Expert: Tom Whiting - 1/21/2010

Question
What are the main sources of human-generated aerosols and what kind of effects do these aerosols have on temperature in the troposphere?

Answer
An aerosol is defined as a suspension of either a droplet or a solid in a gas, in this case, the air. So humans put out 1. methane, 2. carbon dioxide, and 3 water vapor droplets.
(Some of us also produce cigarette smoke on occasion, as I smoke cigarettes too).

I believe the "main sources" are from the food and water we consume and the air we breathe. We exhale carbon dioxide in small amounts, although this has been deemed an unexceptable gas to the
USA EPA... we are now allowed to inhale, but we are breaking the law everytime we exhale!
(That was a smart move, Eh?)  We also exhale small amounts of liquid water droplets at times,
and small amounts of methane gas, also called flatulance I believe.

Even more "polluting" are the 25 billion head of bovines around the world, (not to mention all
the other lifeforms on the planet) far exceeding what 6 billion humans excrete.  But all this is miniscule compared to all the forest fires, lava flows from volcanoes, the salt mist coming off the world's oceans, the incoming meteoroids (tons per day BTW)...compared to everything else, our human output is barely measureable let alone catastrophic. It's only our ego-centric view of ourselves that we think we're "that important".

The tropospheric temperature varies so much around the world, that it's nearly impossible to
attribute one effect of temperature. The main influence of tropospheric temperature is the sun,
and the Earth's axial tilt. Other sources may have a minor influence, but these pale into
insignificance when compared to solar input... so much so that it would be very difficult,
if not impossible, to isolate one singular cause or event, unless it's of major importantance...
for instance, if the massive 50 mile wide Yellowstone megavolcano was to explode again, like
it did 640,000 years ago, (it's way overdue) that would drastically change our troposphere, and probably launch us into the next Ice Age... which is overdue by about 1000 years, as we're on borrowed time from the next ice age.  A small nuclear exchange could also do the same thing, as could an incoming asteroid impact of say, 1/2 mile wide or greater. OR 4 or 5 regular size volcanoes explosively erupting at the same time could do the same.  Fortunately most of those
mega-events are exceedingly rare.
Hope this helps,
Clear Skies,
Tom Whiting
Erie, PA