HR: 0800h
AN: C41B-0197 [Abstracts]
TI: The 2003-04 Sea Ice Season at Barrow as Seen by Land-Based Radar
AU: * Robson, K L
EM: robson@simpson.edu
AF: Simpson College, 701 N C Street
Unit 3790, Indianola, IA 50125
United States
AU: Mahoney, A
EM: mahoney@gi.alaska.edu
AF: Geophysical Institute, 903 Koyukuk Drive
University of Alaska Fairbanks, Fairbanks, AK 99775
United States
AU: Eicken, H
EM: eicken@gi.alaska.edu
AF: Geophysical Institute, 903 Koyukuk Drive
University of Alaska Fairbanks, Fairbanks, AK 99775
United States
AB:
The objective was to determine the position of the landfast sea ice edge and its morphology throughout the 2003-04 sea ice
season near Barrow using a land-based 10 kW, X-band (3 cm) marine radar mounted on a building near the beach at the Ukpeagvik
Inupiat Corporation Naval Artcic Research Laboratory (UIC-NARL). This data would then be used to help understand how
landfast ice attaches to coast and what causes it to breakaway. An improved understanding together with real-time data
available on the internet will provide more information for the safety of whalers, Native people, and the development of
nearshore operations.
X-band radar does not discriminate well between level ice and open water, since both areas are characterized by very low
back-scatter, but it detects ice floes and rough ice that contain surfaces facing towards the radar. It is very effective at
monitoring nearshore sea ice motion in a time series of data. Landfast ice can change very rapidly with break-offs and ice
shoves occurring in a matter of hours and nearshore pack ice motion can reverse several times in one day. We were able to
monitor these changes by the animation of radar images spaced at five-minute intervals.
A very similar land-based radar was installed on the beach approximately 500m further towards Barrow between 1973 and 1979
(Shapiro and Metzner, 1991). In a comparison with this earlier study, the 2003-04 season was noted to be much more dynamic
and there was less observed pack ice. In conjunction with field measurements, it was also observed that a stable fast ice
edge does not necessarily correlate with a grounded ridge, contrary to the World Meteorological Organization's definition of
fast ice.
DE: 9315 Arctic region
DE: 4540 Ice mechanics and air/sea/ice exchange processes
DE: 1635 Oceans (4203)
DE: 1640 Remote sensing
SC: Cryosphere [C]
MN: 2004 AGU Fall Meeting