For Iceland's farmers, though, the problem is very much on the ground.
Farmers across the region have been scrambling to protect their herds from inhaling or ingesting the ash.
The vast majority of the country's farming is based on herding cattle, horses and sheep, so the stakes are high.
Near Skogar, south of the Eyjafjallajkull volcano, the ash blew down the mountain, blotting out sunlight and covering everything in a thick gray paste.
Berglind Hilmarsdottir, a dairy farmer, teamed up with her neighbours at the weekend to round up her 120 cattle and get them to shelter.
"The risk is of fluoride poisoning," she said. "The best we can do is put them in the barn, block all the windows and bring them clean food and water as long as the earth is contaminated."