Subaerial and submarine frontal morphology of Kronebreen, Svalbard, 24 August 2016

Riko Noormets, Michał Pętlicki, Nina Kirchner

The dataset consists of two profiles of the frontal morphology of Kronebreen, Svalbard, measured on 24 August 2016. The data was recorded using LiDAR (above the waterline) and multibeam (below the waterline).

Profile 1 corresponds to the location of a subglacial plume, where frontal melt rates are expected to be high. Profile 2 does not correspond to the location of a subglacial plume. These profiles can be used to look at the frontal geometry of a calving glacier and, when compared to each other, give a sense of how the calving front morphology can vary across a glacier. When using both the LiDAR and multibeam data, information on undercut sizes can be gleaned.

The data is presented as four comma-separated values files. Each profile consists of two files, one for the LiDAR data and one for the multibeam data.

Citation

Riko Noormets, Michał Pętlicki, Nina Kirchner (2022) Subaerial and submarine frontal morphology of Kronebreen, Svalbard, 24 August 2016. Dataset version 1. Bolin Centre Database. https://doi.org/10.17043/noormets-2022-kronebreen-1

Data description

The dataset consists of two profiles of the frontal morphology of Kronebreen, Svalbard, on 24 August 2016. Both profiles were mapped using a Riegl VZ-6000 terrestrial LiDAR for areas above the waterline, and using a Kongsberg EM2040 multibeam (MB) echosounder for areas below the waterline.

The profiles are given as four separate comma-separated values (.csv) files with three columns. Each profile is presented in two files; one with the LiDAR data and one with the multibeam data. Each file is between 4 and 40 kB in size. The columns in each .csv file contain:

• Column 1: Easting (UTM zone 33N)
• Column 2: Northing (UTM zone 33N)
• Column 3: Elevation above sea level (m)

Profile 1 runs on a transect from Easting 448001 to Easting 448057. Soundings for this profile are taken between Northings 8756133 and 8756134.

Profile 2 runs on a transect from Easting 448000 to Easting 448050. Soundings for this profile were taken between Northings 8756633 and 8756634.

Comments

The Riegl VZ-6000 LiDAR is equipped with a long-range near-infrared laser and calculates the distance to an object using the time-of-flight principle. For the data presented here, a pulse repetition rate (PRR) of 50 kHz was used, with both the horizontal and vertical angular resolution at 0.0045 degrees. The effective resolution was around 80 cm in the horizontal direction and around 30 cm in the vertical direction as a result of poor meteorological conditions, a complex survey geometry, and poor reflection from the ice cliff. According to the manufacturer, the LiDAR has a distance accuracy of 10 mm and precision of 15 mm at a range of 150 m. No laser return was obtained at the waterline due to greatly reduced near-infrared reflectivity as a consequence of water action and water spray. Overall, based on previously published surveys of the ice cliffs, we conservatively estimate the measurement uncertainty at 30 cm.

Submarine parts of the glacier face were mapped using a Kongsberg’s EM2040 multibeam echosounder mounted on a small, 15-m research vessel “Viking Explorer”. The EM2040 is a wide band high resolution shallow water mutibeam echosounder with one 0.4° wide transmit beam and 256 0.7° wide receiver beams. The echosounder was operated at 200 kHz frequency with sampling frequency varying usually between 5⁠ – ⁠10 Hz being limited by water depth. The range resolution varyed depending on the pulse type used but was usually within 1⁠ – ⁠2 cm. The EM2040 was coupled with Kongsberg’s Seapath 330+ Global Navigation and Satellite System (GNSS) positioning and Motion Reference Units (MRU). Positioning was aided by a local Real Time Kinematic (RTK) reference station placed on a nearby coastal area resulting in a positioning accuracy of better than 10 cm.

The data presented here were part of the data collected during the project Glacier dynamic ice loss quantified through seismic eyes (CalvingSEIS) (PI: Christopher Nuth) funded by the Research Council of Norway. The data are also related to the project Tidewater glacier marginal environments and processes (PI: Riko Noormets).

The LiDAR data was mapped by Michał Pętlicki. The Multibeam data was collected by Riko Noormets and Nina Kirchner.

Data creators' affiliations

Riko Noormets: Department of Arctic Geology, University Centre in Svalbard, Longyearbyen, Norway.

Michał Pętlicki: Faculty of Geography and Geology, Jagiellonian University in Kraków, Cracow, Poland.

Nina Kirchner: Department of Physical Geography, Stockholm University, Sweden.