Another group of prominent climate scientists have published research claiming humanity may have a couple extra decades before pushing the world past what the U.N. calls “dangerous” levels of global warming.
However, the importance of the study isn’t in future projections — which always have high amounts of uncertainty — but rather in its endorsement of the new “consensus” on global warming.
The study, published in the journal Nature Geoscience, provides more confirmation the climate models are running too hot and could not predict the 15-year “hiatus” in global warming.
“We haven’t seen that rapid acceleration in warming after 2000 that we see in the models. We haven’t seen that in the observations,” Myles Allen, a geosystem scientist at the University of Oxford, told The Times on Monday.
“The models end up with a warming which is larger than the observed warming for the current emissions. … So, therefore, they derive a budget which is much lower,” study co-author Pierre Friedlingstein of the University of Exeter said, according to The Washington Post.
Most climate models over-predicted the amount of warming during the early 21st Century. From 1998 to 2014, there wasn’t much of an increase in global average surface temperature readings. Satellite data showed a more than 20-year “hiatus” in warming.
However, scientists have debated whether or not the “hiatus” in warming was due to instrumental errors or natural climate variations the models didn’t take into account.
Co-author Joeri Rogelj of the International Institute for Applied Systems Analysis told WaPo the sophisticated climate models used by the Intergovernmental Panel on Climate Change (IPCC) “tend to slightly overestimate historical warming, and at the same time underestimate compatible historical CO2 emissions.”
“These two small discrepancies accumulate over time and lead to an slight underestimation of the remaining carbon budget,” Rogelj told WaPo. “What we did in this study is to reset the uncertainties, starting from where we are today.”
For years, global warming skeptics argued the models were showing more warming than actual observations, and it wasn’t until 2016 that prominent scientists admitted they were right.
Cato Institute scientists Patrick Michaels and Chip Knappenberger have noted the climate models have been over-hyping warming for decades. Scientist John Christy of the University of Alabama-Huntsville has testified before Congress on the matter.
Christy’s research has shown climate models show 2.5 times more warming in the bulk atmosphere than has been observed.
This study is only the latest to confirm the “hiatus” happened. This author and atmospheric scientist Ryan Maue wrote about the new “consensus” on global warming in the wake of a June study by prominent climate scientists.
That study found “satellite-derived tropospheric warming trends were generally smaller than trends estimated from a large multi-model ensemble.”
Still, some scientists have criticized the new study.
Potsdam Institute scientist Stefan Rahmstorf told WaPo the new study “adjusted the budget upward based on the idea that there has been less observed warming than suggested by the climate models, but that is not actually true if you do the comparison properly.”