The influence of wind on the development of a thermal bar and currents in reservoirs of different depths during Ice Cover Melting

The influence of wind on the development of a thermal bar and currents in reservoirs of different depths during ice cover melting was studied using mathematical modeling. It is shown that the reservoir depth, as well as the wind velocity and direction, determine the behavior and lifetime of vortex structures in a reservoir that form on both sides of a thermal bar, as well as the location of their convergence zone and the 4$^{\circ}$C isotherm. The dominant mechanisms of the instability of water masses in reservoirs of different depths under wind action on their surface are identified. It is shown that the higher wind speed is, the deeper the reservoir should be in order to get the zone of divergence of water masses close to 4$^{\circ}$C isotherm. In this situation it is justified to use a classical interpretation of a thermal bar as a region of water convergence near 4$^{\circ}$C, unlike shallow reservoirs where even slight winds lead to the significant divergence of these zones.