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Northern Hemisphere Pollution a Cause of '80s Africa Drought
vinces99 writes "Decades of drought in central Africa reached their worst point in the 1980s, causing Lake Chad, a shallow lake used to water crops in neighboring countries, to almost dry out completely. The shrinking lake and prolonged drought were initially blamed on overgrazing and bad agricultural practices. More recently, Lake Chad became an example of global warming. But new University of Washington research shows the drought was caused at least in part by Northern Hemisphere air pollution. Particles from coal-burning factories in the United States and Europe during the 1960s, '70s and '80s cooled the entire Northern Hemisphere, shifting tropical rain bands south. That meant that rains no longer reached the Sahel region, a band that spans the African continent just below the Sahara desert."
If that was caused my industrial pollution in the U.S. 30-odd years ago, what can we expect from the pollution China is dishing out?
vos nescitis quicquam, nec cogitatis quia expedit nobis ut unus moriatur homo pro populo et non tota gens pereat.
Burn more coal in the southern hemisphere, and push the rain back north...
“He’s not deformed, he’s just drunk!”
This goes much further into explaining some of the variance, both seasonal and longish-term (only goes back to the Fifties), of water table levels in the entire Chad basin - a system that covers a tenth of the entire African continent, not just a relatively small body of surface water. The human impact, according to that paper, accounts for about one twentieth of the total variance in the system but as much as 40% of the surface area of the lake itself (and up to half the volume), with most of that variance originating upstream in tributary river systems. AGW is barely even considered (or even mentioned, going by a quick scan down the paper), since the effects of AGW, if it even exists, have not been or cannot currently be measured because until it is properly defined, nobody even knows what to look for. It does deal with precipitation, which has had a bit of a lull over recent decades (1985-1994 being particularly dry years), but again this deals with the entire system not just the lake.
Operation Guillotine is in effect.
So if, say, 50% of scientific papers are "intellectually honest," and 97% of scientific papers addressing climate change conclude that anthropogenic factors are the main drivers of variance over the last century or more, then how can you not "buy into the global warming camp"?
Isn't the whole "anti-climate change camp" devoted to the notion that there is such a thing as major, wide-spread actions without consequences, contrary to your major assertion? Because on the level of global climate, somehow man's actions are perpetually too small to effect it, or a deity will counter any potential harm we do, or the planet will magically turn every potential disadvantage to advantage, or the like?
"with their freedom lost all virtue lose" - Milton
This sort of confusion is what psuedo-skeptics are are taking advantage of when they claim an ice age was predicted in the 70's. Coal gives off (among other things), SO2, CO2 and soot. Sulfur causes cooling, acid rain, and deadly "pea soup fog", Soot causes warming, lowers albedo, and accelerates ice melt. CO2 causes warming and ocean acidification. Some of the soot and sulfur was cleaned up by various clean air acts in the 60's & 70's after the death toll from "pea soupers" in London and other European cities started getting difficult to ignore. Sulfur emissions (and acid rain) were dramatically 20 odd years ago when Regan instituted a cap and trade treaty on sulfur emissions, similar to those being proposed for CO2 (ironic, huh?).
Having said all that, climate scientists don't really talk about cooling or warming, they talk about +ve and -ve forcing and feedback, two forcings with different signs can indeed cancel each other out. To confuse matters further CO2 can be both a forcing (humans, volcanoes) and a feedback (melting permafrost, increased bushfires). Feedbacks have far more uncertainty associated with them than forcings. When everything is taken into account you can work out a figure called "climate sensitivity" (CS). The CS in models compares very well with the CS derived from geology and really hasn't changed that much since the 70's.
All this is just a sample of the complexity that adds up to ripe pickings for people who have no problem deliberately misinforming the public for personal gain.
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.