"The shape of the bedforms that make up the barrier system did not change a whole lot," said co-Principal Investigator (PI) John Goff of the Institute for Geophysics. "Where we might have expected to see significant erosion based on long-term history, not a lot happened nothing that ate into the shoreface."
"The sand largely took the blow," added co-PI Jamie Austin of the Institute for Geophysics. "Like a good barricade, the barrier system absorbed the significant blow, but held."
This was not the case in other storm-ravaged zones the Texas team has surveyed. When Hurricane Ike hit Galveston in 2008, the storm significantly disrupted the thin finer-grained sediment layer offshore, removing material underneath the shoreline in a way that exacerbated long-term problems of erosion.
Compared to Galveston, Long Island has a greater abundance of sand in its overall system. The storm churned up much of this sand and moved bedforms, but the scientists speculate that the greater abundance of sand helped the offshore barriers maintain their overall shape and integrity as erosional barriers.
Tempering this good news, the survey team also found evidence the storm brought new pollutants into the waters off Long Island. Heavy metals were detected in a layer of mud that the storm deposited offshore. Beth Christensen of Adelphi University traced the metals back to muds from the South Shore Estuary Reserve, which has a long history of pollution from industry and human habitation.
By this summer, natural forces had dispersed the layer of mud offshore, and the concentrations of toxins were not high enough to be an immediate concern, said Christensen.
"But if we continue to see more events like Sandy, we'll see the introduction of more and more muds from the estuary," said Christensen, "adding additional toxins to an already stressed system."
|Contact: J.B. Bird|
University of Texas at Austin