ABSTRACT
Cloud cover is an important factor which determines the geographical distribution and the annual change of the climate regime. Analysis of the sensitivity of climate to cloud characteristics, based on numerical modelling and diagnostic studies, has now become of great concern. As Henderson-Sellers notes, three independent sources of information on climate show that the increasing total cloud amount must cause a climatic cooling. Firstly, from satellite data, an increase of the cloud amount leads to a decrease of the Earth radiation budget. Secondly, it follows from surface meteorological observations for the last hundred years that in the periods of climate warming the cloud amount grew, but in the presence of clouds the surface air temperature was lower than it ought to have been in clear-sky conditions. Thirdly, results of numerical modelling agree with observational data, although they are controversial.
