Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

U-M forecasters predict second-smallest Gulf of Mexico 'dead zone'

22.06.2012
A dry spring in portions of the Midwest is expected to result in the second-smallest Gulf of Mexico "dead zone" on record in 2012, according to a University of Michigan forecast released today.
The U-M prediction calls for a 2012 Gulf of Mexico dead zone of about 1,200 square miles, an area the size of Rhode Island. If the forecast is correct, 2012 would replace 2000 (1,696 square miles) as the year with the second-smallest Gulf dead zone. The smallest Gulf oxygen-starved, or hypoxic, zone was recorded in 1988 (15 square miles).

"While it's encouraging to see that this year's Gulf forecast calls for a significant drop in the extent of the dead zone, we must keep in mind that the anticipated reduction is due mainly to decreased precipitation in the upper Midwest and a subsequent reduced water flow into the Gulf," said aquatic ecologist Donald Scavia, professor at the U-M School of Natural Resources and Environment. "The predicted 2012 dead-zone decline does not result from cutbacks in nitrogen use, which remains one of the key drivers of hypoxia in the Gulf."

The U-M prediction is one of two Gulf dead zone forecasts released today by the National Oceanic and Atmospheric Administration, which funds the research. The other NOAA-supported team, from the Louisiana Universities Marine Consortium and Louisiana State University, predicts a 2012 Gulf dead zone of 6,213 square miles.

“These dead zones are ecological time bombs.”
—U-M aquatic ecologist Donald Scavia

The Michigan forecast model is based solely on 2012 spring nutrient inputs from the Mississippi River, which are significantly lower than average due to drought conditions throughout much of the watershed. The Louisiana State University forecast model takes into account last year's above-normal nutrient load, which the Louisiana researchers say can remain in bottom sediments and can result in a "carryover effect" that increases the size of the 2012 dead zone.

Last year, the Gulf dead zone measured 6,765 square miles. The largest Gulf hypoxic zone measured to date occurred in 2002 and encompassed more than 8,400 square miles. The Gulf dead zone has averaged about 6,000 square miles over the past five years.

This year, for the first time, Scavia's U-M team was able to forecast the volume of hypoxic water contained in the dead zone. The most likely 2012 scenario corresponds to a volume of 2.6 cubic miles, according to the U-M team.

Scavia, director of the Graham Sustainability Institute and special counsel to the U-M president for sustainability, also released his annual Chesapeake Bay dead zone forecast today. It calls for an average-size dead zone in the Bay this year, down significantly from last summer's record-setter.

"These dead zones are ecological time bombs," he said. "Without determined local, regional and national efforts to control nutrient loads, we are putting major fisheries at risk."

In 2009, the dockside value of commercial fisheries in the Gulf of Mexico was $629 million. Nearly 3 million recreational anglers further contributed more than $1 billion to the Gulf economy, taking 22 million fishing trips.

“We should not lose sight of the ongoing need to reduce the flow of nutrients to the Mississippi River and thus the Gulf.”
—NOAA Administrator Jane Lubchenco

Farmland runoff containing fertilizers and livestock waste—some of it from as far away as the Corn Belt—is the main source of the nitrogen and phosphorus that cause the annual Gulf of Mexico hypoxic zone. Each year in late spring and summer, these nutrients flow down the Mississippi River and into the Gulf, fueling explosive algae blooms there.

When the algae die and sink, bottom-dwelling bacteria decompose the organic matter, consuming oxygen in the process. The result is an oxygen-starved region in bottom and near-bottom waters: the dead zone.

"This forecast is a good example of NOAA, USGS and university partnerships delivering ecological forecasts that quantify the linkages between the watershed and the coast," said NOAA Administrator Jane Lubchenco. "While the occurrence of a low-flow year following a year with major flooding will help us to evaluate any carryover effect from prior years, we should not lose sight of the ongoing need to reduce the flow of nutrients to the Mississippi River and thus the Gulf."

According to U.S. Geological Survey estimates, the Mississippi and Atchafalaya rivers transported 58,100 metric tons of nitrogen (in the form of nitrite plus nitrate) to the northern Gulf in May 2012, an amount that is 56 percent lower than average May nitrogen loads estimated in the last 33 years.

"These forecasts are the product of decades of research, monitoring and modeling on how decisions we make in the vast drainage basin of the Mississippi and its tributaries translates into the health of the coastal zone of the Gulf of Mexico," said U.S. Geological Survey Director Marcia McNutt. "Comparing the actual hypoxic zone against the predictions will help scientists better understand the multiyear memory of this complex land-sea system, and ultimately better inform options for improving ecosystem productivity."

