An iceberg twice the size of New York City looks like it is about to to detach itself from the Brunt Ice Shelf in Antarctica. In the last few months, two enormous cracks from the north and south are close to joining. In their path they threaten the future of Halley research station.
Calvings, when icebergs are formed by a glacier, are not unusual in Antarctica. However they generally appear on a smaller scale. This does not appear to be the case on the Brunt Ice Shelf situated in the Coats Land region which is 120 metres thick and borders the Waddell Sea. There are two enormous cracks in the ice. The Halloween Crack opens from above while the second crack called Chasm 1 is opening increasingly quickly from below (about 4 km /year). If these two cracks join a gigantic iceberg could soon break off and drift away.
Twice the size of New York City
“The near future of the Brunt Ice Shelf will probably depend on the fusion of the existing cracks,” stated Joe MacGregor, a glaciologist from the Goddard Space Flight Centre, NASA. “If these cracks fuse, it is possible that the iceberg will be knocked off balance.” If the ice shelf calves, it will be quite simply the biggest iceberg that has detached itself from the Brunt Ice Shelf in 100 years. If this iceberg breaks away it will have a surface area of about 1700 km 2 which is twice the size of New York City depending on where the cracks meet, highlight the researchers.
Halley Station threatened
As a result of these cracks the Ice Shelf could become unstable which could threaten the Halley Antarctic base which is a permanent research station on the Brunt Barrier. The laboratory was installed in 1956 by British researchers with aim of studying the Earth’s atmosphere. It is thanks to this station that researchers became aware in 1985 that there was a hole in the ozone layer.
The research centre has been moved twice in the last three years over security issues. For the time being, NASA have stated that theydon’t know how the remaining ice sheet will be affected by the calving process which means there could be new uncertainty for the scientific centre.