23 Jul 2010:
Map Illustrates Extent
of the Planet’s Marine Dead Zones
A new NASA map illustrates the significant expansion of the world’s marine dead zones
regions where dissolved oxygen is so low marine species cannot survive. Many of these dead zones occur off densely populated coastlines, particularly along the eastern United States and in Northern Europe. Scientists produced the map using data from satellites that can detect high concentrations of particulate matter, an indicator of overly fertile waters that can create dead zones. The zones arise when fertilizers applied to crops wash into streams and rivers, eventually reaching coastal waters, where the excess nutrients trigger massive algae blooms. When the algae die, they sink to the ocean’s depths, where they essentially become fertilizer for microbes that decompose the organic matter and consume oxygen, suffocating marine life. In 2008, a study found that dead zones had spread exponentially
since the 1960s, affecting more than 400 ecosystems and a total area of more than 152,000 square miles (245,000 square kilometers).
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A look at how acidifying oceans could threaten the Dungeness crab, one of the most valuable fisheries on the U.S. West Coast. 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.
An indigenous tribe’s deadly fight to save its ancestral land in the Amazon rainforest from logging. 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.
Residents of the Chocó Rainforest in Ecuador are choosing to plant cacao over logging in an effort to slow deforestation.
Watch the video.
Tribal people and ranchers join together to stop a project that would haul coal across their Montana land. Watch the video.