Runaway W. Antarctic ice sheet collapse not ‘inevitable’: examine

The runaway collapse of the West Antarctic Ice Sheet—which might set off catastrophic sea stage rise—just isn’t “inevitable”, scientists mentioned Monday following analysis that tracked the area’s current response to local weather change.

As international temperatures rise, there may be mounting concern that warming may set off so-called tipping factors that set off irreversible melting of the world’s large ice sheets and finally carry oceans sufficient to drastically redraw the world map.

New analysis printed Monday suggests a posh interplay of things affecting the melting of the West Antarctic Ice Sheet, which is residence to the large and unstable Pine Island and Thwaites glaciers—nicknamed the “Doomsday glacier”—that collectively may increase international sea ranges by greater than three meters (10 ft).

Utilizing satellite tv for pc imagery in addition to ocean and local weather information between 2003 and 2015, a global crew of researchers discovered that whereas the West Antarctic Ice Sheet continued to retreat, the tempo of ice loss slowed throughout a susceptible area of the shoreline.

Their examine, printed within the journal Nature Communications, concluded that this slowdown was brought on by modifications in ocean temperatures that had been brought on by offshore winds, with pronounced variations within the impression relying on the area.

Researchers mentioned that this raises questions on how rising temperatures will have an effect on the Antarctic, with ocean and atmospheric situations taking part in a key function.

“That signifies that ice-sheet collapse just isn’t inevitable,” mentioned co-author Professor Eric Steig from the College of Washington in Seattle.

“It relies on how local weather modifications over the subsequent few many years, which we may affect in a constructive manner by decreasing greenhouse gasoline emissions.”

The researchers noticed that whereas in a single area, within the Bellingshausen Sea, the tempo of ice retreat accelerated after 2003, it slowed within the Amundsen Sea.

‘Blink of a watch’

They concluded that this was right down to modifications within the power and path of offshore floor winds, which may change the ocean currents and disturb the layer of chilly water round Antarctica and flush comparatively hotter water in the direction of the ice.

Each the North and South pole areas have warmed by roughly three levels Celsius in comparison with late Nineteenth-century ranges, practically 3 times the international common.

Scientists are more and more involved that the Pine Island and Thwaites glaciers have reached a “tipping level” that would see irreversible melting no matter cuts to greenhouse gasoline emissions.

Anders Levermann, a local weather scientist on the Potsdam Institute for Local weather Influence Analysis who was not linked to the newest examine, welcomed the strategy of bringing collectively a number of observations and information, though the examine interval was “the blink of a watch in ice phrases”.

“I feel we nonetheless should dwell and plan and do our sea stage projections and coastal planning with a speculation that the West Antarctic Ice Sheet is destabilized and we’ll get three and a half meters of sea stage rise simply from this space of the planet alone,” he mentioned, including nonetheless that this could occur “over centuries to millennia”.

The United Nation’s science advisory panel for local weather change, the IPCC, has forecast that oceans will rise as much as a meter by the top of the century, and much more after that.

Lots of of thousands and thousands of individuals dwell inside a number of meters of sea stage.

Whereas slicing planet-warming emissions is seen as the primary and most essential method to halt the melting of the West Antarctic ice sheet, scientists have additionally provide you with an array of hi-tech ideas for saving the gargantuan ice shelf and staving off.

Levermann has researched concepts together with utilizing snow cannons to pump trillions of tons of ice again on high of the frozen area.

Different ideas have included establishing Eiffel Tower-sized columns on the seabed to prop it up from under, and a 100m-tall, 100-kilometer-long berm to dam heat water flowing beneath.

© 2023 AFP