Remote sensing (ERTS) imagery has been used to map the distribution of leads in the sea ice over the Beaufort Sea during late February through early April in 1973, 1974, and 1975. A comparison of the bearings and speeds of ice movements obtained from ERTS-based maps with those of geostrophic winds calculated from average daily and weekly atmospheric pressure charts indicates that the ice drifts at about 1/100 of the speed of the geostrophic winds in a direction about 20 ¿ to the left of them. During early March 1973, before excessive ice breakup, the sea ice moved slowly, about 0.3 km/d, but during periods of rapid ice fracturing (March and April 1975) the sea ice moved at rates as high as 18.2 km/d.