This story was originally published by Wired and is reproduced here as part of the Climate Desk collaboration. In the skies over Al Ain, in the United Arab Emirates, pilot Mark Newman waits for the signal. When it comes, he flicks a few silver switches on a panel by his leg, twists two black dials, then punches a red button labeled FIRE. A slender canister mounted on the wing of his small propeller plane pops open, releasing a plume of fine white dust.