One theory suggests that the name comes from the fact that the sea is covered with ice most of the year. Others believe that the name originates from the whitish color of the water, reflecting the northern sky.
White sea gets frozen?
In winter, from October–November to May–June, the sea freezes, with the average January water temperatures of −1.9 °C in the north, between −1.3 and −1.7 °С in the centre, and between −0.5 and −0.7 °С in the bays.