In this study, we present an analysis of the hydrodynamic processes under ice cover in the largest lagoon in Europe – the Curonian Lagoon. By applying a finite element numerical modelling system (SHYFEM) and remote sensing ice cover data, the residual circulation, water fluxes through specific areas of the lagoon, saltwater intrusions, and water residence time (WRT) were investigated. The results, taken over an 11 year period, show that ice cover affects the circulation patterns in the lagoon by forming and shifting different gyre systems. Different circulation patterns are observed throughout all the meteorological seasons of the year. Since ice decreases circulation, water fluxes also decrease, especially in a cross-section in the middle of the lagoon, where the ice-cover suppressed wind-stress has a higher impact on the water movement rather than it has in the north. The presence of ice cover also decreases the salinity of the water in the northern part of the lagoon. In general, the salinity in the water column-averaged over different periods is vertically uniform, however, a slight increase of salt concentration can be observed at the bottom layers in the Klaipėda Strait, where the difference of >1 PSU between bottom and top layers shows up on average 130 hours per year. The ice cover also decreases the saltwater intrusions into the lagoon by nearly 14 days per year. The increase of WRT is most prominent after long ice cover periods, away from the river inlets, especially in the southern part of the lagoon, where without the help of the wind action, water takes a longer time to renew than in the northern part.

在这项研究中，我们对欧洲最大的泻湖库尔斯泻湖中的冰盖下的水动力过程进行了分析。通过应用有限元数值模拟系统（SHYFEM）和遥感冰盖数据，研究了残留环流，通过泻湖特定区域的水通量，盐水侵入和水停留时间（WRT）。历时11年的结果表明，冰盖通过形成和移动不同的回旋系统影响了泻湖的循环模式。在一年中的所有气象季节中，观察到不同的循环模式。由于冰会减少循环，因此水通量也会减少，尤其是在泻湖中部的横截面中，那里的冰盖抑制了风应力，对水运动的影响比北部更强。冰盖的存在还降低了泻湖北部的水盐度。通常，在不同时期内水柱平均的盐度在垂直方向上是均匀的，但是，在克莱佩达海峡的底层可以观察到盐浓度略有增加，底层和顶层之间的差异> 1 PSU每年平均显示130小时。冰盖还可以每年将咸水入侵泻湖的时间减少近14天。在漫长的冰覆盖期之后，WRT的增加最为显着，远离河流入口，尤其是在泻湖的南部，那里没有风力的帮助，