Incredible image of a giant 17-mile-long iceberg that just broke off Antarctica
The berg appears to have fractured from West Antarctica's Getz Ice Shelf and moved out into in the Amundsen Sea sometime in mid- to late-February 2015. Here's the before picture:
The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA's Terra and Aqua& satellites acquired these images spanning the calving event. The first image (left) shows the iceberg on February 16, when it was still attached to the ice shelf. By February 28 (middle), it appears to have separated somewhat. By March 5 (right), it is floating freely.Here's the after image:
B-34 is the 34th iceberg from the "B" quadrant of Antarctica (located between 90 degrees East and 180 degrees) to be tracked by the NIC. The new berg is still smaller, however, than the much older B-15T -a fragment of B-15 that initially broke off from the Ross Ice Shelf in March 2000.Large icebergs can have large-scale impacts on the Southern Ocean. For example, as the bergs melt, the addition of cold, fresh water to the saltwater ocean can affect ocean currents and circulation. Researchers have shown, however, that even more fresh water comes from the melting of smaller and much more numerous bergs.
If you have trouble seeing it in the larger image, here's a skitched version for you:
References- NASA Earth Observatory (2015, April 12) Iceberg B-15T Still Adrift.Accessed April 20, 2015.
- Tournadre, J. et al. (2015, March 26) Large icebergs characteristics from altimeter waveforms analysis. Journal of Geophysical Research: Oceans, 120 (3), 1954-1974.
- U.S. National Ice Center (2015, March 6) Iceberg B-34 Found in the Amundsen Sea. Accessed April 20, 2015.