POLEWARD: A drifter experiment to quantify the poleward transport, transformation and spreading of oceanic properties

We propose to observe, describe and quantify the oceanic transport poleward and the transformation, spreading and mixing rates of water parcels in the Nordic and Barents Seas by monitoring the motion of the water parcels. In the process we will be quantif ying the mechanisms transforming the warm surface waters to dense waters, a most crucial of processes associated with the thermohaline circulation (THC). We apply modern, expendable technology, reporting in real time via satellite transmission, and use so phisticated statistical and numerical methods in our analysis. We aim to educate two PhD students, through the Universities of Oslo and Bergen, and with advisors from the Norwegian Polar Institute and the Norwegian Meteorological Institute as well. We wi ll test the idea that lateral heat transport by eddies is an important dynamic of the Norwegian Atlantic Current, the warm surface limb of the THC. We will deploy 120 satellite-tracked surface drifters into the core of the current, at four different sites . We will track the drifters? trajectories, and analyze them using state-of-the-art statistical measures. The work could greatly improve our understanding of the THC and of its representation in climate models. If it indeed turns out that the cooling is m ediated by deformation scale eddies, this study will be invaluable. Such eddies, with scales of 5-10 km, are barely resolved by today?s operational models and completely unresolved by ocean models in coupled simulations. Parameterizing such eddy-induced c ooling will not be possible without direct Lagrangian observations. The results will also yield an unparalleled view of the surface circulation and the spreading of water properties such as heat, nutrients and pollutants in the Nordic Seas, in the interi or of the Barents Sea, at in the recirculation region of the Fram Strait. These are all important regions for fishery and offshore industry in Norway, and therefore potential sites for environmental disasters.