTao (a search engine for online shopping). The move was said to be necessary for Taobao to “meet competitive threats that emerged in the past two years during which the Internet and e-commerce landscape has changed dramatically.”
In 2012 Taobao began to accept international Visa and MasterCard credit and debit cards.
On 29 April 2013, Alibaba announced an investment of US$586 million in Sina Weibo. According to Reuters, the deal “should drive more web traffic to Alibaba's Taobao Marketplace”. On August 1, 2013, Alibaba launched Weibo for Taobao, which allows users to link Sina Weibo accounts with Taobao accounts.
In addition to hosting individuals and businesses, Taobao includes online stores for courts, customs offices, state-owned banks, and asset management companies selling distressed assets. By early 2014, more than 500 local Chinese courts had established Taobao store fronts to sell seized property, including property which had been confiscated as part of the anti-corruption campaign under Xi Jinping.
Features
Shop feedback
A good way to investigate a Taobao shop is by clicking the shop's rating icon. For Tmall.com shops, people click the stars to view their ratings. Taobao users usually read feedback and compare items from multiple shops. Feedback can be genuine or artificial, requiring users to make their own judgments. Feedback can be posted by competitors.
Every trade deal includes a section of customer feedback. Shop owners often put effort to maximize positive comments. Negotiations may happen between sellers and consumers over their satisfaction ratings.
Taobao uses search tools and other functions to understand user demands. Customers are asked to complete surveys that ask:
Obstacles encountered
Advice and reviews
Use frequency
Importance of that particular product
Satisfaction levels about specific aspects, including visual and typographic layout, procedure and instructions
Overall satisfaction
Other features
Taobao Marketplace offers various features and services to create a better user experience for online shoppers and retailers. In January 2010, it launched the Taobao app, created by independent developers through the Taobao Open Platform, to be downloaded by consumers in Taobao App Store.
In March 2010, it introduced the Taobao Data Cube platform, which gives small businesses access to its aggregate consumer transactions data for insight into industry trends.
In June 2010, it partnered with Wasu Media Internet Limited to launch Taohua, a digital entertainment products platform, and interactive digital television shopping, that are operated by a joint-venture formed by the two companies.
Weitao
Weitao is a private shopping assistant/blog for Taobao/Tmall customers. It is a micro-blogging feature for brands and merchants on its e-commerce sites Taobao and Tmall.
Taobao General Code
Taobao has developed an extensive set of rules and a constitution which it terms the "General Code". The General Code consists of 6 chapters and 31 provisions proscribing the basic access requirements and obligations of users, seller obligations, and the platform's conflict resolution mechanism.
When Taobao proposes a rule change, all buyers and sellers with a sufficiently high Zhima credit score can vote and express their opinions on the rule. Taobao also invites professionals and academics with relevant expertise to public evaluate proposed rule changes in order to inform voters.
Public jury
Alibaba established its public jury (pan.taobao.com) dispute resolution system in 2012. By 2020, it was a widely-used dispute resolution tool on the main Taobao platform and was also frequently used on Xianyu (Taobao's used goods platform).
Through the public jury process, Taobao randomly selects panels of 13 jurors (termed "public assessors" on Taobao) from a pool of 4 million volunteers. Candidates must have been on Taobao for at least a year and have sufficiently high Sesame Credit ratings. Volunteers earn experience points that can earn virtual titles and which can be "spent" for Taobao to make a donation to charity.
All participants in the public jury process are anonymized and no communication between or among the disputing parties and the jurors are permitted. Jurors review the case and vote within 48 hours. The party with the most votes wins. A party who is unsatisfied with the jury outcome can request further review by Taobao employees. Taobao can implement jury decisions through means including freezing payments, taking money from a sellers' store deposit, lowering user ratings, or removing a party from the platform.
Most public jury cases involve buyer-seller disputes. In some instances, Taobao has used large juries of 800 to 1000 jurors to decide issues relating to platform governance. For example, Taobao used a large jury to decide whether to allow a baby bottle manufacturer, Betta, to remain on the platform. Betta was a legal but copycat style product of the popular Japanese brand Doctor Betta, which was also sold on Taobao. Jurors voted to remove the copycat product from the platform.
Golden Cudgel
In 2019, Taobao launched a dispute resolution called Golden Cudgel, named after the monkey king's magical weapon in the 16th century novel Journey to the West. This mechanism allows sellers who have passed qualifying exams to remove a limited number of malicious reviews on a daily basis without prior permission from the platform. Sellers must submit evidence to establish the dishonest nature of each removed review to enable review by the platform. Sellers' ability to use the Golden Cudgel mechanism is revoked if they are found by the platform to have repeatedly removed reviews improperly.
Services
Alipay
Launched in 2004, Alipay () is an escrow-based online payment platform. It is the preferred payment solution for Taobao Marketplace. It is the most widely used third-party online payment solution in China. To ensure safe transactions, Alipay uses an escrow system through which payment is only released to the seller once the buyer has received goods in satisfactory condition. According to the Alibaba Group website, Alipay partners with multiple financial institutions as well as Visa and MasterCard to facilitate payments in China and abroad.
