Why does ice form regularly in the northwestern Black Sea during winter?

Ice forms regularly in the northwestern Black Sea during winter primarily due to the region's steppe climate, which is characterized by cold winters and exposure to northern air masses.1

During the winter months, the area is significantly cooled by spurs of the Siberian anticyclone, a high-pressure system that generates strong currents of cold air. This cooling effect is further intensified by the invasion of polar continental air, which is frequently accompanied by strong northeasterly winds and rapid temperature drops. These conditions cause the water temperature in the northwest to fall to approximately 31 °F (-0.5 °C), facilitating regular ice formation in this part of the basin.12