Long-term monitoring of the Filchner Ice Shelf system

• Main Authors: Hattermann, Tore, Schröder, Michael, Hellmer, Hartmut
• Format: Conference Object
• Language: unknown
• Published: 2017
• Subjects: Antarc*; Antarctic; British Antarctic Survey; Ice Shelf
• Online Access: https://epic.awi.de/id/eprint/44973/; https://hdl.handle.net/10013/epic.51246

During the austral summer seasons 2015/16 an 2016/17, the Alfred Wegener Institute in collaboration with the British Antarctic Survey and the University of Bergen drilled four access holes through 850-900-m thick ice on both sides of the southern Filchner Ice Shelf (FIS) and three holes through about 600-m thick ice on its northeastern part, respectively. The holes have been equipped with current meters, temperature and salinity sensors, and thermistor chains, distributed over the whole water column and within the ice to monitor the hydrography in the cavity, the exchange of heat and salt across the boundary layer close to the ice shelf, and the thermal conditions in the ice for a maximum period of five years (depending on battery lifetime). Since the instruments are attached to an inductive cable, data are stored at the ice shelf surface and transmitted via Iridium to AWI every night. First analysis shows that two regimes exist underneath FIS with the southern regime similarly exhibiting a two-layered water column with a highly variable pycnocline and the northern regime showing a stronger zonal variability and the inflow of warmer waters at mid-depth. The whole FIS cavity is subject to strong diurnal and semidiurnal tidal forcing causing pronounced forthnighty resonances with velocities up to 40 cm/s and a daily displacement of the pycnocline by several tens of meters at the southern sites.