NASA MODIS Image of the Day: January 27, 2012 – Sea ice off the west coast of Kamchatka, eastern Russia
A silvery filigree of shining ice decorated the Sea of Okhotsk off the coast of western Kamchatka, Russia on January 22, 2012, when the Moderate Resolution Imaging Spectroradiometer (MODIS) aboard the Aqua satellite passed overhead and captured this this true-color still life of ice, sea, snow and clouds.
Off the western coast of Kamchatka, bitter winter cold sets in early, and the salty Sea of Okhotsk begins to freeze by late October.
Throughout the winter, the ice sheets thicken and expand. By March, 80 percent of the 611,000 square mile (1,583,000 km2) surface can be covered in free-floating sea ice. Sea ice is, very simply, frozen ocean water. In contrast to glaciers, ice sheets, ice shelves and icebergs, which all originate on land, sea ice forms, grows and melts in the ocean. The very first crystals to form are very tiny – typically 3 to 4 millimeters in diameter – and appear as fine, needle-like crystals. Because salt doesn’t freeze, these first crystals (known as “frazil”) are nearly pure fresh water. The salt becomes concentrated brine, and is slowly expelled into the nearby sea. Newly formed ice is often salty, because brine becomes caught in the crystalline frazil and in pockets on newly formed ice sheets. Over time, brine drips into the ocean, reducing the saltiness of the aging ice and increasing the salinity of the surrounding seawater.
