Raw multibeam bathymetry data were collected aboard RV MARIA S. Merian during cruise MSN139 using a Kongsberg EM 712 multibeam echosounder. The expedition took place during 2025-07-25 – 2025-08-27 from Reykjavik (Iceland) to Reykjavik (Iceland) in the North Atlantic. The overall goal of MSM139 was to investigate the interactions between hydrography, bio-optics, planktonic composition and community connectivity (especially toxigenic algae and their toxins). This is in combination with environmental genomic approaches (metatranscriptomics, metabarcoding, population genomics, paleometagenomics) conducted in five research areas in West Greenland fjords and coastline which differ in their ice coverage, glacial melt water runoffs, and history. The survey results will be used to estimate quantifiable effects of harmful algae blooms on the ecosystem, which are driven by an accelerated glacial melt water runoff. In addition, sediments will be examined for resting stages (cysts) and paleo-communities, focusing on toxigenic species. Data were recorded within the Danish EEZ (Greenland). Sound velocity profiles (SVP) were applied on the data for calibration. Please see environmental data and the cruise report for details. The data are unprocessed and can therefore contain incorrect depth measurements (artifacts) if not further processed. Note that refraction errors may occur when no proper SVP is applied. Data acquisition was done by AWI, provision of the data is supported by the DAM Project Underway Research Data and published according to the FAIR principles.

These data should not be used for navigational purposes.