“Domino-effect of climate events could move Earth into a ‘hothouse’ state” is how the Guardian described the findings of a study published this week Proceedings of the National Academy of Sciences. The BBC went with “Climate change: ‘Hothouse Earth’ risks even if CO2 emissions slashed”
If you’ve followed the story of the changing environment at all in recent years, you’re likely not surprised by these headlines. The risks of climate change have been clear to us since at least the 1980s, and the predictions of environmental destruction to hit Earth have mostly gotten worse.
That said, there’s still a sizeable population on the planet that doesn’t care about climate change or, worse, denies it’s real. To turn those people around, some of the world’s most preeminent scientists have figured out it makes sense to publish global-warming studies when it’s hot outside.
It was the trick Jim Hansen, one of the world’s leading lights on climate change, used when he gave his now-famous testimony to the US Congress on a blistering hot day in June 1988. In a recent story for the New York Times, Nathaniel Rich shared how the testimony was timed:
Hansen told Pomerance that the biggest problem with the Johnston hearing, at least apart from the whole censorship business, had been the month in which it was held: November. “This business of having global-warming hearings in such cool weather is never going to get attention,” he said. He wasn’t joking. At first he assumed that it was enough to publish studies about global warming and that the government would spring into action. Then he figured that his statements to Congress would do it. It had seemed, at least momentarily, that industry, understanding what was at stake, might lead. But nothing had worked.
On June 22 in Washington, where it hit 100 degrees, Rafe Pomerance received a call from Jim Hansen, who was scheduled to testify the following morning at a Senate hearing called by Timothy Wirth. “I hope we have good media coverage tomorrow,” Hansen said.
This amused Pomerance. He was the one who tended to worry about press; Hansen usually claimed indifference to such vulgar considerations. “Why’s that?” Pomerance asked. Hansen had just received the most recent global temperature data. Just over halfway into the year, 1988 was setting records. Already it had nearly clinched the hottest year in history. Ahead of schedule, the signal was emerging from the noise. “I’m going to make a pretty strong statement,” Hansen said.
Science is supposed to present reality as it exists. And, yet, what Hansen understood back then is that context matters as much as logical arguments. Weather is a localized phenomenon to which long-term climate trends contribute. One hot summer doesn’t prove that global warming is here—but it opens people up to having a conversation about the possibility.
Take this 2018 climate-change survey from the University of Michigan. It found that 73% of Americans think there is solid evidence of global warming, and that 60% believe at least some of the blame lies with human activity. Both those were record highs in the 10 years the university has been conducting the survey. It’s likely no coincidence that the 2018 survey was conducted in May, which was hotter than any May in 124 years of record keeping.
“There’s lots of evidence that contemporary weather is a contributing factor to belief in climate change,” Chris Borick, director of the Muhlenberg College Institute of Public Opinion, told the Guardian. “But there are other factors. People are telling us they are experiencing a climate that isn’t what they remember in the past and the evidence itself, such as declining polar ice, is having an effect.”
Many of the predictions made in the decades past about the effects of global warming are coming true today. And without serious reductions in emissions, it’s only going to get worse. The hothouse study talks about feedback loops where, for example, a warmer Arctic causes methane from under the ocean to well up, leading to more warming.
The good news is that it’s not too late. “We as a global community can also manage our relationship with the system to influence future planetary conditions,” Katherine Richardson of the University of Copenhagen told the BBC. But it will require bold moves, such as switching to fully zero-carbon energy sources by mid-century, readying ways to suck carbon dioxide from the air, and maybe even consider solar geoengineering. All that, however, will require all of us to believe that the threat of global warming is real and deserves drastic action.