Increased variability of tornado occurrence in the United States
Tornadoes clustering in greater numbers
Will global warming cause more tornadoes? If so, that has not happened yet. Brooks et al. compiled data on the occurrence of tornadoes in the United States between 1954 and 2013 to determine if and how tornado numbers have changed. Although the authors saw no clear trend in the annual number of tornadoes, they did see more clusters of tornadoes since the 1970s. In other words, there has been a decrease in the number of days per year with tornadoes but an increase in the number of days with multiple tornadoes. Why this clustering effect has occurred is not clear.
Science, this issue p. 349
Abstract
Whether or not climate change has had an impact on the occurrence of tornadoes in the United States has become a question of high public and scientific interest, but changes in how tornadoes are reported have made it difficult to answer it convincingly. We show that, excluding the weakest tornadoes, the mean annual number of tornadoes has remained relatively constant, but their variability of occurrence has increased since the 1970s. This is due to a decrease in the number of days per year with tornadoes combined with an increase in days with many tornadoes, leading to greater variability on annual and monthly time scales and changes in the timing of the start of the tornado season.
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Supplementary Material
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Table S1
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References and Notes
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Science
Volume 346 | Issue 6207
17 October 2014
17 October 2014
Copyright
Copyright © 2014, American Association for the Advancement of Science.
Submission history
Received: 16 June 2014
Accepted: 11 September 2014
Published in print: 17 October 2014
Acknowledgments
The scientific results and conclusions, as well as any views or opinions expressed herein, are those of the authors and do not necessarily reflect the views of NOAA or the Department of Commerce. G.W.C. carried out quality control on the dataset, H.E.B. performed primary analyses, and P.T.M. performed additional analyses and prepared figures.
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- More tornadoes in the most extreme U.S. tornado outbreaks, Science, 354, 6318, (1419-1423), (2021)./doi/10.1126/science.aah7393
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