Editorial Type:
Article
Article Type:
Research Article

Regional Characterization of Tornado Activity

Robert J. Trapp Department of Earth, Atmospheric, and Planetary Sciences, and Purdue Climate Change Research Center, Purdue University, West Lafayette, Indiana

Search for other papers by Robert J. Trapp in
Current site
Google Scholar
PubMed Close
and
Harold E. Brooks National Severe Storms Laboratory, Norman, Oklahoma

Search for other papers by Harold E. Brooks in
Current site
Google Scholar
PubMed Close
Print Publication:
01 Mar 2013
DOI:
https://doi.org/10.1175/JAMC-D-12-0173.1
Page(s):
654–659
Restricted access

Abstract

In the United States, tornado activity of a given year is usually assessed in terms of the total number of human-reported tornadoes. Such assessments fail to account for the seldom-acknowledged fact that an active (or inactive) tornado year for the United States does not necessarily equate with activity (or inactivity) everywhere in the country. The authors illustrate this by comparing the geospatial tornado distributions from 1987, 2004, and 2011. Quantified in terms of the frequency of daily tornado occurrence (or “tornado days”), the high activity in the South Atlantic and upper Midwest regions was a major contributor to the record-setting number of tornadoes in 2004. The high activity in 2011 arose from significant tornado occurrences in the Southeast and lower Midwest. The authors also show that the uniqueness of the activity during these years can be determined by modeling the local statistical behavior of tornado days by a gamma distribution.

Corresponding author address: Robert J. Trapp, Dept. of Earth, Atmospheric, and Planetary Sciences, Purdue University, 550 Stadium Mall Dr., West Lafayette, IN 47907. E-mail: jtrapp@purdue.edu

Abstract

In the United States, tornado activity of a given year is usually assessed in terms of the total number of human-reported tornadoes. Such assessments fail to account for the seldom-acknowledged fact that an active (or inactive) tornado year for the United States does not necessarily equate with activity (or inactivity) everywhere in the country. The authors illustrate this by comparing the geospatial tornado distributions from 1987, 2004, and 2011. Quantified in terms of the frequency of daily tornado occurrence (or “tornado days”), the high activity in the South Atlantic and upper Midwest regions was a major contributor to the record-setting number of tornadoes in 2004. The high activity in 2011 arose from significant tornado occurrences in the Southeast and lower Midwest. The authors also show that the uniqueness of the activity during these years can be determined by modeling the local statistical behavior of tornado days by a gamma distribution.

Corresponding author address: Robert J. Trapp, Dept. of Earth, Atmospheric, and Planetary Sciences, Purdue University, 550 Stadium Mall Dr., West Lafayette, IN 47907. E-mail: jtrapp@purdue.edu
Save
Cover Journal of Applied Meteorology and Climatology
Journal of Applied Meteorology and Climatology

  • Blunden, J., D. S. Arndt, and M. O. Baringer, Eds., 2011: State of the climate in 2010. Bull. Amer. Meteor. Soc., 92, S1–S236.

  • Brooks, H. E., C. A. Doswell III, and M. P. Kay, 2003: Climatological estimates of local daily tornado probability for the United States. Wea. Forecasting, 18, 626–640.

    • Search Google Scholar
    • Export Citation

  • Changnon, S. A., Jr., 1982: Trends in tornado frequencies: Fact or fallacy? Preprints, 12th Conf. on Severe Local Storms, San Antonio, TX, Amer. Meteor. Soc., 42–44.

  • Diffenbaugh, N. S., R. J. Trapp, and H. E. Brooks, 2008: Challenges in identifying influences of global warming on tornado activity. Eos, Trans. Amer. Geophys. Union, 89, 553–554.

    • Search Google Scholar
    • Export Citation

  • Husak, G. J., J. Michaelsen, and C. Funk, 2006: Use of the gamma distribution to represent monthly rainfall in Africa for drought monitoring applications. Int. J. Climatol., 27, 935–944.

    • Search Google Scholar
    • Export Citation

  • Thom, H. C. S., 1958: A note on the gamma distribution. Mon. Wea. Rev., 86, 117–122.

  • Wilks, D. S., 2006: Statistical Methods in the Atmospheric Sciences. 2nd ed. Academic Press, 627 pp.

All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 287 88 11
PDF Downloads 245 69 6