Vertical profiles and inventories of anthropogenic radionuclides in sea water

Distribution in surface seawater specifically near Japan sea and the North-West Pacific ocean and in particular distribution of vertical profiles and inventories of such artificial radionuclide as cesium 137, strontium 90, plutonium isotopes (239 and 240), americium 241, and tritium are briefly explained using data based on IAEA-MEL research on worldwide marine radioactivity started in 1995 to which the present author participated. The concentration of strontium 90, cesium 137, and plutonium isotopes are graphically demonstrated as function of depth 0∼4,000 m, and inventory as integrated radioactivity for example 3.4 kBq / m² unit surface sea area is given for cesium 137. (S. Ohno)