Project Title

RAPID: International Collaborative Research into Ice-ocean interactions & Fractures at Thwaites (ICE-RIFT)

Summary

Event Number:
I-352-E

Program Director:
Dr. David Porter

ASC POC/Implementer:
John Rand / Jane Dell

Principal Investigator(s)

Dr. Jamin S Greenbaum
jsg@ucsd.edu
University of California San Diego
Scripps Institution of Oceanography

Location

Supporting Stations: Special Project
Research Locations: Thwaites Glacier

Description

This project seeks to characterize the ocean nearby and underneath the Thwaites Glacier Tongue (TGT). The TGT's collapse between 2012-2016 has formed sequences of rifts with small areas of thin sea ice that, if broken, can be used to access the ocean below in areas where altimetry-based data indicate very rapid basal melt. The TGT is also an area where it is hypothesized that subglacial freshwater is discharged from beneath Thwaites Glacier. If freshwater discharge is indeed present in the sub-ice cavity, it is thought to enhance melt in the inner ~10km. Temperature and conductivity profiles acquired in early 2022 indicated ocean properties unlike any that had been observed in Antarctica before; conditions showing that the ocean had been heavily modified by melt processes within the cavity. Ocean sensors are to be deployed into the rifted TGT as close as possible to the grounding line to 1) evaluate the heat available for driving sustained melt in the TGT; 2) evaluate how the resulting meltwater modifies the stratification of the cavity waters (potentially driving higher melt rates at shallower depths); and 3) evaluate whether the water column properties indicate melt enhancement due to subglacial freshwater discharge.

Field Season Overview

Two USAP-sponsored researchers will be supported aboard the Korean Antarctic Program Institute (KOPRI) cruise to the TGT area by the KOPRI science vessel RV ARAON. This expedition is a continuation of KOPRI's work in the Amundsen Sea as part of the Korea Network for Observation and prediction of ice sheet and sea-level rise in a Warming world (K-NOW) program. The ARAON is scheduled to depart Lyttelton, New Zealand in late December 2023 with two AS-350 helicopters which will support the activities of the USAP participants. Airborne eXpendable Conductivity, Temperature, Depth (AXCTD) sensors will be deployed into rifts in the TGT located in five target areas throughout the TGT.

Deploying Team Members