Change in global ocean heat content (∆OHC). a, ∆OHC derived from hydrographic and atmospheric observations (normalized to zero in 2007, ±1σ uncertainty). b, Linear least-squares trends for 1991–2016, 1993–2016 and 2007–2016 (±1σ uncertainty). Hydrography-based ∆OHC estimates combine warming rates at ocean depths of 0 to 2,000m (from Cheng and co-authors (CHEN), Pacific Marine Environmental Laboratory (PMEL), Meteorological Research Institute (MRI), and National Centers for Environmental Information (NCEI) estimates) with the revised deep ocean warming (at depths of more than 2,000 m). The atmospheric-based estimate (this study), which uses observed atmospheric potential oxygen trends (∆APO Climate ) and model-based ∆APO Climate-to-∆OHC ratios, does not resolve interannual variations. Graphic: Resplandy, et al., 2018 / Nature

By Chris Mooney and Brady Dennis
13 November 2018
(The Washington Post) – Scientists behind a major study that claimed the Earth’s oceans are warming faster than previously thought now say their work contained inadvertent errors that made their conclusions seem more certain than they actually are. [cf. Earth’s oceans have absorbed 60 percent more heat per year than previously thought]
Two weeks after the high-profile study was published in the journal Nature, its authors have submitted corrections to the publication. The Scripps Institution of Oceanography, home to several of the researchers involved, also noted the problems in the scientists’ work and corrected a news release on its website, which previously had asserted that the study detailed how the Earth’s oceans “have absorbed 60 percent more heat than previously thought.”
“Unfortunately, we made mistakes here,” said Ralph Keeling, a climate scientist at Scripps, who was a co-author of the study. “I think the main lesson is that you work as fast as you can to fix mistakes when you find them.”The central problem, according to Keeling, came in how the researchers dealt with the uncertainty in their measurements. As a result, the findings suffer from too much doubt to definitively support the paper’s conclusion about how much heat the oceans have absorbed over time.The central conclusion of the study — that oceans are retaining ever more energy as more heat is being trapped within Earth’s climate system each year — is in line with other studies that have drawn similar conclusions. And it hasn’t changed much despite the errors. But Keeling said the authors’ miscalculations mean there is a much larger margin of error in the findings, which means researchers can weigh in with less certainty than they thought.“I accept responsibility for what happened because it’s my role to make sure that those kind of details got conveyed,” Keeling said. (He has published a more detailed explanation of what happened here.) […]Gavin Schmidt, head of the NASA Goddard Institute for Space Studies, followed the growing debate over the study closely on Twitter and said that measurements about the uptake of heat in the oceans have been bedeviled with data problems for some time — and that debuting new research in this area is hard. […]“The key is not whether mistakes are made, but how they are dealt with — and the response from Laure and Ralph here is exemplary. No panic, but a careful reexamination of their working — despite a somewhat hostile environment,” he wrote. [more]

Scientists acknowledge key errors in study of how fast the oceans are warming