Cambridge, MA — A climate forecast reported by ExxonMobil scientists from 1977 to 2003 was accurate and deft in predicting subsequent global warming and contradicts the company’s public statements, A new Harvard study shows.
In the first systematic review of the fossil fuel industry’s climate projections, researchers at Harvard University and the Potsdam Institute for Climate Impact Research have put a number on what’s ‘Exxon’ know’ decades ago about climate science: that burning fossil fuels would lead to 0.20 ± 0.04 degrees Celsius of global warming per decade.
The findings, published in the peer-reviewed journal Science and summarized by a single graph showing all global warming projections reported by Exxon and ExxonMobil Corp scientists from 1977 to 2003, based on statistical analyzes of unconventional data. previously reported were buried in the company’s own documents.
While it’s widely known that Exxon has known about the threat of global warming since the 1970s, this study is the company’s first quantitative assessment of early climate science. Previous research has focused on Exxon’s internal and externally inconsistent claims about climate change. This report delves into the company’s data revealing that the company knows how much warming will happen with incredible accuracy.
The report concludes: “We found that most of their forecasts correctly predicted warming in line with subsequent observations. “Their predictions are as consistent with, and at least as skillfully, as those predicted by independent academic and government models.”
Using IPCC’s established statistical techniques, the study found that 63-83% of the global warming predictions reported by ExxonMobil scientists were consistent with then observed temperatures. In addition, the predictions modeled by ExxonMobil scientists had an average ‘skill score’ of 72 ± 6%, with a top score of 99%. By comparison, the global warming projections by NASA scientist Dr. James Hansen, presented to the US Congress in 1988, had skill scores ranging from 38% to 66%. (When we take into account the difference between forecast and observed atmospheric CO2 At different levels, the ‘skill score’ of predictions modeled by ExxonMobil scientists was 75 ± 5%, with seven predictions scoring 85% or more. Again, for comparison, the 1988 Hansen predictions have skill scores between 28 and 81%, respectively.)
The study found that “Exxon and ExxonMobil Corp also correctly rejected the prospect of an upcoming ice age, accurately predicting when human-caused global warming was first detected and estimated. reasonable ‘carbon budget’ to keep warming below 2°C. On each of these points, however, the company’s public statements about climate science contradict its own scientific data.”
The study adds weight to the ongoing legal and political investigations into ExxonMobil.
These findings corroborate and add quantitative accuracy to assertions by academics, journalists, lawyers, politicians, and others that ExxonMobil accurately predicted, the authors write. threat of human-caused global warming, both before and in tandem with organizing lobbying and propaganda campaigns to delay climate action and refute ExxonMobil Corp’s claims and their defenders that these claims are incorrect.”
“This is the nail in the coffin of ExxonMobil complain that it has been falsely accused of climate instability,” commented lead author and Harvard Research Associate Geoffrey Supran (Supran began as Associate Professor of Environmental Science and Policy at Harvard University). at the University of Miami’s Rosenstiel School of Marine, Atmospheric and Earth Sciences in January 2023). “Our analysis shows that ExxonMobil’s own data contradicts its public statements, including exaggerating uncertainty, criticizing climate models, and mythologizing global cooling. demand and pretend not to know when — or if — human-caused global warming can be measured, while remaining silent on the issue. threat of trapped fossil fuel assets.
The paper’s acclaim states that this study was supported by the Harvard University Faculties Development Fund and the Rockefeller Family Foundation.
