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Fertig, Elana J.; Harlim, John; Hunt, Brian R. (2007)
Publisher: Co-Action Publishing
Journal: Tellus A
Languages: English
Types: Article
Subjects:
We formulate a four-dimensional Ensemble Kalman Filter (4D-LETKF) that minimizes a cost function similar to that in a 4D-VAR method. Using perfect model experiments with the Lorenz-96 model, we compare assimilation of simulated asynchronous observations with 4D-VAR and 4D-LETKF. We find that both schemes have comparable error when 4D-LETKF is performed sufficiently frequently and when 4D-VAR is performed over a sufficiently long analysis time window. We explore how the error depends on the time between analyses for 4D-LETKF and the analysis time window for 4D-VAR.
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    • Anderson, J. L. 2001. An ensemble adjustment Kalman filter for data assimilation. Mon. Wea. Rev. 129, 2884-2903.
    • Bishop, C. H., Etherton, B. and Majumdar, S. J. 2001. Adaptive sampling with the ensemble transform Kalman filter. Part I: Theoretical aspects. Mon. Wea. Rev. 129, 420-436.
    • Burgers, G., van Leeuwen, P. J. and Evensen, G. 1998. Analysis scheme in the ensemble Kalman filter. Mon. Wea. Rev. 126, 1719-1724.
    • Courtier, P., The´paut, J. N. and Hollingsworth, A. 1994. A strategy for operational implementation of 4D-VAR, using an incremental approach. Quart. J. R. Meteorol. Soc. 120, 1367-1387.
    • Evensen, G. 1994. Sequential data assimilation with a non-linear quasigeostropic model using Monte Carlo Methods to forecast error statistics. J. Geophys. Res. 99, 10143-10162.
    • Evensen, G. and van Leeuwen, P. J. 2000. An ensemble Kalman smoother for nonlinear dynamics. Mon. Wea. Rev. 128, 1852-1867.
    • Houtekamer, P. L. and Mitchell, H. L. 1998. Data assimilation using an ensemble Kalman filter technique. Mon. Wea. Rev. 126, 796-811.
    • Houtekamer, P. L., Mitchell, H. L., Pellerin, G., Buehner, M., Charron, M, et al. 2005. Atmospheric data assimilation with the ensemble Kalman filter: Results with real observations. Mon. Wea. Rev. 133, 604-620.
    • Houtekamer, P. L. and Mitchell, H. L. 2006. Ensemble Kalman Filtering. Quart. J. R. Meteorol. Soc., in press.
    • Hunt, B. R., Kalnay, E., Kostelich, E. J., Ott, E., Patil, D. J. and co-authors. 2004. Four-dimensional ensemble Kalman filtering. Tellus 56A, 273-277.
    • Lawson, L.M, Spitz, Y. H., Hofmann, E. E. and Long, R. B. 1995. A data assimilation technique applied to a predator-prey model. Bull. Math. Biol. 57(4), 593-617.
    • Le Dimet, F. X. and Talagrand, O. 1986. Variational algorithm for analysis and assimilation of meteorological observations: Theoretical aspects. Tellus 38A, 97-110.
    • Lorenc, A. C. 2003. The potential of the ensemble Kalman filter for NWP-a comparison with 4D-VAR. Quart. J. R. Meteorol. Soc. 129, 3183-3203.
    • Lorenz, E. N. 1996. Predictability-a problem partly solved. In Proceedings on predictability, held at ECMWF on 4-8 September 1995.
    • Ott, E., Hunt, B. R., Szunoygh, I., Zimin, A., Kostelich, E. J., and co-authors. 2004. A local ensemble Kalman filter for atmospheric data assimilation. Tellus 56A, 415-428.
    • Parrish, D. F. and Derber, J. C. 1992. The National Meteorological Center's spectral statistical-interpolation analysis system. Mon. Wea. Rev. 120(8), 1747-1763.
    • Press, W. H., Flannery, B. P., Teukolsky, S. A. and Vetterling, W. V. 1992. Numerical Recipes in Fortran. Cambridge University Press, New York.
    • Rabier, F., The´paut, J. N. and Courtier, P. 1998. Extended assimilation and forecast experiments with a four-dimensional variational assimilation system. Quart. J. R. Meteorol. Soc. 124, 1861-1887.
    • Rabier, F., Ja¨rvien, H., Mahfouf, J. F. and Simmons, A. 2000. The ECMWF operational implementation of four-dimensional variational assimilation: Experimental results with simplified physics. Quart. J. R. Meteorol. Soc. 126, 1148-1170.
    • Szunoygh, I., Kostelich, E. J., Gyarmati, G., Patil, D. J., Kalnay, E., and co-authors. 2005. Assessing a local ensemble Kalman filter: Perfect model experiments with the National Centers for Environmental Prediction global model. Tellus 57A, 528-545.
    • 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(7), 1590-1605.
    • Wang, X., Hamill, T.M, Whitaker, J. S. and Bishop, C. H. 2006. A comparison of hybrid ensemble transform Kalman filter-OI and ensemble square-root filter analysis schemes. Mon. Wea. Rev., in press.
    • Whitaker, J. S. and Hamill, T. M. 2002. Ensemble data assimilation without perturbed observations. Mon. Wea. Rev. 130, 1913- 1924.
    • Whitaker, J. S., Compo, G. P., Wei, X. and Hamill, T. M. 2004. Reanalysis without radiosondes using ensemble data assimilation. Mon. Wea. Rev. 132, 1190-1200.
    • Whitaker, J. S., Hamill, T. M., Wei, X., Song, Y. and Toth, Z. 2006. Ensemble data assimilation with the NCEP global forecast system. Mon. Wea. Rev., submitted.
    • Zupanski, M. 2005. Maximum likelihood ensemble filter: Theoretical aspects. Mon. Wea. Rev. 133, 1710-1726.
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