Climate Change: Why Are Some Climate Models Running Red Hot? Scientists Have an Answer

tech.hindustantimes.com:

Something funny happened when, three years ago, climate scientists began reporting results from their latest generation of Earth models. A concerning number of them showed accelerated heating. 

These “hot models” quickly raised alarm. It’s a puzzle that’s now well on its way to being solved, according to a commentary published today in the journal Nature by five leading scientists. Advances that include better understanding of the physics of clouds had the unanticipated effect of raising overall temperatures faster in some models. 

With the effects of climate change visible virtually every week, governments, companies, investors and communities are all hungry for high-quality information about what’s coming next. How to treat the hot models is a key part of that, and the authors highlight just how to tap what’s useful about them. 

Climate models are the complex research workhorses that for decades have correctly, for the most part, projected how temperatures would rise from continued greenhouse gas pollution—“the best window on the future world that climate scientists have,” said Richard Betts, head of climate impacts research at the U.K. Met Office, who was not involved in the new article. They are driven by the physics of how carbon dioxide and other gases absorb heat, how much light ice caps reflect to space and myriad other phenomena that generations of scientists have observed in the real world. 

Where physics can’t fully capture natural processes, modelers approximate how the world behaves—and that’s where the headache in the latest model updates probably came about. These models, which formed the backbone of the latest United Nations climate assessment that began publishing in August, included more sophisticated looks