Crack in Antarctic ice shelf could form giant iceberg

An iceberg larger than the state of Rhode Island could form in the Atlantic Ocean as a huge crack in an Antarctic ice shelf continues to grow at a fast pace.

The rift in the Larsen C ice shelf has grown from about 70 miles long in November to 110 miles long last month.  NASA says that IceBridge scientists measured the Larsen C fracture to be about 70 miles long, more than 300 feet wide and about a third of a mile deep.

Ice shelves in normal situations produce an iceberg every few decades. Scientists from the British Antarctic Survey say there is not enough information to know whether this is an effect of climate change or not, although they claim that there is good scientific evidence that climate change has caused thinning of the ice shelf.

Dr. Paul Holland from the Survey says, “Iceberg calving is a normal part of the glacier life cycle, and there is every chance that Larsen C will remain stable and this ice will regrow.  However, it is also possible that this iceberg calving will leave Larsen C in an unstable configuration.  If that happens, further iceberg calving could cause a retreat of Larsen C. We won’t be able to tell whether Larsen C is unstable until the iceberg has calved and we are able to understand the behavior of the remaining ice."

The largest iceberg known have all calved from an ice shelf was in 1956 when an iceberg larger than Belgium was spotted a US Navy icebreaker. However, since there were no satellites in orbit at that time, its exact size was not verified.