Manhattan-Sized Iceberg Breaks Away From Antarctic Glacier
Satellite footage from NASA has captured the dramatic scene of a large piece of ice cracking and breaking off Antarctica’s Pine Island Glacier.
The massive, 2-mile-long iceberg — around the size of the island of Manhattan — is imaged by the Landsat 8 satellite ripping apart before it separates from the glacier, one of the largest within the West Antarctic Ice Sheet.
Pine Island Glacier
In the long history of icebergs breaking off, this recent occurrence captured occurring from Jan. 25 to 29 involves a relatively small chunk of ice. Two years earlier, an iceberg 10 times this size broke off in the same region, and scientists thought the recent break is an “aftershock” of that previous event that destabilized much of the area.
For years too, scientists have been watching a massive crack along the northernmost Antarctic ice shelf, discovered to have expanded by almost 11 miles or the size of Delaware. In December, the long-running rift in Larsen C ice shelf grew suddenly in by 11 miles. Early this month, data showed that the crack has crossed over 100 miles in length and has a mere 20 miles left to touch the other end of the ice shelf.
Once the crack engulfs the entire ice shelf, as Tech Times reported, the liberating ice chunk will be among the largest ever recorded.
But this does not mean smaller collapses such as this new one in Pine Island Glacier are without a consequence. This glacier makes up around 20 percent of the ice sheet’s total ice flow to the vast ocean and is the fastest melting in the continent, responsible for around a quarter of total ice loss.
The glacier’s last major calving or iceberg break took place in July 2015, when an iceberg spanning nearly 225 square meters separated from Pine Island.
“[This phenomenon] fits into the larger picture of basal crevasses in the center of the ice shelf being eroded by warm ocean water, causing the ice shelf to break from the inside out,” explained Ohio State University glaciologist Ian Howat in a statement.
Warming Oceans, Collapsing Ice Sheet
Since the 1990s, warming oceans have led to heightened melting at the surface and below the water. Subsurface melting is a dangerous affair, as it can destabilize large portions of ice and separate them from the rest of the glacier.
Subsurface melting will ultimately set off a chain reaction that will risk sending the entire region away to sea. The ice sheet that the glacier belongs to is considered highly unstable, with one massive collapse triggering further collapses elsewhere and predicted to increase sea levels by about 4 feet.
While this major collapse is unlikely to happen for decades, smaller events such as from last month have effects that matter. Loss of ice from the West Antarctic Ice Sheet, for instance, results in sea level rise of around 100th of an inch every year, a number that climbs with time. Sea level rises like that endanger hundreds of millions of both people and wildlife.
Just think of it this way: the loss of state-sized ice block exposes the remaining ice shelf to more climate-related attacks, speeding up its eventual collapse.