Don’t believe the hype about the ‘molecule that could solve climate change’
Some chemists came up with a really clever way to observe the intermediate stage of an atmospheric chemical reaction, and then some PR flack got a hold of it and suddenly science has invented a brand-new molecule that will solve all our climate change woes! As usual, things that seem too good to be true probably are.
The supposed miracle molecules, Criegee biradicals, are a short-lived intermediate step in the reaction of ozone (the major component of smog) with alkenes (organic molecules produced by plants and a few industrial sources). Scientists used bursts of light 100 times more powerful than the sun to detect the Criegee biradicals, confirming for the first time that these formerly-theoretical intermediates actually exist.
What’s interesting about them is that Criegee biradicals react with pollutants in the atmosphere to form aerosols, which is a generic term for tiny particles in the atmosphere that (generally) reflect sunlight back into space. Here’s how one of the researchers put it in an interview with LiveScience, which is apparently the only news outlet that bothered to call up the authors of the paper instead of just regurgitating the press release:
Given that 90 percent of the alkenes in the atmosphere that produce these intermediates come from Earth’s ecosystems, the results suggest that “the ecosystem is negating climate change more efficiently than we thought it was,” said study co-author Carl Percival, an atmospheric chemist at the University of Manchester in the United Kingdom. “The most important message here is that we need to protect the ecosystems we have left.”
So! It turns out plants are shielding the planet from even more global warming by a previously not-so-well-understood mechanism. And that if we kill the plants, it’s another way we’ll accelerate climate change. But making the leap from that conclusion to some kind of hypothetical, never-outlined geoengineering scheme is more than a little premature.
Percival noted that scientists aren’t close to being ready to use the intermediates in geoengineering to generate more aerosols and proactively cool Earth’s climate. The main point, he said, is that we need to preserve the ecosystem so that it can naturally produce more Criegee intermediates.
How mysterious molecules may help cool earth,