The Russian-Swedish tundra radioecology expedition 1994

The expedition investigated the ecology of the anthropogenic radio nuclides 137Cs, 90Sr, and 239,240Pu in the Northern Sea to explain the origin from different sources. It had been shown from an earlier expedition that the levels of 137Cs are higher in the central Arctic Ocean than further south in Barents Sea. The question was if this was due to inflow from the Atlantic or is due to other origin. The expedition also examined the outflow of 90Sr from the rivers along the Siberian coast in order to investigate if the permafrost enhances the run-off of radionuclides from tundra. Study of anthropogenic radionuclides in the mixing zone between fresh and salt water at the different river systems along the Siberian coast was of particular interest. Some of the results from the expedition are presented in the present paper. 3 refs., 3 figs., 3 tabs