BEGIN:VCALENDAR VERSION:2.0 PRODID:researchseminars.org CALSCALE:GREGORIAN X-WR-CALNAME:researchseminars.org BEGIN:VEVENT SUMMARY:Anna Wåhlin (University of Gothenburg) DTSTART:20210113T140000Z DTEND:20210113T150000Z DTSTAMP:20260423T052953Z UID:BAS-PO/8 DESCRIPTION:Title: A n AUV underneath the ‘Doomsday glacier’: Revealing pathways and modifi cation of warm water flowing beneath Thwaites ice shelf\, West Antarctica< /a>\nby Anna Wåhlin (University of Gothenburg) as part of BAS Polar Ocean s Seminar\n\n\nAbstract\nThe fate of the West Antarctic Ice Sheet is the l argest remaining uncertainty in predicting sea-level rise through the next century\, and its most vulnerable and rapidly changing outlet is Thwaites Glacier. Because the seabed slope under the glacier is retrograde (downhi ll inland)\, ice discharge from Thwaites Glacier is potentially unstable t o melting of the underside of its floating ice shelf and grounding line re treat\, both of which can be enhanced by warm ocean water circulating unde rneath the ice shelf. Here we present the results of two missions undernea th Thwaites ice shelf performed by the AUV ‘Ran’: The very first direc t observations of ocean temperature\, salinity\, and oxygen underneath Thw aites ice shelf. Using the high precision environment payload suite\, obse rvations were obtained that indicate deep water (> 800 m) underneath the c entral part of the ice shelf is in connection with Pine Island Bay\, a pre viously unknown westward branch of warm deep water entering the ice shelf cavity. Warm water also enters from the north in two troughs separated by a pinning point. Spatial gradients of salinity\, temperature and oxygen re corded underneath the ice shelf indicate that this is an active region whe re several water masses meet and mixes. The observations identify the cent ral buttressing point as a vulnerable region of change currently under att ack by warm water inflow from all sides: a scenario that may lead to ungro unding and retreat more quickly than previously expected.\n LOCATION:https://researchseminars.org/talk/BAS-PO/8/ END:VEVENT END:VCALENDAR