Affiliations: Faculty of Fisheries, Kagoshima University,
Shimo-arata 4-50-20, Kagoshima City,Kagoshima Pref., 890-0056, Japan. E-mail:
hosotani@mail.goo.ne.jp | Graduate School of Science and Technology, Nagasaki
University, 1-14 Bunkyo-machi Nagasaki-shi, 852-8521, Japan
Abstract: Kagoshima Bay is an enclosed bay that has the tendency to undergo
eutrophication, and a very important site to describe the behavior of open
seawater intrusion. According to the results of the satellite SST (Sea Surface
Temperature) image analysis or numerical simulation focused on the warm water
intrusion into the bay in winter, a warm water mass originates in the
meandering Kuroshio Current and reaches the mouth of the bay making the density
flow to act like a semi-geostrophic current that is influenced by the Coriolis
effect. However, there is still no information on the oceanic intruding flow
during the summer, where it is accompanied by thermal stratification. In this
research, satellite remote sensing and numerical simulation were employed to
investigate the oceanic water intrusion into Kagoshima Bay during the summer
season by using satellite chl-a (chlorophyll-a) images instead of SST. As a
result, the distribution of the low-concentration chl-a with the oceanic water
intrusion was found to be similar to the intrusion that occurs during the
winter season. Furthermore, the numerical simulation was performed under the
simple assumption that the thickness of the warm water mass that reaches the
southern coast of Kyushu also shows the same tendency as in the winter season.
Although the characteristics, such as the intruding speed or intruding pattern,
are similar in winter, some features such as the generation of the inflow from
the middle layer, showed a different tendency.
Keywords: Kagoshima Bay, MODIS/Aqua, Numerical simulation, Oceanic water intrusion, Chlorophyll-a, Sea Surface Temperature
