Global warming may have pushed Greenland’s ice sheets past a tipping point, with the island having lost ice from its glaciers faster than snowfall could replenish them over the past two decades, according to a new study. Although this trend is expected to worsen as global temperatures increase, the researchers
A recently-published study from NASA has revealed that glaciers in West Antarctica’s Marguerite Bay have increased their flow rate, speeding up by up to 25 percent, an event that has accelerated ice loss in the region from 2 to 3 meters (7 to 10 feet) per year to 10 meters (33 feet). Prior to 2008, the flow rates of the four affected glaciers had been stable for two decades, but a major calving event in 1989 left the bay with little to no ice shelf, leaving them with only grounded ice on dry land — a precarious position for its potential to affect sea level rise.
A Delaware-sized portion of Antarctica’s forth-largest ice shelf calved off, sometime between July 10th and 12th, following the rapid propagation of a 127 kilometer (79 mile) long crack running through the sheet. The resulting iceberg is over 200 meters (656 feet) thick, and covers roughly 6,000 square kilometers (Delaware itself is only 5,130 square kilometers (1,982 square miles). This will likely place it as the third-largest known iceberg in modern history.
Large-scale glacial melt is one of the realities that is being addressed by researchers in regards to global warming, as these systems of ice are the chief source of water contributing to sea level rise as global temperatures increase. There is a great deal of concern over the ice sheets covering Greenland, melting due to the nature of ocean currents in the region, and the ice shelves in West Antarctica, vulnerable from melt caused by warm water from below, as well as increasingly warm air from above. In contrast, the much more massive ice sheet that covers East Antarctica has historically been considered stable, and has been recorded as gaining ice in recent years, as opposed to the losses seen by Greenland and West Antarctica.