Intercomparison of Targeted Observation Guidance for Tropical Cyclones in the Northwestern Pacific

Chun-Chieh Wu Department of Atmospheric Sciences, National Taiwan University, Taipei, Taiwan

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Jan-Huey Chen Department of Atmospheric Sciences, National Taiwan University, Taipei, Taiwan

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Sharanya J. Majumdar RSMAS Division of Meteorology and Physical Oceanography, University of Miami, Miami, Florida

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Melinda S. Peng Naval Research Laboratory, Monterey, California

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Carolyn A. Reynolds Naval Research Laboratory, Monterey, California

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Sim D. Aberson NOAA/AOML Hurricane Research Division, Miami, Florida

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Roberto Buizza European Centre for Medium-Range Weather Forecasts, Reading, United Kingdom

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Munehiko Yamaguchi *Japan Meteorological Agency, Tokyo, Japan

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Shin-Gan Chen Department of Atmospheric Sciences, National Taiwan University, Taipei, Taiwan

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Tetsuo Nakazawa Meteorological Research Institute, Japan Meteorological Agency, Tokyo, Japan

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Kun-Hsuan Chou Department of Atmospheric Sciences, Chinese Culture University, Taipei, Taiwan

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Abstract

This study compares six different guidance products for targeted observations over the northwest Pacific Ocean for 84 cases of 2-day forecasts in 2006 and highlights the unique dynamical features affecting the tropical cyclone (TC) tracks in this basin. The six products include three types of guidance based on total-energy singular vectors (TESVs) from different global models, the ensemble transform Kalman filter (ETKF) based on a multimodel ensemble, the deep-layer mean (DLM) wind variance, and the adjoint-derived sensitivity steering vector (ADSSV). The similarities among the six products are evaluated using two objective statistical techniques to show the diversity of the sensitivity regions in large, synoptic-scale domains and in smaller domains local to the TC. It is shown that the three TESVs are relatively similar to one another in both the large and the small domains while the comparisons of the DLM wind variance with other methods show rather low similarities. The ETKF and the ADSSV usually show high similarity because their optimal sensitivity usually lies close to the TC. The ADSSV, relative to the ETKF, reveals more similar sensitivity patterns to those associated with TESVs. Three special cases are also selected to highlight the similarities and differences among the six guidance products and to interpret the dynamical systems affecting the TC motion in the northwestern Pacific. Among the three storms studied, Typhoon Chanchu was associated with the subtropical high, Typhoon Shanshan was associated with the midlatitude trough, and Typhoon Durian was associated with the subtropical jet. The adjoint methods are found to be more capable of capturing the signal of the dynamic system that may affect the TC movement or evolution than are the ensemble methods.

Corresponding author address: Dr. Chun-Chieh Wu, Dept. of Atmospheric Sciences, National Taiwan University, No. 1, Sec. 4, Roosevelt Rd., Taipei 106, Taiwan. Email: cwu@typhoon.as.ntu.edu.tw

This article included in the Targeted Observations, Data Assimilation, and Tropical Cyclone Predictability special collection.

Abstract

This study compares six different guidance products for targeted observations over the northwest Pacific Ocean for 84 cases of 2-day forecasts in 2006 and highlights the unique dynamical features affecting the tropical cyclone (TC) tracks in this basin. The six products include three types of guidance based on total-energy singular vectors (TESVs) from different global models, the ensemble transform Kalman filter (ETKF) based on a multimodel ensemble, the deep-layer mean (DLM) wind variance, and the adjoint-derived sensitivity steering vector (ADSSV). The similarities among the six products are evaluated using two objective statistical techniques to show the diversity of the sensitivity regions in large, synoptic-scale domains and in smaller domains local to the TC. It is shown that the three TESVs are relatively similar to one another in both the large and the small domains while the comparisons of the DLM wind variance with other methods show rather low similarities. The ETKF and the ADSSV usually show high similarity because their optimal sensitivity usually lies close to the TC. The ADSSV, relative to the ETKF, reveals more similar sensitivity patterns to those associated with TESVs. Three special cases are also selected to highlight the similarities and differences among the six guidance products and to interpret the dynamical systems affecting the TC motion in the northwestern Pacific. Among the three storms studied, Typhoon Chanchu was associated with the subtropical high, Typhoon Shanshan was associated with the midlatitude trough, and Typhoon Durian was associated with the subtropical jet. The adjoint methods are found to be more capable of capturing the signal of the dynamic system that may affect the TC movement or evolution than are the ensemble methods.

Corresponding author address: Dr. Chun-Chieh Wu, Dept. of Atmospheric Sciences, National Taiwan University, No. 1, Sec. 4, Roosevelt Rd., Taipei 106, Taiwan. Email: cwu@typhoon.as.ntu.edu.tw

This article included in the Targeted Observations, Data Assimilation, and Tropical Cyclone Predictability special collection.

