Royal Navy survey vessel discovers another retreating Antarctic glacier
Sailors from the Royal Navy’s HMS polar research vessel Protective discovered a huge Antarctic glacier that is disappearing at an alarming rate.
The Sunshine Glacier has shrunk by a seventh in 20 years – an area the size of more than 130 football fields has melted. Just two decades earlier, where HMS Protective The small survey boat visited had been a towering wall of ice some 700 meters from the current terminus of the glacier.
The icebreaker and survey vessel recorded the worrying changes as it visited Coronation Island – a 45 kilometer long forbidden piece of rock and ice and the largest island in the Orkney Range of the South.
It was the first visit to the inhospitable and uninhabited island – with names such as Penguin Point and Despair Rocks – since 2017, and provided a rare opportunity for the survey vessel and motorboat. James Caird IV conduct survey activities in the ice-filled glacial bays of the archipelago.
The ship was asked to update existing maps of the waters around the island, including Iceberg Bay, where the Sunshine Glacier empties into the ocean. Here the mass of ice and rock – continuously moving at about 25 centimeters per day – completes its five kilometer journey. Huge chunks of blue and white ice the size of a house or more are breaking off and floating in the bay.
Protective and its launch James Caird IV – stuffed with high-tech sensors but able to use them in shallower, tighter waters his mothership cannot access – set out to survey the two-mile-wide bay, eclipsed in a primeval world of rocks and seracs, huge towers of ice.
“A quick check of the graph showed James Caird IV surveying lines north of the ice terminus as plotted in 2001 – but the boat was definitely still at sea and had not yet reached the new position of the ice front,” said Lt. Michael Wafer. “The actual position of the ice front and towering seracs (ice pillars) was nearly 700 meters north of the position mapped in 2001. This is most likely just more demonstrable evidence of climate change in action.
Dr Robert Larter, a marine geophysicist at the British Antarctic Survey who has been involved in similar studies of glaciers around the Antarctic Peninsula, said Protective the findings mirrored the findings of his organization: 87% of the region’s glaciers have retreated in the past 75 years or so.
“A similar rapid retreat is occurring at many glaciers along the Antarctic Peninsula due to rapid regional warming – three times the global average rate – during the second half of the 20th century,” he explained. “Along much of the western side of the peninsula, glacial retreat is also driven by the incursion onto the continental shelf of warm water from the deep ocean. Antarctica’s ice loss represents currently around 10% of global sea level rise – and the rate of ice loss has been steadily increasing over the past 30 years.
Protective is the Royal Navy’s only icebreaker, dedicated to summering in the Southern Hemisphere in and around the Antarctic Peninsula, supporting UK and international scientists’ understanding of the frozen continent, its unique environment and wildlife , as well as updating existing marine charts of the waters to the latest standards.
When the weather prohibits working in the polar regions, Protective shifts its activities to warmer water; last fall she worked extensively off St Helena and Ascension Island, two British Overseas Territories in the middle of the Atlantic.
HMS Protector delivers supplies to the BAS outpost on Rothera (Royal Navy)
The icebreaker also provides supplies and personnel to numerous BAS bases and research stations, from South Georgia on the Antarctic periphery to the main research station at Rothera.
She made her last visit to Rothera in the last days of the austral summer, unloading stores and goods before the onset of winter when weather conditions prevent ships from passing. Visits to Rothera over the past two years have been few, making this Covid-secure stay even more critical to the year-round work of the station team and the scientists there.
This article appears courtesy of Royal Navy News and can be found in its original form here.