Mathematical modelling of Lake Baikal hydrodynamics

The paper summarizes our work on numerical modelling of Lake Baikal hydrodynamics. Two basic models are briefly described here. One of them is a time-dependent, free-surface model of variable density. As a deep lake is discussed, a nonlinear equation of state is used in which the density is a function both of temperature and pressure. One of the main applications of the model was for the climatic circulation of the lake. The scenario approach was applied for this purpose. The parameterization of atmospheric forcing was carried out by means of statistical methods on the basis of a meteorological classification of the pressure and wind fields above the lake. The second model is intended for the direct modelling of the convective movement in a deep temperate lake. The non-hydrostatic (NH) assumption is involved in it. Water is considered to be compressible. The results of numerical experiments with the 2D version of the NH model are discussed. The focus is on the features of the thermal bar in Lake Baikal in connection with the deep water renewal.