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  • Aberson, S. D., 2002: Two years of hurricane synoptic surveillance. Wea. Forecasting, 17 , 11011110.

  • Aberson, S. D., 2003: Targeted observations to improve operational tropical cyclone track forecast guidance. Mon. Wea. Rev., 131 , 16131628.

    • Search Google Scholar
    • Export Citation
  • Aberson, S. D., 2008: Large forecast degradations due to synoptic surveillance during the 2004 and 2005 hurricane seasons. Mon. Wea. Rev., 136 , 31383150.

    • Search Google Scholar
    • Export Citation
  • Aberson, S. D., and J. L. Franklin, 1999: Impact on hurricane track and intensity forecast of GPS dropsonde observations from the first-season flights of the NOAA Gulfstream-IV jet aircraft. Bull. Amer. Meteor. Soc., 80 , 421427.

    • Search Google Scholar
    • Export Citation
  • Bishop, C. H., B. J. Etherton, and S. J. Majumdar, 2001: Adaptive sampling with the ensemble transform Kalman filter. Part I: Theoretical aspects. Mon. Wea. Rev., 129 , 420436.

    • Search Google Scholar
    • Export Citation
  • Buizza, R., 1994: Localization of optimal perturbations using a projection operator. Quart. J. Roy. Meteor. Soc., 120 , 16471681.

  • Buizza, R., and A. Montani, 1999: Targeted observations using singular vectors. J. Atmos. Sci., 56 , 29652985.

  • Buizza, R., C. Cardinali, G. Kelly, and J-N. Thépaut, 2007: The value of observations. II: The value of observations located in singular-vector-based target areas. Quart. J. Roy. Meteor. Soc., 133 , 18171832.

    • Search Google Scholar
    • Export Citation
  • Cardinali, C., R. Buizza, G. Kelly, M. Shapiro, and J-N. Thépaut, 2007: The value of observations. III: Influence of weather regimes on targeting. Quart. J. Roy. Meteor. Soc., 133 , 18331842.

    • Search Google Scholar
    • Export Citation
  • Chou, K-H., and C-C. Wu, 2008: Development of the typhoon initialization in a mesoscale model—Combination of the bogused vortex with the dropwindsonde data in DOTSTAR. Mon. Wea. Rev., 136 , 865879.

    • Search Google Scholar
    • Export Citation
  • Gelaro, R., T. E. Rosmond, and R. Daley, 2002: Singular vector calculations with an analysis error variance metric. Mon. Wea. Rev., 130 , 11661186.

    • Search Google Scholar
    • Export Citation
  • Grell, G. A., J. Dudhia, and D. R. Stauffer, 1995: A description of the fifth generation Penn State/NCAR Mesoscale Model (MM5). NCAR Tech. Note NCAR/TN-398+STR, 122 pp.

    • Search Google Scholar
    • Export Citation
  • Joly, A., and Coauthors, 1997: The Fronts and Atlantic Storm-Track Experiment (FASTEX): Scientific objectives and experimental design. Bull. Amer. Meteor. Soc., 78 , 19171940.

    • Search Google Scholar
    • Export Citation
  • Kelly, G., J-N. Thépaut, R. Buizza, and C. Cardinali, 2007: The value of observations. I: Data denial experiments for the Atlantic and the Pacific. Quart. J. Roy. Meteor. Soc., 133 , 18031815.

    • Search Google Scholar
    • Export Citation
  • Krishnamurti, T. N., 1961: The subtropical jet stream of the winter. J. Atmos. Sci., 18 , 172191.

  • Langland, R. H., and N. L. Baker, 2004: Estimation of observation impact using the NRL atmospheric variational data assimilation system. Tellus, 56A , 189201.

    • Search Google Scholar
    • Export Citation
  • Langland, R. H., and Coauthors, 1999: The North Pacific Experiment, NORPEX-98: Targeted observations for improved North American weather forecasts. Bull. Amer. Meteor. Soc., 80 , 13631384.

    • Search Google Scholar
    • Export Citation
  • Leutbecher, M., 2003: A reduced rank estimate of forecast error variance changes due to intermittent modifications of the observing network. J. Atmos. Sci., 60 , 729742.

    • Search Google Scholar
    • Export Citation
  • Mahfouf, J-F., and F. Rabier, 2000: The ECMWF operational implementation of four-dimensional variational assimilation. Part II: Experimental results with improved physics. Quart. J. Roy. Meteor. Soc., 126 , 11711190.

    • Search Google Scholar
    • Export Citation
  • Majumdar, S. J., C. H. Bishop, B. J. Etherton, and Z. Toth, 2002a: Adaptive sampling with the ensemble transform Kalman filter. Part II: Field program implementation. Mon. Wea. Rev., 130 , 13561369.

    • Search Google Scholar
    • Export Citation
  • Majumdar, S. J., C. H. Bishop, R. Buizza, and R. Gelaro, 2002b: A comparison of ensemble-transform Kalman-filter targeting guidance with ECMWF and NRL total-energy singular-vector guidance. Quart. J. Roy. Meteor. Soc., 128 , 25272549.

