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ICEBERG BREAKS OFF THWAITES ICE TONGUE

March 18, 2002 — The National Ice Center confirms an iceberg broke off from the Thwaites Ice Tongue, a large sheet of glacial ice and snow extending from the Antarctic mainland into the southern Amundsen Sea. (Click NOAA satellite image for larger view of Iceberg B-22 taken March 11, 2002.)

This new iceberg, named B-22, is currently located at 74.56S/ 107.55W. Iceberg B-22, roughly 46NM long and 35NM wide, covers an area of approximately 2,120 square statute miles. Dr. Ted Scambos of the National Snow and Ice Data Center notified NIC of a large crack in the Thwaites Tongue, discovered by Jennifer Bohlander using NASA's MODIS data from February 10, 2001. The crack was found to have significantly widened in MODIS data from March 8, 2001. Analyst Judy Shaffier of the National Ice Center confirmed the calving of Iceberg B-22 using satellite images from the Defense Meteorological Satellite Program's Operational Line Scan Visible sensor and NOAA's Advanced Very High Resolution Radiometers (AVHRR) sensor.

Iceberg names are derived from the Antarctic quadrant in which they were originally sighted. The quadrants are divided counter-clockwise in the following manner:

A = 0-90W (Bellinghausen/Weddell Sea)
B = 90W-180 (Amundsen/Eastern Ross Sea)
C = 180-90E (Western Ross Sea/Wilkesland)
D = 90E-0 (Amery/Eastern Weddell Sea).

When an iceberg is first sighted, NIC documents its point of origin. The letter of the quadrant, along with a sequential number is assigned to the iceberg. For example, B-22 is sequentially the 22nd iceberg tracked by the NIC in Antarctica between 90W-180 (Quadrant B).

The National Ice Center is a tri-agency operational center represented by the United States Navy (Department of Defense); the National Oceanic and Atmospheric Administration (Department of Commerce); and the United States Coast Guard (Department of Transportation). The National Ice Center mission is to provide world-wide operational ice analyses for the armed forces of the United States and allied nations, U.S. government agencies, and the private sector.

Relevant Web Sites
Iceberg B-22 Image — Defense Meteorological Satellite Program's Operational Line Scan Visible sensor 776 x 1024

Iceberg B-22 Image — NOAA's AVHRR sensor 1500 x 1500

Defense Meteorological Satellite Program

Archived Satellite Images, Storm Animations and Special Events, Including Icebergs

Media Contact:
Patricia Viets, NOAA Satellite and Data Service, (301) 457-5005 or ENS Christi Montgomery, National Ice Center, (301) 457-5303, ext. 306

 

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