Hurricane Harvey shows how we underestimate flooding risks in coastal cities, scientists say
By Chelsea Harvey
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“Always when there is a hurricane, you have compounding effects of ocean flooding — surge — and terrestrial flooding,” said Amir AghaKouchak, an associate professor of hydrology and remote sensing at the University of California at Irvine. Harvey, he said, is a prime example of how these two factors work together to create the perfect storm, producing catastrophic coastal flooding when they occur at once. And now, he said, we need to pay more attention to the way these factors work together when we’re estimating flood risks for coastal regions — before disaster actually strikes.
Scientists tend to focus on one flood driver or another when conducting flood hazard assessments for any given area — evaluating either the risk of terrestrial flooding, which occurs inland as a result of excess precipitation and overflowing rivers, or of surging ocean waters. But in many coastal areas, where rivers run out to meet the sea, both factors play a major role in the risk of regional flooding. Focusing on only one or the other can run the risk of underestimating the likelihood of a major flood.
In a new study, a group of scientists from the University of California at Irvine, including AghaKouchak, and from the University of Salento in Lecce, Italy, have pointed out the importance of addressing both factors at once — and they’ve come up with a method that allows scientists to do so. Their findings were published Monday in the journal Proceedings of the National Academy of Sciences.
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