Featured Research

from universities, journals, and other organizations

Large dead zone forming in the Gulf

Date:
June 27, 2013
Source:
Texas A&M University
Summary:
Ocean experts had predicted a large “dead zone” area in the Gulf of Mexico this year, and according to the results from a researcher just back from studying the region, those predictions appear to be right on target.

Texas A&M professor Steve DiMarco taking water samples.
Credit: Texas A&M University

Ocean experts had predicted a large "dead zone" area in the Gulf of Mexico this year, and according to the results from a Texas A&M University researcher just back from studying the region, those predictions appear to be right on target.

Steve DiMarco, professor of oceanography and one of the world's leading experts on the dead zone, says he and a Texas A&M team surveyed areas off the Texas-Louisiana coast last week and found large areas of oxygen-depleted water -- an area covering roughly 3,100 square miles, or about the size of Delaware and Rhode Island combined.

"We found hypoxia (oxygen-depleted water) just about everywhere we looked," DiMarco reports.

"The most intense area is where you would expect it -- off the Louisiana coast south of Atchafalaya Bay and Grande Isle, La. But we also found significant amounts off High Island and near Galveston. The farther south we went, the less we found hypoxia in the water column, but we still found plenty of depleted oxygen waters up to just west of Freeport.

"There is no doubt there is a lot of hypoxia in the Gulf this year."

Hypoxia occurs when oxygen levels in seawater drop to dangerously low levels, and persistent hypoxia can potentially result in fish kills and harm marine life, thereby creating a "dead zone" in that particular area.

Such low levels of oxygen are believed to be caused by nutrient pollution from farm fertilizers as they empty into rivers such as the Mississippi and eventually into the Gulf, or by soil erosion or discharge from sewage treatment plants. The size of the zone has been shown to be influenced by the nutrient runoff, volume of freshwater discharged, and prevailing winds, which controls the freshwater river plume's movement.

The Mississippi is the largest river in the United States, draining 40 percent of the land area of the country. It also accounts for almost 90 percent of the freshwater runoff into the Gulf of Mexico.

Last year, with much of the Midwest suffering through its worst drought in 100 years, the dead zone measured only 1,580 square miles.

DiMarco's research on the dead zone is supported by the National Oceanic and Atmospheric Association (NOAA), as part of its long-term commitment to advancing the science to inform management practices aimed at mitigating the hypoxic zone.

"While we await additional data from the entire summer, these early findings start to validate our prediction that we could see one of the largest dead zones ever in the Gulf of Mexico this July," said Robert Magnien, Ph.D., center director at NOAA's National Centers for Coastal Ocean Science.

"This is further confirmation of the link between upstream nutrient management decisions and the critical habitats and living resources in the Gulf."

DiMarco has made 28 research trips to investigate the dead zone since 2003. His cruise this year carried 10 investigators from Texas A&M and Texas A&M at Galveston and included two research scientists, Matthew Howard and Ruth Perry, five graduate students, Laura Harred, Jordan Young, Yan Zhao, Heather Zimmerle, and Nicole Zuck, and two marine technicians, Eddie Webb and Andrew Dancer (Geochemical and Environmental Research Group). On shore investigators include Lisa Campbell, Wilford Gardner, Shari Yvon-Lewis, and Ethan Grossman , all from Texas A&M, and Antonietta Quigg from Texas A&M-Galveston.

DiMarco says the size of the dead zone off coastal Louisiana has been routinely monitored since 1985. Previous research has also shown that nitrogen levels in the Gulf related to human activities have tripled over the past 50 years.


Story Source:

The above story is based on materials provided by Texas A&M University. Note: Materials may be edited for content and length.


Cite This Page:

Texas A&M University. "Large dead zone forming in the Gulf." ScienceDaily. ScienceDaily, 27 June 2013. <www.sciencedaily.com/releases/2013/06/130627161358.htm>.
Texas A&M University. (2013, June 27). Large dead zone forming in the Gulf. ScienceDaily. Retrieved September 1, 2014 from www.sciencedaily.com/releases/2013/06/130627161358.htm
Texas A&M University. "Large dead zone forming in the Gulf." ScienceDaily. www.sciencedaily.com/releases/2013/06/130627161358.htm (accessed September 1, 2014).

Share This




More Earth & Climate News

Monday, September 1, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Iceland Lowers Aviation Alert on Volcano

Iceland Lowers Aviation Alert on Volcano

AFP (Sep. 1, 2014) Iceland has lowered its aviation alert on its largest volcano after a fresh eruption on a nearby lava field prompted authorities to enforce a flight ban for several hours. Duration: 01:07 Video provided by AFP
Powered by NewsLook.com
Lightning Hurts 3 on NYC Beach

Lightning Hurts 3 on NYC Beach

AP (Sep. 1, 2014) A lightning strike injured three people on a New York City beach on Sunday. The storms also delayed flights and interrupted play at the US Open tennis tournament. (Sept. 1) Video provided by AP
Powered by NewsLook.com
Thailand Totters Towards Waste Crisis

Thailand Totters Towards Waste Crisis

AFP (Sep. 1, 2014) Fears are mounting in Bangkok that poor planning and lax law enforcement are tipping Thailand towards a waste crisis. Duration: 01:21 Video provided by AFP
Powered by NewsLook.com
Melting Ice Shelves Drive Rapid Antarctic Sea Level Rise

Melting Ice Shelves Drive Rapid Antarctic Sea Level Rise

Newsy (Sep. 1, 2014) A study of almost 20 years' worth of satellite images shows Antarctic sea levels are on the rise as ice shelves continue to melt. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins