KU researchers use satellite technology to prevent future Dust Bowls

LAWRENCE -- Other than hoping for rain, not much can be done about the current drought.

Still, researchers at the University of Kansas are working hard to prevent something even worse -- another Dust Bowl.

Scientists in the Kansas Applied Remote Sensing Program at KU have developed a new technique that compares multiple dates of satellite imagery of the Great Plains using the Normalized Difference Vegetation Index, which measures the amount of green vegetation on Earth.

By keeping a close eye on the yearly pattern of vegetation growth, death and regrowth, they can spot the places that are most prone to chronic drought conditions. If those areas are neglected over time, they can easily lead to a scenario like the Dust Bowl of the 1930s.

The research team at KARS, led by Mark Jakubauskas, focused on the southern Great Plains, including southwest Kansas, for the purposes of their study. Through remote sensing technology, satellites scan the earth's surface and record reflected light. Green vegetation on the surface reflects that light back up to the satellite, giving a very detailed indication of the presence and "greenness" of the vegetation below.

By taking these readings every two weeks the scientists can chart the yearlong cycle of when and how much greening occurs in an area as small as 250 acres. They also can spot changes from year to year that demonstrate how an area might become more prone to chronic drought, causing less vegetation to turn green over time.

As a result, the scientists found that the seasonal changes in vegetation condition measured by the greenness index followed a curve that was similar to other events in nature.

"We were amazed that we could use the same mathematical technique to analyze seasonal greenness patterns as we could a heart rhythm or temperature ranges or tides," Jakubauskas said.

And just like a cardiologist monitoring a heart rhythm, Jakubauskas and the other KARS scientists are always on the lookout for danger signs.

"Just as a doctor can detect heart disease in a patient and potentially prevent a fatal heart attack, we want to identify areas in the Great Plains that aren't stable," he said. "These unstable areas could benefit from improved land management techniques in order to prevent another Dust Bowl."

The innovative technique has already been recognized by the nation's largest scientific society for remote sensing researchers. The study that resulted from this research recently was named best paper in Image Analysis and Interpretation for 2001 by the American Society for Photogrammetry and Remote Sensing.

Prior to developing this technique, there really wasn't an accurate way to look at such a large sampling area with such a detailed eye, Jakubauskas said.

"This method presents so many new possibilities to explore that it's like landing on the New World. We have this analysis technique that is generating more questions than it answers right now," he said.

Next up for the researchers is to combine their technique with climate data from the region to see how much precipitation and moisture -- as compared to land management or soil quality -- affect the greening curve.

Before they can do that, however, they will need additional funding. The project recently completed the final year of a three-year $300,000 grant from the South Central region of the National Institutes for Global Environmental Change -- a division of the Department of Energy.

Jakubauskas said additional funding was crucial because the scientists are very close to making further breakthroughs with their innovative research.

"I think we could probably spend the next 10 years or maybe even the rest of our careers fully exploring this," he said.