Den opvarmning som er tydelig i måleserierne for temperatur, er forenelig med et bredt spektrum af observationer, som også er dokumenteret af mange uafhængige forskningsgrupper.<ref name="kennedy evidence for global warming">{{Cite journal | author=Kennedy, J.J. | år=2010 | title=How do we know the world has warmed? in: 2. Global Climate, in: State of the Climate in 2009 | url=http://www.ncdc.noaa.gov/bams-state-of-the-climate/2009.php | journal=Bull. Amer. Meteor. Soc. | volume=91 | issue=7 | page=26 | display-authors=etal | access-date= 1. juni 2020 | archive-date=20. august 2015 | archive-url=https://web.archive.org/web/20150820035443/http://www.ncdc.noaa.gov/bams-state-of-the-climate/2009.php |url-status=live }}</ref> Eksempler er [[havniveaustigning]],<ref>{{Cite journal | author=Lindsey, R. | date=10. juli 2012 | titel=ClimateWatch Magazine >> State of the Climate: 2011 Global Sea Level | url=https://www.climate.gov/news-features/understanding-climate/state-climate-2011-global-sea-level | publisher=NOAA Climate Services Portal | access-date=13. april 2020 | archive-date=22. februar 2020 | archive-url=https://web.archive.org/web/20200222203220/https://www.climate.gov/news-features/understanding-climate/state-climate-2011-global-sea-level |url-status=live }}</ref> omfattende smeltning af sne og is på land,<ref>{{Cite book | url=https://archive.ipcc.ch/publications_and_data/ar4/wg1/en/spmsspm-direct-observations.html | title=Direct Observations of Recent Climate Change | chapter=Summary for Policymakers | chapter-url=http://www.ipcc.ch/publications_and_data/ar4/wg1/en/spm.html | access-date= 1. juni 2020 | archive-date=23. juli 2020 | archive-url=https://web.archive.org/web/20200723095206/https://archive.ipcc.ch/publications_and_data/ar4/wg1/en/spmsspm-direct-observations.html |url-status=live }}, in {{harvnb|IPCC AR4 WG1|2007}}</ref> øget varmeindhold i havene,<ref name="kennedy evidence for global warming"/> øget [[luftfugtighed]],<ref name="kennedy evidence for global warming"/> og tidligere [[forår]],<ref>{{Cite book| url=https://archive.ipcc.ch/publications_and_data/ar4/wg2/en/spmsspm-b.html| titel=B. Current knowledge about observed impacts of climate change on the natural and human environment| chapter=Summary for Policymakers| access-date= 1. juni 2020| archive-date=19. december 2019| archive-url=https://web.archive.org/web/20191219023807/https://archive.ipcc.ch/publications_and_data/ar4/wg2/en/spmsspm-b.html|url-status=live}}, in {{harvnb|IPCC AR4 WG2|2007}}</ref> som ses ved [[blomstring]] tidligere på året.<ref>{{Cite book | url=https://archive.ipcc.ch/publications_and_data/ar4/wg2/en/ch1s1-3-5-1.html | title=Sec 1.3.5.1 Changes in phenology | author=Rosenzweig, C. | chapter=Ch 1: Assessment of Observed Changes and Responses in Natural and Managed Systems | display-authors=etal | access-date= 1. juni 2020 | archive-date=19. december 2019 | archive-url=https://web.archive.org/web/20191219031106/https://archive.ipcc.ch/publications_and_data/ar4/wg2/en/ch1s1-3-5-1.html |url-status=live }}, in {{harvnb|IPCC AR4 WG2|2007|p=99}}</ref> [[Sandsynlighed]]en for, at disse ændringer kunne have forekommet ved en tilfældighed er nærmest lig nul.<ref name="kennedy evidence for global warming"/>
Jura Politik Samfund Traktater Miljø_og_samfund Folkeret