John Goff describes how Hurricane Ike eroded Gulf Coast islands

He said the most erosion from this 2008 hurricane occurred when the hurricane subsided, as water rushed out of an overflowing Galveston Bay, back into the Gulf of Mexico.

Geophysicist John Goff has studied some of the slim barrier islands running parallel to the Texas coast – including Galveston Island. He said those islands were badly damaged in September of 2008 by Hurricane Ike, which made landfall near the city of Galveston.

John Goff: There was a tremendous loss of sand, and sand is the critical component to maintaining the health of the system.

Goff mapped the seafloor between barrier islands, before and after Hurricane Ike. He said the most erosion occurred when the hurricane subsided, as water rushed out of an overflowing Galveston Bay, back into the Gulf of Mexico.

John Goff: The back surge is very important. That, we found, was a very, very strong force. It moved a lot of sediment and eroded a lot of the sand. Those sands are critical to maintaining the beach barrier system. And without it, once you reduce it, it’s very hard to get it back.

That’s why, Goff said, his research could be helpful for cities like Galveston – places where hurricanes are likely. Galveston sits on a barrier island. Hurricane Ike sent a storm surge over the city that reached 20 feet – over six meters – in some places, before rushing back into the Gulf of Mexico. Goff said it’s possible to replenish Galveston Island’s lost sand. But, he said, it’s expensive.

To date, the city still has not fully recovered, and part of its human population has not returned.

Our thanks to:
John Goff
Senior Research Scientist
Institute for Geophysics
The Jackson School of Geosciences
Austin, TX

Photo Credit: Tzuyu Jennifer

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