BUSINESS PROCESS

SD, SC, IN, SO

DESCRIPTION

The ice edge is the boundary at any given time between open water and sea ice.

EO INFORMATION OF INTEREST

Detection of the boundaries between water and sea ice.

MAIN PROCESS STEPS

Ice edge detection requires calibration using observations of an open ocean location and one which is thought to be 100% ice covered. SAR backscattering values of open water and sea ice are then used for classification. Empirical schemes employing different assumptions and corrections can be used to account for differing surface conditions.

INPUT DATA SOURCE

X-, C- and S-band SAR data; with strong wind, cross-polarized bands (as HV in Sentinel-1 SAR EW mode) support HH or VV bands (see limitations).

SPATIAL RESOLUTION AND COVERAGE

Spatial resolution 1-6km (2 to 5 times lower than the original SAR, as processing requires some sort of data aggregation) and same coverage of the original SAR.

ACCURACY / CONSTRAINS

The calibration of open water and sea ice backscatter thresholds is difficult in case of strong wind

LIMITATIONS

With weak wind, ice edge detection is easy using HH or VV bands. With strong wind, cross-polarized SAR bands, more noisy but less sensitive to rough sea, support the detection.

The interpretation of data can indeed be challenging, especially when handled by personnel without extensive experience in the field. 

TEMPORAL RESOLUTION

Similar to SIC. Various products with various frequency, including hourly, daily mean

FREQUENCY UPDATE

Any time a new SAR image is available

DELIVERY / OUTPUT FORMAT

NetCDF-3, NetCDF-4, geo-located raster and shape formats

ACCESSIBILITY

Same as for SIC products