Editorial Type:
Article
Article Type:
Research Article

WRF Model Sensitivity to Choice of Parameterization over South America: Validation against Surface Variables

Juan J. Ruiz Centro de Investigaciones del Mar y la Atmósfera (CONICET/UBA) y Departamento de Ciencias de la Atmósfera y los Océanos, FCEN-UBA, Buenos Aires, Argentina

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Celeste Saulo Centro de Investigaciones del Mar y la Atmósfera (CONICET/UBA) y Departamento de Ciencias de la Atmósfera y los Océanos, FCEN-UBA, Buenos Aires, Argentina

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Julia Nogués-Paegle Department of Meteorology, University of Utah, Salt Lake City, Utah

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Print Publication:
01 Aug 2010
DOI:
https://doi.org/10.1175/2010MWR3358.1
Page(s):
3342–3355
Restricted access

Abstract

The Weather and Research Forecast model is tested over South America in different configurations to identify the one that gives the best estimates of observed surface variables.

Systematic, nonsystematic, and total errors are computed for 48-h forecasts initialized with the NCEP Global Data Assimilation System (GDAS). There is no unique model design that best fits all variables over the whole domain, and nonsystematic errors for all configurations differ little from one another; such differences are in most cases smaller than the observed day-to-day variability. An ensemble mean consisting of runs with different parameterizations gives the best skill for the whole domain.

Surface variables are highly sensitive to the choice of land surface models. Surface temperature is well represented by the Noah land model, but dewpoint temperature is best estimated by the simplest land surface model considered here, which specifies soil moisture based on climatology. This underlines the need for better understanding of humid processes at the subgrid scale.

Surface wind errors decrease the intensity of the low-level jet, reducing expected heat and moisture advection over southeast South America (SESA), with negative precipitation errors over SESA and positive biases over the South Atlantic convergence zone (SACZ). This pattern of errors suggests feedbacks between wind errors, precipitation, and surface processes as follows: an increase of precipitation over the SACZ produces compensating descent in SESA, with more stable stratification, less rain, less soil moisture, and decreased rain. This is a clear example of how local errors are related to regional circulation, and suggests that improvement of model performance requires not only better parameterizations at the subgrid scales, but also improved regional models.

Corresponding author address: Celeste Saulo, Dpto. de Cs. de la Atmósfera y los Océanos, FCEyN Centro de Investigaciones del Mar y la Atmósfera (CIMA), CONICET/UBA Intendente Guiraldes 2160, Ciudad Universitaria Pabellón II, 2do. Piso (C1428EHA), Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina. Email: saulo@cima.fcen.uba.ar

Abstract

The Weather and Research Forecast model is tested over South America in different configurations to identify the one that gives the best estimates of observed surface variables.

Systematic, nonsystematic, and total errors are computed for 48-h forecasts initialized with the NCEP Global Data Assimilation System (GDAS). There is no unique model design that best fits all variables over the whole domain, and nonsystematic errors for all configurations differ little from one another; such differences are in most cases smaller than the observed day-to-day variability. An ensemble mean consisting of runs with different parameterizations gives the best skill for the whole domain.

Surface variables are highly sensitive to the choice of land surface models. Surface temperature is well represented by the Noah land model, but dewpoint temperature is best estimated by the simplest land surface model considered here, which specifies soil moisture based on climatology. This underlines the need for better understanding of humid processes at the subgrid scale.

Surface wind errors decrease the intensity of the low-level jet, reducing expected heat and moisture advection over southeast South America (SESA), with negative precipitation errors over SESA and positive biases over the South Atlantic convergence zone (SACZ). This pattern of errors suggests feedbacks between wind errors, precipitation, and surface processes as follows: an increase of precipitation over the SACZ produces compensating descent in SESA, with more stable stratification, less rain, less soil moisture, and decreased rain. This is a clear example of how local errors are related to regional circulation, and suggests that improvement of model performance requires not only better parameterizations at the subgrid scales, but also improved regional models.

Corresponding author address: Celeste Saulo, Dpto. de Cs. de la Atmósfera y los Océanos, FCEyN Centro de Investigaciones del Mar y la Atmósfera (CIMA), CONICET/UBA Intendente Guiraldes 2160, Ciudad Universitaria Pabellón II, 2do. Piso (C1428EHA), Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina. Email: saulo@cima.fcen.uba.ar

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  • Aligo, E. A., W. A. Gallus Jr., and M. Segal, 2007: Summer rainfall forecast spread in an ensemble initialized with different soil moisture analyses. Wea. Forecasting, 22 , 299–214.

    • Search Google Scholar
    • Export Citation

  • Betts, A. K., 1986: A new convective adjustment scheme. Part I: Observational and theoretical basis. Quart. J. Roy. Meteor. Soc., 112 , 677–691.

