NASA satellites provide frequent images of ocean color (SeaWiFS and MODIS) and sea surface temperature (MODIS) in the Arctic despite persistent cloud cover.
The extensive loss of sea ice in the Arctic Ocean over the last three decades has been documented using passive microwave imagery from the Scanning Multichannel Microwave Radiometer (SMMR) and more recently, the Special Sensor Microwave Imager (SSM/I).
High resolution sea ice cover data used for ship navigation are available from RADARSAT-2.