Climate Sensitivity to CO2 Emissions: More Accurate and Higher Level

AGU, July 21, 2020

Earth’s global “climate sensitivity” to CO2 emissions remains a fundamental question in predicting the future climate.  Until now, scientists relied on a 1979 estimate of 1.5‐4.5°C per doubling of atmospheric carbon dioxide (assuming no other climate forcing).  For the first time in 40 years, this consensus report – part of preparation for the next IPCC Assessment Report, AR6 – amends this estimate, placing climate sensitivity near the middle or upper part of this range, between 2.6-4.1°C. The authors conclude that it now appears extremely unlikely that temperatures well in excess of 2°C can be avoided under high emissions scenarios.

Compiled by Amy Imdieke