The Australian community climate and earth system simulator global and regional ensemble prediction scheme

Terence John O'Kane, Michael J Naughton, Yi Xiao


We report on progress in the development of the Australian Community Climate and Earth Systems Simulator Global and Regional Ensemble numerical weather Prediction Scheme at the Australian Bureau of Meteorology. Based on the UK Met Office ensemble, AGREPS implements an Ensemble Transform Kalman Filter to generate independent initial perturbations as fast growing disturbances with structures and growth rates typical of the analysis errors. This method allows information about the fast growing errors to be incorporated into the initial perturbations for the forecast. An ensemble of model states is propagated, using the numerical weather prediction system and observing network at the Australian Bureau of Meteorology, from which covariances are constructed then localized and inflated to minimize the effect of small sample size.

  • Anderson, J. L., 2001 An ensemble adjustment Kalman filter for data assimilation. Mon. Wea. Rev. 129, 2884--2903 doi:10.1175/1520-0493(2001)129<2884:AEAKFF>2.0.CO;2
  • Bishop, C. H., Hodyss, D., 2007 Flow adaptive moderation of spurious ensemble correlation and its use in ensemble-based data assimilation. Q. J. R. Meteorol. Soc. 133, 2029--2044 doi:10.1002/qj.169
  • Buehner, M., 2005 Ensemble-derived stationary and flow-dependent background-error covariances: Evaluation in a quasi-operational NWP setting. Q. J. R. Meteorol. Soc. 131, 1013--1043 doi:10.1256/qj.04.n
  • Charney, J. G., 1966 The feasibility of a global observation and analysis experiment. Bull. Amer. Meteor. Soc. 47, 200--220
  • Hamill, T. M., Whitaker, J. S., and Snyder, C., 2001 Distance-dependent filtering of background error covariance estimates in an ensemble Kalman filter. Mon. Wea. Rev. 129, 2776--2790 doi:10.1175/1520-0493(2001)129<2776:DDFOBE>2.0.CO;2
  • Houtekamer, P. L., and Mitchell, H. L., 1998, Data assimilation using an ensemble Kalman filter technique. Mon. Wea. Rev. 126, 796--811 doi:10.1175/1520-0493(1998)126<0796:DAUAEK>2.0.CO;2
  • Kasahara, A., 1972 Simulation experiments for meteorological observing systems for GARP. Bull. Amer. Meteor. Soc. 53, 252--264
  • O'Kane, T. J., and Frederiksen, J. S., 2008a,A comparison of statistical dynamical and ensemble prediction during blocking. J. Atmos. Sci. 65, 426--447 doi:10.1175/2007JAS2300.1
  • O'Kane, T. J., and Frederiksen, J. S., 2008b Comparison of statistical dynamical, square root and ensemble Kalman filters. entropy In Press
  • Purser, J., 1996 Arrangement of ensemble in a simplex to produce given first and second moments, NCEP Internal Report. Available from the author at
  • Smagorinsky, J., 1969 Problems and promises of deterministic extended range forecasting. Bull. Amer. Meteor. Soc. 50, 286--311
  • Tippett, M. K., Anderson, J. L., Bishop, C. H., Hamill, T. M., and Whitaker, J. S., 2003,Ensemble square root filters. Mon. Wea. Rev. 131, 1485--1490 doi:10.1175/1520-0493(2003)131<1485:ESRF>2.0.CO;2
  • Toth, Z., and Kalnay, E., 1997,Ensemble forecasting at NCEP and the breeding method. Mon. Wea. Rev. 125, 3297--3319 doi:10.1175/1520-0493(1997)125<3297:EFANAT>2.0.CO;2
  • Tracton, M. S., and Kalnay, E., 1993,Operational ensemble prediction at National Meteorological centre: Practical aspects. Weather and Forecasting 8, 379--398 doi:10.1175/1520-0434(1993)008<0379:OEPATN>2.0.CO;2
  • Wang, X., and Bishop, C. H., 2003,A comparison of breeding and ensemble transform Kalman filter ensemble forecast schemes. J. Atmos. Sci. 60, 1140--1158 doi:10.1175/1520-0469(2003)060<1140:ACOBAE>2.0.CO;2
  • Wang, X., Bishop, C. H., and Julier, S. J., 2004,Which is better, an ensemble of positive-negative pairs or a centered spherical simplex ensemble. Mon. Wea. Rev. 132, 1590--1605 doi:10.1175/1520-0493(2004)132<1590:WIBAEO>2.0.CO;2
  • Wei, M., Toth, Z., Wobus, R., Zhu, Y., Bishop, C. H. and Wang, X., 2006 {Ensemble Transform Kalman Filter-based ensemble perturbations in an operational global prediction system at NCEP.} Tellus, 58A, 2006, 28--44 doi:10.1111/j.1600-0870.2006.00159.x

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