A Dynamical Stabilizer in the Climate System: A Mechanism Suggested by a Simple Model and Supported by GCM Experiments and an Observational Data Study

Abstract

A fundamental problem in climate research is that of explaining how the Earth’s climate remains stable on very long time scales. Positive feedback mechanisms such as the ice-albedo feedback and the lower tropospheric water vapour/infrared radiative feedback on sea surface temperature perturbations are known to exist which could, in principle, drive the climate system far from its observed mean state even in the absence of any external forcings. Extreme scenarios that have been envisaged are a completely ice-covered earth on the one hand and a runaway greenhouse such as appears to have occurred on Venus on the other.