Navigation Links
Smaller than expected, but severe, dead zone in Gulf of Mexico
Date:7/27/2009

NOAA-supported scientists, led by Nancy Rabalais, Ph.D., from the Louisiana Universities Marine Consortium (LUMCON), found the size of this year's Gulf of Mexico dead zone to be smaller than forecasted, measuring 3,000 square miles. However the dead zone, which is usually limited to water just above the sea floor, was severe where it did occur, extending closer to the water surface then in most years.

Earlier this summer, NOAA-sponsored forecast models developed by R. Eugene Turner, Ph. D. of Louisiana State University and Donald Scavia, Ph.D. of the University of Michigan, predicted a larger than normal dead zone area of between 7,450 8,456 square miles. The forecast was driven primarily by the high nitrate loads and high freshwater flows from the Mississippi and Atchafalaya rivers in spring 2009 as measured by the U.S. Geological Survey.

Rabalais believes the smaller than expected dead zone is due to unusual weather patterns that re-oxygenated the waters, among other factors.

"The winds and waves were high in the area to the west of the Atchafalaya River delta and likely mixed oxygen into these shallower waters prior to the cruise, thus reducing the area of the zone in that region," said Rabalais. "The variability we see within each summer highlights the continuing need for multiple surveys to measure the size of the dead zone in a more systematic fashion."

"The results of the 2009 cruise at first glance are hopeful, but the smaller than expected area of hypoxia appears to be related to short-term weather patterns before measurements were taken, not a reduction in the underlying cause, excessive nutrient runoff." said Robert Magnien, PhD., director of NOAA's Center for Sponsored Coastal Ocean Research. "The smaller area measured by this one cruise, therefore, does not represent a trend and in no way diminishes the need for a harder look at efforts to reduce nutrient runoff."

The average size of the dead zone over the past five years, including this cruise, is now 6,000 square miles. The interagency Gulf of Mexico/Mississippi River Watershed Nutrient Task Force has a goal to reduce or make significant progress toward reducing this dead zone average to 2,000 square miles or less by 2015. The Task Force uses a five year average due to relatively high interannual variability.

The dead zone is fueled by nutrient runoff, principally from agricultural activity, which stimulates an overgrowth of algae that sinks, decomposes, and consumes most of the life-giving oxygen supply in the water. The Gulf of Mexico dead zone is of particular concern because it threatens valuable commercial and recreational Gulf fisheries that generate about $2.8 billion annually.

The models used to forecast the area of the dead zone are constructed for understanding the important underlying causes to inform long-term management decisions, but they do not include short-term variability due to weather patterns.

Prior to the LUMCON cruise, NOAA's Southeast Monitoring and Assessment Program (SEAMAP) found a similar sized dead zone during its annual five-week summer fish survey.


'/>"/>

Contact: Ben Sherman
ben.sherman@noaa.gov
301-713-3066
NOAA Headquarters
Source:Eurekalert

Related biology news :

1. Social parasites of the smaller kind
2. 2007 ozone hole smaller than usual
3. Iowa State researchers look for smaller, cheaper, 1-dose vaccines
4. Penn engineers create carbon nanopipettes that are smaller than cells and measure electric current
5. Nanoparticles in the home: More and smaller than previously detected
6. New research shows dinosaurs may have been smaller than we thought
7. Smaller plants punch above their weight in the forest, say Queens biologists
8. Invasive Australian jellyfish sighted in Gulf of Mexico in summer 2007
9. Small-scale fishing in Mexico rivals industrial fisheries in accidental turtle deaths
10. Gulf of Mexico dead zone to be studied by University of Texas at Austin marine scientists
11. UTSA and University in Mexico to collaborate in science research
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:5/24/2016)... -- Ampronix facilitates superior patient care by providing unparalleled technology to leaders of the ... latest premium product recently added to the range of products distributed by Ampronix. ... ... ... Display- Ampronix News ...
(Date:5/16/2016)... NEW YORK , May 16, 2016   ... authentication solutions, today announced the opening of an IoT ... to strengthen and expand the development of embedded ... provides an unprecedented level of convenience and security with ... to authenticate one,s identity aside from DNA. EyeLock,s platform ...
(Date:5/9/2016)... -- Elevay is currently known as the ... high net worth professionals seeking travel for work   ... there is still no substitute for a face-to-face meeting. ... deal with a firm handshake. This is why wealthy ... citizenship via investment programs like those offered by the ...
Breaking Biology News(10 mins):
(Date:6/23/2016)... 2016 Andrew D ... http://doi.org/10.17925/OHR.2016.12.01.22 Published recently in ... from touchONCOLOGY, Andrew D Zelenetz , discusses ... care is placing an increasing burden on healthcare ... therapies. With the patents on many biologics expiring, ...
(Date:6/23/2016)... Francisco, CA (PRWEB) , ... June 23, 2016 ... ... (EDC) software, is exhibiting at the Pennsylvania Convention Center and will showcase its ... Annual conference. ClinCapture will also be presenting a scientific poster on Disrupting Clinical ...
(Date:6/23/2016)... ... June 23, 2016 , ... Velocity Products, a division of ... and optimized exclusively for Okuma CNC machining centers at The International Manufacturing Technology ... among several companies with expertise in toolholding, cutting tools, machining dynamics and distribution, ...
(Date:6/23/2016)... 23, 2016 ReportsnReports.com adds ... to its pharmaceuticals section with historic and forecast ... much more. Complete report on the ... profiling 15 companies and supported with 261 tables ... . The Global Cell Culture ...
Breaking Biology Technology: