This research is concerned with the fundamental understanding and modeling of complex physical, acoustical and biogeochemical oceanic dynamics and processes. New mathematical models and computational methods are created, developed and utilized for: (i) ocean predictions and dynamical diagnostics, (ii) data assimilation and data-model comparisons, and, (iii) optimization and control of autonomous ocean observation systems. The regional dynamics involves interactions of sub-mesoscale and mesoscale ocean processes in the littoral as well as effects from large-scale processes in ocean basins. Such interactions and feedbacks with scales smaller and larger than the mesoscale need be better quantified. The technical approach is rooted in the comparison and optimal combination of measurements and models via nonlinear data assimilation (DA), including the development of adaptive modeling and adaptive sampling schemes based on Error Subspace Statistical Estimation. Our research group is updating and renewing our previous approaches and computational schemes and systems. We will keep and modernize the strengths of our methods and codes, but we will also progressively utilize other ocean dynamical models, or parts thereof, and explore novel numerical systems.

The research topics specific to this effort include: (i) three-dimensional (3D) acoustic modeling coupled with high-resolution 4D physics modeling; (ii) ocean modeling incubator: structured and unstructured grids; investigations and evaluations of the next generation of numerical schemes for physical, acoustical and biological dynamics; (iii) interactions of internal tides/waves and mixing processes with mesoscale dynamics, their high-resolution modeling and multi-scale diagnostics; (iv) Lagrangian coherent structures and ocean features: their prediction, dynamics and assimilation; (v) nonlinear DA and adaptive DA, including (super)-tidal constraints and assimilation; and, (vi) use of several ocean models, model uncertainty estimation, and multi-model fusion and DA.

General objectives are to: (i) analyze and study regional physical and acoustical-physical-biogeochemical dynamics; (ii) incubate and develop new numerical modeling systems, including next generation ocean physics, 3D acoustics and Lagrangian coherent structures predictions; (iii) update existing and create new nonlinear and adaptive assimilation schemes and systems, including parameter estimation; (iv) evolve concepts and determine methodologies for regional adaptive modeling and adaptive sampling with the intent to increase predictive capabilities; (v) quantify regional predictabilities and improve probability and uncertainty modeling; and, (vi) utilize several ocean models, estimate their uncertainty statistics and fuse their estimates.

An emphasis is on acoustical-physical interactions in 3D space and time, and on acoustical-biogeochemical-physical estimation. The investigations are generic but the focus is on specific ocean regions: the Mid-Atlantic Bight (MAB) and Shelfbreak Front region, the Chinese-Taiwanese Seas and Philippine Seas; the Monterey Bay and California Current System (CCS) region, the Massachusetts Bay/New England shelf region, and the Mediterranean and Black Seas. Several of these regions have been or are investigated under other collaborative efforts, some of which sponsored by the Office of Naval Research.