AR6 Climate Change 2021: The Physical Science Basis – “The Working Group I contribution to the Sixth Assessment Report addresses the most up-to-date physical understanding of the climate system and climate change, bringing together the latest advances in climate science, and combining multiple lines of evidence from paleoclimate, observations, process understanding, and global and regional climate simulations.”

• Full Report – 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. (1300 pages).”
• Two page executive summary

The New York Times – A Hotter Future Is Certain, Climate Panel Warns. But How Hot Is Up to Us – “Nations have delayed curbing emissions for so long that global warming will inevitably intensify over the next 30 years, a major U.N. report found. There is a short window to avoid the most harrowing future, the report said. Doing so would require a coordinated international effort starting immediately.”

Washington Post – U.N. report warns of grim climate future  unless humans act swiftly – “The report details how humans have altered the environment at an “unprecedented” pace and cautions that the world risks increasingly catastrophic effects in the absence of rapid greenhouse gas reductions..”