Tomographic measurements of the Kuroshio Extension meander and its associated eddies
Gang Yuan, Iwao Nakano, Hidetoshi Fujimori, Toshiaki Nakamura, Takashi Kamoshida, and Akio Kaya
International Pccacific Research Center, Honolulu, Hawaii.
Japan Marine Science and Technology Center, Yokosuka, Japan.
Oki Electric Industry Co., Ltd., Tokyo, Japan.
A 1000-km scale three-dimensional acoustic tomography experiment has been conducted in the Kuroshio Extension region from July to September 1997. The inverse analysis of acoustic travel time data provides estimates of the time evolution of the three-dimensional temperature field over a 1000-km × 1000-km domain. The three-dimensional temperature fields show the energetic meander of the Kuroshio Extension with high time resolution. Mesoscale eddies associated with the meander with horizontal scale greater than 200-km are resolved in the tomographic inversion. These results are consistent with other measurements such as ADCP, XCTD and TOPEX/POSIEDON satellite altimetry. Variable oceanic structures in a 1000-km domain, which are difficult targets for the conventional point measurement techniques, can be measured well by ocean acoustic tomography with a real-time data telemetry.
