An attempt is made in this paper to find the relationship of long-term evolutional and periodical changes on the basis of a general convection model in the mantle and related circulation of substance in hydroatmosphere. These long-term processes are superimposed by cyclic climatic, biotic, and eustatic crises associated, on the one hand, with mantle plums, and on the other, with cyclic changes in orbital parameters (Milankovich'es cycles). Combined intensity curves of various processes are given for Paleozoic, Mesozoic, and Cenozoic as well as examples of short-cycle variations, including climatic changes on Lake Baikal.
