• Bergot, T., G. Hello, and A. Joly, 1999: Adaptive observations: Indent a feasibility study. Mon. Wea. Rev., 127 , 743765.

  • Bishop, C. H., 1993a: On the behavior of baroclinic waves undergoing horizontal deformation. I: The ‘RT’ phase diagram. Quart. J. Roy. Meteor. Soc., 119 , 221240.

    • Search Google Scholar
    • Export Citation
  • Bishop, C. H., . 1993b: On the behavior of baroclinic waves undergoing horizontal deformation. II: Error-bound amplification and Rossby wave diagnostics. Quart. J. Roy. Meteor. Soc., 119 , 241267.

    • Search Google Scholar
    • Export Citation
  • Bishop, C. H., and Z. Toth, 1999: Ensemble transformation and adaptive observations. J. Atmos. Sci., 56 , 17481765.

  • 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
  • Bloomfield, P., 1976: Fourier Analysis of Time Series: An Introduction. Wiley-Interscience, 258 pp.

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

  • Buizza, R., T. Petroliagis, T. N. Palmer, J. Barkmeijer, M. Hamrud, A. Hollingsworth, A. Simmons, and N. Weidi, 1998: Impact of model resolution and ensemble size on the performance of an ensemble prediction system. Quart. J. Roy. Meteor. Soc., 124 , 19351960.

    • Search Google Scholar
    • Export Citation
  • Chang, E. K. M., 1999: Wave packets and life cycles of troughs in the upper troposphere: Examples from the Southern Hemisphere summer season of 1984/85. Mon. Wea. Rev., 126 , 2550.

    • Search Google Scholar
    • Export Citation
  • Chang, E. K. M., and I. Orlanski, 1993: On the dynamics of storm tracks. J. Atmos. Sci., 50 , 9991015.

  • Chang, E. K. M., and D. B. Yu, 1999: Characteristics of wave packets in the upper troposphere. Part I: Northern Hemisphere winter. J. Atmos. Sci., 56 , 17081728.

    • Search Google Scholar
    • Export Citation
  • Charney, J. G., 1949: On a physical basis for numerical prediction of large-scale motions in the atmosphere. J. Meteor., 6 , 371385.

  • Emanuel, K. A., E. N. Lorenz, and R. E. Morss, 1996: Adaptive observations. Preprints, 11th Conf. on Numerical Weather Prediction, Norfolk, VA, Amer. Meteor. Soc., 67–69.

    • Search Google Scholar
    • Export Citation
  • Errico, R., T. Vukicevic, and K. Reader, 1993: Comparison of initial and lateral boundary condition sensitivity for a limited-area model. Tellus, 45 , 539577.

    • Search Google Scholar
    • Export Citation
  • Ertel, H., 1941: Die Unmöglichkeit einer exacten Wetterprognose auf Grund synoptischer Luftdruckkarten von Teilgebieten der Erde. Meteor. Z., 58 , 309313.

    • Search Google Scholar
    • Export Citation
  • Ertel, H., . 1944: Wettervorhersage als Randwertproblem. Meteor. Z., 61 , 181190.

  • Gelaro, R., R. H. Langland, G. D. Rohaly, and T. E. Rossmond, 1999: An assessment of the singular-vector approach to target observations using the FASTEX dataset. Quart. J. Roy. Meteor. Soc., 125 , 32993328.

    • Search Google Scholar
    • Export Citation
  • Hartmann, D. L., R. Buizza, and T. N. Palmer, 1995: Singular vectors: The effect of spatial scales on linear growth of disturbances. J. Atmos. Sci., 52 , 38853894.

    • Search Google Scholar
    • Export Citation
  • Hoskins, B. J., R. Buizza, and J. Badger, 2000: The nature of singular vector growth and structure. Quart. J. Roy. Meteor. Soc., 126 , 15651580.

    • Search Google Scholar
    • Export Citation
  • Hovmöller, E., 1949: The trough-and-ridge diagram. Tellus, 1 , 6266.

