ICESat-2 Measures Sea Ice Thickness
ICESat-2 will measure heights or elevations. In order to derive sea ice thickness from those measurements, it will compare the height of the ice with the height of the adjacent open water. The difference is height is the portion of the ice that is above the sea level, called freeboard. Because roughly 1/10 of the ice floe is above water we can calculate its thickness. Very often the only open water nearby is from cracks in the ice (leads) that open and close quickly as the ice drifts about in the polar oceans pushed by ocean currents and winds.
Please give credit for this item to:
NASA's Goddard Space Flight Center