By Karin Heineman, Inside Science

When tornadoes hit, they are often quick, deadly and come without warning.

In 2013, more than fifty people were killed during tornadoes.

“We have tornadoes at daytime, we have tornadoes at night,” said Dev Niyogi, a climatologist at Purdue University in West Lafayette, Indiana.

Now, researchers at Purdue say there are certain areas that may be more likely than others to be hit by tornadoes.

“The region just around the city becomes a hotspot for where a tornado can occur,” explained Niyogi.

Scientists have identified tornado transition zones – places where the landscape suddenly changes – where tall buildings end and farmlands begin, or where a forest stops and flat land starts.

“Roughly…60 percent to two-thirds of the tornadoes form within a mile or within the five miles of the city,” said Niyogi.

Abrupt landscape changes – like from flat farms to big cities – can disrupt air patterns.  Air from these different zones mix together and can create severe storms and tornadoes.

The most vulnerable areas, according to Niyogi's research, are the areas just outside cities where the urban landscape turns into rural landscapes.

The research might explain why mobile home parks are often called tornado magnets, because they are typically located just outside city limits in open fields.

Modifying landscapes around these cities could help these areas be more tornado-resistant.

The study found tornado touchdowns in urban areas occur approximately 1 to 10 miles from the city center.



Citation: Olivia Kellner and Dev Niyogi, 2014: Land surface heterogeneity signature in tornado climatology? an illustrative analysis over indiana, 1950–2012. Earth Interact., 18, 1–32.
doi: http://dx.doi.org/10.1175/2013EI000548.1

Reprinted with permission from Inside Science, an editorially independent news product of the American Institute of Physics, a nonprofit organization dedicated to advancing, promoting and serving the physical sciences.

Karin Heineman is the executive producer of Inside Science TV. She has produced over 600 video news segments on science, technology, engineering and math in the past 13 years for Inside Science TV and its predecessor, Discoveries and Breakthroughs Inside Science.