Dear
I do not know with certainty what causes the warming of the climate at present. I do see no perfect correlation with atmospheric carbon dioxide content in the distant past though, or even perfectly so in the past half million years (  http://www.exploratorium.edu/climate/cryosphere/data2.html. ) While increased atmospheric carbon dioxide would probably increase temperature, in early Permian, the first major rise in carbon dioxide FOLLOWED a temperature rise. I suspect that what happened back then was that a rise in temperature permitted cellulose digesting insects to move toward the poles, and thus increase release of carbon dioxide. When there was a drastic rise in carbon dioxide about 5 million years later, the temperature started its main rise about 2 or 3 million years after that [Montanez]. While the temperature rise was not caused by the carbon dioxide at first, I suspect that clearing the soil of mulch and vegetative cover by the insects, which enabled higher soil temperatures, was a large part of it. Subsequent changes in carbon dioxide showed no close parallel to temperature either.
There is considerable concern about climate change. This is understandable, especially if it happens rapidly. It is usually assumed that it is from carbon dioxide increase (  http://www.exploratorium.edu/climate/atmosphere/index.html. ). This is without a doubt part of it. However, I suspect the major part of it these days is the removal of vegetation to create annual farms, roads, buildings, denuded land, and desertification. You can easily confirm this phenomenon by touching a stone walk in full sun and adjacent grass, and noting the dramatic difference in temperature. In an area in Oregon where fire bared the soil, there was a temperature difference between burned and unburned adjacent areas that rose to as much as 20 degrees centigrade [Running]. Also leaves in warm climates have adaptations in warm climates that lower leaf temperatures toward their optimum photosynthetic temperature ( http://www.nature.com/nature/journal/v454/n7203/full/nature07031.html )[Brent], which should lower climate temperature a little.
Denudation could be easily reversed by planting shade trees along roadways, substituting nut and fruit trees for annual crops, and growing vegetation on rooftops. If not, no problem, we will have plenty of room for the people of southern Florida on our Canadian and Siberian farms.
Everyone is concerned about the atmosphere being increased in carbon dioxide and decreased in oxygen and not without reason. However an answer to a question we have not been asking is; "We should not be using our carbon fuels for so trivial a purpose as to merely generate heat and therefore electricity or non aviation transportation in a world where every week the sun beams down enough energy on the state of Arizona alone to supply the whole world with non transportation energy during that time". Those fuels should be devoted to chemical stock and aviation. Burning carbon is akin to burning furniture to keep warm. Oil will probably run out in another hundred years or so and practical coal probably in another two or three hundred or so. What do we have planned for the remaining million years this nation is scheduled to survive? Our constant drum beat about not being dependent on foreign oil is 180 degrees off. If we were really greedy we would use foreign oil as much as possible. If a major war should loom after our oil runs out we will be left high and dry, and maybe defeated.
But if our oil policy seems foolish, our atomic fuel policy must seem like insanity by comparison. At least the carbon will still be on the surface of the earth, extremely expensive to turn into chemicals, but not impossible. Uranium once burned will be gone forever. Our progeny will curse us if they come across a very valuable use for uranium and it is gone. If that purpose were to be the only practical way to get rid of a meteor scheduled to destroy the earth, for instance, they will be cursing us with their dying breath. They will look back on our problems with those jerks in Afghanistan with fond nostalgia.
It is often said that we can not tap the sun’s energy without further expensive research. This is not so. We already know how to make linear parabolic mirrors and numerous effective ways to make heat generated vapor engines as well as photovoltaic cells. The only thing stopping us is oil and coal selling for, probably, a third of what it would cost to manufacture it out of carbon dioxide or limestone.

Below is by Richard Charles Antolinez.
“Food prices are soaring because corn is being used for ethanol production, and food riots are breaking out in many places. E10 or 90% gasoline 10% ethanol is supposed to only reduce fuel mileage by 2% to 3%. I don’t know how they came by their numbers, but I assume they simply deduced that ethanol has about 30% less British Thermal Units, and since it made up of 10% of E10, then about a 3% reduction in mileage could be expected. This is the way the morons in labs think, especially when their job depends on it. Many vehicles are seeing a 10% or more drop in fuel mileage. You see no vehicle is designed to run on E10, and it simply is out of tune for E10. So it is more than just the BTU difference between the E10 blend and straight gasoline. Many owners have clogged the internet with such complaints; fleet owners have reported as much as an 11.9% drop in mileage. Ethanol tends to act as a combustion inhibitor when mixed with gasoline. Did you know for every gallon of ethanol produced, the American taxpayer pays .55 cents to the producers? Plus the government has another gaggle of subsidies I won't get into.
In terms of energy output compared with energy input for ethanol production: Corn requires 29 percent more fossil energy than the fuel produced. Switch grass requires 45 percent more fossil energy than the fuel produced. Wood biomass requires 57 percent more fossil energy than the fuel produced. These figures don't include the fact that ethanol has to be shipped by truck, because it is incompatible for current pipe-lines.”
You may see a procedure described using sodium silicate treated plywood and wooden pipes to make an inexpensive forest fire break (  http://www.angelfire.com/nc/isoptera/index.html ). You may see an article that describes how the removal of vegetation by evolution of termites at the close of the Permian may have caused a dramatic, even ruinous, rise in temperature in the Triassic in (  http://www.angelfire.com/nc/isoptera/permian.html )
You may see the above article in  http://charles_w.tripod.com/climate.html

REFERENCES
----Brent R Helliker Richter SL 2008 Subtropical to boreal convergence of tree-leaf temperatures. Nature 454, 511-514.
----Montanez IP Tabor NJ Niemeier D DiMichelle WA Frank TD Fielding CR Isbell JL Birgenheier LP Rygel MC 2007 CO2-forced climate and vegetation instability during late Paleozoic deglaciation. Science 315; 87-91.
----Running SW 2008 Ecosystem disturbance, carbon, and climate. Science 321; 652-653.