• Beljaars, A. C. M., 1987. The measurement of gustiness at routine wind stations—A review. KNMI Scientific Rep. WR87-11.

  • Conder, M. R., , R. E. Peterson, , J. L. Schroeder, , and D. A. Smith, 1999. Comparison of hurricane wind data from Hurricane Bonnie: The Texas Tech Wind Engineering Mobile Instrumented Tower Experiment (WEMITE) and the NWS Wilmington ASOS. Proc. 13th Symp. on Boundary Layers and Turbulence, Dallas, TX, Amer. Meteor. Soc., 484–487.

  • Conder, M. R., , R. E. Peterson, , J. L. Schroeder, , and D. A. Smith, 2003. An analysis of wind characteristics during the ERODE experiment, April-May 2002. Preprints, 11th Int. Conf. on Wind Engineering, Lubbock, TX Int. Assoc. for Wind Engin. and Amer. Assoc. for Wind Engin., 2029–2036.

  • Deaves, D. M., 1981. Terrain-dependence of longitudinal R.M.S. velocities in the neutral atmosphere. J. Wind Eng. Ind. Aerodyn. 8:259274.

    • Search Google Scholar
    • Export Citation
  • Durst, C. S., 1960. Wind speeds over short periods of time. Meteor. Mag. 89:181187.

  • Gast, K. D., , and J. L. Schroeder, 2003. Supercell rear-flank downdraft as sampled in the 2003 Thunderstorm Outflow Experiment. Preprints, 11th Int. Conf. on Wind Engineering, Lubbock, TX, Int. Assoc. for Wind Engin. and Amer. Assoc. for Wind Engin., 2233–2240.

  • Krayer, W. R., , and R. D. Marshall, 1992. Gust factors applied to hurricane winds. Bull. Amer. Meteor. Soc. 73:613617.

  • Schroeder, J. L., , and D. A. Smith, 2003. Hurricane Bonnie wind flow characteristics as determined from WEMITE. J. Wind Eng. Ind. Aerodyn. 91:767789.

    • Search Google Scholar
    • Export Citation
  • Schroeder, J. L., , M. R. Conder, , and J. R. Howard, 2002. Additional insights into hurricane gust factors. Preprints, 25th Conf. on Hurricanes and Tropical Meteorology, San Diego, CA, Amer. Meteor. Soc., 39–40.

  • Sharma, R. N., , and P. J. Richards, 1999. A re-examination of the characteristics of tropical cyclone winds. J Wind Eng. Ind. Aerodyn. 83:2123.

    • Search Google Scholar
    • Export Citation
  • Sparks, P. R., , and Z. Huang, 1999. Wind speed characteristics in tropical cyclones. Wind Engineering into the 21st Century—Proceedings of the Tenth International Conference on Wind Engineering, A. Larson, G. L. Larose, and F. M. Livesey, Eds., A. A. Balkema, 343–350.

  • Wieringa, J., 1993. Representative roughness parameters for homogeneous terrain. Bound.-Layer Meteor. 63:323363.

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An Examination of Tropical and Extratropical Gust Factors and the Associated Wind Speed Histograms

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  • 1 Atmospheric Science Group, Texas Tech University, Lubbock, Texas
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Abstract

A gust factor, defined as the ratio between a peak wind gust and mean wind speed over a period of time, can be used along with other statistics to examine the structure of the wind. Gust factors are heavily dependent on upstream terrain conditions (roughness), but are also affected by transitional flow regimes (specifically, changes in terrain and the distance from the upstream terrain change to the measuring device), anemometer height, stability of the boundary layer, and, potentially, the presence of deep convection. Previous studies have yielded conflicting results regarding differences in gust factors that might exist between winds generated by tropical cyclones and those generated by extratropical systems. Using high-resolution wind speed data collected from both landfalling tropical cyclones and extratropical systems, two databases of wind characteristics were developed. Gust factors from tropical cyclone and extratropical winds were examined, summarized, and compared. Further analysis was conducted to examine and compare the characteristics of the associated tropical and extratropical wind speed histograms. As expected, the mean gust factor was found to increase with increasing upstream surface roughness. Some differences were observed between data from the tropical environment and the extratropical environment. Mean gust factors from the tropical regime were found to be higher than mean gust factors from the extratropical environment within each roughness regime and the wind speed histograms generated from data from the two environments indicated some differences.

Corresponding author address: Dr. Becca M. Paulsen, Texas Tech University, Department of Geosciences, Box 42101, Lubbock, TX 79409-2101. becca.paulsen@ttu.edu

Abstract

A gust factor, defined as the ratio between a peak wind gust and mean wind speed over a period of time, can be used along with other statistics to examine the structure of the wind. Gust factors are heavily dependent on upstream terrain conditions (roughness), but are also affected by transitional flow regimes (specifically, changes in terrain and the distance from the upstream terrain change to the measuring device), anemometer height, stability of the boundary layer, and, potentially, the presence of deep convection. Previous studies have yielded conflicting results regarding differences in gust factors that might exist between winds generated by tropical cyclones and those generated by extratropical systems. Using high-resolution wind speed data collected from both landfalling tropical cyclones and extratropical systems, two databases of wind characteristics were developed. Gust factors from tropical cyclone and extratropical winds were examined, summarized, and compared. Further analysis was conducted to examine and compare the characteristics of the associated tropical and extratropical wind speed histograms. As expected, the mean gust factor was found to increase with increasing upstream surface roughness. Some differences were observed between data from the tropical environment and the extratropical environment. Mean gust factors from the tropical regime were found to be higher than mean gust factors from the extratropical environment within each roughness regime and the wind speed histograms generated from data from the two environments indicated some differences.

Corresponding author address: Dr. Becca M. Paulsen, Texas Tech University, Department of Geosciences, Box 42101, Lubbock, TX 79409-2101. becca.paulsen@ttu.edu

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