At about 43 degrees North latitude more than halfway to the equator Shikotan lies along the extreme southern edge of the range where winter sea ice forms in the Northern Hemisphere.
Although sea ice often forms around Shikotan, the extent varies widely from year to year, and even day to day.
The ice in this image, taken by NASA's Earth Observing-1 satellite, may have formed in a matter of several days, and it is prone to moving with currents.
North of the western end of Shikotan, eddies have shaped the ice into rough circles. The eddies may result from opposing windswinds from the north pushing the ice southward, and winds from the southwest pushing the ice toward the northeast.