Be-7 South Florida

In this project we are developing a new sampling method for extracting Beryllium-7 from seawater. Be-7 is a naturally occurring radionuclide that is formed in the atmosphere and deposited to the surface ocean via rainfall and aerosol deposition. It is useful as a tracer of processes in the upper ocean including aerosol deposition, mixing processes, and upwelling. Due to low concentrations, large volumes of seawater are required for Be-7 analysis. Be-7 is typically extracted from 400-700 L of seawater onto ferric hydroxide coated fibers (ferric hydroxide absorbs beryllium). Our aim is to simplify the sampling and extraction processes by using common drop-in filters and an in situ pumping system. This cruise will provide a side-by-side comparison of the old versus the new method in waters having a wide range of particle loads. We will sample along three transects from the coastal waters out to the open ocean off South Florida and the Florida Keys. The transects will provide information on Be-7 / particle absorption in the nearshore environment that may be applicable to other chemical species such as pollutants and trace metals.