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.
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NASA ID
GSFC_20180822_ICESat2_m13049_SEAICE
Date Created
August 22, 2018
Center
GSFC
Media Type
video
Location
Goddard Space Flight Center
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