Deployment of AUV in the Amundsen Sea on RVIB Araon / KOPRI Cruise 2023/2024

Thwaites Glacier Expedition 2023–2024 (ANA14B)

An international expedition, led by Chief Scientist Won Sang Lee from KOPRI, and hosting participants from Korea, Sweden, UK, US, Australia and China, took place aboard the Korean icebreaker RVIB Araon between December 28, 2023, to February 15, 2024.

Photo: cruise participants

The focus of the expedition was Thwaites Glacier and the two adjacent ice shelves in the Amundsen Sea, Dotson ice shelf and Getz ice shelf. This is a region where the Antarctic ice sheet is particularly vulnerable to warming, and the expedition contained a multifaceted scientific effort to better understand ongoing changes. The expedition enabled two large deliverables to OCEAN:ICE, deliverable 2.2 and 2.3.

Key components of the expedition included:

  • Land-Based Measurements: Advanced radar (ApRES) and GPS systems were installed to monitor glacier melting and bedrock uplift, with a focus on improving long-term observations in remote, understudied areas.
  • A Korean-US ice core drilling camp was set up at Canisteo Peninsula, where two 150 m long ice cores were successfully retrieved. They will be used to get information about the history of the West Antarctic ice sheet.
  • Aerial Surveys: Helicopter-mounted radar systems mapped over 3,200 kilometres of ice and subglacial features, identifying geological structures and areas of active subglacial hydrology. A program where aerial drones surveyed the pinning point of Thwaites Eastern Ice Shelf with infrared and high-resolution cameras was also conducted.
  • Oceanography: Researchers deployed oceanographic equipment from helicopters and ships to collect data on temperature, salinity, and meltwater distribution, shedding light on ice melt caused by warm ocean currents.
  • Moorings: A number of moorings that have been placed in the water for several years to collect data of current speed, water temperature, salinity, and seismic activity, were successfully recovered.
  • Ice cavity exploration: The autonomous underwater vehicle (AUV) Ran conducted five missions beneath the Thwaites and Dotson ice shelves. Despite the loss of the AUV towards the end of the expedition, valuable and unique data of the underside of the ice, melt patterns, and detailed information about the seabed was obtained.
  • Sea Ice work: Korean and UK teams collected ice cores, studied microbial life, and tagged seals with sensors to monitor oceanographic changes in the months to come.

The expedition marked significant progress in understanding the complex processes affecting the coastal components of the West Antarctic Ice Sheet. The data collected offer critical inputs for refining predictions of glacier behaviour and future sea level rise, and will be used in years to come in studies of the West Antarctic Ice Sheet and its impact on climate, sea level, and the marine coastal system around Antarctica.

The author of the article - Anna Wåhlin (University of Gothenburg)