Deep plumes of oil could cause dead zones in the Gulf

August 19, 2010

WASHINGTON-- A new simulation of oil and methane leaked into the Gulf of Mexico suggests that deep hypoxic zones or "dead zones" could form near the source of the pollution. The research investigates five scenarios of oil and methane plumes at different depths and incorporates an estimated rate of flow from the Deepwater Horizon spill, which released oil and methane gas into the Gulf from April to mid July of this year.

A scientific paper on the research has been accepted for publication by Geophysical Research Letters, a journal of the American Geophysical Union,

Scientists at the National Oceanic and Atmospheric Administration (NOAA) and Princeton University conducted the research. Based on their simulations, they conclude that the ocean hypoxia or toxic concentrations of dissolved oil arising from the Deepwater Horizon blowout are likely to be "locally significant but regionally confined to the northern Gulf of Mexico."

A hypoxic or "dead" zone is a region of ocean where oxygen levels have dropped too low to support most forms of life, typically because microbes consuming a glut of nutrients in the water use up the local oxygen as they consume the material.

"According to our simulations, these hypoxic areas will be peaking in October," says study coauthor Robert Hallberg of the NOAA Geophysical Fluid Dynamics Laboratory in Princeton, N.J.. "Oxygen drawdown will go away slowly, as the tainted water is mixed with Gulf waters that weren't affected. We're estimating a couple of years" before the dead zone has dissipated, he adds.

Although the Princeton-NOAA study was carried out when the flow rate from the Deepwater Horizon spill was still underestimated, the simulated leak lasted longer than did the actual spill. Consequently, says Alistair Adcroft of Princeton University and the NOAA Geophysical Fluid Dynamics Laboratory, another study coauthor, "the overall impact on oxygen turns out to be about the same" as would be expected from the Deepwater Horizon spill.
-end-
Notes for Journalists

As of the date of this press release, the paper by Adcroft et al. is still "in press" (i.e. not yet published). Journalists and public information officers (PIOs) of educational and scientific institutions who have registered with AGU can download a PDF copy of this paper in press by clicking on this link: http://www.agu.org/journals/pip/gl/2010GL044689-pip.pdf

Or, you may order a copy of the paper by emailing your request to Maria-José Viñas at mjvinas@agu.org or to Kitta MacPherson at kittamac@princeton.edu. Please provide your name, the name of your publication, and your phone number.

Neither the paper nor this press release are under embargo.

Title: "Simulations of underwater plumes of dissolved oil in the Gulf of Mexico"

Contact information for the authors: Robert Hallberg, NOAA Geophysical Fluid Dynamics Laboratory, Tel. +1 (609) 452- 6508, Email Robert.Hallberg@noaa.gov

Alistair Adcroft, Princeton University and NOAA Geophysical Dynamic laboratory, Tel. +1 (609) 987-5073, Email aadcroft@princeton.edu

American Geophysical Union

Related Dead Zone Articles from Brightsurf:

New fault zone measurements could help us to understand subduction earthquake
University of Tsukuba researchers have conducted detailed structural analyses of a fault zone in central Japan to identify the specific conditions that lead to devastating earthquake.

Is the Earth's transition zone deforming like the upper mantle?
In a recently published paper in Earth and Planetary Science Letters, researchers from the Geodynamics Research Center, Ehime University and the University of Lille combine numerical modeling of dislocation glide and results from diffusion experiments to revisit the rheology of wadsleyite, ringwoodite and majorite garnet under geological strain rates across the transition zone of the Earth's mantle based on theoretical plasticity modeling.

Behind the dead-water phenomenon
What makes ships mysteriously slow down or even stop as they travel, even though their engines are working properly?

Badger behavior inside the cull zone
A study led by researchers at international conservation charity ZSL (Zoological Society of London) and Imperial College London has found that culling drives badgers to roam 61% further afield -- helping to explain why the practice, intended to reduce bovine TB transmission, can sometimes exacerbate the problem instead

A Goldilocks zone for planet size
Harvard University researchers described a new, lower size limit for planets to maintain surface liquid water for long periods of time, extending the so-called Habitable or 'Goldilocks'' Zone for small, low-gravity planets.

Large summer 'dead zone' forecast for Chesapeake Bay after wet winter and spring
Ecologists from the University of Maryland Center for Environmental Science and the University of Michigan are forecasting a large Chesapeake Bay 'dead zone' in 2019 due to well-above-average river flows associated with increased rainfall in the watershed since last fall.

2019 'dead zone' may be the second largest on record
A recent forecast of the size of the 'Dead Zone' in the northern Gulf of Mexico for late July 2019 is that it will cover 8,717-square-miles of the bottom of the continental shelf off Louisiana and Texas.

How to interact between mantle and crustal components in the subduction zone?
Subduction process drives the differential evolution of the earth and realizes material cycle and energy exchange.

The bird that came back from the dead
New research has shown that the last surviving flightless species of bird, a type of rail, in the Indian Ocean had previously gone extinct but rose from the dead thanks to a rare process called 'iterative evolution'.

Devil rays may have unknown birthing zone
The discovery of dozens of pregnant giant devil rays tangled in fishing nets in a village along Mexico's Gulf of California could mean the endangered species has a previously unknown birthing zone in nearby waters, a Duke University study suggests.

Read More: Dead Zone News and Dead Zone Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.