linguistic:translation, structural:scholar_edition
Climate change

South Asian countries are expected to experience more flooding in the future as the monsoon pattern intensifies. Across Asia as a whole, 100-year extremes in vapor transport (directly related to extreme precipitation) would become 2.6 times more frequent under 1.5 °C (2.7 °F) of global warming, yet 3.9 and 7.5 times more frequent under 2 °C (3.6 °F) and 3 °C (5.4 °F). In parts of South Asia, they could become up to 15 times more frequent. At the same time, up to two-thirds of glacier ice in the Hindu Kush region may melt by 2100 under high warming, and these glaciers feed the water basin of over 220 million people. As glacier meltwater flow diminishes after 2050, Hydropower generation would become less predictable and reliable, while agriculture would become more reliant on the intensified monsoon than ever before. Around 2050, people living in the Ganges and Indus river basins (where up to 60% of non-monsoon irrigation comes from the glaciers) may be faced with severe water scarcity due to both climate and socioeconomic reasons.

By 2030, major Indian cities such as Mumbai, Kolkata, Cuttack and Kochi are expected to end up with much of their territory below the tide level. In Mumbai alone, failing to adapt to this would result in damages of US$112–162 billion by 2050, which would nearly triple by 2070. Sea level rise in Bangladesh will displace 0.9–2.1 million people by 2050 and may force the relocation of up to one third of power plants by 2030. Food security will become more uneven, and some South Asian countries could experience significant social impacts from global food price volatility. Infectious diarrhoea mortality and dengue fever incidence is also likely to increase across South Asia. Parts of South Asia would also reach "critical health thresholds" for heat stress under all but the lowest-emission climate change scenarios. Under the high-emission scenario, 40 million people (nearly 2% of the South Asian population) may be driven to internal migration by 2050 due to climate change.

India is estimated to have the world's highest social cost of carbon - meaning that it experiences the greatest impact from greenhouse gas emissions. Other estimates describe Bangladesh as the country most likely to be the worst-affected. In the 2017 edition of Germanwatch 's Climate Risk Index, Bangladesh and Pakistan ranked sixth and seventh respectively as the countries most affected by climate change in the period from 1996 to 2015, while India ranked fourth among the list of countries most affected by climate change in 2015. Some research suggests that South Asia as a whole would lose 2% of its GDP to climate change by 2050, while these losses would approach 9% by the end of the century under the most intense climate change scenario.