• Journal of the Korean earth science society
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• v.32 no.7
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• pp.719-731
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• 2011

Based on the ICE-3G and ICE-5G ice models, we predicted the velocities of crustal uplift caused by Glacial Isostatic Adjustment (GIA) at 39 tide gauge sites operated by Korea Hydrographic and Oceanographic Administration (KHOA). We also divided the Korean peninsula in the ranges of $32-38.5^{\circ}N$ and $124-132^{\circ}E$ in $0.5^{\circ}{\times}0.5^{\circ}$ grids, and computed the GIA velocities at each grid point. We found that the average uplift rates due to GIA in South Korea were 0.33 and 1.21 mm/yr for ICE-3G and ICE-5G, respectively. Because the GIA rates were relatively high at ~1 mm/yr when the updated ice model ICE-5G was used, we concluded that the GIA effect cannot be neglected when we compute the absolute sea level (ASL) rates around the Korean peninsula. In this study, we corrected the ICE-5G GIA velocities from the relative sea level rates provided by KHOA and we computed the ASL rates at 13 tide gauge stations. As a result, we found that the average ASL velocity around the Korean peninsula was 5.04 mm/yr. However, the ASL rates near Jeju island were abnormally higher than the other areas and the average was 8.84 mm/yr.

• Korean Journal of Remote Sensing
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• v.21 no.1
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• pp.51-57
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• 2005

The currently operating NASA/GFZ Gravity Recovery and Climate Experiment (GRACE) mission is designed to measure small mass changes over a large spatial scale, including the mapping of continental water storage changes and other geophysical signals in the form of monthly temporal gravity field. The European Space Agency's Gravity field and steady state Ocean Circulation Explorer (GOCE) space gravity gradiometer (SGG) mission is anticipated to determine the mean Earth gravity field with an unprecedented geoid accuracy of several cm (rms) with wavelength of 130km or longer. In this paper, we present a summary of present GRACE studies for the recovery of hydrological signals in the Amazon basin using alternative processing and filtering techniques, and local inversion to enhance the temporal and spatial resolutions by two-folds or better. Simulation studies for the potential GRACE detection of slow deformations due to Nazca-South America plate convergence and glacial isostatic adjustment (GIA) signals show that these signals are at present difficult to detect without long-term data averaging and further improvement of GRACE measurement accuracy.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.27 no.3
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• pp.375-384
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• 2009

The GRACE satellite, Launched in March 2002, is applied to research on glacial melt of polar regions, glacial isostatic adjustment(GIA), sea level change, terrestrial water storage(TWS) variation of river basin and large-scale earthquake etc. In this research, the TWS variation of Yangtze river basin from August, 2002 to January, 2009 is analyzed using Level-2 GRACE monthly gravity field model. Particularly, gravity changes of the Three Gorges Dam during the impoundment process in 2003, 2006 and 2008 is observed by estimating equivalent water thickness(EWT). The research results show the distinct annual and seasonal changes of Yangtze river basin, and its amplitude of annual variation is 2.3cm. In addition, we compare the results with water resource statistics and hydrologic observation data to confirm the possibility of research of TWS variation of river basin using GRACE observation data, and also the satellite gravity data is of great help for the research on the movement and periodic changes of river basin.