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Someone asked about temperatures in the upper atmosphere, and if there had been any real change? I can only speak for the time I was in Nevada and Arizona, and I've been retired for close to eight years now and the memory ain't quite as good as it used to be. First off, it's a bit nippy way up yonder. Between 30 and 40 thousand feet temperature range from minus30 degrees Celcious to minus 50 degrees Celcious, depending on the time of year. As I recall, the colder tempertures up there occur in the summer and the warmer in the winter. it's not all that surprising when you take account that in the winter there is a lot of cloud cover a good part of the time and heat from the sun is reflected back into space off that cloud cover. Say you get a big snow storm and it's relatively warm for the time of year. Then a strong high pressure area moves in pushing the clouds out and that open sky lets what heat there is escape, reflecting off that snow. I personally have seen a temperature at midnight go from +32 degrees F. to -36 degrees F. in just a little over seven hours after the coud cover moved out. The heat will rapidly rise warming the upper atmosphere, maybe raising it about 5 degrees C. over a period of time. You won't get that effect in the summer. But then again, in the summer you won't have the cloud cover to give you a modicum of "shade".
Another big source of global warming are cities. As we become more urbaized, citied grow larger. When I move to Arizon, Tucson and Pima county had maybe 500,000 people, give or take. Now the population is over 1,000,000 and growing like a weed. All the nearby areas I used to hike and hunt a few rabbits is now wall to wall houses. Tucson and it's close neighbors have created a monstrous heat island. Look al L.A. and it's eviorons. hell, look at the growth around any big city and it's suburbs. More massive heat islands. I'd venture to guess a goodly part if the problem comes from the fact that we're blacktopping the planet to death, world wide.
At one time, it was said that a squirrel could start at the Atlantic Ocean and travel all the way to the Missippii River and NEVER touch the ground. Now he's have to take the Interstate. Where are all those trees today? Even the rain forest of the Amazon are disappearing rapidlt to the tune of something like, IIRC, 20,000 Hectares daily.
Just how much of the problem is man made I can't say. Man sure ain't helping. Still, this old ball in space has been around for quite a while, and I think it'll be here in some form long after we're gone. I am more inclined to going along with the bigger part of the problem is the sun going through a warming cycle. It's happened before in the past where daytime gtemps ran around 130 degrees, so who's to say it's not happening again. It may take us a while for it to reach that point in which case we humans had best learn to adapt to the changing conditions.
Paul B.
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