Water level reduction with GNSS [FIG Commission 4 Working Group 4.2 2006, Dodd and Mills 2011] requires the availability of the ellipsoidal heights of CD, i.e. the Lowest Astronomical Tide (LAT) as adopted by the International Hydrographic Organization [International Hydrographic Organization, 2011, Technical Resolution 3/1919]. LAT is defined as the lowest tide level to occur under average met...

According to wide spread use of satellite based positioning techniques, especially GPS (Global Positioning System), a greater attention has started to be paid to precise determination of geoid models with an aim to replace the geometric levelling measurements with GPS measurements during geodetic and surveying works. In this paper, geoid modelling is evaluated as a surface fitting problem accor...

The determination of the orthometric height from geometric leveling has practical difficulties that, despite a number of scientific and technological advances, passed a century without substantial modifications or advances. Currently, the Global Navigation Satellite System (GNSS) has been used with reasonable success for orthometric height determination. With a sufficient number of benchmarks w...

Satellite optical images and altimetry data are two major data sources used in Antarctic research. The integration use of these two datasets is expected to provide more accurate and higher quality products, during which data registration is the first issue that needs to be solved. This paper presents an alternative approach for the registration of high-resolution satellite optical images and IC...

Lake Turkana is one of the largest desert lakes in the world and is characterized by high degrees of interand intra-annual fluctuations. The hydrology and water balance of this lake have not been well understood due to its remote location and unavailability of reliable ground truth datasets. Managing surface water resources is a great challenge in areas where in-situ data are either limited or ...

Improved global mean sea level is obtained by combining two datasets: large-scale mean sea level based on measurements of twin-satellite mission GRACE and mesoscale sea level tilt derived from the momentum balance as seen in drifter, satellite altimeter and wind data. Hybrid product reveals complex structures of main currents even after averaging over 10 years and shows their places in the larg...