• Banner, M., W. Chen, E. Walsh, J. Jensen, S. Lee, and C. Fandry, 1999: The Southern Ocean Wave Experiment. Part I: Overview and mean results. J. Phys. Oceanogr., 29 , 21302144.

    • Search Google Scholar
    • Export Citation
  • Bidlot, J., B. Hansen, and P. Janssen, 1999: Ocean waves project memorandum. ECMWF Research Department Memo. R60-G, 15 pp.

  • Charnock, H., 1955: Wind stress on a water surface. Quart. J. Roy. Meteor. Soc., 81 , 639640.

  • Donelan, M., 1990: Air–sea interaction. The Sea. Vol. 9: Ocean Engineering Science, B. Le Mehaute and D. M. Hanes, Eds., Wiley and Sons, 239–292.

    • Search Google Scholar
    • Export Citation
  • Drennan, W., H. C. Graber, and M. A. Donelan, 1999: Evidence for the effects of swell and unsteady winds on marine wind stress. J. Phys. Oceanogr., 29 , 18531864.

    • Search Google Scholar
    • Export Citation
  • ECMWF, 1998: Physical processes. ECMWF Integrated Forecasting System Tech. Documentation 4, 146 pp.

  • Eymard, L., and Coauthors. 1999: Surface fluxes in the North Atlantic Current during CATCH/FASTEX. Quart. J. Roy. Meteor. Soc., 125 , 35623599.

    • Search Google Scholar
    • Export Citation
  • Fairall, C., E. Bradey, D. Rogers, J. Edson, and G. Young, 1996: Bulk parameterization of air–sea fluxes for the Tropical Ocean Global Atmosphere Coupled Ocean–Atmosphere Response Experiment. J. Geophys. Res., 101 , 37473764.

    • Search Google Scholar
    • Export Citation
  • Garrat, J., 1992: The Atmospheric Boundary Layer. Cambridge Atmospheric and Space Science Series, Cambridge University Press, 316 pp.

  • Gibson, R., P. Kållberg, S. Uppala, A. Hernandez, A. Nomura, and E. Serrano, 1997: The ERA description. The ECMWF Re-Analysis Project Report Series 1, 74 pp.

    • Search Google Scholar
    • Export Citation
  • Hare, J., P. Persson, C. Fairall, and J. Edson, 1999: Behavior of Charnock's relation for high wind conditions. Preprints, 13th Symp. on Boundary Layers and Turbulence, Dallas, TX, Amer. Meteor. Soc., 252–255.

    • Search Google Scholar
    • Export Citation
  • Henjes, K., M. Yelland, and P. Taylor, 1999: Effect of pulse averaging on sonic anemometer spectra. J. Atmos. Oceanic Technol., 16 , 181184.

    • Search Google Scholar
    • Export Citation
  • Janssen, J., 1997: Does wind stress depend on sea state or not? A statistic error analysis of HEXMAX data. Bound.-Layer Meteor., 83 , 479503.

    • Search Google Scholar
    • Export Citation
  • Janssen, J., . 1989: Wave-induced stress and the drag of air flow over sea waves. J. Phys. Oceanogr., 19 , 745754.

  • Janssen, J., . 1991: Quasi-linear theory of wind–wave generation applied to wave forecasting. J. Phys. Oceanogr., 21 , 16311642.

  • Janssen, J., . 1999: On the effect of ocean waves on the kinetic energy balance and consequences for the inertial dissipation technique. J. Phys. Oceanogr., 29 , 530534.

    • Search Google Scholar
    • Export Citation
  • Janssen, J., . 2001: Ocean waves do affect the kinetic energy balance. J. Phys. Oceanogr., 31 , 25372544.

  • Janssen, J., and P. Viterbo, 1996: Ocean waves and the atmospheric climate. J. Climate, 9 , 12691287.

  • Janssen, J., J. Doyle, J. Bidlot, B. Hansen, L. Isaksen, and P. Viterbo, 1999: The impact of ocean waves on the atmosphere. Proc. Seminar on Atmosphere–Surface Interaction, Reading, United Kingdom, ECMWF, 85–112.

    • Search Google Scholar
    • Export Citation
  • Komen, G., L. Cavaleri, M. Donelan, K. Hasselmann, S. Hasselmann, and P. Janssen, 1994: Dynamics and Modelling of Ocean Waves. Cambridge University Press, 532 pp.

