The polynya I saw forming in early February is still clear, and very large in the Southern Weddell Sea. At the moment it is more than than 80,000 km2, although there is clearly a lot of young sea ice covering a large part of the polynya.
In my original post I said this was likely formed by winds from the Ronne Ice Shelf.
Well Dr Stef Lhermitte (Delft) has put together the most amazing movie showing the development of the polynya over January and February. It shows satellite sea ice data with winds from the ECMWF overlain.
You can clearly see the winds pushing the sea ice away from the ice shelf as time progresses.
It is just as @StefLhermitte said in his tweet yesterday: