[J01-2] Monitoring of the cryosphere II

[J01-2-03] Geodetic studies of GIA and ice sheet changes by JARE

^○Yoichi Fukuda¹, Yuichi Aoyama², Koichiro Doi², Hideaki Hayakawa², Jun'ichi Okuno², Jun Nishijima³, Takahito Kazama¹, Keiko Yamamoto⁴, Toshihiro Higashi⁵, Kazuo Shibuya² (1.Kyoto University, Kyoto, Japan, 2.National Institute of Polar Research, Tokyo, Japan, 3.Kyushu University, Fukuoka, Japan, 4.National Astronomical Observatory, Tokyo, Japan, 5.TeraGrav LLC, Kyoto, Japan)

invited

The Antarctic ice sheet, which relates to the global climate changes through the sea level rise and ocean circulation, is an essential element of the Earth system for predicting the future environment changes. Thus many studies of the ice sheet changes have been conducted by means of in-situ geodetic observations, satellite observations such as satellite gravimetry and satellite altimetry as well. For these studies, one of the largest uncertainties is the effects of GIA, which, on the other hand, includes valuable information about the rheological properties of the solid Earth, because GIA is the rheological response of the solid Earth to the ice mass loading. The observational studies of the GIA effects should also contribute to investigate the inner structure of the Earth.
In view of these points, JARE (Japanese Antarctic Research Expedition) have been conducting absolute gravity measurements, GNSS and other geodetic observations at Syowa station and surrounding areas in East Antarctica. In particular, repeated absolute gravity measurements and continuous GNSS observations at Syowa station have been conducted since 1995, and these observation have revealed the temporal variations in both gravity and GNSS measurements due to the GIA. JARE also succeeded the absolute gravity measurement at Langhovde during 2011/2012 austral summer, which was the first outdoor measurement by JARE. Subsequently, JARE performed the outdoor absolute gravity measurement at Selungen, the central parts of the Sor Rondane Mts., during 2013 austral summer.
In this paper, related to the studies of GIA and ice sheet changes, we report the geodetic observations so far made by JARE, and the future plans as well.