Antarctic Science

Papers—Earth Science and Glaciology

The calving and drift of iceberg B-9 in the Ross Sea, Antarctica

Harry (J.R.) Keys a1p1, S.S. Jacobs a2 and Don Barnett a3
a1 Science and Research Division, Department of Conservation, P.O. Box 10–420, Wellington, New Zealand
a2 Lamont-Doherty Geological Observatory, Columbia University, Palisades, NY 10964, USA
a3 Navy/NOAA Joint Ice Center, 4301 Suitland Road, Washington, DC 20395–5180, USA

Article author query
keys h   [PubMed][Google Scholar] 
jacobs s   [PubMed][Google Scholar] 
barnett d   [PubMed][Google Scholar] 


Major rifts is the Ross Ice Shelf controlled the October 1987 calving of the 154 × 35 km “B-9” iceberg, one of the longest on record. The 2000 km, 22 month drift of this iceberg and the quite different tracks of smaller bergs that calved with it have extended our understanding of the ocean circulation in the Ross Sea. B-9 initially moved north-west for seven months until deflected southward by a subsurface current which caused it to collide with the ice shelf in August 1988. It then completed a 100 km-radius gyre on the east-central shelf before resuming its north-westerly drift. Based upon weekly locations, derived from NOAA-10 and DMSP satellite and more frequent ARGOS data buoy positions, B-9 moved at an average speed of 2.4 km day−1 over the continental shelf. It was not grounded there at any time, but cast a large shadow of open water or reduced ice thickness during the austral winters. B-9 was captured by the continental slope current in May 1989, and attained a maximum velocity of 13 km day−1 before breaking into three pieces north of Cape Adare in early August 1989.

(Received December 12 1989)
(Accepted June 11 1990)

Key Words: Calving icebergs; ocean currents; satellite tracking.

p1 Dept of Conservation, Private Bag, Turangi, New Zealand