The proposed study will develop a novel mathematical approach for better understanding contributions of correlations at long periods to the behavior and predictability of the path and dispersion of ocean waters. Methods of non-equilibrium statistical mechanics and probabilistic statistics will be applied to obtain a hierarchy of stochastic Lagrangian models of varying complexity. Models will be verified using a first-exit time concept and probability weighted moment techniques. The approach will utilize shorter observation series than traditional methods used in oceanography, be robust to the effects of noise in the measurements, and account for inhomogeneity of wave-eddy oceanic fields. The effectiveness of the mathematical technique will be illustrated by estimating Lagrangian statistics and ocean currents using subsurface float observations from the North Pacific and North Atlantic Oceans.
Robust mathematical techniques will be developed for the analysis of the motion of floats and drifters in the ocean. The higher accuracy of these new techniques will improve the description of mean velocity fields as well as those for the path and dispersal of ocean waters. Computational efficiencies may allow more efficient assimilation of Lagrangian data into numerical ocean models. Results will allow a better understanding and description of the exchange of ocean waters between various geographic regions such as the continental margin and the deep ocean or between Subtropical and Subarctic ocean gyres. Results will contribute to related problems such as estimating the carbon export from the continental margin to the deep sea, the sequestration of carbon dioxide in Subtropical regions, and the dispersal of pollutants in the ocean.
Broader Impacts: The proposal will involve graduate students and young scientists including women from the Naval Postgraduate School (Monterey, CA), University of Southern California (Los Angeles, CA) as well as other Monterey area institutions (Monterey Bay Aquarium Research Institute, Moss Landing Marine Laboratories, and Pacific Fisheries Environmental Laboratory). Current velocity and diffusivity will be used to forecast biological productivity along the Central California Coast. In collaboration with researchers from the Southampton (U.K.) Oceanographic Center, the methods developed will be applied to ARGO float observations collected in the North Atlantic in order to reconstruct and understand variability of mid depth ocean circulation. This will contribute the ARGO program, the Global Ocean and Climate Observing Systems. Activities will include open scientific communications as well as presentations to the broader community. To assure the dissemination of the research to the broadest possible scientific and public audience, project results will be published in the peer-reviewed scientific literature in a timely manner; and presented at scientific conferences and workshops in the United States and abroad. Interim working papers and graphical representations will be posted on web- sites in the *.edu domain. Research results will be converted into teaching aids for graduate and undergraduate courses in easy-to-use formats, such as visual animations and Microsoft PowerPoint presentations and will also be available via Internet for policy-makers and the public at large. These educational materials may also be used for a graduate-level marine science textbook on problems of determining circulation properties using Lagrangian floats and drifters.