At the time it was implemented, the mandatory escrow feature of Alipay was a major institutional innovation for e-commerce platforms. This was a major reason Taobao was able to outcompete eBay/EachNet in the Chinese market.
Alipay systems are separate for different groups of users. For instance, Alipay users may send and receive funds if they have an account that have a credit card issued in China, whereas users with other cards may only use Alipay to pay for goods or services from Taobao. This has proven problematic for international users, as they are unable to receive refunds not issued via the Taobao system.
AliExpress
AliExpress was created in April 2010 as an international retailing website. People who live overseas can use the service to purchase items from Chinese manufacturers online.
AliWangWang (TradeManager)
Taobao Marketplace allows buyers and sellers to communicate prior to the purchase through its embedded proprietary instant chat program, named AliWangWang ().
Baopals
In February 2016, 3 expats living in Shanghai launched Baopals, a shopping platform that translates Taobao and Tmall into English so that foreigners living in China can access of its products and services. Over 2.4 million items have been sold on the platform.
Happy Taobao
In Dec. 2009, Taobao, together with Hunan TV, set up Happy Taobao, Inc for television shopping. Hunan TV launched an entertainment series called "Happy Taobao", while Taobao Marketplace created channels and independent websites.
Taobao Live
In 2018, Alibaba launched the streaming service named Alibaba Live. This service was created with the goal of allowing online retailers to market their products utilizing social shopping. This has seen significant growth in popularity and success, with the 84 stores using this service reporting $7.4 million in 2020 sales. Taobao stated that they predict live-streaming on their platform will generate over 500 billion sales transactions. Taobao Live now has over 10,000 weblebrities promoting a wide range of items including as cosmetics, apparel, cuisine, and numerous electrical gadgets. Taobao Live's daily sales have already surpassed $3 billion.
Alibaba promotes a new style of live streaming, called cūnbō (村播), that features rural sellers. Taobao has given them their own category in the app, with the purpose of making it easier for these rural sellers to find customers and followers on the platform.
Singles' Day
Singles' Day (also known as the Double eleven shopping carnival, as in 11/11) is the largest Chinese online shopping day. It takes place on 11 November each year. It takes the advantages of the Chinese singles day that was created by Chinese university students to celebrate their bachelordom. After the event was launched, it obtained widespread attention, attracting other e-commerce companies to imitate this model.
Singles day grew rapidly since its introduction in 2009. 2009 sales reached RMB50 million (£5.68 million): Sales grew rapidly thereafter:
2009: RMB50 million (£5.68 million)
2010: RMB900 million (£102 million)
2011: RMB3.4 billion (£386 million)
2012: RMB19.1 billion (£2.17 billion)
2013: RMB35 billion (£3.97 billion)
2015: RMB91.2 billion
2016: RMB120.7 billion
2017: RMB168.2 billion
2018: RMB213.5 billion
2019: RMB268.4 billion
In 2016, Alibaba introduced the T-mall double eleven party, inviting celebrities who took part in a Victoria's Secret show. At the 2017 party, Jack Ma launched his film Gong Shou Dao (Defend the Homeland with Kungfu).
Because of the huge trading volume and income in Singles Day, Taobao launched another promotional activity on December 12 (12/12), drove record trading every year thereafter.
Technology
Anti-fraud
Taobao has a five layer system for fraud detection. "Account check" is the first layer: during this stage, automatic processes examine whether the account at issue has demonstrated suspicious activity. Fraud cases deemed obvious at this layer are declined. Taobao's system can also require further information and submit the transaction to the next three layers of automatic review: device check, activity check, and risk strategy. Each check sends fraud cases deemed obvious to an automatic decision and refers potential no-obvious fraud to the next level. These automated anti-fraud checks use big data models, including analysis of user behavioral data, network data, delivery details, and IP addresses. The final level is manual review by Taobao employees.
Taobao shares information with police and local courts to assist in locating sellers alleged to be selling counterfeit products. For example, in 2014, collaboration with law enforcement resulted in 1,000 counterfeit cases, 400 arrests, and the shutdown of 200 related physical stores, warehouses, and factories.
Markets
Taobao for Southeast Asia
In September 2013, Taobao launched its Southeast Asian site. A translation feature is available for major languages in Southeast Asia. In September 2024, Taobao launched an English version of its app tailored specifically for users in Singapore.
Controversies
Taobao has sometimes been the subject of in-person and online seller protests following major changes to its rules. The largest seller protest was the 2011 "October Rising". With the goal of reducing counterfeits and substandard products, Taobao had increased the Taobao Mall membership fees for sellers and their required cash deposits. The rule changes were made without warning. Approximately 50,000 sellers formed the "anti-Taobao alliance" for digital protest actions and in-person protest at Alibaba's headquarters. The Chinese government mediated the dispute, resulting in Taobao revising its seller fees and providing 1.8 billion RMB in support for small businesses using the platform.
In August 2017, the company removed controversial vendors offering personalised messages featuring African children over concerns of child exploitation. Some Chinese Taobao vendors claimed that their promotional videos featuring African children were "charity activity" in which most of the profits goes to the children. However the situation proved more complicated after a photographer contacted by the Beijing Youth Daily said "the children only received snacks or a few dollars as reward", indicating that there was legitimate child exploitation.
