HR: 1340h
AN: G33B-0042 [Abstracts]
TI: GRACE Observed Ocean Tides Underneath Large Antarctic Ice Shelves
AU: * Shum, C
EM: ckshum@osu.edu
AF: Lab. for Space Geodesy & Remote Sensing, Ohio State University, 275 Mendenhall
125 S Oval Mall, Columbus, OH 43210
United States
AU: Han, S
EM: han.104@osu.edu
AF: Geological Sciences, Ohio State University, 275 Mendenhall
125 S Oval Mall, Columbus, OH 43210
United States
AU: Matsumoto, K
EM: matumoto@miz.nao.ac.jp
AF: Mizusawa Astrogeodynamic Observatory, National Astronomical Observatory of Japan, 2-12, Hoshigaoka,
Mizusawa, Iwate, 023-0861
Japan
AB:
By processing the GRACE inter-satellite Ka-band range-rate tracking data and estimating the temporal gravity fields
regionally over Antarctica with a 5-day temporal sampling, we observe M2 and S2 ocean tides underneath Antarctica's large
ice-shelves, including Fichner-Ronne and Larsen Ice Shelves. Based on the predicted aliased tidal periods, we extracted the
M2 and S2 signals from the time-series of 5-daily mean GRACE observed regional gravity estimates. GRACE observations agree
well with the predicted tides from the FES2004 and CATS02.01 models after smoothing the models to a commensurate spatial
resolution to compare with GRACE. In general, the GRACE and the models agreed within 10~20% in amplitude and 20 degrees
in phase for both M2 and S2. Our results suggest the GRACE provides valuable observations of ocean tides, with a spatial
resolution of up to 300 km, especially over the remote area lacking of quality observations, such as the Antarctica
ice-shelves.
DE: 1240 Satellite geodesy: results (6929, 7215, 7230, 7240)
DE: 1827 Glaciology (0736, 0776, 1863)
SC: Geodesy [G]
MN: Fall Meeting 2005