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'''This article is about the causes, nature and effects of the warming and resultant climate change that Earth has been experiencing. For other uses, see Global warming (disambiguation).  "Climate change" redirects here. For a broader discussion of climate trends throughout Earth's history, see climate change (general concept). For the album by Pitbull, see Climate Change (album).

Average global temperatures from 2010 to 2019 compared to a baseline average from 1951 to 1978. Source: NASA.

Observed temperature from NASA (black line)[1] vs 1850-1900 average as per IPCC definition of pre-industrial temperature.[2] The primary driver for increased global temperatures in the industrial era is human activity (red line), with natural forces (green line) adding variability.[3]

The primary causes[4] and the wide-ranging effects[5][6]of global warming and resulting climate change. Some effects are feedback mechanisms that intensify climate change and move it toward climate tipping points.[7]

Global warming is the long-term rise in the average temperature of the Earth's climate system. It is a major aspect of climate changeand has been demonstrated by direct temperature measurements and by measurements of various effects of the warming.[8]Global warming and climate change are often used interchangeably.[9] But, more accurately, global warming is the mainly human-caused increase in global surface temperatures and its projected continuation,[10]while climate changeincludes both global warming and its effects, such as changes in precipitation.[11] While there have been prehistoric periods of global warming,[12] observed changes since the mid-20th century have been unprecedented in rate and scale.[13]

The Intergovernmental Panel on Climate Change(IPCC) Fifth Assessment Report concluded, "It is extremely likely that human influence has been the dominant cause of the observed warming since the mid-20th century".[14] The largest human influence has been the emission of greenhouse gases such as carbon dioxide, methane, and nitrous oxide. Fossil fuel burning is the dominant source of these gases, with agricultural emissions and deforestation also playing significant roles.[15] These findings have been recognized by the national science academies of the major industrialized nations[16][17] and are not disputed by any scientific body of national or international standing.[18][19]

The effects of global warming include rising sea levels, regional changes in precipitation, more frequent extreme weather events such as heat waves, and expansion of deserts.[20] Surface temperature increases are greatest in the Arctic, which have contributed to the retreat of glaciers, permafrost, and sea ice. Overall, higher temperatures bring more rain and snowfall, but for some regions droughts and wildfires increase instead.[21] Climate change threatens to diminish crop yields, harming food security, and rising sea levels may flood coastal infrastructure and force the abandonment of many coastal cities.[22] Environmental impacts include the extinction or relocation of many species as their ecosystems change, most immediately in coral reefs, mountains, and the Arctic.[23] Some impacts, such as loss of snow cover, increased water vapour, and melting permafrost, cause feedback effects that further increase the rate of global warming.[24] Ocean acidification caused by increased CO 2 levels is commonly grouped with these effects even though it is not driven by temperature.

Mitigation efforts to address global warming include the development and deployment of low carbon energy technologies, policies to reduce fossil fuel emissions, reforestation, forest preservation, as well as the development of potential climate engineeringtechnologies. Societies and governments are also working to adapt to current and future global warming impacts, including improved coastline protection, better disaster management, and the development of more resistant crops.

Countries work together on climate change under the umbrella of the United Nations Framework Convention on Climate Change (UNFCCC), which entered into force in 1994 and has near-universal membership. The ultimate goal of the convention is to "prevent dangerous anthropogenic interference with the climate system".[25] Although the parties to the UNFCCC have agreed that deep cuts in emissionsare required[26] and that global warming should be limited to well below 2 °C (3.6 °F) in the Paris Agreement of 2016,[27] the Earth's average surface temperature has already increased by about half this threshold.[28] With current policies and pledges, global warming by the end of the century is expected to reach just over 2 °C to 4 °C, depending on how sensitive the climate is to emissions.[29] The IPCC has stressed the need to keep global warming below 1.5 °C compared to pre-industrial levels in order to avoid irreversible impacts.[30] At the current greenhouse gas (GHG) emission rate of 42 gigatons (Gt) per year, the carbon budget for staying below 1.5 °C would be exhausted by 2028.[31