A Mesoscale Air·ice·ocean Feedback Mechanism for the Ice Drift in the Marginal Ice Zone

Ice drift in the marginal ice zone (MIZ) is a very important feature of air-ice-ocean interaction at high latitude. Thermally generated surface winds, blowing from ice to water (ice breeze) with some deflection due to the eart.h rotation, force the ice drift and ocean currents near the MIZ. By changing the surface temperature Cilradient, the ice motion and the ocean currents feed back on the surface winds. A coupled air-ice-ocean theoretical model for the MIZ is employed to discuss the ice drift pattern with such a feedback mechanism. The steady-state solutions show that an off-ice and divergent wind field not only producee a dilation of the MIZ (as people generally think), but also generatee a compaction of MIZ for aome circumst.ances. An ice divergence/convergence criterion is found. The time-dependent solutions show that the ice motion exhibits two bifurcations. First, it bifurcates into decaying and growing modes. Second, the growing mode bifurcatee into non-oscillatory and oscillatory IItates. Finally, the model predicts the ice edge upwelling.