January 31, 2021 - Sea Ice off Brunt Ice Shelf

    Follow @NASA_MODIS

   Sea Ice off Brunt Ice Shelf
    Tweet
    Share

   On January 25, 2021, the Moderate Resolution Imaging Spectroradiometer
   (MODIS) on board NASA’s Aqua satellite acquired a true-color image of
   copious sea ice floating in the Weddell Sea near the Brunt Ice Shelf.

   Sea ice is frozen seawater that floats on the ocean surface. Frigid
   Antarctic winters cause widespread freeze up of surface water near the
   continent. Much of winter’s ice is “fast ice”—ice that stays fast in
   place because it is attached to shore. As daylight lengthens and
   temperatures rise through spring and summer, Antarctic sea ice
   inevitably begins to melt. As melting occurs, fast ice begins to break
   up into chunks. Many of these chunks can be classified as “bergy bits”
   or “growlers”, but sea ice can be even smaller especially as melting
   advances. According to that National Oceanic and Atmospheric
   Administration (NOAA), a bergy bit is a medium to large fragment of ice
   with a height generally greater than three feet but less than 16 feet
   above sea level, with an area of about 1,076-3,299 square feet.
   Growlers are small fragments of ice and are roughly the size of a truck
   or grand piano. Icebergs are larger than bergy bits. Sea ice
   maximum—the largest amount of sea ice—in the Antarctic usually occurs
   in September while the minimum usually occurs in February.

   While sea ice captures attention in this image, expectations of a
   calving event have turned the eyes of the world the Brunt Ice Shelf
   itself. A substantial crack first appeared on the shelf in October 2016
   and has continued to extend eastward. In January 2019, a rift that had
   been stable for about 35 years began to rapidly advance, moving toward
   the 2016 crack. By February 2019, scientists were waiting for the
   “imminent” calving of an iceberg that would likely measure about twice
   the size of New York City. While the cracking and rifting continues,
   the Brunt Ice Shelf has continued to hold together—so far. Whether it
   can withstand the warmth of another Antarctic summer or not is anyone’s
   guess.

   On January 12, 2021, NASA’s Earth Observatory published an informative
   story on the Brunt Ice Shelf and the impending calving event. To enjoy
   this story, titled “Brunt Breaking Up with Antarctica this Year?, click
    here .

   Image Facts
   Satellite:  Aqua
   Date Acquired: 1/25/2021
   Resolutions:  1km (86.1 KB),  500m (327.7 KB),  250m (1 MB)
   Bands Used: 1,4,3
   Image Credit: MODIS Land Rapid Response Team, NASA GSFC



https://modis.gsfc.nasa.gov/gallery/individual.php?db_date=2021-01-31
 