  • Langland, R. H., and G. D. Rohaly, 1996: Analysis error and adjoint sensitivity in the prediction of a North Atlantic frontal cyclone. Preprints, 11th Conf. on Numerical Weather Prediction, Norfolk, VA, Amer. Meteor. Soc., 150–152.

    • 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
  • Lorenz, E. N., and K. A. Emanuel, 1998: Optimal sites for supplementary weather observations: Simulations with a small model. J. Atmos. Sci., 55 , 633653.

    • Search Google Scholar
    • Export Citation
  • Majumdar, S. J., C. H. Bishop, I. Szunyogh, and Z. Toth, 2001: Can an ensemble transform Kalman filter predict reduction in forecast error variance produced by targeted observations? Q. J. Roy. Meteorol. Soc., 127 , 28032820.

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

    • Search Google Scholar
    • Export Citation
  • Miguez-Macho, G., and J. Paegle, 2001: Sensitivity of North American numerical weather prediction to initial state uncertainty in selected upstream subdomains. Mon. Wea. Rev., 129 , 20052022.

    • Search Google Scholar
    • Export Citation
  • Montani, A., A. J. Thorpe, R. Buizza, and P. Unden, 1999: Forecast skill of the ECMWF model using targeted observations during FASTEX. Quart. J. Roy. Meteor. Soc., 125 , 32193240.

    • Search Google Scholar
    • Export Citation
  • Morss, R. E., and K. A. Emanuel, 2002: Influence of added observations on analysis and forecast errors. Quart. J. Roy. Meteor. Soc., 128 , 285322.

    • Search Google Scholar
    • Export Citation
  • Morss, R. E., K. A. Emanuel, and C. Snyder, 2001: Idealized adaptive observation strategies for improving numerical weather prediction. J. Atmos. Sci., 58 , 210232.

    • Search Google Scholar
    • Export Citation
  • Orlanski, I., and J. Katzfey, 1991: The life cycle of a cyclone wave in the Southern Hemisphere. Part I: Eddy energy budget. J. Atmos. Sci., 48 , 19721998.

    • Search Google Scholar
    • Export Citation
  • Orlanski, I., and J. P. Sheldon, 1993: A case of downstream baroclinic development over western North America. Mon. Wea. Rev., 121 , 29292950.

    • 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
  • Parrish, D. F., and J. C. Derber, 1992: The National Meteorological Center's Spectral Statistical-Interpolation Analysis System. Mon. Wea. Rev., 120 , 17471763.

    • Search Google Scholar
    • Export Citation
  • Parrish, D. F., J. C. Derber, R. J. Purser, W-S. Wu, and Z-X. Pu, 1997: The NCEP global analysis system: Recent improvements and future plans. J. Meteor. Soc. Japan, 75 ((1B),) 359365.

    • Search Google Scholar
    • Export Citation
  • Pedlosky, J., 1987: Geophysical Fluid Dynamics. 2d ed. Springer-Verlag, 710 pp.

  • Persson, A., 2000: Synoptic-dynamic diagnosis of medium range weather forecast systems. Proc. Seminar on Diagnosis of Models and Data Assimilation Systems, Reading, United Kingdom, ECMWF, 123–137.

    • Search Google Scholar
    • Export Citation
  • Phillips, N. A., 1976: The impact of synoptic observing and analysis systems on flow pattern forecasts. Bull. Amer. Meteor. Soc., 57 , 12251240.

    • Search Google Scholar
    • Export Citation
  • Phillips, N. A., . 1990: Dispersion Processes in Large-Scale Weather Prediction. WMO-No. 700, 126 pp.

  • Pu, Z-X., and E. Kalnay, 1999: Targeting observations with the quasi-inverse linear and adjoint NCEP global models: Performance during FASTEX. Quart. J. Roy. Meteor. Soc., 125 , 33293337.

