Thread by @rdlarter

Great to see @GlacierThwaites research covered in national media, but a few points in this @guardian article need correction or further explanation.
1/n theguardian.com/world/2021/dec…

Firstly, “great cracks and fissures” have not “opened up both on top of and underneath the Thwaites glacier” itself, but on the floating ice shelf in front of it.
2/n

Secondly, the processes the triggered the ultimate break-up of the Larsen B Ice Shelf were different from those that are destabilising the Thwaites Eastern Ice Shelf. Larsen B break-up was triggered by extensive surface melt filling crevasses and causing hydrofracture.
3/n

Surface melt is a a very minor contributor to the changes at Thwaites, as even in summer temperatures are not warm enough to cause significant melting. In this case extensive basal melt of the ice shelf is thinning and destabilising it.
4/n

“Satellite studies show it is melting far faster than it did in the 1990s” is a massive understatement. In fact satellite data show the net rate of ice loss from Thwaites Glacier is more than 6 times what it was in the early 1990s.
5/n

The statement about annual rate of [global mean] sea-level rise “more than doubling from 1.4mm to 3.6mm between 2006 and 2015” is inaccurate and misleading. 1.4 mm/year is an estimate of the average rate thru the 20th century; 3.6 mm/yr is the mean rate from 2006 and 2015.
6/n

The suggestion "it is now considered possible it could happen rapidly" (i.e. an Antarctic glacier the size of Thwaites could be lost within years) is irresponsible scaremongering not supported by any scientist I know. The ice shelf may be, but not the entire glacier.
7/8

Coming back to basics, the West Antarctic Ice Sheet is not "a vast basin of ice on the Antarctic Peninsula". They are quite distinct geographically. Overall, as a subscriber, I'm disappointed by the inaccurate and misleading reporting in this article. Do better @guardian 8/8