Resumen
An update is given of a previous paper by the same title, an explanation is given of the way greenhouse gases operate to raise the surface temperature of a planet. The paper in general is designed to be understandable to a wide range of disciplines. The argument is advanced that the role of radiative transfer has been overemphasized relative to other climatological processes and, in particular, that the roles of deep convection in the tropics and of evaporation from tropical oceans have been underemphasized and inadequately modeled in our calculations of climatic effects of increased CO2 to date.