    • Search Google Scholar
    • Export Citation
  • Pu, Z-X., S. Lord, and E. Kalnay, 1998: Forecast sensitivity with dropwindsonde data and targeted observations. Tellus, 50A , 391410.

  • Rabier, F., P. Courtier, and O. Talagrand, 1992: An application of adjoint models to sensitivity analysis. Beitr. Phys. Atmos., 65 , 177192.

    • Search Google Scholar
    • Export Citation
  • Rabier, F., E. Klinker, P. Courtier, and A. Hollingsworth, 1996: Sensitivity of forecast errors to initial conditions. Quart. J. Roy. Meteor. Soc., 122 , 121150.

    • Search Google Scholar
    • Export Citation
  • Rossby, C-G., 1945: On the propagation of frequencies and energy in certain types of oceanic and atmospheric waves. J. Meteor., 2 , 187204.

    • Search Google Scholar
    • Export Citation
  • Rossby, C-G., . 1949: On the dispersion of planetary waves in a barotropic atmosphere. Tellus, 1 , 5458.

  • Snyder, C., 1996: Summary of an informal workshop on adaptive observations and FASTEX. Bull. Amer. Meteor. Soc., 77 , 953961.

  • Swanson, K., and R. T. Pierrehumbert, 1994: Nonlinear wave packet evolution on a baroclinically unstable jet. J. Atmos. Sci., 51 , 384396.

    • Search Google Scholar
    • Export Citation
  • Szunyogh, I., E. Kalnay, and Z. Toth, 1997: A comparison of Lyapunov and optimal vectors in a low-resolution GCM. Tellus, 49A , 200227.

    • Search Google Scholar
    • Export Citation
  • Szunyogh, I., Z. Toth, K. A. Emanuel, C. H. Bishop, C. Snyder, R. E. Morss, J. Woolen, and T. Marchok, 1999a: Ensemble-based targeting experiments during FASTEX: The effect of dropsonde data from the Lear jet. Quart. J. Roy. Meteor. Soc., 125 , 31893218.

    • Search Google Scholar
    • Export Citation
  • Szunyogh, I., Z. Toth, S. J. Majumdar, R. E. Morss, C. H. Bishop, and S. Lord, 1999b: Ensemble-based targeted observations during NORPEX. Preprints, Third Symp. on Integrating Observing Systems, Amer. Meteor. Soc., Dallas, TX, 74–77.

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

  • Toth, Z., and E. Kalnay, . 1997: Ensemble forecasting at NCEP and the breeding method. Mon. Wea. Rev., 125 , 32973319.

  • Toth, Z., E. Kalnay, S. M. Tracton, R. Wobus, and J. Irwin, 1997: A synoptic evaluation of the NCEP ensemble. Wea. Forecasting, 12 , 140153.

    • Search Google Scholar
    • Export Citation
  • Toth, Z., and Coauthors. 2000: Targeted observations at NCEP: Toward an operational implementation. Preprints, Fourth Symp. on Integrating Observing Systems, Long Beach, CA, Amer. Meteor. Soc., 186–193.

    • Search Google Scholar
    • Export Citation
  • Toth, Z., I. Szunyogh, C. Bishop, S. Majumdar, R. Morss, and S. Lord, 2001: On the use of targeted observations in operational weather prediction. Preprints, Fifth Symp. on Integrating Observing Systems, Albuquerque, NM, Amer. Meteor. Soc., 72–79.

    • Search Google Scholar
    • Export Citation
  • Whitaker, J. S., and R. M. Dole, 1995: Organization of storm tracks in zonally varying flows. J. Atmos. Sci., 52 , 11781191.

  • Yeh, T., 1949: On energy dispersion in the atmosphere. J. Meteor., 6 , 116.

