Thwaites glacier is in West Antarctica where all the heating in Antarctica is going on. It has a frontage of 90Km and drains a much bigger area than the Larsen ice sheets on the Antarctic Peninsula. And it is in trouble.
Quote:The trouble with Thwaites, which is one of the largest glaciers on the planet, is that it's also what scientists call "a threshold system." That means instead of melting slowly like an ice cube on a summer day, it is more like a house of cards: It's stable until it is pushed too far, then it collapses. When a chunk of ice the size of Pennsylvania falls apart, that's a big problem. It won't happen overnight, but if we don't slow the warming of the planet, it could happen within decades. And its loss will destabilize the rest of the West Antarctic ice, and that will go too. Seas will rise about 10 feet in many parts of the world; in New York and Boston, because of the way gravity pushes water around the planet, the waters will rise even higher, as much as 13 feet. "West Antarctica could do to the coastlines of the world what Hurricane Sandy did in a few hours to New York City," explains Richard Alley, a geologist at Penn State University and arguably the most respected ice scientist in the world. "Except when the water comes in, it doesn't go away in a few hours – it stays."
http://www.rollingstone.com/politics/features/the-doomsday-glacier-w481260That is not a hugely scientific publication but the above is entirely in accord with the views of climatologists and glaciologists quoted in articles on the Larsen C breakoff.
Maybe we are being too pessimistic? NASA thinks so:
Quote:The melt rate of West Antarctica's Thwaites Glacier is an important concern, because this glacier alone is currently responsible for about 1 percent of global sea level rise. A new NASA study finds that Thwaites' ice loss will continue, but not quite as rapidly as previous studies have estimated.
The new study, published in the journal Geophysical Research Letters, finds that numerical models used in previous studies have overestimated how rapidly ocean water is able to melt the glacier from below, leading them to overestimate the glacier's total ice loss over the next 50 years by about 7 percent.
Thwaites Glacier covers an area nearly as large as the state of Washington (70,000 square miles, or 182,000 square kilometers). Satellite measurements show that its rate of ice loss has doubled since the 1990s. The glacier has the potential to add several inches to global sea levels.
The new study is led by Helene Seroussi, a scientist at NASA's Jet Propulsion Laboratory in Pasadena, California. It is the first to combine two computer models, one of the Antarctic ice sheet and one of the Southern Ocean, in such a way that the models interact and evolve together throughout an experiment—creating what scientists call a coupled model.
Previous modeling studies of the glacier used only an ice sheet model, with the effects of the ocean specified beforehand and unchanging.
Seroussi and colleagues at JPL and the University of California at Irvine (UCI) used an ocean model developed at the Massachusetts Institute of Technology in Cambridge with an ice sheet model developed at JPL and UCI. They used data from NASA's Operation Icebridge and other airborne and satellite observations, both to set up the numerical model simulations and to check how well the models reproduced observed changes.
https://phys.org/news/2017-06-thwaites-glacier-ice-loss-quickly.html#jCp
That is what you get when you increase the CO2 in the atmosphere by 46%.