Revised description for clarity:
Photos of near-earth clouds of smoke, steam, fog, smog, or other visible particle clouds that are close to the ground. Even dust in the air, pollen, whatever. Photos of puffy clouds in a blue sky and storm clouds rolling in need not apply.
Original post: A suggestion from Fark’s Dissemination Monkey:
I was thinking you could do a theme like called something like “the air down here” or “near-earth clouds” or something. The idea would be photos with smoke, steam, fog, smog, etc. Some sort of visible particle clouds that are close to the ground. Even dust in the air, pollen, whatever.
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