A request is made to fund additional and back-up instrumentation for the R/V Cape Hatteras, a 136-ft long research vessel owned by the National Science Foundation and operated by the Duke/UNC Oceanographic Consortium as part of the University-National Oceanographic Laboratory System (UNOLS) research fleet. Two items were submitted for review. In order of priority they were: 1) Chelsea Fluorometer 2) ROV
Broader Impacts: The principal impact of the present proposal is under criterion two, providing infrastructure support for scientists to use the vessel and its shared-use instrumentation in support of their NSF-funded oceanographic research projects (which individually undergo separate review by the relevant research program of NSF). The acquisition, maintenance and operation of shared-use instrumentation allows NSF-funded researchers from any US university or lab access to working, calibrated instruments for their research, reducing the cost of that research, and expanding the base of potential researchers.
This award funded a replacement Aquatracka II profiling fluorometer. The Aquatracka fluorometer allows the Cape Hatteras to continue her capability to sample the water column from the surface to 6,000 meters without changing out instrumentation as well as providing a redundant sensor for chlorophyll a determination. Profiling the water column is a regular operation at almost every station on a research cruise. With the information about the salinity, temperature, density, chlorophyll a and particle distribution with depth, scientists can determine their water sampling strategy and make inter-station comparisons. One of the most used sensors on the R/V Cape Hatteras is the Aquatracka fluorometer, which is used to measure chlorophyll a as an indicator of algal biomass. For chlorophyll a determinations, the Aquatracka measures fluorescence by chlorophyll after it has been excited by illumination. The excitation wavelength band for the new Aquatracka II is 430 – 105 nanometers and the emission band is 685 – 30 nanometers. The instrument can detect chlorophyll in the concentration range of 0.01 – 100 ug/l. It utilizes a Xenon lamp for its light source and a photodiode for fluorescence detection. Its depth limit is 6,000 meters and has a temperature range of -2 to +320C. The new Aquatracka II fluorometer has become the vesselâ€™s primary instrument for chlorophyll a determination. With the acquisition of this new fluorometer, the shipâ€™s CTD/Carousel has redundant sensors for all of its optical, chemical, and physical instrumentation that have the same depth limit.