Local geoid computation and evaluation

A local geoid solution for the northern part of Greece is presented based o n a recent processing of newly available gravity data in the area 40.25 les s than or equal to phi less than or equal to 41.00, 22.5 less than or equal to lambda less than or equal to 24.25. The derived gravimetric geoid heigh ts are compared with geoid heights computed at recently measured GPS/leveli ng benchmarks. A 4-parameter transformation model is applied to the differe nces between the two aforementioned geoid height sets, and a discussion is given on the current state of the leveling datum in the test area and the G reek territory. Regional and local transformation parameters are computed a nd some numerical tests are performed. A common adjustment of gravimetric g eoid heights and corresponding GPS/leveling heights will be carried out in another study following an integrated procedure in order to study problems arising from the combination of different height data sets for geoid determ ination. Finally, some conclusions are drawn on the problems related to the optimization of a local geoid solution. (C) 2000 Elsevier Science Ltd. All rights reserved.