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collegeguy
2005-Sep-24, 01:52 PM
Since there`s a lot of discussion about environment pollution, global warming etc. I thought this might be something to talk about.

Probably most of you heard about global dimming. This process is known for quite a while but became a big discussion point in science after 9/11, because there was no air traffic all over the world after the attacks for some time. But first things first. The theory of global dimming says that tiny airborne particles reflect the sunlight. These particles are the result of the burning of fossil fuels. So as long as the air pollution continues we will not realize the actual effects of the global warming since the particles in the clouds reflect the sunlight. According to this theory global warming has been underestimated, because the temparatur has not increased significant. As there was no air traffic and thus no kerosene in the air (which has a huge impact on global dimming) after 9/11 scientists could analyse the actual global warming and there was apparently a big temperature increase.

Ironical as it may sound but with the decrease of air pollution in the future we will realize the true results of global warming. That doesn`t mean global dimming is a good thing, it has a terrible impact on humans health and also on the climate.

http://www.bbc.co.uk/sn/tvradio/pro...g_summary.shtml

http://www.bbc.co.uk/sn/tvradio/pro...ing_trans.shtml

http://www.bbc.co.uk/sn/tvradio/pro...imming_qa.shtml

What do you guys think?

Argos
2005-Sep-24, 02:03 PM
The (American) air traffic was suspended for a relatively short time after 9/11. I donīt think it caused much of an impact on the global trends.

Glom
2005-Sep-24, 02:42 PM
Actually, it was the high pressure region during in the days following 9/11 that caused the warmer weather. And there aren't large amounts of kerosene in the air. Turbines burn very cleanly compared to piston engines.

Eroica
2005-Sep-24, 04:54 PM
As there was no air traffic and thus no kerosene in the air (which has a huge impact on global dimming) after 9/11I thought it was the lack of contrails, which reflect sunlight back into space like clouds, that was the key factor?

A better study compares global dimming over Western Europe - where EU anti-pollution regulations are cleaning up our air - with global dimming over, say, South-East Asia, where there is terrible air pollution.

Note: your links all 404'ed on me!

collegeguy
2005-Sep-25, 12:03 AM
Sorry about the links, I had just checked some info on global dimming. Don't know much of it, I was hoping somebody knew more of the topic.

publiusr
2005-Sep-29, 05:09 PM
It's always something. In the 1970s, the Greens said that we would alreadly have been out of oil and that the sky would be as black as the ace of spades and we would be in an ice age. Now its Global Warming--or Global Change--as if the globe didn't change anyway.

If the temperature goes up--that's global warming.

If the temperature goes down--well, that's GW too, because you have more evap--more precip--and at the poles that's newer/cleaner/more snow that messes with the albedo and...

If the temperature stays pretty much the same--well that's global warming too--cause we see more extremes/storms, etc.

So if the temps go up--go down--or stay the same--it's our fault.

They have rigged the arguement so that no matter what happens--we did it.

It is no different than the snake oil salesman who sells a cancer victim water with food coloring in it.

If the cancer is in remission--I cured you.
If there is no change--I arrested its development/growth
If you get worse--well, you'd be dead now if it weren't for my elxir of life--so buy more!

suntrack2
2005-Sep-30, 04:52 PM
your doubt is important, about the global dimming, when the carbonic elements, carbon monoxide will spread over the sky of earth, and the thickness of it when rise, in that case we can experience the deam light on earth, though the sun is brighter thereon. today who is looking careful in respect of the global pollution !


sunil