Arctic Sea Ice Freeze Onsest

The product contains yearly maps of early freeze onset and freeze onset for the sea ice surface based on the improved PMW algorithm. The data were derived using brightness temperature observations from the Advanced Microwave Scanning Radiometer-Earth Observing System (AMSR-E) and the Advanced Microwave Scanning Radiometer 2 (AMSR2), Sea Ice Concentration (SIC) observations using the Enhanced NASA Team (NT2) algorithm, and sea ice age dataset. They are gridded on the NSIDC northern hemisphere polar stereographic grid at 12.5 km, with a time range of 2003 to 2021 (2011 and 2012 missing).