Towards an accurate mean sea level to ellipsoid separation model for the Dutch Caribbean: an operational vessel based GNSS approach

Abstract

This contribution demonstrates the applicability of vessel-based GNSS measurements for deriving a regional Mean Sea Level (MSL)-ellipsoidal separation model in the Dutch Caribbean. Legacy hydrographic survey data from the 2019 Caribbean survey campaign is combined with tidal observations, predicted tides, and satellite altimetry to address limitations of global satellite-derived MSL models in complex coastal environments. Vessel-derived separation values show close agreement with shore-based benchmarks after correction for Sea Level Rise, Vertical Land Movement, and seasonal variability, with residuals typically within a few centimetres. The results confirm vessel-based separation measurements as a practical solution for establishing vertical control in data-sparse coastal regions, supporting hydrographic surveying, coastal management, and sea-level adaptation in Small Island Developing States.