Prominent circulation features in the Japan Sea include the Tshushima Current, the Tsugaru Current, the Liman Current, the North Korea Current and the Mid-Japan Sea or Maritime Province Current. Water masses found there include Japan Sea Middle Water (or Intermediate Water) and Japan Sea Proper Water.
The Japan Sea is a meeting place for warm currents from the south and cold currents from the north, with the confluence being the Polar Front. See Tomczak and Godfrey (1994) and Zenkevitch (1963).
The Java Sea was formed when two large river systems, now forming shallow channels in the shallow sea floor, were drowned out at the end of the last ice age. The circulation and hydrography are determined by the annual cycle of monsoon winds, with currents flowing westward from June to August and eastward during the rest of the year. During this latter period a tongue of high salinity water from the South China Sea pushes salinity values of 32 as far east as 112 E. See Tomczak and Godfrey (1994).