HR: 0800h
AN: OS21C-1273    [Abstracts]
TI: Seasonal Characteristics of Circulation in the Southeastern Tropical Indian Ocean
AU: * Qu, T
EM: tangdong@hawaii.edu
AF: IPRC/SOEST, University of Hawaii, 2525 Correa Road, Honolulu, HI 96822 United States
AU: Meyers, G
EM: Gary.Meyers@csiro.au
AF: CSIRO Marine Research, GPO Box 1538, Hobart, TS 7001 Australia
AB: The circulation in the southeastern tropical Indian Ocean is studied using historical temperature and salinity data. A southward shift of the subtropical gyre at increasing depth dominates the structure of the annual mean circulation. Near the southern Indonesian coast, the westward South Equatorial Current (SEC) is at the sea surface and strongest near 10ø-11øS, reflecting strong influence of the Indonesian Throughflow (ITF). In latitudes 13ø-25øS the SEC is a subsurface flow and its velocity core deepens toward the south, falling below 500 m at 25øS. The Eastern Gyral Current (EGC) is a surface flow overlying the SEC, associated with the meridional gradients of near-surface temperature and salinity. The ITF supplies water to the SEC mainly in the upper 400 m, and below that depth the flow is reversed along the coast of Sumatra and Java. Monsoon-winds strongly force the annual variation in circulation. Dynamic height at the sea surface has a maximum amplitude at 10ø-13øS, and the maximum at deeper levels is located further south. Annual variation is also strong in the coastal wave guides, but is mainly confined to the near-surface layer. Although the South Java Current at the sea surface is not well resolved in the present dataset, semiannual variation is markedly evident at depth and tends to extend much deeper than annual variation along the coast of Sumatra and Java.
DE: 4504 Air/sea interactions (0312)
DE: 4516 Eastern boundary currents
DE: 4532 General circulation
DE: 4572 Upper ocean processes
SC: Ocean Sciences [OS]
MN: 2004 AGU Fall Meeting