The goal of this research is to better understand how changes in global emissions and climate are affecting the distribution, lifetime, and bioavailability of selected persistent organic pollutants (POPs) in the Arctic Ocean. POPs travel globally in air and water, are often highly bioaccumulative, and have the ability to cycle among environmental media enabling long-range transport to remote regions such as the Arctic. The investigators will use a modeling approach to provide insight into the relative importance of changing primary anthropogenic emissions and oceanic biogeochemical processes in controlling the fate and lifetime of POPs in the Arctic Ocean. The research will focus on two classes of compounds (polyfluorinated compounds - PFCs - and polychlorinated biphenyls - PCBs) with contrasting physical and chemical properties affecting behavior and reactivity in the atmosphere and ocean. The investigators will also collect new data on depth profiles of PCBs and two PFCs - perfluorooctane sulfonate (PFOS) and perfluorooctanate (PFOA) - in the Arctic Ocean.