Abstract:

One widely used parameterization for modeling upper ocean oil dispersion is the K-profile parameterization (KPP) [Large et al., 1994], which models the eddy viscosity and eddy diffusivity in the format of a one-dimensional vertical profile. The standard KPP model was developed for pure wind-induced shear turbulence and the effect of Langmuir circulations was not included. The current dataset contains profiles of eddy diffusivities for vertical diffusion of oil plumes in ocean mixed layer with Langmuir circulations in presence. The profiles are based on statistical analysis of a series of large eddy simulations, covering various turbulent Langmuir numbers (ranging from 0.36 to 0.61) and oil droplet diameters (ranging from 88 microns to 354 microns). The current dataset provides useful information for assessing existing KPP models and developing new KPP models with the effect Langmuir circulations properly parameterized. More details of the simulations and data analysis can be found in the paper "Oil plumes and dispersion in Langmuir, upper-ocean turbulence: large-eddy simulations and K-profile parameterization" (Journal of Geophysical Research, DOI: 10.1002/2014JC010542).

Suggested Citation:

Di Yang, Bicheng Chen, Marcelo Chamecki, and Charles Meneveau. 2015. Vertical eddy diffusivity for oil dispersion in upper ocean Langmuir turbulence. Distributed by: GRIIDC, Harte Research Institute, Texas A&M University–Corpus Christi. doi:10.7266/N76M34R4

Publications:

Yang, D., Chen, B., Chamecki, M., & Meneveau, C. (2015). Oil plumes and dispersion in Langmuir, upper-ocean turbulence: Large-eddy simulations and K-profile parameterization. Journal of Geophysical Research: Oceans, 120(7), 4729–4759. doi:10.1002/2014jc010542

Purpose:

To help improve the KPP model performance under Langmuir turbulence condition.

Data Parameters and Units:

******************************************* Data files are ready to be opened by Tecplot (a visualization tool for fluid dynamics). Visual illustrations of this dataset are provided in the folder "plot". ***************************************************** * Physical parameters for the large-eddy simulation * ***************************************************** Domain size of the LES: 1000m x 1000m x 150m Initial mixed layer depth: z_i = 100 m Wind direction: x-direction Wind friction velocity: u* = 0.0125 m/s Wave propagation direction: x-direction Sea water density: 1031.0 kg/m^3 Sea water viscosity: 1.08E-3 kg/(m s) Oil releasing rate: 1 kg/s Oil releasing depth: z = -150 m Oil density: 859.9 kg/m^3 Oil droplet diameters: d = 88, 125, 177, 250, and 354 microns ************************ * For case La_t = 0.36 * ************************ Wavelength: 120 m Wave amplitude: 1.6 m Stokes drift velocity: Us = 0.096 m/s Turbulent Langmuir number: La_t = sqrt(u*/Us) = 0.36 ************************ * For case La_t = 0.43 * ************************ Wavelength: 60 m Wave amplitude: 0.8 m Stokes drift velocity: Us = 0.068 m/s Turbulent Langmuir number: La_t = sqrt(u*/Us) = 0.43 ************************ * For case La_t = 0.51 * ************************ Wavelength: 30 m Wave amplitude: 0.4 m Stokes drift velocity: Us = 0.048 m/s Turbulent Langmuir number: La_t = sqrt(u*/Us) = 0.51 ************************ * For case La_t = 0.61 * ************************ Wavelength: 15 m Wave amplitude: 0.2 m Stokes drift velocity: Us = 0.034 m/s Turbulent Langmuir number: La_t = sqrt(u*/Us) = 0.61 *********************************************************************** In Vertical_eddy_diffusivity.dat *********************************************************************** Definition of variables: z_normalized_by_zm: vertial coordinate "z" normalized by initial mixed layer depth "zi" Kcz_normalized_by_ustar_zi: vertical eddy diffusivity "Kcz" normalized by wind friction velocity "u*" and initial mixed layer depth "zi" The dataset includes four different La_t flow conditions. For each flow condition, results for five different oil droplet diameters are included. The ID of each case is indicated in the "zone" names in the data file.

Individual Files: