There has been lots of talk about volcanoes beneath the West Antarctic peninsular and now we seem to have proof – see www.jpl.nasa.gov/news/news.php?release=2017-291 … as a NASA study adds evidence that a geothermal source (a mantle plume) lies deep under Antartica's Marie Byrd Land. This may thus be able to explain why the West Antarctic peninsular has been unstable recently, in direct contrast to the large block of Antarctica which has stubbornly remained very cold and surrounded by lots of sea ice. Apparently, melting under the ice sheet has created lakes and rivers which is the origin of the ice melt. The stability of the ice sheet is related to how much water lubricates it from below, allowing glaciers to slide freely. The press release comes from NASA but you can also read the story at https://wattsupwiththat.com/2017/11/07/nasa-volcanic-magma-plume-under-a… … which has the magic word 'may' – and this may imply other factors are also involved (such as the global ocean current system which brings water from the tropical Pacific into the Indian and the Atlantic oceans).
…CAGW, it would seem, is way down the likely suspects.