Project models regional weather systems

Professors and students in the ECU Department of Geography, Planning and Environment are taking an in-depth look at weather patterns in the southeastern United States, thanks to a $450,000 grant from the National Science Foundation.

There are two main types of rainfall in the region – widespread rain from large systems such as fronts and tropical storms, and localized rain from isolated thunderstorms, said Rosana Ferreira, ECU associate professor of atmospheric science.

“When you just look at precipitation without splitting it into these two components, it looks like it’s just flat year-round,” she said. “What we’ve found in our previous research is that buried in there is a ramping up of the thunderstorm season in the summertime, and then ramping back down, much like what you see in a monsoon climate.”

During the next three years, Ferreira and Tom Rickenbach, associate professor of atmospheric science, will be studying the springtime transition between those two dominant patterns in an effort to better understand and predict long-term regional precipitation.

“What we’re trying to understand is how the meteorological conditions, like the wind patterns and the amount of energy from heating of the atmosphere, are changing in the springtime as we ramp up toward the turning on of this afternoon thunderstorm regime,” Rickenbach said. “And we want to pinpoint the timing of that.”

The hypothesis is that the transition happens quickly, over perhaps a couple of weeks in late May and early June, as the jet stream shifts north and the North Atlantic subtropical high begins to feed warm, moist air into the southeastern states. The study will use a detailed radar dataset from the National Centers of Environmental Information, a repository of climate data.

The data will be averaged into five-day periods to determine when the transition occurs each year.

“And then we’ll find out what happened meteorologically just before that onset occurred and what happens afterward,” Ferreira said.

Several graduate and undergraduate students will participate in the project, helping with the tracking of weather systems, modeling and analyzing data.