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What is fog?
Fog is a cloud close to the ground. Fog forms when warm, wet air cools down. Because where I live now is next to the ocean, so there is plenty of water, and sheltered from the wind by the mountains so that water doesn’t easily blow away.
Why is it so mysterious?
Lately, the fog has made it difficult to see the stars at night. On cool nights when the ocean mist is walled in by mountains like a bowl, the sky turns pitch black. Fog is one of the most difficult weather patterns to predict (guess). It can seem to appear and disappear randomly. I remember one small street in my neighborhood back in Illinois where thick fog would gather, even when there were no other clouds in sight. Because fog is so mysterious, I wonder if there has always been the same amount of fog in the world.
Is there less fog than there used to be?
Weather scientists believe that as air pollution is less than it used to be, the amount of fog in the world is going down. Less pollution sounds like a good thing, right? But less fog also means there is less water in the air and less shade from the sun, making certain areas warm up and dry out more. It can even cause droughts. Less water in the air also means less protection from the rays of the sun, causing global warming to happen faster. It might be that old factories were harming the earth and protecting it at the same time.