    • Search Google Scholar
    • Export Citation

  • Blázquez, J., and M. N. Nuñez, 2009: Sensitivity to convective parameterization in the WRF regional model in southern South America. Preprints, Ninth Int. Conf. on Southern Hemisphere Meteorology and Oceanography, Melbourne, Australia, Amer. Meteor. Soc., 6 pp.

    • Search Google Scholar
    • Export Citation

  • Case, J. L., W. L. Crosson, S. V. Kumar, W. M. Lapenta, and C. D. Peters-Lidard, 2008: Impacts of high-resolution land surface initialization on regional sensible weather forecasts from the WRF model. J. Hydrometeor., 9 , 1249–1266.

    • Search Google Scholar
    • Export Citation

  • Chen, F., and J. Dudhia, 2001: Coupling an advanced land-surface/hydrology model with the Penn State–NCAR MM5 modeling system. Part I: Model description and implementation. Mon. Wea. Rev., 129 , 569–585.

    • Search Google Scholar
    • Export Citation

  • Cheng, W. Y. Y., and W. J. Steenburgh, 2005: Evaluation of surface sensible weather forecasts by the WRF and the Eta models over the western United States. Wea. Forecasting, 20 , 812–821.

    • Search Google Scholar
    • Export Citation

  • Dudhia, J., 1989: Numerical study of convection observed during the winter monsoon experiment using a mesoscale two-dimensional model. J. Atmos. Sci., 46 , 3077–3107.

    • Search Google Scholar
    • Export Citation

  • Ferrier, B. S., Y. Jin, Y. Lin, T. Black, E. Rogers, and G. DiMego, 2002: Implementation of a new grid-scale cloud and precipitation scheme in the NCEP Eta model. Preprints, 15th Conf. on Numerical Weather Prediction, San Antonio, TX, Amer. Meteor. Soc., 280–283.

    • Search Google Scholar
    • Export Citation

  • Gevaerd, R., S. Freitas, M. Longo, D. Soares Moreira, M. A. F. da Silva Dias, and P. L. da Silva Dias, 2006: Operational soil moisture estimate for initialization of numerical weather forecast models. Part II: The effect of initial soil moisture and cumulus parameterization of a dry line convective system (in Portuguese). Rev. Brasil. Meteor., 21 , (3A). 74–88.

    • Search Google Scholar
    • Export Citation

  • Grell, G. A., and D. Devenyi, 2002: A generalized approach to parameterizing convection combining ensemble and data assimilation techniques. Geophys. Res. Lett., 29 , 1693. doi:10.1029/2002GL015311.

    • Search Google Scholar
    • Export Citation

  • Hong, S-Y., and H-L. Pan, 1996: Nonlocal boundary layer vertical diffusion in a medium-range forecast model. Mon. Wea. Rev., 124 , 2322–2339.

    • Search Google Scholar
    • Export Citation

  • Janjic, Z. I., 1994: The step-mountain Eta coordinate model: Further developments of the convection, viscous sublayer, and turbulence closure schemes. Mon. Wea. Rev., 122 , 927–945.

    • Search Google Scholar
    • Export Citation

  • Janjic, Z. I., 2002: Nonsingular Implementation of the Mellor–Yamada level 2.5 scheme in the CEP Meso model. NCEP Office Note 437, 61 pp.

    • Search Google Scholar
    • Export Citation

  • Jankov, I., W. A. Gallus, M. Segal, B. Shaw, and S. E. Koch, 2005: The impact of different WRF model physical parameterizations and their interactions on warm season MCS rainfall. Wea. Forecasting, 20 , 1048–1060.

    • Search Google Scholar
    • Export Citation

  • Kain, J. S., 2004: The Kain–Fritsch convective parameterization: An update. J. Appl. Meteor., 43 , 170–181.

  • Krishnamurti, T. N., C. M. Kishtawal, T. E. LaRow, D. R. Bachiochi, Z. Zhang, C. E. Willford, S. Gadgil, and S. Surendran, 1999: Improved weather and seasonal climate forecast from multimodel superensemble. Science, 285 , 1548–1550.

    • Search Google Scholar
    • Export Citation

  • Liebmann, B., G. N. Kiladis, C. S. Vera, A. C. Saulo, and L. M. V. Carvalho, 2004: Subseasonal variations of rainfall in South America in the vicinity of the low-level jet east of the Andes and comparison to those in the South Atlantic convergence zone. J. Climate, 17 , 3829–3842.

