Dr Raymond Najjar

Dr Raymond Najjar
Pennsylvania State University
Department of Meteorology
522 Walker Building
University Park
Fields of interest
I work on a few areas involving the interaction of the oceans with the climate system: (1) marine carbon, oxygen and nutrient cycling, (2) the impact of climate change on estuaries, (3) air-sea fluxes of radiatively important gases.
Description of scientific projects
(1) Calcium carbonate cycling in the ocean. This is a JGOFS project involving several institutions, funded by NSF. The main goal is to put better constraints on global rates of calcium carbonate production, export, dissolution and burial. We are doing this through the analysis of a variety of data sets and through modeling. (2) Dimethyl sulfide (DMS) cycling in the mixed layer of the ocean. This an NSF Biocomplexity project involving several institutions. The main goal is to understand and be able to model the dominant processes of DMS production and consumption in the mixed layer. Fieldwork is in the Sargasso Sea and Antarctica. (3) Modeling interannual variability in air-sea oxygen and carbon dioxide fluxes. This is a joint project with Mick Follows of MIT, funded by NOAA. We are using a variety of oceanographic data sets and models to understand the processes governing interannual variability in these fluxes. (4) Impact of climate change on mid-Atlantic coastal waters. This is a multi-institutional, EPA-funded project whose main goal is to provide information to stakeholders in the mid-Atlantic region about climate change and land use. My role is to use climate models to project possible changes to mid-Atlantic coastal waters, including the impact of sea-level rise and changing streamflow on the salinity of mid-Atlantic estuaries. (5) Carbon budget of the continental shelf of the Eastern U.S. This is a multi-institutional, NASA-funded project to constrain this budget using models and existing observations. My role is to analyze the oxygen distribution in order to constrain rates of organic matter cycling. (6) Nutrient cycling in the subtropical Atlantic. This is a NASA-funded project with Susanne Neuer (Arizona State University). We are analyzing time-series data from the eastern and western subtropical North Atlantic to constrain rates of export production and remineralization in these areas.