The idea of manually tampering with our atmosphere to combat climate change, such as by seeding clouds with reflective particles to dim the Sun, remains extremely controversial. These acts of geoengineering could deliver us from climate doom, the thinking goes, or backfire spectacularly in ways we never anticipated — which is why scientists are proceeding with caution.
But to an extent, something like this is already happening on a global scale. In a new study published in the journal…