2 research outputs found
Relevance of field observations as boundary conditions for understanding ice-sheet-ocean interactions
The direct contact of warm ocean water with the front and base of ice shelves is the main driver for accelerated mass loss of the
Antarctic ice sheet. We present a compilation of observations from various projects and methodological approaches applied
over the last decade along the Dronning Maud Land coast and highlight their importance for understanding the ice-ocean
interactions. With a focus on the Ekström ice shelf, these include spatially continuous seismic observations in combination with
airborne gravity inversion to yield sub-shelf bathymetry and geomorphological evidence of past ice-flow activity; ice-dynamic
numerical modelling to investigate the role of seafloor/subglacial substrate characteristics to enhance or reduce ice-sheet
extent and advance/retreat rates; sub-shelf CTD measurements to determine ocean properties driving basal melting; satellitebased
remote sensing to determine ice-shelf height changes and spatially-distributed basal melting; and point measurements of
basal melt with surface-based phase-sensitive radar to determine ocean-driven melt and validate remote-sensing products. As
the Dronning Maud Land coast plays a critical role in preconditioning the water mass of the coastal current before it enters the
Filcher ice-shelf cavity, we argue that a coordinated inter- and transdisciplinary observational network is required to facilitate
monitoring a potential ice-sheet mass loss in this part of Antarctica
Interpretation of geomorphological features underneath Ekströmisen, Antarctica in their glacio-geological context
The aim of this Master Thesis is to reconstruct the glacio-geological history of the
Ekström ice shelf on the basis of subglacial characteristics. This investigation provide
clues to past ice dynamics, which may contribute to the valuation of sea level rise due to
climate change in subsequent studies. The interpretation of these morphologies at the
sea floor was performed with the geophysical methods swath bathymetry, Parasound
and reflection seismics. The investigations were supported by the calculation of the sea
bed roughness at the seismic profiles. The landforms were used to identify advance and
retreat behaviours and phases of still-stand, draw conclusions about the substrate
and compare the findings with other Antarctic ice shelves. Channel structures imply
the presence of meltwater and thus changes in the thermal regime of the glacier base.
The detailed results can contribute to a better understanding of the behaviour and
to more reliable estimates for future responses of the East Antarctic ice shelves to
environmental change