Hornsund Fjord 2023: Broadband Active Acoustic and Oceanographic Data

The archive contains all data collected during the Hornsund Fjord 2023 expedition, which took place in Southwestern Svalbard. Hornsund Fjord 2023 aimed to characterize the thermohaline structure of a high latitude fjord through the collection of active acoustic and oceanographic data. This project is part of a larger research effort in Hornsund Fjord, Svalbard under the research permit 11023, "Measuring the melt rate of glacier ice with underwater noise (Ice melt from hydroacoustics)". This is a multi-year study with typically 6-week field deployments in Hornsund fjord, Svalbard designed to address 1) the distribution of gas pressures and bubbles sizes in glacier ice, 2) the variability in these distributions between glaciers, and 3) the variation of sound production from melting glacier ice versus depth below the sea surface and water temperature.

Data archived here include high frequency (150-250 kHz) broadband acoustic water column data collected with split-beam echosounders, conductivity-temperature-depth (CTD) profiles, and microstructure profiles. The broadband acoustic data consists of the raw complex pressure time series. The CTD profiles include temperature, salinity, density, sound speed, and depth profiles. The microstructure profiles include dissipation rates of both turbulent kinetic energy and temperature variance.

Elizabeth Weidner lead the acoustic data collection, with assistance from a large field team including researchers from Scripps Institution of Oceanography, the National University of Singapore, and the Institute of Geophysics in Poland. The data were collected in July of 2023 on board Marine Vessel (MV) Ulla Rinman. Cruise data include two types of acoustic water column data: full-fjord transects and glacial terminus scans. The full-fjord transects cover approximately 3 km, running N-S from the terminus of the glacier to the main channel of Hornsund Fjord. The glacial scans are approximately 1 km long, running E-W. CTD and microstructure casts are interspersed throughout the acoustic survey.