Penguins are spared after splitting the mammoth iceberg into smaller pieces

Then there was the question of the penguins.

Ecologists feared that the island’s huge colonies of king and gentoo penguins would have to make long detours to reach their usual hunting grounds, with potentially dire consequences for chicks waiting ashore.

Almost wrong

A huge iceberg nearly hit the island of South Georgia and its fragile habitat before breaking up in the strong currents of the South Atlantic Ocean.

SOUTH GEORGIA ISLAND (UK)

SOUTH GEORGIA ISLAND (UK)

SOUTH GEORGIA ISLAND (UK)

A huge iceberg nearly hit the island of South Georgia and its fragile habitat before breaking up in the strong currents of the South Atlantic Ocean.

SOUTH GEORGIA ISLAND (UK)

Source: British Antarctic Survey, derived from Copernicus Sentinel-1 satellite images

Instead, more than three years after the calving of Antarctica’s Larsen C Ice Shelf, some 930 miles to the south, warmer waters and the torque of the currents have broken the behemoth into a dozen pieces, now known as A68b, A68c , and so on under the US National Ice Center naming system. They now seem to be drifting north where they could prove to be a bigger problem for humans.

“If it disintegrates, thousands of smaller icebergs have the potential to block shipping lanes in the area, especially if they spread,” said Andrew Fleming, chief of remote sensing at the British Antarctic Survey, which tracks the A68’s journey north. images provided by the European Space Agency and flyovers by the British Royal Air Force.

The main portion, still called A68a, is 330 square miles, larger than New York City, with several chunks nearly as big. The break-up of A68a means that the largest iceberg is now A23a, which broke off from Antarctica in 1986 but has remained on the sea floor.

A team from the British Antarctic Survey is on its way from the Falkland Islands to assess the impact of the icebergs on the marine ecology of the area and understand what can be expected if the Antarctic Ice Shelf crumbles more giant mountains as global temperatures rise.

“Everyone is pulling out all the stops to make this happen,” said oceanographer and team leader Povl Abrahamsen, aboard the RRS James Cook, arriving near the icebergs in mid-February.

Navigating through a bunch of huge icebergs can be a tricky endeavor, however. In addition to the mountains themselves – especially the parts below the surface – there are waterfalls of melting ice and the prospect of more chunks breaking off, creating big waves. To reduce the risk, the mission will include two underwater robotic gliders to collect samples that will give the team a better idea of ​​what kind of impact such a large mass of icebergs has on ocean conditions off South Georgia, one of the most biologically rich places. on the planet and one of the world’s largest marine protected areas.

The main concern is how the melting mountains could disrupt the ocean’s food chain. An influx of cold fresh water could kill microscopic marine organisms called phytoplankton, starve the krill that feeds on it, and deplete populations of fish, seals, penguins and whales.

The area is so abundant with marine life that Norwegian whalers established a whaling station in South Georgia in the early 20th century, which has since been abandoned.

Today there are no permanent residents on the island, just a rotating team of ecologists and other scientists who monitor fish stocks and other wildlife, including albatrosses and seals.

However, the island is increasingly important as a base for tracking the number of icebergs breaking off the Antarctic ice sheet and drifting north into warmer waters.

While icebergs have always chipped, or calved, off the ice sheet, the concern is that a warming climate will flatten it like a melting snow cone, propelling more ice to the continent’s edge, where it will eventually break off.

In a study published earlier this week, two geophysicists from the University of Copenhagen in Denmark warned that climate change could cause oceans to rise faster than initially feared, increasing the risk of flooding for densely populated coastal areas.

Aslak Grinsted and Jens Hesselbjerg Christensen searched for data dating back several centuries and found that ocean levels could rise by more than a meter if Earth’s temperature were to rise by 2 degrees Celsius, more than the current projections assumed by the Intergovernmental Panel of the United Nations on climate change, and by half a meter if the temperature rises only half a degree Celsius.

Write to James Hookway at [email protected]