Thursday, March 15, 2007

GLOBAL DRYING - Super Drought?

Click the title above to hear my 12 minute summary on global drying news.

Don't get me wrong. The science says that a warmer world will hold more water vapor in the atmosphere. And water vapor is also a potent greenhouse gas itself! You can see the positive feedback loop there.

All that water has to come down somewhere, and tons have dropped on the Pacific Northwest lately. I feel like an amphibian here. But that's an exception. A whole belt around the tropics, and extending up into the U.S. Southwest, and the Australian South, are set to dry out into recurring droughts.

That's in the news all over. CNN reports that a leak of the upcoming IPCC report in April (to AP Press) - predicts billions of people - that BILLIONS - could face water shortages by the end of this century.

We're already seeing a super drought in southern Australia. The bush keeps burning up, and former farming land turns into dust. The rainfall there has shifted Southward toward Antarctica, as warming climate disturbs the weather system.

You don't need to be told about the Sahel of Africa. There are already millions of environmental refugees from spreading deserts and drought-lands caused by first-world carbon spewing uncontrolled into the atmosphere. Tim Flannery blames the Darfur tragedy on Europe's smokestacks and tailpipes.

Even the Amazon rainforest has begun to dry out, with reports of rivers shrinking to a fraction of their normal size. The great rainforests may become grass lands - and all their carbon will be released, to our peril.

Then Joseph Romm, author of the blog Climate Progress, writes an article on "the interglacial super drought" in the U.S. Southwest. Agriculture, and eventually who cities of people in Arizona, Nevada, Colorado and New Mexico will be hit by drought.

Even Los Angelese residents know what I am talking about. So do people near the mountains in China. A new article in the journal "Nature" explains that a type of rainfall formerly caused as hot air cools around the mountains, is greatly reduced. That's because the type of smog particles coming from diesel motors, burning bio-mass, and agricultural fertilizers - is inhibiting the formation of raindrops.

Weather experts suspected that smog was reducing rainfall. The mountain-type rain in California has been reduced between 10 to 25 percent in the last 30 years or so. Now there is scientific evidence to prove it.

The study was done in China, where air pollution is so severe. On a particular mountain, blessed to receive the smog of a great city, raindrops were unable to form. The mountian ecosystem, and all the residents of the valley below, lose the rain they need.

Perversely, when human-made dust in the air ("aerosols") travels over the Pacific, picking up larger particles of salt as well - they drop sheets of heavy rain on the Pacific NorthWest. What fails to fall in one area, is moved elsewhere, to provoke heavy flooding.

Heavy rainfall events will increase in some parts of the world, while droughts strike others.

We're just beginning to understand all this. A lot of science is hot of the press, as they say.

James Lovelock has a map of what an over-heated world would look like. Sure enough, the tropics are mostly deserts - both on land, and under the sea! The green habitable areas are much closer to the poles, especially around the Arctic Sea.

The planet has been in that kind of a state before, in cycles that seem to take many millions of years to develop - except we're pushing it that way in just one or two human lifetimes. Apparently, Nature never expected one of its creatures to drag out hundreds of millions of years of carbon, and burn it all!

Dig into this. Global drying will hit in a wide belt, even while other areas experience Biblical floods.


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