[G07-4] GGOS observations: GNSS and co-locations

[G07-4-02] Geodetic activities at Syowa Station, East Antarctica

^○Yuichi Aoyama¹, Koichiro Doi¹, Yoichi Fukuda², Hiroshi Ikeda³, Hideaki Hayakawa¹, Yoshihiro Fukuzaki⁴, Mamoru Sekido⁵, Toshimichi Otsubo⁶, Yoshifumi Nogi¹, Kazuo Shibuya¹ (1.National Institute of Polar Research, Tokyo, Japan, 2.Kyoto University, Kyoto, Japan, 3.University of Tsukuba, Ibaraki, Japan, 4.Geospatial Information Authority of Japan, Ibaraki, Japan, 5.National Institute of Information and Communications Technology, Tokyo, Japan, 6.Hitotsubashi University, Tokyo, Japan)

invited

Syowa Station, the main wintering base of the JARE (Japanese Antarctic Research Expedition), is located on East Ongul Island, Dronning Maud Land, East Antarctica. Three space geodetic observations with VLBI (Very Long Baseline Interferometry), GNSS (Global Navigation Satellite System) and DORIS (Doppler Orbitography and Radiopositioning Integrated by Satellite) have been carried out at Syowa Station since the 1990s and these observation sites are all distributed within 400m each other. We have also conducted repetitive absolute gravity measurements with FG-5 and temporal gravity change measurements with three serial superconducting gravimeters since early 1990s. For monitoring ocean tides and sea level, tidal observation with bottom pressure gauges has been continuing at Nisi-no-ura Cove, 700 m far from GNSS sites, since 1976. Their local ties have been surveyed with accuracy less than a few millimeter, except that vertical offset vector between GNSS and VLBI was determined with an uncertainty of 1 cm.

Those continuous geodetic observation data contributed to maintain international terrestrial reference frame and to detect crustal movement induced by glacial isostatic adjustment and recent surface mass changes on East Antarctic ice sheet. To enhance the geodetic observations, we start a feasibility study for installing SLR (Satellite Laser Ranging) system at Syowa Station.

In this study, we report the current geodetic activities of JARE at Syowa Station, and the future plans for contributing to GGOS as a co-location site in Antarctic region.