IPCC Climate Change 2021: The Physical Science Basis

This report was published by the Intergovernmental Panel on Climate Change (IPCC) and documents the findings from Working Group I (the physical science basis). The publication of the findings from Working Group II (impacts, adaptation and vulnerability) and Working Group III (mitigation) will follow next year. 

The report begins with, “it is unequivocal that human influence has warmed the atmosphere, ocean and land” and goes on to describe how human activities are causing the climate change that creates insecurity across the world.

The report documents the increase in greenhouse gas emissions, heatwaves, and heavy rains induced flooding, as well as droughts, hurricanes and typhoons. If greenhouse gas emissions to do not fall significantly over the next couple of decades, 3°C of heating looks likely. If they do not fall at all, then 4-5°C is probable, which would be devastating in terms of life on Earth for both human and non-human species.

The report synthesises five years of scientific assessment, write-up and review. It has been authored, approved and endorsed by 234 leading climate scientists from more than 60 countries. Over 14,000 peer-reviewed climate change research papers have been considered, evaluated and cited within the report. 

There is also a Synthesis Report Outline that you can read here (full report to follow next year). The Synthesis Report will integrate the three Working Group reports with the findings from the three cross-Working Group Special Reports that were produced during the assessment cycle: Special Report on Global Warming (SR15, October 2018), Special Report on Climate Change and Land (SRCCL, August 2019) and Special Report on the Ocean and Cryosphere in a Changing Climate (SROCC, September 2019). 

Click here for a factsheet on the Intergovernmental Panel on Climate Change (IPCC). 

Read the full Climate Change 2021: The Physical Science Basis report here.