Advertisement

If you have an ACS member number, please enter it here so we can link this account to your membership. (optional)

ACS values your privacy. By submitting your information, you are gaining access to C&EN and subscribing to our weekly newsletter. We use the information you provide to make your reading experience better, and we will never sell your data to third party members.

ENJOY UNLIMITED ACCES TO C&EN

Environment

Dead Zone Smaller, But More Severe

by Britt E. Erickson
August 3, 2009 | A version of this story appeared in Volume 87, Issue 31

[+]Enlarge
Credit: NOAA
Dead zone in Gulf of Mexico is smaller than expected this year.
Credit: NOAA
Dead zone in Gulf of Mexico is smaller than expected this year.

The Gulf of Mexico's "dead zone," an area where oxygen levels are too low to support most forms of life, is smaller than expected but more severe this year, report scientists at Louisiana Universities Marine Consortium. Typically the dead zone area is limited to bottom waters just above the seafloor, but the current dead zone extends closer to the water surface than usual. Researchers predicted this year's dead zone would be comparable with last year's, with an area of about 8,000 sq miles, but unusual weather patterns reoxygenated the waters, resulting in this year's dead zone measuring only 3,000 sq miles. "These results at first glance are hopeful, but the smaller than expected area of hypoxia appears to be related to short-term weather patterns ... not a reduction in the underlying cause, excessive nutrient runoff," Robert Magnien, director of NOAA's Center for Sponsored Coastal Ocean Research, said in a statement. Each year, the dead zone forms in the Gulf of Mexico when excess nitrogen and phosphorus from agricultural runoff stimulate phytoplankton growth, causing low levels of dissolved oxygen.

Article:

This article has been sent to the following recipient:

0 /1 FREE ARTICLES LEFT THIS MONTH Remaining
Chemistry matters. Join us to get the news you need.