Constant Conservative

Willis Eschenbach does another excellent job of explaining a difficult matter with regard to climate. After noting that he often hears people say something along the lines of “well, simple physics tells us that more CO2 equals warming” he dives in:

Unfortunately, while the physics is simple, the climate is far from simple. It is one of the more complex systems that we have ever studied. The climate is a tera-watt scale planetary sized heat engine. It is driven by both terrestrial and extra-terrestrial forcings, a number of which are unknown, and many of which are poorly understood and/or difficult to measure. It is inherently chaotic and turbulent, two conditions for which we have few mathematical tools.

The climate is comprised of five major subsystems — atmosphere, ocean, cryosphere, lithosphere, and biosphere. All of these subsystems are imperfectly understood. Each of these subsystems has its own known and unknown internal and external forcings, feedbacks, resonances, and cyclical variations. In addition, each subsystem affects all of the other subsystems through a variety of known and unknown forcings and feedbacks.

Then there is the problem of scale. Climate has crucially important processes at physical scales from the molecular to the planetary, and at temporal scales from milliseconds to millennia.

As a result of this almost unimaginable complexity, simple physics is simply inadequate to predict the effect of a change in one of the hundreds and hundreds of things that affect the climate.

Then he introduces a couple of thoughtful experiments to help explain why he is saying that the systems’ interplay is simply too difficult to guess correctly. Please, go read it all–you’ll be glad you did.