Effects of Troposphere on Horizontal Vector of GPS Baseline Determination

Abstract

Excess pass delay (EPD) in the troposphere on Takayama-Nagoya and Takayama-Hachijo baselines was estimated from the surfacemeteorological condition using with the Hopfield model in February, May, August and November 1992. Longterm repeatability of the horizontal vectors on the two baselines is improved by 3 to 6 mm by the correction of EPD. North-South components of the baseline vectors show a seasonal variation of 10 to 32 mm in August 1992. It is clear that the correction of EPD is necessary to discuss GPS measurements with an accuracy of 1×10^-7.