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  1. Maria Villa Alfageme on March 6, 2021 at 4:17 pm

    Dear John,
    Thank you for this contribution! My question is a super super basic one, because I am not so familiarized with Pacific as I am with Atlantic Ocean. What I see from your poster is that 137Cs eventually enters into the Arctic from the Bearing strait, but not following “a straight line”, but a detour passing near North America coast, forced by the Kuroshio current. Is that correct? Or water masses form Kurushio current divides in two branches? One following North America East Coast and the second one directly to Bearing Strait?

    Thank you!

    • John Smith on March 9, 2021 at 10:38 am

      Hi Maria,

      Thanks for your question.

      The Fukushima radionuclide signal is transported eastward from Japan across the Pacific Ocean in the North Pacific and Subarctic Currents which bifurcate on approaching North America with one branch turning south as the California Current and the other turning north as the Alaska Current. The Alaska Current flows northward across Line P and forms the eastern boundary of the Alaska Gyre. At its northern extremity the Alaska Current evolves into the Alaskan Stream which flows westward at the upper edge of the Alaska Gyre carrying a significant inventory of Fukushima radio-cesium. Part of the Alaskan Stream passes into the Bering Sea carrying the Fukushima contamination and from there it flows through the Bering strait into the Arctic Ocean. In the lower right hand panel, you can see that the Fukushima Cs-137 levels are elevated around the edges of the Alaska Gyre, but the signal has not yet significantly entered the core of the gyre.