Mapping and Characterization of Recurring Spring Leads and Landfast Ice in the Beaufort and Chukchi Seas

The Arctic sea-ice cover has undergone significant changes in the past two decades. These changes include a reduction in summer ice extent (with four consecutive record minima attained between 2001 and 2005) as well as substantial thinning of the ice pack. The western Arctic, i.e., the Chukchi and Beaufort Seas, has seen the largest anomalies in summer ice extent, as well as a substantial reduction in the amount of multiyear ice over the Beaufort and Chukchi shelves. The present project was aimed at mapping and documenting changes in the spatial and temporal distribution of spring lead systems and landfast ice extent off the coast of northern Alaska. In addition to providing baseline data against which to evaluate further changes, the work also examined present-day conditions in relation to earlier studies conducted in the 1970s as part of the Outer Continental Shelf Environmental Assessment Project and discussed the role of different forcing mechanisms in controlling spatial and temporal patterns of variability in lead distribution and landfast ice extent.

Hajo Eicken is professor of geophysics at the University of Alaska Fairbanks and the editor of "Field Techniques for Sea-Ice Research", also published by the University of Alaska Press.