The climate ‘crisis’ isn’t what it used to be
Judith Curry | Growing realization by the climate establishment that the threat of future warming has been cut in half over the past 5 years. Summary: The climate “catastrophe” isn’t what it used to be. Circa 2013 with publication of the IPCC AR5 Report, RCP8.5 was regarded as the business-as-usual emissions scenario, with expected warming of 4 to 5 oC by 2100. Now there is growing acceptance that RCP8.5 is implausible, and RCP4.5 is arguably the current business-as-usual emissions scenario. Only a few years ago, an emissions trajectory that followed RCP4.5 with 2 to 3 oC warming was regarded as climate policy success. As limiting warming to 2 oC seems to be in reach (now deemed to be the “threshold of catastrophe”),[i] the goal posts were moved in 2018 to reduce the warming target to 1.5 oC. Climate catastrophe rhetoric now seems linked to extreme weather events, most of which are difficult to identify any role for human-caused climate change in increasing either their intensity or frequency.