24 Aug 2012:
Drought Conditions Trigger
Smallest Gulf ‘Dead Zone’ in Years
U.S. scientists say the nation’s worst drought in five decades has had at least one positive effect: the smallest so-called “dead zone” seen in the Gulf of Mexico in years
. In a 1,200-mile research cruise
Algal blooms in the Gulf of Mexico
conducted in the waters of the gulf this month, scientists from Texas A&M University found only 1,580 square miles of oxygen-depleted, or hypoxic, water in the gulf, compared with 3,400 square miles last August. The hypoxic zone is created when algal blooms, caused by large amounts of fertilizer and nutrients washing into the gulf, remove oxygen from the water and suffocate marine life. According to the researchers, hypoxia was found only in the waters near the Mississippi River delta — which accounts for nearly 90 percent of all freshwater runoff in the gulf — and no hypoxia was observed off the Texas coast. “What has happened is that the drought has caused very little fresh-water runoff and nutrient load into the gulf, and that means a smaller region for marine life to be impacted,” said Steve DiMarco, an oceanography professor at Texas A&M. According to DiMarco, nitrogen levels in the Gulf caused by human activities, including fertilizer use
, have tripled over the last 50 years, triggering dead zones that have been as large as 9,400 square miles.
Yale Environment 360 is
a publication of the
Yale School of Forestry
& Environmental Studies
Yale Environment 360
articles are now available in Spanish and Portuguese on Universia
, the online educational network. Visit the site.
Business & Innovation
Policy & Politics
Pollution & Health
Science & Technology
Antarctica and the Arctic
Central & South America
Tribal people and ranchers join together to stop a project that would haul coal across their Montana land. Watch the video.
is now available for mobile devices at e360.yale.edu/mobile
An aerial view of why Europe’s per capita carbon emissions are less than 50 percent of those in the U.S. View the photos.
Ugandan scientists monitor the impact of climate change on one of Africa’s most diverse forests and its extraordinary wildlife. Learn more.
video series looks at the staggering amount of food wasted in the U.S. – a problem with major human and environmental costs. Watch the video.
video goes onto the front lines with Colorado firefighters confronting deadly blazes fueled by a hotter, drier climate. Watch the video.
A three-part series Tainted Harvest
looks at the soil pollution crisis in China, the threat it poses to the food supply, and the complexity of any cleanup. Read the series.