    • Search Google Scholar
    • Export Citation
  • Komen, G., P. Janssen, V. Makin, and W. Oost, 1998: On the sea state dependence of the Charnock parameter. Global Atmos. Ocean Syst., 5 , 367388.

    • Search Google Scholar
    • Export Citation
  • Monin, A., and A. M. Obukhov, 1954: Basic laws of turbulent mixing in the ground layer of the atmosphere. Akad. Nauk. SSSR Geofiz. Inst. Tr., 24 , 163187.

    • Search Google Scholar
    • Export Citation
  • Pierson, W., and L. Moskowitz, 1964: A proposed spectral form for fully developed wind seas based on the similarity theory of S. A. Kitaigorodskii. J. Geophys. Res., 69 , 163187.

    • Search Google Scholar
    • Export Citation
  • Press, W., S. A. Teukolsky, W. Vetterling, and B. Flannery, 1992: Numerical Recipes, the Art of Scientific Computing. Cambridge University Press, 1020 pp.

    • Search Google Scholar
    • Export Citation
  • Smith, S., 1980: Wind stress and heat flux over the ocean in gale force winds. J. Phys. Oceanogr., 10 , 709726.

  • Smith, S., . 1988: Coefficients for sea surface wind stress, heat flux, and wind profiles as a function of wind speed and temperature. J. Geophys. Res., 93 , 1546715472.

    • Search Google Scholar
    • Export Citation
  • Smith, S., and Coauthors. 1992: Sea surface wind stress and drag coefficients: The HEXOS results. Bound.-Layer Meteor., 68 , 109142.

  • Sreenivasan, K., A. Chambers, and R. Antonia, 1978: Accuracy of moments of velocity and scalar fluctuations in the atmospheric surface layer. Bound.-Layer Meteor., 14 , 341359.

    • Search Google Scholar
    • Export Citation
  • Sterl, A., and H. Bonekamp, 2000: Comparison of wind stress from ERA and from WAM. Proc. Second Int. Conf. on Reanalyses, Reading, United Kingdom, World Meteorological Organisation, 149–152.

    • Search Google Scholar
    • Export Citation
  • Sterl, A., G. Komen, and P. Cotton, 1998: 15 years of global wave hindcasts using ERA winds. J. Geophys. Res., 103C , 54775492.

  • Stull, R., 1988: An Introduction to Boundary Layer Theory. Atmospheric Science Library, Kluwer Academic Publishers, 670 pp.

  • Taylor, P., and M. Yelland, 2000: On the apparent “imbalance” term in the turbulent kinetic energy budget. J. Atmos. Oceanic Technol., 17 , 8289.

    • Search Google Scholar
    • Export Citation
  • Taylor, P., and M. Yelland, . 2001: Comments on “On the effect ocean waves on the kinetic energy balance and consequences for the inertial dissipation technique.”. J. Phys. Oceanogr., 31 , 25322536.

    • Search Google Scholar
    • Export Citation
  • Uppala, S., J. Gibson, M. Fiorino, A. Hernandez, P. Kållberg, X. Li, K. Onogi, and S. Saarinen, 2000: ECMWF's second generation reanalysis ERA40. Proc. Second Int. Conf. on Reanalyses, Reading, UK, United Kingdom, World Meteorological Organisation WMO/TD-No. 985, 9–12.

    • Search Google Scholar
    • Export Citation
  • WGASF, 2000: Intercomparison and validation of ocean–atmosphere energy flux fields. Final report of Joint WCRP/SCOR Working Group on Air–Sea Fluxes (SCOR working group 110). WCRP Rep. 112, WMO/TD-No. 1036.

    • Search Google Scholar
    • Export Citation
  • Yelland, M., 1997: Wind stress over the open ocean. Ph.D. thesis, University of Southampton, 168 pp.

  • Yelland, M., . 1999: Does the wind stress depend on the sea-state? Wind-over-Wave Couplings: Perspectives and Prospects, S. Sajjadi, N. Thomas, and J. Hunt, Eds., Clarendon Press, 107–118.

    • Search Google Scholar
    • Export Citation
  • Yelland, M., and P. Taylor, 1996: Wind stress measurements from the open ocean. J. Phys. Oceanogr., 26 , 541558.

