What Lies Beneath? Using Remote Sensing to Determine Currents, Features, and Turbulence Below the Surface

Abstract

Remotely sensed images of the littoral ocean can be used to estimate wave breaking,currents, and features that protrude above the water. However, despite tremendousprogress interpreting the backscattered signals, these techniques have not yet been used todetermine what lies beneath the surface. Interior currents, important to Navy SEALS, aswell as scientists and engineers, may be stronger and opposite those on the surface.Similarly, there may be quiescent areas under a fast moving layer of surface waterdetected by a remote device. Patterns of wave breaking may allow detection ofunderlying features, including crater-like holes, sandbars, obstacles, and other hazards tooperations. Here, the objective is to determine what lies beneath remotely sensed imagesof the sea surface in littoral areas. The approach is to combine images of the sea surfacewith in-situ observations spanning the water column and with numerical models to relateremote sensing of the surface to the currents and features beneath. Although the goal ofrelating surface to interior processes is challenging, pilot work suggests significantprogress can be made with focused observational and numerical studies. Combiningremote and in-situ observations also will enable investigation of recently discovered,highly energetic, small-scale (< 5 m) motions in the littoral ocean. These ~nearshoremesoscale~ motions may be important to include in models. Moreover, they provide aunique opportunity to investigate the simultaneous nonlinear transfers of energy fromsmall to large scales (2D turbulence) and from large to small scales (3D) where energy isdissipated, with applications to a wide range of turbulent processes. Anticipated outcomesinclude obtaining better information from remote sensing for military operations, anincreased understanding of the fundamental physics of littoral process and turbulence,higher spatial- and temporal-resolution numerical models, and the potential to discovernew phenomena.

Document Details

Document Type
DoD Grant Award
Publication Date
Sep 23, 2016
Source ID
N000141612822

Entities

People

  • Stephen Elgar

Organizations

  • Office of Naval Research
  • United States Navy
  • Woods Hole Oceanographic Institution

Tags

Readers

  • Coastal Oceanography
  • Military Engineering.
  • Research Science/Academic Research