The Thwaites Ice Front in the Vulnerable Sector of West Antarctica is very large (70 miles wide where it meets the ocean) and in its entirety the size of Florida. The glacier is the most feared because it is rapidly breaking down and threatening coastal cities around the world. The bottle cap for all of West Antarctica contains ten feet of sea level rise. The collapse of the marine extension will not add to sea level rise as it floats already. When it collapses, the plug pops and land ice is free to slide into the Weddel Sea and Amundsen Sea, raising sea levels.
All damage to Thwaites stability occurs under the ice. The upwelling of warm ocean water softens and erodes the soft white belly of the glacier. The upwelling also lifts the ice, where warmer water can flow to the crests and past the grounding line, promoting ice breakdown with faster, more crashing and fracturing flow with the threat of collapse. Water can do this because the ice is no longer anchored to bedrock.
The ocean in front of the glacier is still quite cold, around 34-36 degrees Fahrenheit. It’s above freezing, and if you think about your ice-filled afternoon cocktail, it’s similar to the temperature of ocean water eating away at the glacier. As you sip your cocktail, you observe that the ice is melting, which is precisely what is happening under the immense marine extension of the Thwaites Glacier. The glacier alone holds two feet of sea level elevation.
Geophysicists were able to map the seabed front of the glacier. Like you and me, we have a history, just like Thwaites.
A recent study from the University of South Florida:
At some point in the past 200 years, over a span of less than six months, the glacier front lost contact with a seabed ridge and retreated at a rate of more than 2.1 kilometers per year (1.3 miles per year) – twice the rate documented using satellites between 2011 and 2019.
“Our results suggest that very rapid retreat pulses have occurred at Thwaites Glacier over the past two centuries, and possibly as recently as the mid-20th century,” Graham said.
“Thwaites is really holding 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 to the beyond a shallow ridge in its bed,” the marine geophysicist said. and study co-author Robert Larter of the British Antarctic Survey.
The tongue of Thwaites is fifty miles wide. You can make a distinction on the tongue based on its stability and whether it is anchored to a ridge. Although in peril, the western part of the language is still relatively stable. The eastern part is losing chunks of ice like there’s no tomorrow, and the eastern part also contains the majority of the land’s ice. Sooner than later for chaos, in my opinion.
For twenty-two years, a large iceberg named Iceberg B22a broke away from the Thwaites Tongue in 2001 and stuck in front, protecting the remaining open ocean ice. The iceberg was fifty-three miles long and forty miles wide. It is also subject to warming waters and the iceberg has thinned enough to be freed from the mount it was stuck on in September 2022. This means a brutal assault on Thwaites from the ocean will occur. A flotilla of icebergs calving from the front is expected following the iceberg emerging from the Amundsen Sea and entering the Weddel. If you didn’t know, West Antarctica passed the tipping point many years ago.
#Nails #clinging #Thwaites #Glacier #peeling