Wednesday, May 30, 2018

Why was the water so clear last weekend?

So I went down to San Luis Pass (located between Galveston Island in Galveston County and Follett's Island in Brazoria County) to do some fishing over the Memorial Day weekend. It wasn't the best fishing trip ever: I caught a keeper black drum, but everything else I pulled up was either a stingray or a hardhead catfish.

The big story wasn't the fishing, though; it was the water. As anybody who's ever been to Galveston or Surfside Beach knows, the surf water in this part of Texas is usually very murky. That's because prevailing Gulf of Mexico currents carry muddy water from the Mississippi, Trinity and San Jacinto Rivers towards Galveston in a counter-clockwise direction.

However, last weekend this was not the case. The water was uncharacteristically clear and blue. I took a few pictures of the water from the Pass, on either side of the toll bridge linking Brazoria and Galveston Counties:




So why the uncharacteristically blue water? The Chronicle explains why:
Dr. Tom Linton, a marine biologist at Texas A&M University-Galveston, has a theory on why the water was so clear over the weekend. 
His theory is that Hurricane Alberto off the coast of Alabama in the Gulf of Mexico helped set up a gyre (a large system of rotating ocean currents) east of the Mississippi that began moving the water in a counter-clockwise direction. Hurricanes can go in a counter-clockwise direction. 
The competing, existing Gulf Stream created a gyre west of the Mississippi moving in a clockwise direction. 
"So you got these two gyres acting like floor sweepers, pulling in water from the west and the east," Linton said. 
Much clearer ocean water from the western side of the Gulf Stream, namely the Corpus Christi area and points south, was brought up and began striking the Galveston beach. It all goes to show that a hurricane in the Gulf no matter how big or small can have a very wide-reaching impact.
The murky water that this part of the coast normally receives might be ugly, but the nutrients it provides are essential for marine life. Which may have been why the fishing wasn't so great this past weekend.

In addition to the clear water, I also got a view of an impressive storm moving over Galveston County on Saturday evening:


All in all, it was an enjoyable Memorial Day weekend at the coast, featuring rarely-seen blue water. Now it's on to summer...

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