A High-Resolution Gravimetric Geoid Model for Kuwait Using the Least-Squares Collocation

Hamad Al-Ajami,Mostafa Rabah,Ahmed Zaki,Mohamed El-Ashquer

doi:10.3389/feart.2021.753269

Abstract

A new gravimetric geoid model, the KW-FLGM2021, is developed for Kuwait in this study. This new geoid model is driven by a combination of the XGM2019e-combined global geopotential model (GGM), terrestrial gravity, and the SRTM 3 global digital elevation model with a spatial resolution of three arc seconds. The KW-FLGM2021 has been computed by using the technique of Least Squares Collocation (LSC) with Remove-Compute-Restore (RCR) procedure. To evaluate the external accuracy of the KW-FLGM2021 gravimetric geoid model, GPS/leveling data were used. As a result of this evaluation, the residual of geoid heights obtained from the KW-FLGM2021 geoid model is 2.2 cm. The KW-FLGM2021 is possible to be recommended as the first accurate geoid model for Kuwait.

Highlights

The geoid is an important surface to use in geomatics, geophysics, geodesy, and several Earth sciences
The longwavelength components are obtained from the global geopotential model (GGM), and the medium wavelength is derived from gravity information captured from terrestrial, shipborne, and airborne, as well as some satellite gravity missions
The “remove” step for geoid determination in the RCR includes the elimination of the GGM and topographic contribution from the observed anomalies as Eq 1 (HofmannWellenhof and Moritz, 2006): Δgres ΔgFA − ΔgGGM − ΔgRTM

Summary

Introduction

The geoid is an important surface to use in geomatics, geophysics, geodesy, and several Earth sciences. In geodesy, it plays an important role as a fundamental datum of the heights (Sansò and Sideris, 2013). GNSS offers accurate geodetic measurements in significantly less time. GNSS is a 3-D system that provides ellipsoidal heights relative to the ellipsoid surface. Ellipsoidal heights are just a geometrical quantity, and its conversion to orthometric height using the geoid model is widely used in almost all day-to-day applications requiring height information (Torge and Müller, 2012; Sansò and Sideris, 2013)

Objectives

Methods

Findings

Conclusion