The thirteen chapters of the Working Group I report provide an assessment of the current evidence on the physical science of climate change, knowledge evaluation gained from observations, reanalyses, paleoclimate archives and climate model simulations, as well as physical, chemical and biological climate processes.

- Full report:
https://www.ipcc.ch/report/ar6/wg1/downloads/report/IPCC_AR6_WGI_Full_Report.pdf

- AR6 Climate Change 2021: The Physical Science Basis
https://www.ipcc.ch/report/ar6/wg1/