DEEP VENTILATION OF LAKE BAIKAL WATERS DUE TO SPRING THERMAL BARS

Increase of density due to mixing (cabbeling instability) in a spring thermal bar in Lake Baikal results in the sinking of cold sur-face wat er (T = 3.2-3.4-degrees-C, w = 0.3 cm s-1) below the profile of T(md). This density increase generates forced convection and subsequent move ment of cold water along the underwater slope to maximum depths. Cooli ng of deep and near-bottom waters caused by forced convection is compe nsated during other seasons of the year by eddy heat flux directed tow ard the bottom. On a long-term basis, vertical temperature profiles in deep waters remain constant.