Validation and production of RADARSAT-1 derived ice-motion maps in the North Water (NOW) Polynya, January-December 1998

Monitoring ice motion may provide insight into the atmospheric and oceanic forces acting on ice motion and thus the mechanisms that contribute to poly nya dynamics. A study of ice kinematics in the North Water ( NOW) region wa s performed using time sequential and spatially overlapping RADARSAT-1 Scan SAR Wide images ( January to December 1998) processed by the Canadian Ice S ervice ( CIS) Ice Tracking Algorithm ( Tracker). The objectives of this res earch were to: 1) validate the NOW region ice motions derived using Tracker ; 2) create monthly image-maps that present ice speeds and directions over the NOW region for an entire year ( January to December 1998); 3) compare t hese results to previous ice motion studies done in the NOW region; and 4) develop initial insights into relations between derived ice motion and late nt and sensible heat mechanisms in the NOW Polynya. Tracker ice motions were validated using in situ ice beacons deployed betwe en April and November 1998. Tracker magnitude and direction coefficients of determination (R-2) were 0.93 and 0.79 respectively, with standard errors of estimate of 3.6 km in magnitude and 38.8 degrees in direction. The month ly ice motion maps describe the annual evolution of the polynya quite accur ately and compare well to other studies. High levels of ice export are foun d which supports the theory that winds or ocean currents continually remove ice from the polynya as it forms. A northward import of ice into the polyn ya along the Greenland coast shows the recycling of ice into the polynya. E vidence of oceanic (sensible) heat contributing to the open water of the po lynya was not evident using the Tracker ice motion methods.