Abstract:

The IPCC Working Group I contribution to the Sixth Assessment Report (AR6) improves our understandings of the changes in climate system, the causes of the climate change, and the projected future changes and gives us a clearer and more reliable relationship between human activities and climate change, from the following progress. Comprehensive assessments based on multiple lines of evidence point out that climate across the globe is undergoing unprecedented changes; progress in detection and attribution including event attribution studies has expanded the understandings of human influence on the climate system from the atmosphere to the hydrosphere, cryosphere, and biosphere, further strengthening the understandings of human influence on global and regional climate; the content of relevant regional climate change information is richer, and it is more closely related to the impact of climate change in various industries and sensitive regions, providing strong support for better risk assessment and adaptation planning at regional scale; the improvement of climate models and constraint for projection and the deepened understandings of climate sensitivity have reduced the uncertainty of the projected changes in global surface temperature, ocean warming and sea level under different emission scenarios. This latest report shows great significance in providing guidance for China to improve the level of climate change research and the capability of disaster prevention and mitigation.

Key words: Climate change, New understandings, Attribution, Constrained projection