High-resolution bathymetry from expedition Petermann, Northwest Greenland, 2015
Martin Jakobsson, Larry Mayer, Kelly Hogan, Björn Eriksson, Kevin Jerram, Christian Stranne
Multibeam bathymetry from seafloor off northwestern sector of the Greenland Ice Sheet, where Petermann Glacier drains into Nares Strait. The data reveal submarine glacial landforms in fjords, which tell us about the dynamic behaviour of fast-flowing marine-terminating glaciers.
High-resolution bathymetry data are commonly used to study, for example, general seafloor geology, glacial morphology, bottom habitats, and bottom current activities. The data were collected from Swedish icebreaker Oden during the Petermann 2015 expedition.
The bathymetry is acquired with a multibeam echo-sounder. The data are provided in the form of a compiled Digital Terrain Model with a grid cell size of 15 m. The processing of the raw data was carried out using the Qimera software by QPS.
Multibeam data from the Petermann fjord shows how far the glacier has extended in the past and how it later has retracted back to its current position. Sea floor morphology shows that the recession was not slow, but rather dramatic when the glacier collapsed in a process called Marine Ice Cliff instability. Before this, the glacier was stable at the fjord mouth for more than 1000 years.
We need to learn more about these processes and what conditions that make the glacier stable, in order to predict how glacier dynamics will be affected by a warming climate and thereby contribute to sea level rise.
At the fjord mouth a threshold is located, consisting of sediment deposited by the glacier. The threshold depth is one important factor that affects how vulnerable the glacier is to warmer water.
Citation
Martin Jakobsson, Larry Mayer, Kelly Hogan, Björn Eriksson, Kevin Jerram, Christian Stranne (2021) High-resolution bathymetry from expedition Petermann, Northwest Greenland, 2015. Dataset version 2. Bolin Centre Database. https://doi.org/10.17043/oden-petermann-2015-bathymetry-2
References
Jakobsson, M., Hogan, K.A., Mayer, L.A., Mix, A., Jennings, A., Stoner, J., Eriksson, B., Jerram, K., Mohammad, R., Pearce, C., Reilly, B., Stranne, C. (2018). The Holocene retreat dynamics and stability of Petermann Glacier in northwest Greenland. Nature Communications, 9(1), 1-11. https://doi.org/10.1038/s41467-018-04573-2
Hogan, K. A., Jakobsson, M., Mayer, L. A., Reilly, B. T., Jennings, A. E., Stoner, J. S., et al. (2020). Glacial sedimentation, fluxes and erosion rates associated with ice retreat in Petermann Fjord and Nares Strait, north-west Greenland. The Cryosphere, 14(1), 261-286. https://doi.org/10.5194/tc-14-261-2020
Jakobsson, M., Mayer, L.A., Bringensparr, C., Castro, C.F., Mohammad, R., Johnson, P., Ketter, T., Accettella, D., Amblas, D., An, L., Arndt, J.E., Canals, M., Casamor, J.L., Chauché, N., Coakley, B., Danielson, S., Demarte, M., Dickson, M.-L., Dorschel, B., Dowdeswell, J.A., Dreutter, S., Fremand, A.C., Gallant, D., Hall, J.K., Hehemann, L., Hodnesdal, H., Hong, J., Ivaldi, R., Kane, E., Klaucke, I., Krawczyk, D.W., Kristoffersen, Y., Kuipers, B.R., Millan, R., Masetti, G., Morlighem, M., Noormets, R., Prescott, M.M., Rebesco, M., Rignot, E., Semiletov, I., Tate, A.J., Travaglini, P., Velicogna, I., Weatherall, P., Weinrebe, W., Willis, J.K., Wood, M., Zarayskaya, Y., Zhang, T., Zimmermann, M., Zinglersen, K.B., 2020. The International Bathymetric Chart of the Arctic Ocean Version 4.0. Scientific Data 7, 176. https://doi.org/10.1038/s41597-020-0520-9
The bathymetric data are provided as processed grids, divided into survey areas, with a grid cell size of 15 m. The grids are provided both in polar stereographic projection (IBCAO Polar Stereographic, EPSG 3996, true scale at 75 degrees north) and unprojected WGS 84 and in geographic coordinates (latitude and longitude). The horizontal datum is WGS 84 and the vertical datum is instantaneous sea level, implying that the vertical level has not been corrected for tides. For each projection, the bathymetric data grids are available in four formats: GeoTiff, netCDF, ASCII XYZ and ESRI Arc ASCII grid. Data are also illustrated as JPEG images.
Comments
The data were acquired in summer 2015 from Swedish icebreaker (IB) Oden during the Petermann 2015 expedition. A Kongsberg EM122 1° × 1°, 12 kHz, multibeam echo-sounder was hull-mounted in IB Oden. Position, heading and attitude data were received from a Kongsberg-Seatex Seapath 320 navigation unit (GPS and GLONASS) with attached MRU5 motion sensor. The exact speed of sound at the multibeam transducers was provided by a Valeport Mini SVS/T sound speed and temperature sensor mounted in the sea-chest in Oden’s hull, close to the multibeam transducer arrays. This was interfaced with the multibeam system directly. In addition, sound speed profiles for the entire water column were provided by CTD (Conductivity, Temperature, Depth) stations as well as XBT (Expendable Bathy Thermograph) probes.
The data was collected in a mixture of sea-ice conditions, ranging from 5/10 to 8/10 coverage. Navigation was provided by a Seatex Seapath 320 without local augmentation as this is not available in the area. Sound speed correction was done regularly using data from a Seabird 911+ CTD (conductivity, temperature depth) or Valeport SVP (sound velocity profiler).
The Petermann expedition started and ended in Thule Airbase, Greenland, and lasted from July 28 to September 2, 2015. It focused on past variations of the ocean-ice-climate-sea level system to assess how the coupled system has responded to changing climate. Interagency and international collaborations included the US National Science Foundation (NSF), The Ocean Melting Greenland (OMG) project of US National Aeronautics and Space Administration (NASA), the British Antarctic Survey, University NAVSTAR Consortium (UNAVCO), the Polar Geospatial Center (PGC), the Swedish Polar Research Secretariat, and the Geological Survey of Denmark and Greenland.
Contact information
Email address
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Phone number
+46-8-164719
Postal address
Martin Jakobsson
Department of Geological Sciences Stockholm University
SE-106 91 Stockholm Sweden