A&M-Galveston experts help with seaweed dilemma

A&M-Galveston experts help with seaweed dilemma

Credit: KHOU

The sand, the surf, and the seaweed, they’re all part of the Memorial Day 2014 experience on Galveston Island.

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by The Associated Press

The Associated Press

Posted on July 10, 2014 at 1:09 PM

GALVESTON, Texas (AP) -- The 8-by-10-inch piece of paper on the door of a small office deep within a building at Texas A&M University at Galveston describes Brandon Hill and James Frazier in the simplest of terms.
   
They are the "Seaweed Guys."
   
"This program has defined my career at Texas A&M," Hill said, as he stood in the hallway clad in a T-shirt decorated with an artist's rendition of a sargassum habitat.
   
As tons of seaweed continue to wash ashore on Galveston Island, a team of seven students - Hill and Frazier are two of them - has become the bearer of bad news.
   
The Galveston County Daily News (http://bit.ly/1oKsTw7 ) reports the students are the lifeblood of the Sargassum Early Advisory System, a NASA-funded project the university developed to study and report the movements of mats of sargassum seaweed from the Atlantic Ocean through the Caribbean Sea, into the Gulf of Mexico, and, ultimately, onto the Texas Coast.
   
Doctoral candidate Robert Webster leads the program, which is seeking to define the ways the sargassum moves through coastal waters and possibly answer why some years are worse than others in terms of seaweed landings.
   
Seaweed isn't a new issue, Webster said. It's not an invasive species that just appeared. The cycle has repeated itself annually for more than 4 million years, he said.
   
"We're intruding on their beaches and not vice versa," Webster said.
   
But despite the dependability of the landings, an explanation of how so much seaweed could make its way from the Sargasso Sea, an area of the Atlantic just off the U.S. East Coast, and end up here in such large amounts was lacking.
   
For a time, Webster said, the assumption was that seaweed somehow traveled past Florida, against a jet stream current. Another theory was that the warm waters of the Bay of Campeche in Mexico played a part.
   
But the theory Webster's team uses is that sargassum's travels are mainly motivated by wind.
   
"It seems like ocean current, to me, would have a much larger effect," Frazier said, because so much of the plant spends its time underwater, like an iceberg. "But wind has a much stronger effect on sargassum."
   
Using wind patterns, the team developed a system with which it can predict where and when sargassum will land.
   
Using photos taken from a pair of NASA satellites, which were originally purposed to take photos of crop conditions in the U.S. Midwest, the team looks for dark splotches indicating mats of seaweed in the blue seas and circles them. The circled mats are posted on the program's website, along with a prediction of when the next mat will land and how significant the landfall will be.
   
The satellites make a new pass every 16 days. So far this year, almost every new picture has shown more mats of seaweed.
   
"Anybody can see it," Hill said. "It's the prediction of where it's going to be that makes it difficult."
   
There's no set definition of how big a landing is, Webster said. This year's largest landings have caused the team to redefine its terminology.
   
What was a large landing when the project launched in 2010 might only be considered a medium landing by this year's standards. Among the team's projects is developing a way to consistently measure and characterize the size of a landing.
   
There's no single reason for why the 2014 landings seem so much heavier than in years past, Webster said. He theorizes that winds from the northwest have held the seaweed mats offshore, where they grow.
   
He also thinks that a gyre - a vortex in the middle of the Gulf - might have shifted west of its normal spot, allowing some of the sargassum that might normally have been pulled back out into the Atlantic to continue cycling in the Gulf.
   
"Sargassum is entering into that gyre and it's just going around and around," Webster said. "Some of it's coming back out and recycling."
   
The jury was still out on whether the gyre theory is scientifically correct, Webster said.
   
The program has been lauded by the Park Board of Trustees as a tool it uses to prepare for large landings, particularly in situations when the island's beach managers must call on extra equipment to help clear the beaches.
   
Webster said the team is working on a mobile application that would automate some of the detection and allow interested people - beach managers, anglers and beachgoers, for example - to check the status of mats more or less in real time.
   
"Essentially you can get the app and watch the movement as you would watch the movement of a thunderstorm," Webster said.
   
The volume of seaweed this year has provided plenty of data for the team to crunch, Webster said. But perhaps even more beneficial to the program is the amount of attention the sargassum has gotten this season.
   
The team recently began providing its forecasts not only for Texas locations, but for beaches in Louisiana and Alabama as well.
   
The seaweed is expected to keep coming, and the team's work to keep going, through the end of the summer. Recently, a 4-mile-long, 2-mile-wide mat was seen at Sabine Pass, but its likely headed to Louisiana.
   
Meanwhile, there has been one other adjustment that the team has had to make, Webster said.
   
"We've learned how to answer questions from the media."
   
___
   
Information from: The Galveston County Daily News, http://www.galvnews.com

(Copyright 2014 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.)

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