Swath sonar bathymetry data used for that dataset was recorded during RV MARIA S. MERIAN cruise MSM62/2 using Kongsberg EM1002 multibeam echosounder. The cruise took place between 23.03.2017 and 27.03.2017 in the Baltic Sea. The cruise aimed to investigate the impact of the Littorina transgression on the inflow of saline waters into the western Baltic and assessed the potential for future diminution of ventilation in the central and northern deeper basins due to isostatic uplift [CSR]. CI Citation: Paul Wintersteller (seafloor-imaging@marum.de) as responsible party for bathymetry raw data ingest and approval. During the MSM62/2 cruise, the moonpooled KONGSBERG EM1002 multibeam echosounder (MBES) was utilized to perform bathymetric mapping in shallow depths. The echosounder has a curved transducer in which 111 beams are formed for each ping while the seafloor is detected using amplitude and phase information for each beam sounding. For further information on the system, consult https://www.km.kongsberg.com/. Postprocessing and products were conducted by the Seafloor-Imaging & Mapping group of MARUM/FB5, responsible person Paul Wintersteller (seafloor-imaging@marum.de). The open source software MB-System (Caress, D. W., and D. N. Chayes, MB-System: Mapping the Seafloor, https://www.mbari.org/products/research-software/mb-system, 2017) was utilized for this purpose. A sound velocity correction profile was applied to the MSM62/2 data; there were no further corrections for roll, pitch and heave applied during postprocessing. A tide correction was applied, based on the Oregon State University (OSU) tidal prediction software (OTPS) that is retrievable through MB-System. CTD measurements during the cruise were sufficient to represent the changes in the sound velocity throughout the study area. Using Mbeditviz, artefacts were cleaned manually. NetCDF (GMT) grids of the edited data as well as statistics were created with mbgrid. The published bathymetric EM1002 grid of the cruise MSM62/2 has a resolution of 15 m. No total propagated uncertainty (TPU) has been calculated to gather vertical or horizontal accuracy. A higher resolution is, at least partly, achievable. The grid extended with _num represents a raster dataset with the statistical number of beams/depths taken into account to create the depth of the cell. The extended _sd -grid contains the standard deviation for each cell. The DTMs projections are given in Geographic coordinate system Lat/Lon; Geodetic Datum: WGS84.
Swath sonar bathymetry data used for that dataset was recorded during RV MARIA S. MERIAN cruise MSM51/1 using Kongsberg EM1002 multibeam echosounder. The cruise took place between 01.02.2016 and 27.02.2016 in the Baltic Sea. The cruise aimed to perform seismo- and hydroacoustic surveys, sampling of Holocene sediments and to investigate the water column wintertime mixing close to sea-ice limits. These surveys improved the understanding of variations in the ventilation of the deeper Baltic, considering not only external climate forcing but also the effects of postglacial sealevel rise and isostatic uplift [CSR]. CI Citation: Paul Wintersteller (seafloor-imaging@marum.de) as responsible party for bathymetry raw data ingest and approval. During the MSM51-1 cruise, the moonpooled KONGSBERG EM1002 multibeam echosounder (MBES) was utilized to perform bathymetric mapping in shallow depths. 111 beams are formed for each ping while the seafloor is detected using amplitude and phase information for each beam sounding. For further information on the system, consult https://www.km.kongsberg.com/. Postprocessing and products were conducted by the Seafloor-Imaging & Mapping group of MARUM/FB5, responsible person Paul Wintersteller (seafloor-imaging@marum.de). The open source software MB-System (Caress, D. W., and D. N. Chayes, MB-System: Mapping the Seafloor, https://www.mbari.org/products/research-software/mb-system, 2017) was utilized for this purpose. A sound velocity correction profile was applied to the MSM51-1 data; there were no further corrections for roll, pitch and heave applied during postprocessing. A tide correction was applied, based on the Oregon State University (OSU) tidal prediction software (OTPS) that is retrievable through MB-System. CTD measurements during the cruise were sufficient to represent the changes in the sound velocity throughout the study area. Using Mbeditviz, artefacts were cleaned manually. NetCDF (GMT) grids of the edited data as well as statistics were created with mbgrid. The published bathymetric EM1002 grid of the cruise MSM51-1 has a resolution of 15 m. No total propagated uncertainty (TPU) has been calculated to gather vertical or horizontal accuracy. A higher resolution is, at least partly, achievable. The grid extended with _num represents a raster dataset with the statistical number of beams/depths taken into account to create the depth of the cell. The extended _sd -grid contains the standard deviation for each cell. The DTMs projections are given in Geographic coordinate system Lat/Lon; Geodetic Datum: WGS84.
Bathymetry data based on the multibeam echosounders (MBES) KONGSBERG EM120 and EM1002 was conducted during R/V MARIA S. MERIAN cruise MSM16/3 between 13.10.2010 and 20.11.2010 in the Eastern Atlantic off Mauritania. The expedition aimed at a comprehensive understanding of the complex sedimentary system on the Mauritian Shelf as an atypical tropical eutrophic ecosystem and an archive of palaeoclimatic change in Africa during the Holocene. During the expedition, the chain of Mauritian coral reef mounds was mapped for the first time, carbonate-producing organisms successfully sampled and the flooding history of the Golfe d'Arguin investigated. Hydroacoustic surveys were conducted for a better understanding of the topography, and particularly for the identification of coral mounds and their morphological and structural patterns. In addition to bathymetric mapping, further instruments complemented the research programme, such as the sub-bottom profiler PARASOUND, a fast-rescue boat for shallow water surveys, various sediment sampling and coring devices, a CTD, an aerial dust collector and a remotely operated vehicle (ROV).
CI Citation: Paul Wintersteller (seafloor-imaging@marum.de) as responsible party for bathymetry raw data ingest and approval.
Description of the data source:
During the MSM16/3 expedition, the KONGSBERG EM1002 multibeam ecosounder (MBES) was utilized for high-resolution bathymetric mapping in water depths from 30 to 800m. A semi-circular transducer array with a radius of 45 cm and 160° angular extent transmits a nominal sounding frequency of 95 kHz with a maximum angular coverage sector of 150°. During the reception, 111 beams with widths of 2° by 2.3° are formed. Depending on the reflectivity of the seafloor, the swath width can reach up to 7.4 times the water depth. During the cruise, the angular coverage sector and beam pointing angles were set to vary automatically with depth according to achievable coverage in order to maximize the number of usable beams. The depth of the water column is calculated through the two-way-travel time, beam angle and ray bending due to refraction in the water column by sound speed variations. Combining amplitude (for central beams) and phase (for slant beams) provides accuracy practically independent of the beam-pointing angle. For further information on the system, consult https://www.km.kongsberg.com/.
Responsible persons during this cruise / PI: Andre Freiwald (andre.freiwald@senckenberg.de), Till Hanebuth (thanebuth@coastal.edu) & Stephen Schilling
Chief Scientist: Hildegard Westphal (hildegard.westphal@zmt-bremen.de)
CR: https://www.tib.eu/en/search/id/awi%3Adoi~10.2312%252Fcr_msm16_3/
CSR: https://www2.bsh.de/aktdat/dod/fahrtergebnis/2010/20100362.htm