- Iceberg fractured from Getz Ice Shelf and moved into the Amundsen Sea sometime in mid- to late-February
- Region is losing ice faster than anywhere on the continent and is the largest contributor to rise of sea levels
- Scientists are combining images such as this with noises from icebergs to detect how glaciers are melting
Once in a while, a colossal chunk of ice breaks free from Antarctica's majestic landscape and drifts out into the ocean.
In March, Nasa was able to capture this remarkable event from space during a process that was months in the making.
The monster iceberg, larger than Manhattan, was spotted breaking away from West Antarctica's Getz Ice Shelf by the U.S. National Ice Center (NIC)
Glaciers in the Amundsen Sea of west Antarctica are losing ice faster than anywhere else on the continent and are the largest contributors to the rise of sea levels.
Measuring 17 miles (27km) long, iceberg B-34 appears to have fractured and moved out into in the Amundsen Sea sometime in mid- to late-February 2015, Nasa said.
The Moderate Resolution Imaging Spectroradiometer (Modis) on Nasa's Terra and Aqua satellites took images spanning the calving event.
B-34 is the 34th iceberg from the 'B' quadrant of Antarctica 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.
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.
B-34 is the 34th iceberg from the 'B' quadrant of Antarctica to be tracked by the NIC. Glaciers in this region are losing ice faster than anywhere else on the continent and are the largest contributors to the rise
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.
Scientists are hoping to combine images such as this with noises recorded from icebergs to detect the different ways that glaciers lose ice into the oceans.
Earlier this year, the incredible sounds of an ice 'cracking' and crashing down into water as an iceberg were recorded by researchers..
The scientists used underwater microphones aboard buoys to record a variety of iceberg births at the Hans Glacier in Svalbard, Norway during three days in August 2013.
The recordings were then combined with time-lapse photos of the glacier during the same period.
By synchronising the sound recordings with the photographs, the researchers discovered that different types of ice loss are associated with distinct rumbles, snaps and splashes.
They are interested in this because the ice floating around Antarctica has thinned by nearly 20 percent, according to recent research.
This is depleting the bulwark that prevents the permanent collapse of glaciers covering the southern continent.
The study, based on satellite measurements between 1994 and 2012 by the European Space Agency, sheds new light on how Antarctic ice responds to climate change.
Ice barriers have an average thickness of between 400 to 500 meters (1,300 to 1,600 feet) and can extend hundreds of kilometers off the coast of Antarctica.
If the ice becomes too thin it would allow the permanent glaciers to slip into the ocean and start melting, sharply increasing the rise of ocean levels.
Researchers found that the total volume of Antarctic ice changed little between 1994 and 2003, but after that point melting markedly accelerated.
Ice in western Antarctica declined throughout the study period. A slight increase in ice thickness was observed in eastern Antarctica before 2003 when rapid melting began, leading to an 18 percent reduction of thickness compared to 1994.
'Eighteen percent over the course of 18 years is really a substantial change,' said Fernando Paolo, a researcher at the University of California, San Diego.
'Overall, we show not only the total ice shelf volume is decreasing, but we see an acceleration in the last decade.'
If the rate of thinning continues, the ice shelves could lose half of their volume over the next 200 years, the researchers calculated.
Source: dailymail.co.uk
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