Use of High-Resolution Polar-Orbiter Imagery and Evaluation of JPSS Ice Products in Sea Ice Analysis and Forecasting

The amount of detail required to track and analyze the concentrations and stage of sea ice is best provided by high-resolution polar-orbiting satellite imagery. The diminished temporal frequency of imagery, as compared to geostationary satellites, is balanced by the superior spatial resolution they provide. High-resolution imagery is capable of providing a plethora of information on sea ice. Concentration of ice is the most apparent data from the two dimensional top-down view, however, the appearance of ice over time can be used as a proxy for stage (thickness/age). The National Weather Service Alaska Sea Ice Program (ASIP) makes use of a multitude of satellite platforms and imagery to construct the daily analysis of ice concentration and stage from the Bering Sea through the Beaufort and Chukchi Seas as well as Cook Inlet. Visible and true color imagery from MODIS and VIIRS continue to serve well, sensing ice in cloud-free scenes. Infrared imagery becomes increasingly useful during the long winter as daylight is scarce while the Near Constant Contrast product (formerly known as the day/night band) allows for a consistent and comparable view with respect to visible imagery. Multi-channel RGB imagery combinations help discern ice from clouds and other land features. Synthetic aperture radar (SAR) and the Advanced Microwave Scanning Radiometer (AMSR-2) provide much needed microwave data coverage during prolonged cloudy periods as the signal is unaffected by clouds and precipitation. Despite the many and varying types of imagery available, there are still many days in which the imagery is insufficient for current meteorological conditions. The lack of data facilitates a need to collaborate with other agency partners for new analysis and forecasting techniques. In April of 2018 the Alaska Sea Ice Program participated in an evaluation of ice products from the Joint Polar Satellite System (JPSS). Products provided to the ASIP included analysis of Sea Ice Concentration, Ice Surface Temperature, Ice Thickness, and Blended Ice Motion. Examples intended for display will include the JPSS evaluation products, S-NPP Truecolor imagery, S-NPP Landcover, synthetic aperture radar, AMSR-2 Sea Ice Concentration, infrared and Near Constant Contrast.