The Influence of the Duration of Wind Impact on the Formation of Currents and a Thermal Bar in a Freshwater Reservoir over the Period of Melting of the Ice Cover

Abstract

The impact of wind of different strengths, directions, and durations on the development of a thermal bar and accompanying currents in reservoirs over the period of ice cover melting was studied using mathematical modeling. It is shown that as the duration of the wind impact on the reservoir increases, the role of energy exchange at the water-air interface in the formation of currents in the reservoir increases. The passage of surface waters through the temperature of maximum density (4°C) leads to the formation of a thermal bar and convective structures to the right and to the left of it. In this case, the increase in the energy exchange as the duration of the wind grows occurs with different degrees of intensity on different sides of the thermal bar. In certain hydrometeorological situations (when the wind is directed offshore) this can increase the intensity of the convective vortex in the deep part of the reservoir and weaken it in the shore part, which will slow the propagation of the thermal bar towards the center of the reservoir.