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Iceberg C-39 Has Calved From Scott Glacier area of the Shackleton Ice Shelf
by Christopher Readinger
27 April 2022
SUITLAND, Md. --
SUITLAND, MD — The U.S. National Ice Center (USNIC) has confirmed that iceberg C-39 (figure 1, below) has calved from the Scott Glacier area of the Shackleton Ice Shelf in the Wilkes Land Region of Antarctica. As of April 22, C-39 was centered at 65° 40' South and 99° 44' East and measured 15 nautical miles on its longest axis and 8 nautical miles on its widest axis.
The new iceberg was first spotted by Jan Lieser from the Australian Bureau of Meteorology, and confirmed by USNIC Analyst Christopher Readinger using the Sentinel-1A image below.
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 (Bellingshausen/Weddell Sea)
B = 90W-180 (Amundsen/Eastern Ross Sea)
C = 180-90E (Western Ross Sea/Wilkesland)
D = 90E-0 (Amery/Eastern Weddell Sea)
When first sighted, an iceberg’s point of origin is documented by USNIC. The letter of the quadrant, along with a sequential number, is assigned to the iceberg. For example, C-19 is sequentially the 19th iceberg tracked by USNIC in Antarctica between 180-90E (Quadrant C). Icebergs with letter suffixes have calved from already named icebergs, where the letters are added in sequential order. For example, C-19D is the 4th iceberg to calve off the original C-19 iceberg.
Iceberg positions are analyzed weekly and are available on the USNIC webpage at:
The U.S. National Ice Center is a multi-agency center operated by the Navy, NOAA, and Coast Guard and provides global to tactical scale ice and snow products, ice forecasting, and related environmental intelligence services for the United States government.
The U.S. National/Naval Ice Center is a subordinate command of U.S. Naval Meteorology and Oceanography Command that directs and oversees more than 2,500 globally-distributed military and civilian personnel who collect, process and exploit environmental information to assist Fleet and Joint Commanders in all warfare areas to make better decisions, based on assured environmental information, faster than the adversary.
US National Ice Center
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