The basic facts about climate change have been clear for many decades: Burning fossil fuels produces carbon dioxide, which alters the chemical composition of the atmosphere and causes it to trap ever greater amounts of heat from the sun. Those facts are set in stone. It’s a shame then that, partly because of ugly disinformation campaigns run by fossil fuel companies, we’ve spent the past 30 years debating indisputable facts. We could have saved a lot of time if we had instead butted heads about the things that are still genuinely uncertain.
Consider, for example, the use of computer-generated scenarios to understand our climate future. While mathematical simulation of reality is never perfect—whether you’re predicting the planet’s changing temperature or what song will become your favorite—it is a powerful tool to answer a difficult question: What’s likely to happen next?
Then something happened—something good. As the global climate-science and energy-transformation conversations each grew in scale, the two discovered they weren’t always dealing with the same givens. The energy modelers took one look at RCP 8.5 and how heavily climate scientists relied on it and started clearing their throats—initially on Twitter, and eventually in some of the field’s most prominent journals for research and commentary.
Zeke Hausfather, director of climate and energy at the Breakthrough Institute, argued in Nature in January that the energy system is changing faster than we anticipated, such as through rapid cost declines in renewables. So the projected emissions scenarios under RCP 8.5 should no longer be called “business as usual.” It would be better to adopt the more recently developed SSP scenarios (again, don’t ask), which provide more nuance than the RCP scenarios, which have been use for more than a decade.