Study and Progress in Theories and Crucial Techniques of Modern Height Measurement in China

The scientific significance,function and application of geoid in geodesy and related geoscience are elaborated.The conception of combining GPS with high precision geoid to replace leveling in China is brought forward.The prerequisites of long wave,medium wave and short wave of Earth's gravity field to compute geoid with cm-level accuracy are analyzed.Some crucial techniques,necessity and feasibility of determining city geoid with 1 cm and provincial geiod with 5 cm are discussed.The main theoretical problems and mainly crucial techniques to be solved in cm-level geoid determination in China are presented as well.And the main progress and achievement of regional geoid determination in China are reviewed.