Abstract
K-NOW: Korea Network for Observation and prediction of ice sheet and sea level changes in a Warming world
ABS Webinar November 2022
Won Sang Lee
(
Division of Glacial Environment Research, Korea Polar Research Institute
According to the IPCC Sixth Assessment Report, we are experiencing unprecedented rapid changes, such as ice melting in Polar regions and sea level rise. In particular, Antarctica is currently losing six times more ice mass annually compared to the situation 40 years ago, thought to be induced by climate change. Moreover, the IMBIE project reported combining satellite observations in 2018 that Antarctica lost 2720 ± 1390 billion tonnes of ice, equivalent to an increase in global sea levels by 7.6 ± 3.9 mm between 1992 and 2017. Ice shelves surround 75% of coastlines in Antarctica and play a critical role in slowing down the movement speed of glaciers upstream by buttressing. They are, however, vulnerable to ocean-driven melting, which is significantly occurring in the West Antarctic. Therefore, a better understanding of the physical processes associated with the interaction between ocean and ice shelves is vital to assessing the stability of the ice shelves and reducing uncertainties in projecting future sea level rise. The Korea Polar Research Institute launched a large-scale research project called LIONESS-TG (Land-Ice/Ocean Network Exploration using Semiautonomous Systems, Thwaites Glacier) in 2019 and conducted extensive field surveys in 2019/2020 and 2021/2022 seasons. More than 20 participants from 5 countries joined cruises and successfully collected valuable data sets. A couple of highlights of the latest expedition would be that we have; 1. found the warmest circumpolar deep water near the grounding zone by dropping XCTDs from a helicopter, 2. successfully drilled an access hole through the Dotson Ice Shelf (~400-500m thickness) and deployed hydrographic mooring to make direct measurements underneath the ice shelf, 3. attached CTD sensors to Weddell seals to measure continuous ocean properties that could provide us with invaluable year-round data sets in the study region. In addition to presenting the LIONESS-TG marine operations described above, I would share and discuss our on-going land-based activities (e.g. subglacial hydrology, PGR, etc.) and future research plans beyond 2022—K-NOW.