Heat Budget and Decay of Clean and Sediment Laden Sea Ice Off the Northern Coast of Alaska

• Main Authors: Karoline Frey, Hajo Eicken, Don K. Perovich, Tom C. Grenfell, Bonnie Light, H. Shapiro, Aaron P. Stierle
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 2001
• Subjects: Arctic; albedo; Barrow; Sea ice; Alaska
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.522.1556; http://www2.gi.alaska.edu/~eicken/he_publ/FEPG01.pdf

The heat budget and decay of sea ice is strongly affected by the albedo of the surface in the melting season. Sea ice with a high sediment load, as often observed in Arctic coastal regions, has a much lower albedo than clean ice and snow, absorbing a higher fraction of incoming solar radiation. Here, we report measurements of warming and ablation of clean and sediment-laden ice near Barrow, Alaska. After melting of the snow cover, albedos of 0.41 and 0.29 were observed on clean and dirty sea ice. Higher extinction coefficients of sediment-laden sea ice result in absorption of 74 % of the incoming solar radiation within the uppermost 20 cm of the ice. Temperature records show that seasonal warming of the sediment-laden ice is delayed significantly by absorption of radiation in the uppermost layers. However, our observations also indicate that despite greater snow depths over sediment-laden ice, surface ablation rates were higher for dirty than for clean ice.