ABSOLUTE GRAVIMETER FG5 NO. 215 AT THE GEODETIC OBSERVATORY PECNY

Absolute gravity measurements have been performed at the Geodetic Observatory Pecny since 1978. The absolute ballistic gravimeter FG5 No. 215 was acquired in 2001. This instrument has been used for repeated gravity measurements at the observatory. An annual variation of gravity was detected analyzing a two-year series of gravity measurements. The amplitude of this annual gravity variation is 22 nms(-2). In order to explain this affect, results of the gravity measurements were compared with hydrological and meteorological parameters recorded at the observatory such as a height of the ground water level, precipitation and soil moisture.