Shipboard Marine Gravimeters Operated on Vessels in the U.S. Academic Research Fleet: Capabilities and Data Quality

Abstract Shipboard gravity anomaly data provide high‐resolution information for a wide range of Earth and ocean science research as well as ground‐truthing US national geodetic modeling. Motivated by the end of life‐cycle for legacy Bell aerospace marine Gravity Meter system (BGM‐3) gravimeters onboard vessels in the U.S. Academic Research Fleet, a new generation of marine gravimeters from Dynamic Gravity Systems (DGS) was introduced as replacements. We describe the technical functions of this new generation of marine gravimeter and describe an open‐source post‐processing software package with a simple workflow that users can adapt for processing and assessing data quality along with recommendations on the basis of ∼5 years of operational experience with the DGS meter. We demonstrate the capability of the DGS marine gravimeter using data from expeditions conducted on the R/V Atlantis and RVIB N. B. Palmer that experienced various sea state and operation modes, including open‐water, dynamic positioning, and ice‐breaking conditions. DGS data collected during both cruises are internally consistent using crossover error analysis. Comparisons between the DGS meter and satellite‐derived gravity anomalies imply a constant offset. While shorter‐wavelength anomalies imply finer scale seabed features were well resolved, high frequency ship motions show that swell in the open ocean remains the main artifact contributor to marine gravity data that requires filtering. Quality assessments during different operational modes suggest that data recorded by DGS gravimeters are comparable to BGM‐3 data, with superior operational characteristics that facilitate a wide range of vessel and research requirements, and better logistical capabilities for global operations.