Climate Change 2021: The Physical Science Basis

Climate change is widespread, rapid and intensifying. That is the key finding of the latest scientific report from the Intergovernmental Panel on Climate Change. It finds changes in the Earth’s climate in every region and across the whole climate system. Many changes are unprecedented in thousands, if not hundreds of thousands of years. Some, such as continued sea-level rise, are irreversible over hundreds to thousands of years. The report points to strong and sustained reductions in emissions of carbon dioxide and other greenhouse gases to limit climate change. Benefits for air quality would come quickly, while global temperatures would take 20-30 years to stabilize. The report, issued by the IPCC’s Working Group I and approved by 195 member governments, is the first in a series leading up to the 2022 IPCC Sixth Assessment Report. It includes a closer look at the regional dimensions of climate change and builds on advances in attributing specific weather and climate events to climate change.