  • Yelland, M., P. Taylor, I. E. Consterdine, and M. H. Smith, 1994: The use of the inertial dissipation technique for shipboard wind stress determination. J. Atmos. Oceanic Technol., 11 , 10931108.

    • Search Google Scholar
    • Export Citation
  • Yelland, M., B. Moat, P. Taylor, R. Pascal, J. Hutchings, and V. Cornell, 1998: Wind stress measurements from the open ocean corrected for air-flow distortion by the ship. J. Phys. Oceanogr., 28 , 15111526.

    • Search Google Scholar
    • Export Citation
  • Zeng, X., M. Zhao, and R. Dickinson, 1998: Intercomparison of bulk aerodynamic algorithms for the computation of sea surface fluxes using TOGA COARE and TAO data. J. Climate, 11 , 26282644.

    • Search Google Scholar
    • Export Citation
All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 149 26 2
PDF Downloads 33 19 0

Statistical Comparisons of Observed and ECMWF Modeled Open Ocean Surface Drag

View More View Less
  • 1 Oceanographic Research Division, Royal Netherlands Meteorological Institute, De Bilt, Netherlands
  • | 2 European Centre for Medium-Range Weather Forecasts, Reading, United Kingdom
  • | 3 James Rennell Division, Southhampton Oceanography Centre, Southhampton, United Kingdom
Restricted access

Abstract

The surface-drag coefficients of two versions of the ECMWF's atmosphere–wave model are compared with those of uncoupled model versions and with those of inertial-dissipation measurements in the open ocean made by the RRS Discovery. It is found that the mean drag resulting from the latest coupled version is on average equal to that of the uncoupled version. However, both have a positive bias when compared with the RRS Discovery observations. This bias is discussed, also in the light of other observational open ocean data. In the second part of the paper, bulk parameterizations with and without parameters of collocated sea-state data are validated against the Discovery observations. Using published estimates of the error in friction velocity and the neutral 10-m winds, all bulk parameterizations score low on goodness-of-fit tests. The lowest scores are obtained for the constant Charnock parameter case, whereas the highest scores are obtained for a wave-age-dependent parameterization. On–off experiments are made for the corrections to the inertial-dissipation data that have been proposed in previous studies. These corrections concern the measurement height and the direct wave-induced turbulence in the lower atmosphere. The first correction results in a slightly better agreement, but the second reduces the goodness-of-fit of the bulk parameterizations.

Current affiliation: Civil Engineering and Geosciences, Delft University of Technology, Delft, Netherlands

Corresponding author address: Dr. H. Bonekamp, Oceanographic Research Division, Royal Netherlands Research Institute (KNMI), Box 201, AE De Bilt NL-3730, Netherlands. Email: j.g.bonekamp@ct.tudelft.nl

Abstract

The surface-drag coefficients of two versions of the ECMWF's atmosphere–wave model are compared with those of uncoupled model versions and with those of inertial-dissipation measurements in the open ocean made by the RRS Discovery. It is found that the mean drag resulting from the latest coupled version is on average equal to that of the uncoupled version. However, both have a positive bias when compared with the RRS Discovery observations. This bias is discussed, also in the light of other observational open ocean data. In the second part of the paper, bulk parameterizations with and without parameters of collocated sea-state data are validated against the Discovery observations. Using published estimates of the error in friction velocity and the neutral 10-m winds, all bulk parameterizations score low on goodness-of-fit tests. The lowest scores are obtained for the constant Charnock parameter case, whereas the highest scores are obtained for a wave-age-dependent parameterization. On–off experiments are made for the corrections to the inertial-dissipation data that have been proposed in previous studies. These corrections concern the measurement height and the direct wave-induced turbulence in the lower atmosphere. The first correction results in a slightly better agreement, but the second reduces the goodness-of-fit of the bulk parameterizations.

Current affiliation: Civil Engineering and Geosciences, Delft University of Technology, Delft, Netherlands

Corresponding author address: Dr. H. Bonekamp, Oceanographic Research Division, Royal Netherlands Research Institute (KNMI), Box 201, AE De Bilt NL-3730, Netherlands. Email: j.g.bonekamp@ct.tudelft.nl

Save