Have we been accidentally geoengineering for decades?
Science broadcaster extraordinaire Hank Green wrote on X, the platform formerly known as Twitter, on Friday, August 4, 2022, on the subject of a major source of sulfur dioxide in Earth’s atmosphere … international shipping. He said:
Big ships use dirty fuels, dumping a ton of sulfur dioxide into the atmosphere, thus seeding clouds. You can actually see them from space …they’re called ship tracks.
Why should we care? Because, as Green explains in the video above, sulfur dioxide molecules in the air can cause cooling (yes, cooling) in the atmosphere over a specific area. The cloud seeding is what causes it. He also was careful to mention that the cooling effect doesn’t last very long, nowhere near as long as the effect of global warming by carbon dioxide.
But, here’s the thing. In 2020, the U.N.’s International Maritime Organization ordered the world of international shipping to clean up its fuels. And so they have. Ships have burned cleaner fuels as they’ve crossed Earth’s oceans over the past several years.
Could we, should we … will we?
Now, Hank Green believes, there’s evidence that the semi-unintentional pumping of sulfur dioxide into Earth’s atmosphere was indeed causing cooling. It has now ended due to the new requirement for shipping to clean up its fuels.
He also seems to think, as many are beginning to think (even me, and I hate this idea) that some form of geoengineering – some form of the intentional changing of Earth’s atmosphere, in order to cool Earth or at least keep it from warming further – is going to become necessary in the years and decades ahead.
So will sulfur dioxide be used in the decades ahead to promote global cooling? For the full story, check out Hank’s video above, and/or his … what do we call these things now? Xs? at the bottom of this post.
Accidentally geoengineering
To see Hank Green’s clear explanation in printed form, be sure to click into the discussion below.
Massively under-reported science story because there's so much going on right now but…it turns out that we might have figured out what's causing this very scary spike.
Quick thread, on how WE'VE BEEN ACCIDENTALLY GEOENGINEERING FOR DECADES…but then we stopped: pic.twitter.com/pLWzgOr8C7
— Hank Green (@hankgreen) August 4, 2023
Bottom line: Have we been geoengineering accidentally for decades? Hank Green thinks so. Now he points to sulfur dioxide as a possible road to (temporary) cooling. Btw, in case you’re wondering, Hank has been undergoing chemotherapy for cancer. Hence the beanie. Love you, Hank!
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