The ice age product tracks how long ice survives within the Arctic. It provides not only a distinction between first-year and multiyear ice (i.e. the seasonal and perennial ice cover), but also details on the age of the multiyear ice pack. Using satellite and buoy data, individual sea ice parcels are tracked as they form, move on the Arctic Ocean surface, and disappear (through melt or transport out of the Arctic) at 12.5 km spatial resolution in Equal Area Scalable Earth () grid. This approach is based on ice motion vectors derived using a cross-correlation technique applied to sequential daily satellite images acquired by Scanning Multichannel Microwave Radiometer (SMMR), Special Sensor Microwave Imager (SSM/I) SSM/I Sounder (SSMIS), and Advanced Very High Resolution (AVHRR) sensors. Motion vectors are then blended via optimal interpolation with drifting-buoy vectors from the International Arctic Buoy Program (IABP).