About a thousand miles northeast of the Gulf of Mexico in Chesapeake Bay, this year's hypoxic zone is expected to measure about 1.5 cubic miles, Scavia said. That's about average compared to measured volumes since 2000 but much smaller than last year's record-setter of 2.75 cubic miles, which was due to spring storms that washed large amounts of nutrients into rivers that feed the Bay.

So far in 2012, rainfall in the Chesapeake Bay watershed has been 50-to-75 percent of normal, Scavia said.

The actual size of the 2012 Gulf hypoxic zone will be announced following a NOAA-supported monitoring survey led by the Louisiana Universities Marine Consortium between July 27 and Aug. 3.

The amount of nitrogen entering the Gulf of Mexico each spring has increased about 300 percent since the 1960s, mainly due to increased agricultural runoff. The Gulf of Mexico/Mississippi River Watershed Nutrient Task Force has targeted 1,900 square miles as a long-term goal for the size of the Gulf dead zone.

Related Links:
University of Michigan hypoxia forecasts:
http://snre.umich.edu/scavia/hypoxia-forecasts
NOAA hypoxia pages:
www.cop.noaa.gov/gulf_hypoxia_forecast/default.aspx
Louisiana Universities Marine Consortium hypoxia information and forecasts: www.gulfhypoxia.net
U.S. Geological Survey Gulf of Mexico nutrient and stream flow information: http://toxics.usgs.gov/hypoxia/mississippi/oct_jun/index.html


U-M Sustainability fosters a more sustainable world through collaborations across campus and beyond aimed at educating students, generating new knowledge, and minimizing our environmental footprint. Learn more at sustainability.umich.edu

Jim Erickson | EurekAlert!
Further information:
http://www.umich.edu

More articles from Ecology, The Environment and Conservation:

nachricht Innovative grilling technique improves air quality
01.07.2020 | Fraunhofer Institute for Building Physics IBP

nachricht Traffic density, wind and air stratification influence the load of the air pollutant nitrogen dioxide
26.06.2020 | Leibniz-Institut für Troposphärenforschung e. V.

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: ILA Goes Digital – Automation & Production Technology for Adaptable Aircraft Production

Live event – July 1, 2020 - 11:00 to 11:45 (CET)
"Automation in Aerospace Industry @ Fraunhofer IFAM"

The Fraunhofer Institute for Manufacturing Technology and Advanced Materials IFAM l Stade is presenting its forward-looking R&D portfolio for the first time at...

Im Focus: AI monitoring of laser welding processes - X-ray vision and eavesdropping ensure quality

With an X-ray experiment at the European Synchrotron ESRF in Grenoble (France), Empa researchers were able to demonstrate how well their real-time acoustic monitoring of laser weld seams works. With almost 90 percent reliability, they detected the formation of unwanted pores that impair the quality of weld seams. Thanks to a special evaluation method based on artificial intelligence (AI), the detection process is completed in just 70 milliseconds.

Laser welding is a process suitable for joining metals and thermoplastics. It has become particularly well established in highly automated production, for...

Im Focus: A structural light switch for magnetism

A research team from the Max Planck Institute for the Structure of Dynamics (MPSD) and the University of Oxford has managed to drive a prototypical antiferromagnet into a new magnetic state using terahertz frequency light. Their groundbreaking method produced an effect orders of magnitude larger than previously achieved, and on ultrafast time scales. The team’s work has just been published in Nature Physics.

Magnetic materials have been a mainstay in computing technology due to their ability to permanently store information in their magnetic state. Current...

Im Focus: Virtually Captured

Biomechanical analyses and computer simulations reveal the Venus flytrap snapping mechanisms

The Venus flytrap (Dionaea muscipula) takes only 100 milliseconds to trap its prey. Once their leaves, which have been transformed into snap traps, have...

Im Focus: NASA observes large Saharan dust plume over Atlantic ocean

NASA-NOAA's Suomi NPP satellite observed a huge Saharan dust plume streaming over the North Atlantic Ocean, beginning on June 13. Satellite data showed the dust had spread over 2,000 miles.

At NASA's Goddard Space Flight Center in Greenbelt, Maryland, Colin Seftor, an atmospheric scientist, created an animation of the dust and aerosols from the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Dresden Nexus Conference 2020: Same Time, Virtual Format, Registration Opened

19.05.2020 | Event News

Aachen Machine Tool Colloquium AWK'21 will take place on June 10 and 11, 2021

07.04.2020 | Event News

International Coral Reef Symposium in Bremen Postponed by a Year

06.04.2020 | Event News

 
Latest News

First exposed planetary core discovered

01.07.2020 | Physics and Astronomy

Energy-saving servers: Data storage 2.0

01.07.2020 | Power and Electrical Engineering

Laser takes pictures of electrons in crystals

01.07.2020 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>