Droughts, rising temperatures, and extreme weather negatively impact agriculture. ", IPCC AR5 SYR Summary for Policymakers 2014, "What are the inputs and outputs for a climate model? Climate Focus Client Brief on the Paris Agreement III", Warming projections global update, December 2019, "The climate regime from The Hague to Marrakech: Saving or sinking the Kyoto Protocol? The study said that if the world built all of the coal plants that were currently planned, carbon dioxide levels would rise so much that the world would not be able to keep the temperature increase below this limit [1]. The percentage declines likely in 2020, however, would need to be repeated, year after year, to reach net-zero Nutzen Sie zeit.de mit weniger Werbung und ohne Werbetracking für 1,20 €/Woche (für Digital-Abonnenten nur 0,40 €/Woche). On the timescale of centuries to millennia, the magnitude of climate change will be determined primarily by anthropogenic CO2 emissions.

The future balance of these opposing effects is unclear. [184], Climate change has likely already increased global economic inequality, and is projected to continue doing so. [187] Current inequalities between men and women, between rich and poor, and between different ethnicities have been observed to worsen as a consequence of climate variability and climate change. [1] Though there have been previous periods of climatic change, since the mid-20th century the rate of human impact on Earth's climate system and the global scale of that impact have been unprecedented.[2]. [295] Public reactions to climate change and concern about its effects have been increasing, with many perceiving it as the worst global threat.

", "Climate change could render many of Earth's ecosystems unrecognizable", "WHO calls for urgent action to protect health from climate change – Sign the call", "How Effective Is Land At Removing Carbon Pollution? Ecological collapse possibilities. Some people have suggested trying to keep Earth’s temperature increase below 2 °C (3.6 °F).

[36], Global warming refers to global averages, with the amount of warming varying by region. Drought and high temperatures worsened the 2020 bushfires in Australia.

[117] Sea level rise since 1990 was underestimated in older models, but now agrees well with observations. In this respect they act as suppressing feedbacks in global warming. [285] Scientific discussion takes place in journal articles that are peer-reviewed, which scientists subject to assessment every couple of years in the Intergovernmental Panel on Climate Change reports. [323] Global warming became the most popular term after NASA climate scientist James Hansen used it in his 1988 testimony in the U.S.

[162] Ocean acidification threatens damage to coral reefs, fisheries, protected species, and other natural resources of value to society. Mild winters allow more pine beetles to survive to kill large swaths of forest.
[280], While ozone depletion and global warming are considered separate problems, the solution to the former has significantly mitigated global warming. overwhelming scientific consensus that global surface temperatures have increased, IPCC AR5 WG1 Summary for Policymakers 2013, "Scientific Consensus: Earth's Climate is Warming", United Nations Environment Programme 2019, "Global Annual Mean Surface Air Temperature Change", United States Environmental Protection Agency 2016, Union of Concerned Scientists, 9 December 2012, The Sustainability Consortium, 13 September 2018, World Resources Institute, 8 December 2019, "AGU Centennial Grand Challenge: Volcanoes and Deep Carbon Global CO 2 Emissions From Subaerial Volcanism—Recent Progress and Future Challenges", "The study of Earth as an integrated system", "Controls of the transient climate response to emissions by physical feedbacks, heat uptake and carbon cycling", "What are the different types of climate models? ", "What is the United Nations Framework Convention on Climate Change?


Experts thought climate would be self-regulating. Many arctic animals rely on sea ice, which has been disappearing in a warming Arctic.

", "2019 was the year of 'climate emergency' declarations", "Getting to 100% renewables requires cheap energy storage. [256] The geopolitics are further complicated by the supply chain of rare earth metals necessary to produce many clean technologies. [275] The long version of Target 13.a is: "Implement the commitment undertaken by developed-country parties to the United Nations Framework Convention on Climate Change to a goal of mobilizing jointly $100 billion annually by 2020 from all sources to address the needs of developing countries in the context of meaningful mitigation actions and transparency on implementation and fully operationalize the Green Climate Fund through its capitalization as soon as possible. [208] Photovoltaic solar and wind, in particular, have seen substantial growth and progress over the last few years, such that they are currently among the cheapest sources of new power generation.

Mr. Habercorn, "the things are going faster" because it is the roll out of a huge industry. [277] Other countries and jurisdictions followed suit.

[45], By itself, the climate system experiences various cycles which can last for years (such as the El Niño–Southern Oscillation) to decades or centuries. [155], Recent warming has driven many terrestrial and freshwater species poleward and towards higher altitudes.