In 1982, a secret report by scientists at the oil company Exxon predicted with surprising accuracy how quickly the planet’s temperature would rise in coming decades if carbon dioxide emissions associated with fossil fuels continued. In the graph they created you can see that in 2024 they predicted the 420 parts per million (ppm) of CO2 that our atmosphere already contains and the 1°C increase we have already experienced compared to to 1960. Their scientists simply understood.
An analysis carried out by a team of researchers from Harvard University in 2023, and published in the journal Scienceshowed that since the 1970s, the company had correctly calculated the amount of carbon that could be emitted into the atmosphere to contain further global warming below 2°C, “at the same time as orchestrating a campaign propaganda to delay climate action. .”
“We found that their forecasts were not only extremely accurate, but they were also often more accurate than forecasts made by independent academics and government scientists at exactly the same time,” says Naomi Oreskes, co-author of the paper. work.
Everyone predicted it
Why were the predictions of scientists working for a polluting company so accurate? The truth is that climatologists have been very successful in their predictions about global warming. This is confirmed by a NASA study in 2020 and a recent report » from the independent research platform Carbon Brief, which concludes that climate models published since 1973 have been “fairly accurate in projecting future warming”.
We found that Exxon’s forecasts were often more accurate than those made by independent academics and government scientists.
Naomi Oreskes
— Researcher at Harvard University
“Until now, global warming has experienced a linear increase in relation to the increase in CO2 concentration,” adds José Manuel Gutiérrez, director of the Cantabria Institute of Physics (IFCA) and member of the IPCC. “The models simulated this relationship well and, therefore, global warming projections are quite accurate when based on growth trajectories similar to those observed. »
“When it comes to temperature, the projections made by climatologists are very precise,” explains Isabel Moreno, meteorologist and co-host of the show. Here the Earth (TVE). He said the fact that Exxon scientists have identified what has happened over the years is also indicative of the ability we had 50 years ago to know what might happen. “And it should also reassure us about what we say may happen in the future,” he defends.
Exxon’s “crystal ball”
Regarding the Exxon scientists, Gutiérrez does not believe that they were visionaries, but rather that they only corroborated what science already said. “Their estimates are very good, similar to those made by the CMIP experiments, the global simulations used by the IPCC,” recognizes Francisco Doblas, ICREA professor and climatologist at the Barcelona Supercomputing Center (BSC-CNS) who also participated in the study. IPCC.
The difference between Exxon’s temperature forecasts and the projections that scientists began making then and are making today is the level of complexity. “Our models attempt to estimate the impact of this temperature increase on other climate parameters, such as precipitation, at a regional level and not so much at a global level. This is where the assessment is complicated,” explains Gutiérrez. “The models allow us to analyze more complex scenarios, such as emissions trajectories, with more or less mitigation efforts and project the consequences at the regional level.”
On the other hand, underlines the expert, the validation of these curves can only be carried out if they are accompanied by estimates of their uncertainty, which Exxon’s models did not include and therefore could not be compared. “What we can say is that both are going in the same direction: the expected increase in CO2 has led to an increase in temperature quite similar to the observations,” he says.
A winning bet
“Exxon provided reliable estimates of temperature increase because it took into account the physics behind climate change due to human activity and used an appropriate assumption for emissions growth,” says Doblas. This reveals a somewhat obvious, but no less telling, reality: Exxon scientists were right in predicting that CO2 emissions would continue to rise, as they have, despite decades of corporate efforts. from those fighting against climate change.
Exxon provided reliable estimates because it took into account the physics behind climate change due to human activity and used an appropriate assumption for emissions growth.
Francisco Doblas
— ICREA Professor and climatologist at the Barcelona Supercomputing Center (BSC-CNS).
“I imagine that the Exxon specialists had a very good idea of where the greenhouse gas emissions were going,” says Doblas. “Once you know that, a simple energy balance model gives you a fairly reliable estimate of the corresponding increase in global average temperature.”
As they pointed out Geoffrey Supran And Naomi Oreskes in his 2023 article in Sciencewhat happened was that Exxon scientists ruled out the possibility that there was no anthropogenic global warming. “At no time did the company’s scientists suggest that human-caused global warming would not occur,” they wrote. And its success came from the assumption that we were not going to stop filling the atmosphere with greenhouse gases.
They had correct information, but they invested in publishing lies instead of publishing the truth they knew perfectly well.
Jose Manuel Gutiérrez
— Director of the Cantabria Institute of Physics (IFCA) and member of the IPCC
“I would say that Exxon was fully informed and aligned with the science of climate change and they knew (like the rest of the scientists) what was happening and how it was going to evolve,” says Gutiérrez. “They had the correct information, but they invested in publishing lies instead of publishing the truth that they knew perfectly well. ” Perhaps at that time it did not seem to them that an increase of one degree, or even two, justified a change in economic model – he speculates – and they did not see anything catastrophic in it. horizon, facing the dangers of a cold. war scenario, so they decided to keep shooting.
New maximum emissions
On the occasion of the start of the Baku Climate Conference (COP29), the annual Global Carbon Budget report has just been published, which indicates that, far from being reduced, global CO2 emissions have reached a new maximum , so the upward trend line mapped by Exxon scientists will continue to be accurate.
“Ultimately, this situation is proof that everything that was done after the fact to deny climate change was based on other interests and not on science,” says Isabel Moreno. And Exxon was right because they opted for a scenario that suited the company very well: that emissions from fossil fuel consumption would continue to increase at the same rate in the future and that we would do nothing about it. avoid, which is what ultimately happened. With the aggravating circumstance that “they contributed to the disinformation to make this happen,” concludes Gutiérrez.
