Award: PLR-1202992

The primary goal for this project was to see if we could find a new, more convenient way to estimate how much atmospheric dust falls into the Arctic Ocean. There are some essential trace elements and pollutant heavy metals that are deposited to the Arctic Ocean from the atmosphere and we want to know what effects this will have on the Arctic Ocean ecosystem. Since we can't "be there" all of the time to measure the dust concentrations and dust chemistry year-round, we are using a "tracer" that also gets deposited to the Arctic Ocean from the atmosphere. That tracer is a radioactive isotope of berylium (7Be). It is deposited to the snow, ice, and open water of the Arctic along with the trace elements and heavy metals. But because 7Be has no biological function, it simply mixes into the upper ocean, integrating the last few months of atmospheric deposition while it undergoes radioactive decay. This input flux matches the radioactive decay rate which we can measure from a water column profile of 7Be. And we can collect aerosols over daily or weekly time scales (when the research ship is in the Arctic). Those aerosol samples are analyzed for trace elements and heavy metals in addition to 7Be. Then we simply multiply the ratio of any trace element to 7Be in the aerosol samples by the atmospheric flux of 7Be (calculated from the decay inventory in the water column profiles) to get the atmospheric flux for each trace element. We can then compare the atmospheric fluxes of trace elements and heavy metals to the fluxes coming in from rivers and glaciers to see how important they might be. Last Modified: 09/30/2014 Submitted by: William M Landing