Iowa City Press-Citizen: UI Teams Up with NASA to Better Predict Precipitation Via Satellites

Thursday, June 13, 2013
A large crane drops the NASA Polarimetric antenna into place in Eastern Iowa near Waterloo for the Iowa Flood Studies campaign, which started May 1 and finishes Saturday.
 

A large crane drops the NASA Polarimetric antenna into place in Eastern Iowa near Waterloo for the Iowa Flood Studies campaign, which started May 1 and finishes Saturday. / Aneta Goska / Iowa Flood Center

As NASA gears up for a worldwide campaign to predict precipitation using satellites, it’s enlisting University of Iowa flood experts to determine whether its plan will work.

NASA’s experts have been working with UI’s Iowa Flood Center since May 1 to collect ground data across Iowa — chosen for its tendency to flood — that ultimately will be paired with satellite data collected through NASA’s Global Precipitation Measurement (GPM) in an effort to take flood forecasting to a new level.

The researchers are measuring a number of characteristics in Iowa, such as the proportion of rainfall that does and does not infiltrate the ground — a factor determined by land use and soil properties — as well as the ability of river networks to determine the timing and extent of flooding, Witold Krajewski, director of the Iowa Flood Center, said in a video conference Tuesday afternoon at UI.

Iowa was a natural host for the so-called Iowa Flood Studies campaign, which wraps up Saturday, because of the amount of flooding the state has experienced over the years, Krajewski said. In 2008, flooding cost the state close to $10 billion and at the time ranked as the fifth costliest natural disaster in U.S. history, he said.

Since the flood center was established in 2009, it has improved water monitoring by developing a complex online mapping system that shows where flooding will occur in Iowa communities if the water reaches certain levels.

“Even now, as we’re in the middle of this campaign, we’ve got flooding over the last month across Iowa, including in Iowa City, where I’m speaking from,” Krajewski said. “Still, the rivers and streams are running high, which makes for a good case for a scientific study, but I wish the flooding would stop. We’ve had enough.”

NASA plans to launch its network of international satellites in February 2014. The satellites will provide rain and snow observations from space every three hours, data that NASA’s current technology provides only twice daily, said Walt Petersen, a NASA scientist currently working on the Iowa Flood Studies campaign from a base in the city of Traer just south of Waterloo.

The idea is to more accurately measure precipitation and predict flooding so that decision-makers can better prepare, Petersen said. Although they cause considerable damage in Iowa, floods have the largest impact on underdeveloped countries, he said.

“Tens of thousands of people annually lose their lives to flooding, the majority of that in the developing world,” Petersen said.

A major reason is because many areas don’t have the ability to provide warning to residents, something GPM is expected to help with, he said.

NASA is using advanced precipitation radar technology stretching roughly from Waterloo to Iowa City that scans the atmosphere and retrieves the size, shape and distribution of raindrops and rainclouds. Researchers also have installed a network of rain gauges in river basins across Iowa that will provide reference points for the radar. Once all of the information can be contrasted against data collected from space, it will provide the clearest predictions yet, Petersen said.

“It’s a local study with global applications,” he said.

Iowa has provided a range of weather for NASA’s researchers, Petersen said. When scientists first arrived to sample rain, they found themselves in the midst of a historic snowstorm, which was a great opportunity for data collection, he said.

When NASA began contemplating whether to host the project in Iowa, the state was experiencing a severe drought, Krajewski said. By contrast, scientists have seen very few days without rain in the past five or six weeks, he said.

“This has been an extremely busy campaign,” Krajewski said.