Evaluation of claimed “leveling off” of warming in satellite temperature data. Results are for monthly-mean anomalies in the temperature of the mid- to upper troposphere (TMT), corrected for stratospheric cooling8 and spatially averaged over 82.5°N–82.5°S. The average of the latest satellite dataset versions (RSS v4.0, STAR v4.0, and UAH v6.0) has a warming trend of 0.181 °C/decade over the 456-month period from January 1979 to December 2016 (panel A). Graphic: Santer, et al., 2017 / Nature Scientific Reports

By Chris Mooney
24 May 2017
(The Washington Post) – In a sign of growing tensions between scientists and the Trump administration, researchers published a scientific paper Wednesday that was conceived and written as an explicit refutation to an assertion by Environmental Protection Agency Administrator Scott Pruitt about climate change.The study, in the journal Nature Scientific Reports, sets up a direct test of a claim by Pruitt, made in written Senate comments following his confirmation hearing, that “over the past two decades satellite data indicates there has been a leveling off of warming.”After reviewing temperature trends contained in three satellite data sets going back to 1979, the paper concludes that the data sets show a global warming trend — and that Pruitt was incorrect.“Satellite temperature measurements do not support the claim of a ‘leveling off of warming’ over the past two decades,” write the authors, led by Benjamin Santer of Lawrence Livermore National Laboratory. Santer co-authored the study with three Livermore colleagues and scientists from MIT, the University of Washington in Seattle and Remote Sensing Systems, which keeps one of the three satellite temperature data sets.“In my opinion, when incorrect science is elevated to the level of formal congressional testimony and makes its way into the official congressional record, climate scientists have some responsibility to test specific claims that were made, determine whether those claims are correct or not, and publish their results,” said Santer in an interview, when asked about the framing of the research. [more]

Scientists just published an entire study refuting Scott Pruitt on climate change

ABSTRACT: Satellite temperature measurements do not support the recent claim of a “leveling off of warming” over the past two decades. Tropospheric warming trends over recent 20-year periods are always significantly larger (at the 10% level or better) than model estimates of 20-year trends arising from natural internal variability. Over the full 38-year period of the satellite record, the separation between observed warming and internal variability estimates is even clearer. In two out of three recent satellite datasets, the tropospheric warming from 1979 to 2016 is unprecedented relative to internally generated temperature trends on the 38-year timescale.

Tropospheric Warming Over The Past Two Decades