The Shakespeare Conference: SHK 24.0253 Wednesday, 15 May 2013
Date: May 15, 2013 4:07:21 AM EDT
Subject: Re: SHAKSPER: Fog-Smog
>Fog begins to form when water vapor condenses into tiny liquid
>water droplets in the air. . . . Water vapor normally begins to
>condense on condensation nuclei such as dust, ice, and salt
>in order to form clouds. Fog . . . is a stable cloud deck . . . .
>Cloud condensation nuclei . . . are small particles . . . on which
>water vapour condenses. Water requires a non-gaseous surface
>atmosphere, this surface presents itself as tiny solid or liquid
>particles called CCNs. When no CCNs are present . . . in
>above freezing temperatures the air would have to be
>supersaturated to around 400% before the droplets could form.
>A typical raindrop is about 2 mm in diameter, a typical cloud
>droplet is on the order of 0.02 mm, and a typical cloud
>condensation nucleus . . . is on the order of 0.0001 mm . . .
>or greater in diameter. The number of cloud condensation
>nuclei in the air can be measured and ranges between around
>100 to 1000 per cubic centimetre. There are many different
>types of atmospheric particulates that can act as CCN. The
>carbon from grassland or forest fires, sea salt from ocean
>wave spray, soot from factory smokestacks . . .
Or tiny bits of soil, vegetable matter and just about anything we can’t see. Saying this, however, does not blame fog or any other weather phenomenon on human pollution. There was plenty of snow, ice crystals, hail and rain drops on Earth long before man appeared and started burning wood and charcoal to keep warm and cook food.