CO2-induced global warming: a skeptic's view of potential climate change

Over the course of the past 2 decades, I have analyzed a number of natural phenomena that reveal how Earth's near-surface air temperature responds to surface radiative perturbations. These studies all suggest that a 300 to 600 ppm doubling of the atmosphere's CO 2 concentration could raise the planet's mean surface air temperature by only about 0.4C. Even this modicum of warming may never be realized, however, for it could be negated by a number of planetary cooling forces that are intensified by warmer temperatures and by the strengthening of biological processes that are enhanced by the same rise in atmospheric CO 2 concentration that drives the warming. Several of these cooling forces have individually been estimated to be of equivalent magnitude, but of opposite sign, to the typically predicted greenhouse effect of a doubling of the air's CO 2 content, which suggests to me that little net temperature change will ultimately result from the ongoing buildup of CO 2 in Earth's atmosphere. Consequently, I am skeptical of the predictions of significant CO 2 -induced global warming that are being made by state-of-the-art climate models and believe that much more work on a wide variety of research fronts will be required to properly resolve the issue.