In 2010, Scott Rowe spent his spring break sandbagging in Fargo, N.D., to help protect the city from floodwaters. At the time, he was an undergraduate studying atmospheric sciences at the University of North Dakota. The sandbagging effort was successful, and Rowe says he was intrigued to see how the community came together to respond to the flood threat. “It was fun. We were overfed, almost,” Rowe says, remembering the outpouring of gratitude and food for the volunteers.
He also came away with a serious interest in hydrology, which brought him to IIHR and the Iowa Flood Center for graduate studies. But Rowe has been interested in weather for a long time. He spent the first 12 years of his life in Tornado Alley. Since Texas homes rarely have basements, Rowe took shelter in the bathtub when tornado warnings were issued, sometimes with his bike helmet on for extra protection.
From then on, Rowe was fascinated by weather. He is now working on a master’s degree at IIHR under the supervision of his advisor, Gabriele Villarini. Together, they are developing a statewide climate forecast for Iowa to offer a basic idea of what precipitation can be expected in the season ahead. Their forecasts will be basic by design, Rowe explains, and limited to predicting whether precipitation will be average, above average, or below average. “It’s difficult to even make an exact precipitation forecast for 24 hours for now,” he says. Compound that over an entire season, Rowe says, and that error can become “ginormous.” With that said, depending on the success of the new system, Rowe and Villarini may attempt more quantitative statements in the future.
Rowe is analyzing Iowa’s climate data to rank the average monthly temperature and precipitation back to 1950. By correlating the atmospheric anomalies associated with the wettest and driest months, Rowe says, they’re able to use a number of existing climate models to develop a long-lead climate forecast.
Once Rowe and Villarini have a few forecasts under their belt, they’ll evaluate the accuracy by comparing their prediction to what actually happened. That information will be vital to improving the predictions, Rowe explains. “A bad forecast model is of no use to us.”
Although Rowe has no interest in broadcasting, he enjoys weather forecasting and hopes to find a job with the National Weather Service or some other forecasting agency after graduation. He may even find his way back to North Dakota, where he first got his feet wet in weather forecasting.
“Our vision is a paradigm shift in water-level observation and stream-flow modeling,” explains IIHR Research Engineer Ricardo Mantilla. With IFC Director Witold Krajewski, Mantilla has designed a hybrid flood forecasting system that combines real-time water level observations with an advanced mathematical hydrologic model. “This system gives us the best of both worlds,” Mantilla says.
IFC researchers developed an affordable bridge-mounted electronic stream-stage sensor that uses sonar to measure the distance from the sensor to the water’s surface. Researchers deployed 20 of these sensors within the Squaw Creek basin in Central Iowa, upstream from its junction with the South Skunk River. The automated sensors measure stream water height and transmit the information automatically to the Iowa Flood Center, where it is available online through the Iowa Flood Information System.
The data these sensors collect are combined with a state-of-the-art mathematical model that uses detailed digital elevation models of the landscape, NEXRAD rainfall, and soils and land use data to accurately represent flow through the watershed. Sensor-collected data is used to continuously refine the hydrologic model’s reliability until it can provide dependable predictions at locations where no sensor is present.
“By the end of the two-year project, the system will provide accurate predictions of flooding potential for each and every road/stream intersection in the basin,” Mantilla says. “It will establish the basis for a customized real-time flood and flash-flood forecasting system for roads and bridges across the entire state — thus increasing public safety.”
The Iowa Flood Center is part of IIHR—Hydroscience & Engineering, a research institute based at the University of Iowa’s College of Engineering. The IFC was established in 2009 to provide accurate, state-of-the-science-based information to help Iowans better understand their flood risks. It is the nation’s first academic center devoted solely to the study of floods.