Global Warming and CO2

This article in the AAPG Bulletin: Climate change: Conflict of observational science, theory, and politics, should be required reading for anyone concerned about whether global warming is being caused by our industrial society's release of CO2 into the atomosphere. The case that this is true is far from certain, although many people seem to assume it is without looking at any of the data. Some of the data from this article is shown in the posted graphs seen here.

What these graphs show is that since the Cretaceous, the Earth has been in a major cooling trend. In recent times (the Pleistocene) extreme cooling is evident (the ice ages) with short, warm interglacials. We are currently in the longest interglacial of this time period. The current global temperature is nearly 3 degrees warmer than the temperatures in the Mediveal warm period (1000-1200 A.D.) and less than 1 degree warmer than "the Little Ice Age" (1400-1850 A.D.).

Temperature does appear to be rising since 1980, but the graphs shows it may be driven by increasing irradiance from the sun. Additionally, from about 1940 to 1980 temperature was going down, even while the sun's irradiance spiked. Global war and nuclear tests may be responsible for this, but here we speculate that man's influence is driving the temperature down and not up.

The final graph details the cooling trend over the last 10,000 years. What this graph tells me is that the real and strong trend is cooling, leading us toward a new glacial epic. The minor heating evident only since 1980 is not really significant and unlikely to continue, even enough to return global temperature to where it was in Medieval times. The precipitous drops in temperature characteristic of the Pleistocene epoch are the danger we should actually fear. Perhaps it is only our release of CO2 into the atomosphere that has kept this tiger at bay.