Ice leads in the Beaufort Sea

By Scott Bachmeier • 20 December 2020

Suomi NPP VIIRS Infrared Window (11.45 µm) images [click to play animation]

Suomi NPP VIIRS Infrared Window (11.45 µm) images (above) showed widespread ice leads in the Beaufort Sea during the 18 December – 20 December 2020 period. Some existing leads increased in width and/or length as they migrated westward, while some new leads were seen to form as land-fast ice fractured off the coasts of Alaska and larger islands of the Canadian Arctic Archipelago.

Suomi NPP VIIRS Infrared images with plots of NAM12 model surface winds on 20 December (below) indicated that the ice lead motion was influenced by surface wind stress — which also played a role in the clockwise flow of the Beaufort Gyre (the primary influence of ice lead motion in that part of the Arctic Ocean).

Suomi NPP VIIRS Infrared Window (11.45 µm) images, with plots of NAM12 model surface winds [click to enlarge]

CIMSS Scientists are working on a Machine-learning Ice Lead detection method, as described here.  The toggle below compares the MODIS and VIIRS computations of Ice Leads on 18 December 2020. Leads in this toggle are white; greys are suspected leads, but the detection algorithm ultimately could not confirm their presence. At present, the algorithm is challenged when leads are moving, as in this example. Note that Banks Island, on the right edge of the animation above, is in the lower left corner in the toggle below.

MODIS and VIIRS-derived ice lead information, 18 December 2020 (Click to enlarge)

Categories: Arctic, Suomi NPP, VIIRS