Gulf dead zone big as New Jersey in 2007
Mississippi River plume meets Gulf of Mexico at Southwest Pass.
In 2007, the “dead zone” in the Gulf of Mexico isn’t as large as predicted, but it’s still the third-largest dead zone ever mapped in the Gulf.
It’s an area about as big as the state of New Jersey, off the coast of Texas and Louisiana. That’s according to Nancy Rabalais, who led a team of scientists aboard a research vessel that mapped the extent of this year’s dead zone.
Rabalais – who is executive director of Louisiana Universities Marine Consortium – said what makes this water “dead” is a lack of oxygen. She said the lack of oxygen in Gulf of Mexico waters affects animals on the sea floor.
Nancy Rabalais: Usually, the fish are better swimmers. They can move out of the area faster. We’ve seen brown shrimp come up to the surface of the water. We’ve seen eels that live in the sediments come up to the surface of the water. And this is a trip of about 65 feet for these organisms to go from the bottom of the sediments all the way to the top. Not all of them are intended to be swimming organisms. They’re obviously stressed.
Rabalais said the size of the Gulf dead zone depends mainly on how much nitrogen runoff is carried by the Mississippi River to the Gulf. Nitrogen feeds algae, which eventually decomposes and depletes bottom waters of oxygen.
Our thanks to NOAA, the National Oceanographic and Atmospheric Administration.
Science News Headlines, brought to you by Earth & Sky
Get all your science news in one place.
Rabalais said that, in 2007, stronger than average storms stirred up waters and reduced the spread of the “dead zone.” So it wasn’t as large as predicted. But it was still the third-largest ever mapped.
She added, “While we’re out there, we have anything from dirty brown water, through green water – usually where the plankton is growing – to crystal clear blue water far away from the river plumes. You can’t see the low oxygen from the surface. But you can see the effects of these large phytoplankton plumes. As they decay they sink to the bottom and make stringy particles in the upper water column. You can see that.”
The condition of low oxygen, contributing to ocean dead zones, is called hypoxia.
Gulf ‘dead zone’ still 3rd largest
Our thanks to:
Nancy Rabalais
Executive Director
Louisiana Universities Marine Consortium
When was the dead zone reported the largest? I wonder what the changes look like for the last 5 years or so and if there’s a pattern.
I think it’s just getting larger and larger. Does is happen cuz on nitrogen runoff?
Besides the dead zone in the Gulf of Mexico, there are about 150 similar dead (hypoxic) zones in other areas of our water world. And, most of them are growing in size and duration. In my opinion – this is a far greater and more immediate threat to our survival than the global warming issue. Even the smallest effort to conserve or not pollute water will bring an immediate positive response from our water world, and help water to restore and bring forth life in abundance. Blessings, William E. Marks ( http://www.watervoices.com )
Does global warming have any effect on these hypoxic zones?
Don’t worry- if the dead zones don’t kill off most sea life, the Japanese and Chinese fishing vessels will.
Hypoxic, or “dead zones”, are created mostly by the chemical runoff from agriculture (ferilizers, pesticides, herbicides, fungicides) and other areas of intense chemical deposition (i.e.: golf courses; slaughter houses; cattle and hog feedlots, etc.), storm water runoff, and certain industries. Such chemical loads create these so-called “dead zones” by completly depleting the oxygen in the water from the surface to the bottom. These dead zones are the direct result of human mismanagement of chemicals and land usage. Global warming has little to do with these dead zones – however, the heating up of our oceans may further exacerbate the problem in the future. Yes, the overfishing of our oceans by the Japanese, Chinese, and other countries with short-sighted and greedy commercial interets, represents a threat to maintaining renewable and sustaninable sources of protein in our oceans. For more guidance and information of this subject I recommend you visit www.oceana.org – they are doing wonderful work in trying to preserve our ocean fisheries. Respectfully, William E. Marks (Water Voices from Around The World)
life is multi color death is one color. death color is teach you.
huminty lovesave your color,live for ohter.becouse .other is you.