Integrating High Resolution AMSR-2 Imagery to Improve Large Scale Sea Ice Situational Awareness

The United States National Ice Center (USNIC) provides global to tactical scale ice and snow products, ice forecasting, and other environmental intelligence services for the United States government. The USNIC primarily relies upon remotely sensed satellite imagery to provide insight into current ice conditions. To fully meet its mission, high resolution imagery must be available to the USNIC analysts to communicate ice hazards to marine customers.

Passive microwave satellite data has a large footprint, allowing for near full polar daily coverage. While this would appear ideal to meet the USNIC’s global mission, passive microwave sources are inherently low resolution; additionally, the bands used by operational sensors were optimized to sense other environmental features, with sea ice only being detected as an obstruction signature. This historically has led to passive satellite imagery being used only for very large scale analyses, with no reliable detection of the marginal ice zone, coastal ice, and small-scale features.

The USNIC has recently begun receiving Advanced Microwave Scanning Radiometer 2 (AMSR2) data, which provides enhanced resolution and a band centered on detecting sea ice concentration. AMSR2 imagery is visually compared with existing operational passive sources to test whether the improvements can more accurately discern sea ice coverage along the ice edge and detect additional sea ice features. Additionally, this new imagery is compared to Synthetic Aperture Radar (SAR), which is an active radar imagery source that is known for its very high spatial resolution and precision in depicting differences in sea ice features, and visible imagery, which is known for its clear distinction between ice, open water, and land. Finally, AMSR2 is compared to the USNIC’s human analyzed products, primarily based on a mix of operational remote sensing, model data, and in-situ observations, to determine any error incurred when relying solely on high-resolution passive imagery for ice analysis.