Data from: The influence of sea ice, wind speed and marine mammals on Southern Ocean ambient sound

• Main Authors: Menze, Sebastian, Zitterbart, Daniel P., Van Opzeeland, Ilse, Boebel, Olaf
• Format: Dataset
• Language: unknown
• Published: 2016
• Subjects: ocean ambient sound; Antarctic marine mammals; sea ice; Southern Ocean; ocean ambient noise; Antarctic; The Antarctic; Austral; Greenwich; Hydrurga; Antarc*; Antarctic Minke whale; Balaenoptera bonaerensis; Balaenoptera musculus; Balaenoptera physalus; Fin whale; Hydrurga leptonyx; Leopard Seals; minke whale; Sea ice
• Online Access: https://zenodo.org/record/4989942; https://doi.org/10.5061/dryad.83s93

This paper describes the natural variability of ambient sound in the Southern Ocean, an acoustically pristine marine mammal habitat. Over a 3-year period, two autonomous recorders were moored along the Greenwich meridian to collect underwater passive acoustic data. Ambient sound levels were strongly affected by the annual variation of the sea-ice cover, which decouples local wind speed and sound levels during austral winter. With increasing sea-ice concentration, area and thickness, sound levels decreased while the contribution of distant sources increased. Marine mammal sounds formed a substantial part of the overall acoustic environment, comprising calls produced by Antarctic blue whales (Balaenoptera musculus intermedia), fin whales (Balaenoptera physalus), Antarctic minke whales (Balaenoptera bonaerensis) and leopard seals (Hydrurga leptonyx). The combined sound energy of a group or population vocalizing during extended periods contributed species-specific peaks to the ambient sound spectra. The temporal and spatial variation in the contribution of marine mammals to ambient sound suggests annual patterns in migration and behaviour. The Antarctic blue and fin whale contributions were loudest in austral autumn, whereas the Antarctic minke whale contribution was loudest during austral winter and repeatedly showed a diel pattern that coincided with the diel vertical migration of zooplankton. Ambient sound data from mooring AWI_230_6A NetCDF file containing the ambient sound spectra and metadata from mooring AWI_230_6AWI_230_6_ambient_sound_data.ncAmbient sound data from mooring AWI_232_9A NetCDF file containing the ambient sound spectra and metadata from mooring AWI_232_9AWI_232_9_ambient_sound_data.ncMatlab code used to analyse and visualize the ambient sound dataThis Matlab code calculates the results and plots the figures presented in the paper. Step-by-step instructions are provided as comments in the code, as well as links to external data sets. The code was developed and tested using Matlab ...