In 2019, Taobao removed all items related to the Houston Rockets in response to the organization's general manager Daryl Morey posting a tweet about Hong Kong.
In October 2020 amid rising geopolitical tensions between Taipei and Beijing, Taobao announced that it would exit the Taiwanese market after the Taiwanese government ordered the company to re-register as being backed by China or to leave the island if they don't.
The mobile app of Taobao was banned in India (along with other Chinese apps) on 2 September 2020 by the government, the move came amid the 2020 China-India skirmish.
In 2022, the Office of the United States Trade Representative named Taobao on its list of Notorious Markets for Counterfeiting and Piracy.
Metrics
Taobao Marketplace had more than 5 million registered users as of June 2013 and hosted more than 80 million product listings. It facilitated approximately RMB 200 billion in gross merchandise volume in 2009. In September 2013, Taobao ranked 12th overall in Alexa's internet rankings.
With over 1 billion product listings as of 2016, the combined transaction volume of Taobao Marketplace and Tmall.com reached 3 trillion yuan in 2017.
As of 2020, Taobao hosted ten million online stores, 726 million active buyers, and a gross merchandise value of $945 billion.
As of 2021, Taobao was the 8th most visited website in the world and the 5th most visited website in China.
As of at least 2024, it was the world's most popular online shopping platform as measured by gross merchandise value.
Taobao villages
Taobao villages are rural Chinese villages where the local economy has developed to focus extensively on Taobao. Alibaba's research division defines Taobao villages as those in which (1) businesses are located in an administrative village in a rural area, (2) the village's annual e-commerce revenues exceed RMB 10 million, and (3) the village has either an excess of 100 active online shops or active online shops account for more than 10% of village households.
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Technology
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E-commerce
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10686210
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https://en.wikipedia.org/wiki/Jupiter%20mass
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Jupiter mass
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The Jupiter mass, also called Jovian mass, is the unit of mass equal to the total mass of the planet Jupiter. This value may refer to the mass of the planet alone, or the mass of the entire Jovian system to include the moons of Jupiter. Jupiter is by far the most massive planet in the Solar System. It is approximately 2.5 times as massive as all of the other planets in the Solar System combined.
Jupiter mass is a common unit of mass in astronomy that is used to indicate the masses of other similarly-sized objects, including the outer planets, extrasolar planets, and brown dwarfs, as this unit provides a convenient scale for comparison.
Current best estimates
The current best known value for the mass of Jupiter can be expressed as :
which is about as massive as the Sun (is about ):
Jupiter is 318 times as massive as Earth:
Context and implications
Jupiter's mass is 2.5 times that of all the other planets in the Solar System combined—this is so massive that its barycenter with the Sun lies beyond the Sun's surface at 1.068 solar radii from the Sun's center.
Because the mass of Jupiter is so large compared to the other objects in the Solar System, the effects of its gravity must be included when calculating satellite trajectories and the precise orbits of other bodies in the Solar System, including the Moon and even Pluto.
Theoretical models indicate that if Jupiter had much more mass than it does at present, its atmosphere would collapse, and the planet would shrink. For small changes in mass, the radius would not change appreciably, but above about (1.6 Jupiter masses) the interior would become so much more compressed under the increased pressure that its volume would decrease despite the increasing amount of matter. As a result, Jupiter is thought to have about as large a diameter as a planet of its composition and evolutionary history can achieve. The process of further shrinkage with increasing mass would continue until appreciable stellar ignition was achieved, as in high-mass brown dwarfs having around 50 Jupiter masses. Jupiter would need to be about 80 times as massive to fuse hydrogen and become a star.
Gravitational constant
The mass of Jupiter is derived from the measured value called the Jovian mass parameter, which is denoted with GMJ. The mass of Jupiter is calculated by dividing GMJ by the constant G. For celestial bodies such as Jupiter, Earth and the Sun, the value of the GM product is known to many orders of magnitude more precisely than either factor independently. The limited precision available for G limits the uncertainty of the derived mass. For this reason, astronomers often prefer to refer to the gravitational parameter, rather than the explicit mass. The GM products are used when computing the ratio of Jupiter mass relative to other objects.
In 2015, the International Astronomical Union defined the nominal Jovian mass parameter to remain constant regardless of subsequent improvements in measurement precision of . This constant is defined as exactly
If the explicit mass of Jupiter is needed in SI units, it can be calculated by dividing GM by G, where G is the gravitational constant.
Mass composition
The majority of Jupiter's mass is hydrogen and helium. These two elements make up more than 87% of the total mass of Jupiter. The total mass of heavy elements other than hydrogen and helium in the planet is between 11 and . The bulk of the hydrogen on Jupiter is solid hydrogen. Evidence suggests that Jupiter contains a central dense core. If so, the mass of the core is predicted to be no larger than about . The exact mass of the core is uncertain due to the relatively poor knowledge of the behavior of solid hydrogen at very high pressures.
Relative mass
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Physical sciences
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Mass and weight
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Basics and measurement
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