Pacifica Tribune, Letters to the Editor, 6/20/12. "Global warming" by John Blanchard
This phenomenon of absorbing and reflecting heat can also be illustrated by a brick wall in sunlight. The brick absorbs the heat, warming it, but the heat can also be felt standing in front of the wall as it radiates out. This is infrared radiation. Virtually all solid objects have the ability to radiate heat in this way.
In the natural world the Earth is in balance with sunlight received and heat reflected as infrared radiation.
Representing the glass panes of the greenhouse, the earth's atmosphere is made up of multiple layers of gases that surround the earth and are held in place by gravity. Largely these gases permit heat from the earth to be radiated back out to space thus cooling the planet. But some gases are referred to as greenhouse gases because they absorb radiated heat and arrest its escape to outer space just as the panes of the greenhouse trap heat and create warmth.
|Just a little smog|
This fact is undisputed amongst the greater world's scientific community. The actual effects of global warming on all of us and the insidious denial of these inconvenient truths will have to be for another post."
Posted by Kathy Meeh