The remote sensing techniques have been used for better understandings of the coastal sea aspects around the Beppu Bay.
One of the Kuroshio branch current comes up to the Bungo Channel and enters the bay in winter. Then, it makes a coastal front between the mouth and the interior of the bay, while small scale eddies can be seen inside the front.
A cold water flow from the Suo Sea possibly comes down along the Kunisaki Peninsula for the period from autumn to spring. The cold water would then come into the bay and cause a left swirling flow. For further observation, long period variations of the surface water temperature and salinity around the bay have been analized by a stochastic technique and discussed qualitatively.
