Eddy transport of anthropogenic chemicals in the lee of Hawai’i
This study will test the hypothesis that eddies do not entrain land-based anthropogenic chemicals, but instead force them to flow around the eddy. Research has previously been done on particle export in eddies and the influence of eddies on biological processes and productivity, finding that particle export and biological productivity are higher in eddies due to upwelling (Maiti et al. 2008) (Bidigare et al. 2003). Other studies have been done on eddy transport of anthropogenic chemicals, but they have been done using gasses, such as CFC-11, which would not be expected to react in the same fashion to surface water movements (Lachkar et al. 2007). Thus this study will fill a gap in the understanding of eddy chemical transport.
Since eddies are a near-constant occurrence in the lee of the Hawaiian Islands, between 156°W-160°W and 19°N-21°N (Yoshida et al. 2010), it is likely that eddies have some effect on the transport of land-based anthropogenic chemicals that originate from the habited islands. In order to locate such an eddy before taking in-situ measurements, satellite-measured sea surface temperature will be tracked online (Bidigaire et al. 2003). On board the R/V Thompson, the edges of the eddy will be located using sea surface temperature measurements (Bigidare et al. 2003) by using the water flow through system. In-situ measurements will be collected from the 26th of December 2010 to the 4th of January 2011 and subsequent analyzing will occur during the month of January. In order to study the anthropogenic chemicals within and surrounding the eddy, water samples will be taken from ~5 m depth, collected at multiple points near the edges and center of the eddy. To analyze the chemicals, water samples will be pre-filtered and acidified, processed using solid phase extraction, elution, and run on a Gas Chromatograph-Mass Spectrometer. The data gathered during this study will help to expand our knowledge of the role that eddies play in affecting anthropogenic chemical transport.