HR: 1340h
AN: G43B-1205    [Abstracts]
TI: Accurate modeling of regional oceanic tides for detiding gravimeter data at southeastern Alaska
AU: * Inazu, D
EM: inazud@ism.ac.jp
AF: The Institute of Statistical Mathematics, 4-6-7 Minami-Azabu, Minato-ku, Tokyo, 106-8569, Japan
AU: Sato, T
EM: tsato@aob.geophys.tohoku.ac.jp
AF: Graduate School of Science, Tohoku University, 6-6 Aramaki-Aza-Aoba, Aoba-ku, Sendai, 980-8578, Japan
AU: Nakamura, K
EM: nakakazu@ism.ac.jp
AF: The Institute of Statistical Mathematics, 4-6-7 Minami-Azabu, Minato-ku, Tokyo, 106-8569, Japan
AU: Miura, S
EM: miura@aob.geophys.tohoku.ac.jp
AF: Graduate School of Science, Tohoku University, 6-6 Aramaki-Aza-Aoba, Aoba-ku, Sendai, 980-8578, Japan
AU: Higuchi, T
EM: higuchi@ism.ac.jp
AF: The Institute of Statistical Mathematics, 4-6-7 Minami-Azabu, Minato-ku, Tokyo, 106-8569, Japan
AU: Fujimoto, H
EM: fujimoto@aob.geophys.tohoku.ac.jp
AF: Graduate School of Science, Tohoku University, 6-6 Aramaki-Aza-Aoba, Aoba-ku, Sendai, 980-8578, Japan
AU: Larsen, C F
EM: chris.larsen@gi.alaska.edu
AF: Geophysical Institude, University of Alaska Fairbanks, 903 Koyukuk Dr, Fairbanks, AK 99775, United States
AB: We use a regional barotropic ocean model and investigate oceanic tides in southeastern Alaska characterized by complicated fjords to achieve the accurate prediction of the oceanic tides. The regional ocean model is forced by major 8 component tides of FES2004 (Lyard et al., 2006) at the computational boundaries. The simulated semidiurnal tides at coasts facing the open oceans are in good agreement with the observation. At the inside region of the Alaska Panhandle (AP), the simulated semidiurnal tides change in phase with the observation with their amplitude larger than the observational amplitude. Especially the amplitude of M2 tide is simulated by up to 40-50 cm larger than the observational value. The semidiurnal tides are amplified at the inside AP. Diurnal tides are realistically simulated at all coastal stations without amplification at the inside AP. The main fjord at the inside AP is assumed to be a one-dimensional channel. The period of the surface seiche of the channel is basically determined by the basin geometries, and is roughly estimated to be 9 hours. Therefore the sea level at the inside AP probably resonates with the semidiurnal tides. The gain of the semidiurnal tides seems strongly sensitive to uncertainties of the seabed topography of the inside AP.
DE: 1200 GEODESY AND GRAVITY
DE: 1217 Time variable gravity (7223, 7230)
DE: 3010 Gravity and isostasy (1218, 1222)
DE: 4217 Coastal processes
DE: 4560 Surface waves and tides (1222)
SC: Geodesy [G]
MN: 2007 Fall Meeting