    • Search Google Scholar
    • Export Citation
  • Majumdar, S. J., S. D. Aberson, C. H. Bishop, R. Buizza, M. S. Peng, and C. A. Reynolds, 2006: A comparison of adaptive observing guidance for Atlantic tropical cyclones. Mon. Wea. Rev., 134 , 23542372.

    • Search Google Scholar
    • Export Citation
  • Palmer, T. N., R. Gelaro, J. Barkmeijer, and R. Buizza, 1998: Singular vectors, metrics, and adaptive observations. J. Atmos. Sci., 55 , 633653.

    • Search Google Scholar
    • Export Citation
  • Peng, M. S., and C. A. Reynolds, 2006: Sensitivity of tropical cyclone forecasts as revealed by singular vectors. J. Atmos. Sci., 63 , 25082528.

    • Search Google Scholar
    • Export Citation
  • Reynolds, C. A., M. S. Peng, S. J. Majumdar, S. D. Aberson, C. H. Bishop, and R. Buizza, 2007: Interpretation of adaptive observing guidance for Atlantic tropical cyclones. Mon. Wea. Rev., 135 , 40064029.

    • Search Google Scholar
    • Export Citation
  • Rosmond, T. E., 1997: A technical description of the NRL adjoint model system. NRL/MR/7532/97/7230, Naval Research Laboratory, Monterey, CA, 62 pp.

    • Search Google Scholar
    • Export Citation
  • Szunyogh, I., Z. Toth, R. E. Morss, S. J. Majumdar, B. J. Etherton, and C. H. Bishop, 2000: The effect of targeted dropsonde observations during the 1999 Winter Storm Reconnaissance Program. Mon. Wea. Rev., 128 , 35203537.

    • Search Google Scholar
    • Export Citation
  • Szunyogh, I., Z. Toth, A. V. Zimin, S. J. Majumdar, and A. Persson, 2002: Propagation of the effect of targeted observations: The 2000 Winter Storm Reconnaissance Program. Mon. Wea. Rev., 130 , 11441165.

    • Search Google Scholar
    • Export Citation
  • Toth, Z., and E. Kalnay, 1993: Ensemble forecasting at NMC: The generation of perturbations. Bull. Amer. Meteor. Soc., 74 , 23172330.

  • Wei, M., Z. Toth, R. Wobus, and Y. Zhu, 2008: Initial perturbations based on the ensemble transform (ET) technique in the NCEP global operational forecast system. Tellus, 60A , 6279.

    • Search Google Scholar
    • Export Citation
  • Wilks, D. S., 1995: Statistical Methods in the Atmospheric Sciences. Academic Press, 467 pp.

  • Wu, C-C., 2006: Targeted observation and data assimilation for tropical cyclone track prediction. Proc. Sixth Int. Workshop on Tropical Cyclones, San Jose, Costa Rica, WMO/CAS/WWW, 409–423.

    • Search Google Scholar
    • Export Citation
  • Wu, C-C., T-S. Huang, W-P. Huang, and K-H. Chou, 2003: A new look at the binary interaction: Potential vorticity diagnosis of he unusual southward movement of Typhoon Bopha (2000) and its interaction with Typhoon Saomai (2000). Mon. Wea. Rev., 131 , 12891300.

    • Search Google Scholar
    • Export Citation
  • Wu, C-C., and Coauthors, 2005: Dropwindsonde Observations for Typhoon Surveillance near the Taiwan Region (DOTSTAR): An overview. Bull. Amer. Meteor. Soc., 86 , 787790.

    • Search Google Scholar
    • Export Citation
  • Wu, C-C., J-H. Chen, P-H. Lin, and K-H. Chou, 2007a: Targeted observations of tropical cyclone movement based on the adjoint-derived sensitivity steering vector. J. Atmos. Sci., 64 , 26112626.

    • Search Google Scholar
    • Export Citation
  • Wu, C-C., K-H. Chou, P-H. Lin, S. D. Aberson, M. S. Peng, and T. Nakazawa, 2007b: The impact of dropwindsonde data on typhoon track forecasts in DOTSTAR. Wea. Forecasting, 22 , 11571176.

    • Search Google Scholar
    • Export Citation
  • Wu, C-C., S-G. Chen, J-H. Chen, K-H. Chou, and P-H. Lin, 2009: Interaction of Typhoon Shanshan (2006) with the midlatitude trough from both adjoint-derived sensitivity steering vector and potential vorticity perspectives. Mon. Wea. Rev., 137 , 852862.

    • Search Google Scholar
    • Export Citation
  • Yamaguchi, M., T. Iriguchi, T. Nakazawa, and C-C. Wu, 2009: An observing system experiment for Typhoon Conson (2004) using a singular vector method and DOTSTAR data. Mon. Wea. Rev., in press.

    • Search Google Scholar
    • Export Citation
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