Subfilter scale fluxes in the marine surface layer: Results from the Ocean Horizontal Array Turbulence Study (OHATS)

We have presented results from a new field campaign, the Ocean Horizontal Array Turbulence Study (OHATS), designed to obtain measurements of subfilter-scale variables in the marine surface layer. A first look at the data shows both similarities and differences with a comparable experiment carried out over a rough land surface (the Horizontal Array Turbulence Study). For example, the results for the vertical component of SFS scalar flux show a clear wave signature while the variation of the normal components of the SFS momentum flux τ_ii are similar over land and water. The bulk of the OHATS observations are obtained under low wind conditions in the presence of fast moving swell, and thus the interactions between atmospheric turbulence and the wave field needs to be considered. The impact of swell and more generally the underlying wave field on SFS variables and their modeling are topics for future investigation. We plan to split the wind fields into turbulent and wavy contributions using the algorithm described by Hristov et al. (1998) in order to identify their separate contributions to the SFS fluxes and energy transfer. Acknowledgments: We thank Tihomir Hristov and Edward Patton for useful discussions. This work is supported by the Office of Naval Research and the National Science Foundation. NCAR is sponsored by the National Science Foundation.