Jun 27, 2016

Variability of tornado occurrence over the continental United States since 1950

Guo, Li, Wang, Kaicun, Bluestein, Howard B.
Journal of Geophysical Research: Atmospheres
  • States that concern has arisen regarding the effect of a changing climate on tornadoes in the U.S.
  • Describes a recent study that claimed the temporal variability of tornado occurrence over the continental U.S. has increased since the 1970s
    • Utilizes the term "temporal variability" to refer to the instability of tornado frequency
  • States that said study treated the continental U.S. as a whole, ignoring regional differences in tornado climatology
  • Examines 64 year tornado records (1950–2013) to determine the long-term trend of tornado temporal variability in each continental U.S. state
  • Finds that only one third of the continental area or three out of 10 contiguous states displayed a significantly increasing trend
  • Finds that the other two-thirds area showed a decreasing or a near-zero trend in tornado temporal variability
  • Results also show that, unlike the temporal variability alone, the combined spatial-temporal variability of U.S. tornado occurrence has remained nearly constant since 1950
  • Results refine the claim of previous study and can be helpful for local mitigation efforts toward future tornado risks