HUNTSVILLE, Alabama -- The idea first occurred to Kevin Knupp after the deadly 1989 tornado that hit Airport Road.

Is it possible that an area's topography and surface characteristics can influence a tornado?

More than 20 years later, Knupp - a professor of atmospheric sciences at the University of Alabama in Huntsville - is continuing to advance that theory.

If true, it could give more insight into the phenomenon of tornadoes. But drawing firm conclusions on a tornado's influence is difficult because twisters are rare and, Knupp said, "the (scientific) process is slow."

For an area like North Alabama that's a tornado hotbed, though, Knupp has some intriguing observations.

In 1989, Knupp studied the aftermath of the Airport Road tornado and noticed damage lessened as it rose up the ridge that forms the western boundary of Jones Valley.

Upon descending that ridge, however, the damage quickly intensified - evidenced by the destruction of Jones Valley Elementary School.

"I thought 'Wow, what's going on here?' " Knupp said. "I continued mapping out the path and the next ridge was Huntsville Mountain. It did the same thing up there. There's a gated neighborhood at the top and there was minimal damage up there. As it went down the slope, it intensified again."

The theory gains more traction when considering the Anderson Hills subdivision in northwest Madison County. The subdivision is built largely on a downslope toward Alabama 53 and has sustained damage from tornadoes in 1995 and 2011.

"It certainly appeared to me there was an enhancement in the intensity in winds as it got into Anderson Hills and the same thing happened in 1995," Knupp said.

In wake of the record-setting April 27 tornadoes, Knupp is gearing up his research. He is working, in part, off a National Science Foundation RAPID (Rapid Response Research) grant to analyze the storm paths before natural vegetation begins to fade the damage.

The scientific data available from the storm can also lend insight, Knupp said, including high resolution aerial surveys that will "allow us to look at variations of intensity as a function of surface characteristics."

Knupp said scientific experiments over the years have indicated that surface characteristics - bodies of water and vegetation, for example - can influence the atmosphere. And topography - or changes in elevation - has been observed by Knupp to be able to alter a storm's intensity.

While Knupp said his theories on topography and surface characteristics haven't been universally embraced in the severe weather community, his hope is steady funding over the next three years will yield even more persuasive evidence.

Ultimately, the objective is to gain knowledge to perhaps even forecast tornadoes even more accurately.

"In general, (tornadoes) are relatively rare and it takes a lot of years of record to get something that is statistically meaningful and we're not quite there yet," Knupp said. "Patterns are starting to suggest things that we can form hypotheses on but just looking on locations of patterns, tornado frequency, intensity, path length, that data base is not extensive enough to really carry any scientific weight statistically yet.

"But we can use it to look at patterns and phenomenon and that's what we're doing now."

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