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 water (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 movement of cold water along the underwater slope to maximum depths. Cooling of deep and near-bottom waters caused by forced convection is compensated during other seasons of the year by eddy heat flux directed toward the bottom. On a long-term basis, vertical temperature profiles in deep waters remain constant.