The Control Group 

Any scientific experiment that wants to hold up to peer scrutiny has to include a control group. While you muck around with a certain set of subjects, attempting to prove your hypothesis, you keep a certain number unchanged. However, you still perform the same tests on them to use as comparison. In drug experiments, the control group is generally given a placebo to discount the affects of psychological healing.

The problem with experimenting on our environment, or attempting to prove the cause of environmental changes is that we have no control group to compare to. Or do we? The Speculist points out a Denver Post article that mentions how Mars is also undergoing global warming. When you think about it, Mars is a pretty good control group. Compared with other planets in our solar system it has about the same size and does have an atmosphere. We have robots there now capable of repoting conditions.

Futurepundit points to this report on the cycle of the sun. The Sun is More Active Now than Over the Last 8000 Years:

The activity of the Sun over the last 11,400 years, i.e., back to the end of the last ice age on Earth, has now for the first time been reconstructed quantitatively by an international group of researchers led by Sami K. Solanki from the Max Planck Institute for Solar System Research (Katlenburg-Lindau, Germany). The scientists have analyzed the radioactive isotopes in trees that lived thousands of years ago. As the scientists from Germany, Finland, and Switzerland report in the current issue of the science journal "Nature" from October 28, one needs to go back over 8,000 years in order to find a time when the Sun was, on average, as active as in the last 60 years. Based on a statistical study of earlier periods of increased solar activity, the researchers predict that the current level of high solar activity will probably continue only for a few more decades.

I wonder if there's a connection? Nahhhhh.