© Matt Coker
Emerging pattern: fewer tornado days in U.S. - but more tornados!
A trio of researches with the U.S.'s National Oceanic and Atmospheric Administration (NOAA) has found that though there are fewer total days per year when tornados occur in the U.S., the number that occur on days when there are tornados has increased over the past couple of decades
. In their paper published in the journal Science
, Harold Brooks, Gregory Carbin and Patrick Marsh describe how they studied weather data over the past half century and what they found when looking for trends.
Tornados happen in many places, but because of its unique geography, the U.S. has more than any other country - mainly due to the lack of a large mountain dividing east and west. There has been speculation recently, that global warming
is causing more tornados to occur - though it has also been suggested it only seems that way because of how quickly information about tornadic events disseminates in the modern era. The trio at NOAA decided to let hard facts tell the story. They collected weather data
from the national storm database, which goes back to 1954, to see if they could coax out any patterns (they only included tornados at least as strong as an F1).