All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 0 0 0
PDF Downloads 1 1 1

Propagation of the Effect of Targeted Observations: The 2000 Winter Storm Reconnaissance Program

View More View Less
  • 1 UCAR Visiting Scientist, NCEP, Camp Springs, Maryland
  • | 2 SAIC, NCEP, Camp Springs, Maryland
  • | 3 Institute for Physical Science and Technology, University of Maryland, College Park, Maryland
  • | 4 Department of Meteorology, The Pennsylvania State University, University Park, Pennsylvania
  • | 5 European Centre for Medium-Range Weather Forecasts, Shinfield Park, Reading, United Kingdom
Restricted access

Abstract

The propagation of the effect of targeted observations in numerical weather forecasts is investigated, based on results from the 2000 Winter Storm Reconnaissance (WSR00) program. In this field program, nearly 300 dropsondes were released adaptively at selected locations over the northeast Pacific on 12 separate flight days with the aim of reducing the risk of major failures in severe winter storm forecasts over the United States. The data impact was assessed by analysis–forecast experiments carried out with the T62 horizontal resolution, 28-level version of the operational global Medium Range Forecast system of the National Centers for Environmental Prediction.

In some cases, storms that reached the West Coast or Alaska were observed in an earlier phase of their development, while at other times the goal was to improve the prediction of storms that formed far downstream of the targeted region. Changes in the forecasts were the largest when landfalling systems were targeted and the baroclinic energy conversion was strong in the targeted region.

As expected from the experience accumulated during the 1999 Winter Storm Reconnaissance (WSR99) program, downstream baroclinic development played a major role in propagating the influence of the targeted data over North America. The results also show, however, that predicting the location of significant changes due to the targeted data in the forecasts can be difficult in the presence of a nonzonal large-scale flow. The strong zonal variations in the large-scale flow over the northeast Pacific during WSR00 did not reduce the positive forecast effects of the targeted data. On the contrary, the overall impact of the dropsonde data was more positive than during WSR99, when the large-scale flow was dominantly zonal on the flight days. This can be attributed to the improved prediction of the large-scale flow that led to additional improvements in the prediction of the synoptic-scale waves.

Corresponding author address: Dr. I. Szunyogh, Institute for Physical Science and Technology, University of Maryland, Computer and Space Sciences Bldg., College Park, MD 20742-2431. Email: szunyogh@ipst.umd.edu

Abstract

The propagation of the effect of targeted observations in numerical weather forecasts is investigated, based on results from the 2000 Winter Storm Reconnaissance (WSR00) program. In this field program, nearly 300 dropsondes were released adaptively at selected locations over the northeast Pacific on 12 separate flight days with the aim of reducing the risk of major failures in severe winter storm forecasts over the United States. The data impact was assessed by analysis–forecast experiments carried out with the T62 horizontal resolution, 28-level version of the operational global Medium Range Forecast system of the National Centers for Environmental Prediction.

In some cases, storms that reached the West Coast or Alaska were observed in an earlier phase of their development, while at other times the goal was to improve the prediction of storms that formed far downstream of the targeted region. Changes in the forecasts were the largest when landfalling systems were targeted and the baroclinic energy conversion was strong in the targeted region.

As expected from the experience accumulated during the 1999 Winter Storm Reconnaissance (WSR99) program, downstream baroclinic development played a major role in propagating the influence of the targeted data over North America. The results also show, however, that predicting the location of significant changes due to the targeted data in the forecasts can be difficult in the presence of a nonzonal large-scale flow. The strong zonal variations in the large-scale flow over the northeast Pacific during WSR00 did not reduce the positive forecast effects of the targeted data. On the contrary, the overall impact of the dropsonde data was more positive than during WSR99, when the large-scale flow was dominantly zonal on the flight days. This can be attributed to the improved prediction of the large-scale flow that led to additional improvements in the prediction of the synoptic-scale waves.

Corresponding author address: Dr. I. Szunyogh, Institute for Physical Science and Technology, University of Maryland, Computer and Space Sciences Bldg., College Park, MD 20742-2431. Email: szunyogh@ipst.umd.edu

Save