Intercomparison of Bulk Aerodynamic Algorithms for the Computation of Sea Surface Fluxes Using TOGA COARE and TAO Data

Abstract A bulk aerodynamic algorithm is developed for all stability conditions for the computation of ocean surface fluxes. It provides roughness lengths of wind, humidity, and temperature for a wind speed range from 0 to 18 m s−1: zo = 0.013u2∗/g + 0.11ν/u∗ and ln(zo/zot) = ln(zo/zoq) = 2.67Re1/4∗ − 2.57 as derived using the Tropical Oceans Global Atmosphere (TOGA) Coupled Ocean–Atmosphere Response Experiment (COARE) data constrained by other observations under high wind conditions. Using the TOGA COARE ship data and the multiyear hourly TOGA Tropical Atmosphere–Ocean moored buoy data, intercomparison of six different algorithms, which are widely used in research, operational forecasting, and data reanalysis, shows that algorithms differ significantly in heat and momentum fluxes under both very weak and very strong wind conditions, but agree with each other under moderate wind conditions. Algorithms agree better for wind stress than for heat fluxes. Based on past observations, probable deficiencies in r...

[1]  Patrice G. Mestayer,et al.  Two Major Experiments in the Humidity Exchange over the Sea (HEXOS) Program , 1990 .

[2]  E. B. Kraus,et al.  Atmosphere-Ocean Interaction , 1972 .

[3]  The Origin of Flux Adjustments in a Coupled Model , 1997 .

[4]  Martin W. Johnson,et al.  The oceans : their physics, chemistry, and general biology , 1943 .

[5]  M. Mcphaden,et al.  Enhancement of Tropical Ocean Evaporation and Sensible Heat Flux by Atmospheric Mesoscale Systems , 1996 .

[6]  Evidence of systematic biases in ocean surface heat fluxes simulated by AGCMs , 1995 .

[7]  P. Webster,et al.  TOGA COARE: The Coupled Ocean-Atmosphere Response Experiment. , 1992 .

[8]  W. Liu,et al.  Bulk Parameterization of Air-Sea Exchanges of Heat and Water Vapor Including the Molecular Constraints at the Interface , 1979 .

[9]  E. F. Bradley,et al.  Bulk parameterization of air‐sea fluxes for Tropical Ocean‐Global Atmosphere Coupled‐Ocean Atmosphere Response Experiment , 1996 .

[10]  A. Holtslag,et al.  A High Resolution Air Mass Transformation Model for Short-Range Weather Forecasting , 1990 .

[11]  W. Tao,et al.  The Impact of Ocean Surface Fluxes on a TOGA COARE Convective System , 1996 .

[12]  Simulation Errors Associated with the Neglect of Oceanic Salinity in an Atmospheric GCM , 1997 .

[13]  A. Holtslag,et al.  Applied Modeling of the Nighttime Surface Energy Balance over Land , 1988 .

[14]  E. F. Bradley,et al.  Measurements of sensible and latent heat flux in the western equatorial Pacific Ocean , 1991 .

[15]  A. Dyer.  A review of flux-profile relationships , 1974 .

[16]  K. Katsaros,et al.  HEXOS—Humidity Exchange Over the Sea A Program for Research on Water-Vapor and Droplet Fluxes from Sea of Air at Moderate to High Wind Speeds , 1987 .

[17]  R. Dickinson,et al.  Effect of Surface Sublayer on Surface Skin Temperature and Fluxes , 1998 .

[18]  A. Yaglom,et al.  Mean fields and fluctuation moments in unstably stratified turbulent boundary layers , 1990, Journal of Fluid Mechanics.

[19]  S. Schubert,et al.  Climatology of the Simulated Great Plains Low-Level Jet and Its Contribution to the Continental Moisture Budget of the United States , 1995 .

[20]  W. A. Oost,et al.  Air‐sea exchange of water vapor and sensible heat: The Humidity Exchange Over the Sea (HEXOS) results , 1996 .

[21]  D. E. Harrison,et al.  Scales of Variability in the Equatorial Pacific Inferred form Tropical Atmosphere-Ocean Buoy Array , 1996 .

[22]  Stuart D. Smith.  Coefficients for sea surface wind stress, heat flux, and wind profiles as a function of wind speed and temperature , 1988 .

[23]  T. Palmer,et al.  The Sensitivity of the ECMWF Model to the Parameterization of Evaporation from the Tropical Oceans , 1992 .

[24]  Michael J. McPhaden,et al.  TOGA-TAO and the 1991–93 El Niño Southern Oscillation Event , 1993 .

[25]  W. Large,et al.  Open Ocean Momentum Flux Measurements in Moderate to Strong Winds , 1981 .

[26]  A. Beljaars.  The parametrization of surface fluxes in large-scale models under free convection , 1995 .

[27]  J. Kondo,et al.  Air-sea bulk transfer coefficients in diabatic conditions , 1975 .

[28]  H. Panofsky,et al.  Atmospheric Turbulence: Models and Methods for Engineering Applications , 1984 .

[29]  K. Emanuel.  Sensitivity of Tropical Cyclones to Surface Exchange Coefficients and a Revised Steady-State Model incorporating Eye Dynamics , 1995 .

[30]  R. H. Clarke,et al.  Observational studies in the atmospheric boundary layer , 1970 .

[31]  L. J. Mangum,et al.  TOGA-TAO: A Moored Array for Real-time Measurements in the Tropical Pacific Ocean , 1991 .

[32]  J. Curry,et al.  Evaluation of turbulent fluxes at the ocean surface using surface renewal theory , 1996 .