Summary
Next month the U.N. Intergovernmental Panel on Climate Change will begin to release its first major assessment of human-caused global warming since 2013. The report will drop on a world that has starkly changed in 8 years, warming by more than 0.3┬░C to nearly 1.3┬░C above preindustrial levels. Weather has grown more severe, seas are measurably higher, and mountain glaciers and polar ice have shrunk sharply. But the report’s authors face a challenge that many of the world’s leading climate models, used for the report’s projections, are now showing warming rates that most scientists believe are implausibly fast because of errors in rendering clouds. Scientists have scrambled to adapt to this new reality, constraining model projections with recent warming and adopting new techniques to convey the impacts of climate change.