At a glanceThe 2021 Working Group I report assessed the physical science of climate change. It described widespread changes, human influence and differing outcomes under different emissions pathways.
Which report was released
On August 9, 2021, the IPCC released the Working Group I contribution to its Sixth Assessment Report, titled Climate Change 2021: The Physical Science Basis. It was an assessment of research, observations and models, rather than a single new experiment.
The release described changes across the climate system and said sustained reductions in greenhouse-gas emissions would limit future change. Its remit was the physical science; a report's working group and year help identify which questions it is designed to answer.
Source [1]What the assessment said about extremes
The Summary for Policymakers reported that human influence was already affecting many weather and climate extremes. It assessed increased frequency and intensity of hot extremes across most land regions and changes in heavy precipitation where observations were sufficient, while attaching confidence and likelihood language to its conclusions.
That language is part of the finding. 'High confidence' describes the strength of the assessment, while a probability expression addresses likelihood. Removing the qualifications can make a scientific statement sound either more absolute or less informative than the authors intended.
Source [2]Scenarios are conditional pathways
The report compared outcomes at different warming levels and under different greenhouse-gas-emissions scenarios. A scenario asks how the climate responds under stated assumptions. It should not be read as a claim that all policy choices lead to an identical outcome.
Likewise, a global assessment is not a neighborhood forecast or a warning for a specific storm. NewsCubby's weather page provides local forecasts and official alerts; the climate report supplies a different, longer-term layer of context.
Source [2]