The award will examine the salinity history of the North Atlantic subtropical gyre since the last glacial period. Specifically, it will examine magnesium and calcite isotopic records from planktonic foraminifera in cores from the Bahamas Islands in an effort to assess the timing and magnitude of Atlantic Ocean overturning circulation on orbital and millennial time scales. The implication from previous research in this region is that large changes in the hydrological cycle of the Atlantic occur on these time scales.
The results of this research will be important for understanding how the hydrological cycle has changed in the past in response to natural forcing and how the changes feed back into other parts of the climate system. The results may lead to greater understand of the response of the Earth's hydrological cycle to current and future greenhouse forcing and how future changes in ocean hydrography may alter circulation patterns and climate. Quantitative estimates of past ocean salinity will be of use to ocean and climate modelers as a test of the sensitivity of their models to past climate forcing.
This project will fund high school students who will help process forams for taxonomic and chemical analyses. As in the past, students who have worked in the researcher's laboratory will have the opportunity to present the results of their scientific experiments as part of local and regional science fairs.
