Radon 222 from the ocean surface

The flux of $sup 222$Rn from the ocean surface has been measured by the accumulation method off the windward coast of the island of Hawaii. A figure of 74 +- 8 atoms m$sup -2$ s$sup -1$ was obtained, compared with a range of values from 11 to 116 atoms m$sup -2$ s$sup -1$ calculated from near-surface $sup 222$Rn concentration profiles in seawater obtained by other investigators. If these results are representative, the total oceanic contribution to $sup 222$Rn in the global atmosphere is only about 2% of all $sup 222$Rn exhaled from continents. Fluxes obtained by the accumulation method in shallow bay waters nearshore were intermediate between the very low value measured in the open ocean and the values obtained onshore.