Mathematics & Physics 2015, 8(2), 148–156 УДК 517.9 Baroclinic Seiches for Three-Layer Density Stratification in the Basin of Rectangular Shape Victor M.Belolipetskii Institute of Computational Modelling SB RAS Akademgorodok, 50/44, Krasnoyarsk, 660036 Institute of Mathematics and Computer Science Siberian Federal University Svobodny, 79, Krasnoyarsk, 660041 Russia Svetlana N.Genova∗ Institute of Computational Modelling SB RAS Akademgorodok, 50/44, Krasnoyarsk, 660036 Russia Andrey G.Degermendzhy† Alexander P.Tolomeyev‡ Institute of Biophysics SB RAS Akademgorodok, 50/50, Krasnoyarsk, 660036 Russia Received 25.01.2015, received in revised form 17.02.2015, accepted 24.03.2015 The problem of linear baroclinic seiches in rectangular basin is considered. <...> It is supposed that density is stratified into three layers. <...> It is shown that one-dimensional model allows one to determine the positions of thermocline and halocline. <...> The model also allows one to determine the values of temperature and salinity in the surface and bottom layers with satisfactory accuracy. <...> Fluctuations of temperature and salinity in pycnocline are estimated by calculating parameters of baroclinic seiches. <...> The results of calculations and measurements in Lake Shira are compared. <...> Keywords: internal seiche, three-layer stratification, vertical distribution of temperature and salinity of water, Lake Shira. <...> A temperature regime of a reservoir is determined by the flow of heat through the water surface and by heat exchange with the surrounding water masses, that is, it is carried out by advection and turbulent diffusion. <...> The one-dimensional mathematical model to describe vertical distribution of water temperature and salinity was proposed [1,2]. <...> In the one-dimensional approximation the vertical distributions of temperature and salinity are determined by the vertical exchange of heat and mass. The vertical turbulent exchange coefficient is defined by the Prandtl-Obukhov formula and by the Ekman approximation for wind currents. <...> Density stratification of a lake is formed due to heating of the upper water layer and stratification in halocline. <...> In stratified reservoirs internal waves are formed. <...> All rights reserved c – 148 – Victor M.Belolipetskii, Svetlana N.Genova, Andrey G.Degermendzhy,Alexander P.Tolomeyev Baroclinic . travelling waves or standing waves. <...> Standing internal wave (or baroclinic (internal) seiche) is <...>