Simple radiative models for surface warming and upper-troposphere cooling



A simple model of greenhouse-gas radiative processes intended to make the surface-warming effect of water-vapour and CO2 absorption more readily understandable leads to a conclusion that the greenhouse gases also cool the upper troposphere. The results from the simple model are compared with experimental observations, and a functional form for the decline of vertical convection and water-vapour radiation near the tropopause is derived from previously unexplained high-altitude cooling-trend data. A possible reason why global climate models do not show the observed upper-troposphere cooling trend is tentatively suggested. Copyright © 2008 Royal Meteorological Society