    • Search Google Scholar
    • Export Citation

  • Mlawer, E. J., S. J. Taubman, P. D. Brown, M. J. Iacono, and S. A. Clough, 1997: Radiative transfer for inhomogeneous atmosphere: RRTM, a validated correlated-k model for the long wave. J. Geophys. Res., 102 , (D14). 16663–16682.

    • Search Google Scholar
    • Export Citation

  • Nogués-Paegle, J. N., and K. C. Mo, 1997: Alternating wet and dry conditions over South America during summer. Mon. Wea. Rev., 125 , 279–291.

    • Search Google Scholar
    • Export Citation

  • Penalba, O., and Coauthors, 2004: Daily rainfall data over Argentina and Uruguay during SALLJEX. CLIVAR Exchanges, No. 9, International CLIVAR Project Office, Southampton, United Kingdom, 29–31.

    • Search Google Scholar
    • Export Citation

  • Pessacg, N., 2008: Precipitation sensitivity experiments using WRF (in Spanish). Licensee dissertation, Dept. of Atmospheric and Oceanographic Sciences, University of Buenos Aires, Argentina, 80 pp.

  • Raftery, A. E., T. Gneiting, F. Balabdaoui, and Y. M. Polakowski, 2005: Using Bayesian model averaging to calibrate forecast ensembles. Mon. Wea. Rev., 133 , 1155–1174.

    • Search Google Scholar
    • Export Citation

  • Ries, H., and K. H. Schlünzen, 2009: Evaluation of a mesoscale model with different surface parameterizations and vertical resolutions for the Bay of Valencia. Mon. Wea. Rev., 137 , 2646–2661.

    • Search Google Scholar
    • Export Citation

  • Rodell, M., and Coauthors, 2004: The Global Land Data Assimilation System. Bull. Amer. Meteor. Soc., 85 , 381–394.

  • Ruiz, J. J., A. C. Saulo, and E. Kalnay, 2009: Comparison of methods to generate probabilistic quantitative precipitation forecasts over South America. Wea. Forecasting, 24 , 319–336.

    • Search Google Scholar
    • Export Citation

  • Salio, P., M. Nicolini, and A. C. Saulo, 2002: Chaco low-level jet events characterization during the austral summer season by ERA reanalysis. J. Geophys. Res., 107 , 4816. doi:10.1029/2001JD001315.

    • Search Google Scholar
    • Export Citation

  • Saulo, A. C., S. Cardazzo, J. Ruiz, C. Campetella, and A. Rolla, 2008: Experimental forecast system at the Research Center for the sea and the atmosphere (in Spanish). Meteorologica, 33 , 83–97.

    • Search Google Scholar
    • Export Citation

  • Saulo, C., L. Ferreira, J. Nogués-Paegle, M. Seluchi, and J. Ruiz, 2010: Land–atmosphere interactions during a northwestern Argentina low event. Mon. Wea. Rev., 138 , 2481–2498.

    • Search Google Scholar
    • Export Citation

  • Seluchi, M. E., and S. C. Chou, 2000: Adjustment of the Betts–Miller convective parameterization in the ETA/CPTEC regional model (in Spanish). Meteorologica, 25 , 45–56.

    • Search Google Scholar
    • Export Citation

  • Shukla, J., R. Hagedorn, B. Hoskins, J. Kinter, J. Marotzke, M. Miller, T. N. Palmer, and J. Slingo, 2009: Revolution in climate prediction is both necessary and possible: A declaration at the world modelling summit for climate prediction. Bull. Amer. Meteor. Soc., 90 , 175–178.

    • Search Google Scholar
    • Export Citation

  • Silva Dias, P. L., D. Soares Moreira, and G. D. Neto, 2006: The MASTER Model Ensemble System (MSMES). Preprints, Eighth Int. Conf. on Southern Hemisphere Meteorology and Oceanography, Foz do Iguaçu, Brazil, Amer. Meteor. Soc., 4 pp.

    • Search Google Scholar
    • Export Citation

  • Skamarock, W. C., J. B. Klemp, J. Dudhia, D. O. Gill, D. M. Barker, W. Wang, and J. G. Powers, 2005: A description of the Advanced Research WRF version 2. NCAR Tech Note NCAR TN-468+STR, 100 pp.

    • Search Google Scholar
    • Export Citation

  • Smirnova, T. G., J. M. Brown, and S. G. Benjamin, 1997: Performance of different soil model configurations in simulating ground surface temperature and surface fluxes. Mon. Wea. Rev., 125 , 1870–1884.

    • Search Google Scholar
    • Export Citation

  • Vera, C., and Coauthors, 2006: The South American low-level jet experiment. Bull. Amer. Meteor. Soc., 87 , 63–77.

  • Wilks, D. S., 2006: Statistical Methods in Atmospheric Sciences. 2nd ed. Academic Press, 627 pp.

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