Read More: Scientific American
Scientists who combined an on-the-ground look at stream gauge data and an above-the-ground view from satellites have determined that as the Earth warms, the threat of flooding is growing in the northern half of the United States. The research from the University of Iowa, published recently in the journal Geophysical Research Letters, found that shifting rainfall patterns and the amount of water in the ground are likely causes for the changes. The work fed off research published in 2015 that looked at stream gauges in the central United States, said Gabriele Villarini, an associate professor in civil and environmental engineering at the university and a co-author of the new paper with Louise Slater. His earlier research showed limited evidence of significant changes in the magnitude of floods, but strong evidence pointing toward an increasing frequency of flooding. “Now that we have detected the changes, can we try to identify what the potential major drivers of these changes were?” he said. “That’s why we looked at overall wetness and precipitation as a way of trying to explain this spatially distinct patterns that we saw from the data.” Their research also found that the South and West are experiencing decreasing flood risk, an unsurprising finding, he said, given that those regions have experienced both recent and long-standing drought, and that there is less water stored underground. Their findings, which also aim to shift how flood risks are communicated, could have fundamental implications for water managers, agricultural interests and the people who live in flood-prone regions.