摘要：In recent decades, rapid ice shelf disintegration alongthe Antarctic Peninsula has had a global impact through enhancingoutlet glacier flow and hence sea level rise and the freshening ofAntarctic Bottom Water. Ice shelf thinning due to basal melting results fromthe circulation of relatively warm water in the underlying ocean cavity.However, the effect of sub-shelf circulation on future ice shelf stabilitycannot be predicted accurately with computer simulations if the geometry ofthe ice shelf cavity is unknown. To address this deficit for Larsen C IceShelf, West Antarctica, we integrate new water column thickness measurementsfrom recent seismic campaigns with existing observations. We present thesenew data here along with an updated bathymetry grid of the ocean cavity. Keyfindings include a relatively deep seabed to the southeast of the KenyonPeninsula, along the grounding line and around the key ice shelfpinning-point of Bawden Ice Rise. In addition, we can confirm that thecavity's southern trough stretches from Mobiloil Inlet to the open ocean.These areas of deep seabed will influence ocean circulation and tidalmixing and will therefore affect the basal-melt distribution. These resultswill help constrain models of ice shelf cavity circulation with the aim ofimproving our understanding of sub-shelf processes and their potentialinfluence on ice shelf stability. The datasets are comprised of all the new point measurements of seabed depth. Wepresent the new depth measurements here, as well as a compilation ofpreviously published measurements. To demonstrate the improvements to thesub-shelf bathymetry map that these new data provide we include a griddeddata product in the Supplement of this paper, derived usingthe additional measurements of both offshore seabed depth and the thicknessof grounded ice. The underlying seismic datasets that were used todetermine bed depth and ice thickness are available athttps://doi.org/10.5285/315740B1-A7B9-4CF0-9521-86F046E33E9A(Brisbourne et al., 2019), https://doi.org/10.5285/5D63777D-B375-4791-918F-9A5527093298 (Booth,2019), https://doi.org/10.5285/FFF8AFEE-4978-495E-9210-120872983A8D(Kulessa and Bevan, 2019) and https://doi.org/10.5285/147BAF64-B9AF-4A97-8091-26AEC0D3C0BB(Booth et al., 2019).
