Science

The nails that stick to the Thwaites Glacier seem to be peeling off.

The nails that stick to the Thwaites Glacier seem to be peeling off.

On a research cruise in Antarctica, WHO postdoctoral scientist Peter Kimball helped use the Jaguar robotic vehicle to map the bottom of the ice. But the trip was memorable for more than just its success in a tough environment. We were stuck in a heavy pack of ice for almost two weeks, Kimball recalls. We could not see any open water around the ship, and the ice was too thick for the ship to break up. While we were trapped, this magnificent minke whale broke a few centimeters of ice with a small lead and was breathing through the hole, right near our boat, for a whole day.

The front of the Thwaites Glacier in the vulnerable sector of West Antarctica is very wide (70 miles wide where it meets the ocean) and, in its entirety, is the size of Florida. The glacier is the most feared as it is rapidly receding and threatening coastal cities around the world. The bottle cork for all of West Antarctica is ten feet of sea level rise. Sinking seafloor will not increase sea level rise as it is already floating. When it collapses, the cork bursts and the land ice is free to slide into the Weddel Sea and the Amundsen Sea, raising sea levels.

All damage to Thwaites’ stability occurs under the ice. Rising warm ocean water softens and erodes the soft white underbelly of the glacier. Upwelling also lifts the ice, where warmer waters can flow towards the ridges and beyond the ground line, promoting ice decay with faster flow, more breaking and fracturing with the threat of collapse . Water can do this because the ice is no longer anchored to the rock.

The ocean at the front of the glacier is still quite cold, about 34-36 degrees Fahrenheit. That’s above freezing, and if you think about your afternoon cocktail full of ice, that’s similar to the temperature of the ocean water you eat on the glacier. Sipping your cocktail, you notice that the ice is melting, which is precisely what is happening at the bottom of the massive marine expanse of Thwaites Glacier. The glacier itself has two feet of sea level rise.

Geophysicists were able to map the seafloor front of the glacier. Like you and me, we have a story, and Thwaites too.

A 3D view of multibeam bathymetry (shape of the seafloor) colored by depth, collected by Rán across a seafloor ridge, just in front of the Thwaites Ice Shelf.
A 3D view of multibeam bathymetry (seafloor shape) colored by depth, collected by Rán across a seafloor ridge just off the Thwaites Ice Shelf

A recent study from the University of South Florida:

At some point in the last 200 years, for a duration of less than six months, the glacier front lost contact with a seafloor ridge and retreated at a rate of more than 2.1 kilometers per year (1 .3 miles per year), twice the rate documented by satellites between 2011 and 2019.

“Our results suggest that pulses of very rapid retreat have occurred on Thwaites Glacier in the last two centuries, and possibly as recently as the mid-20th century,” Graham said.

“Thwaites is really holding on today by its fingernails, and we should expect to see big changes on small time scales in the future, even from year to year, once the glacier retreats beyond a shallow ridge in its bed,” said the marine geophysicist. and study co-author Robert Larter of the British Antarctic Survey.

Thwaites tongue is fifty miles wide. A distinction can be made about the tongue according to its stability and whether it is anchored to a ridge. While endangered, the western part of the language is still relatively stable. The eastern part is shedding chunks of ice like there’s no tomorrow, and the eastern part also contains the most land ice. Sooner than early for mayhem, in my estimation.

For twenty-two years, a major iceberg called Iceberg B22a it broke off the Thwaites’ tongue in 2001 and stuck to their forehead, protecting the remaining ice from the open ocean. The iceberg was fifty-three miles long and forty miles wide. It is also subject to warming waters, and the berg thinned enough to break free from the mountain it was attached to. September 2022. This means that there will be a brutal assault on Thwaites from the ocean. A flotilla of icebergs is expected to leave the front after the iceberg that leaves the Amundsen Sea and enters the Weddel. If you didn’t know, West Antarctica passed the tipping point many years ago.





#nails #stick #Thwaites #Glacier #peeling

Related Articles

Leave a Reply

Your email address will not be published. Required fields are marked *

Back to top button