JUL 23

NASA has created new maps showing the grim reality of marine dead zones.  These areas of deep water where oxygen levels are too low for marine life to survive have grown at a staggering pace since the middle of the 20th century.

The dead zones are created when fertilizer run off from crops makes it into the ocean, creating massive algae blooms.  When the algae dies, it sinks to the bottom where microbes decompose the matter, which consumes oxygen and creates a suffocating environment for marine life.

NASA was able to located the areas where this was occurring by using satellites that detect high concentrations of particulate organic matter.  Those high concentrations are a signal of extra fertile areas that lead to dead zones.

The dead zones are mainly located along the coasts of large population centers, with the east coast of the U.S. and the coasts of Northern Europe having the largest numbers of these zones.

Since the 1960's, the creation of dead zones has snowballed, with the total amount of area occupied by dead zones now equaling 152,000 square miles and 400 different ecosystems being affected.

via Yale e360

Comments (4)

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Marine Dead Zones
written by Heather, July 25, 2010

There is a lot more to this story. You mention that microbes feed on dead algae, which creates an anoxic environment, but there are microbes that also decompose oil with the same effect. This would help explain the large dead zone in the gulf of Mexico. I am curious now to know how recently this map was published and the reasons as to why it was made.

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We have total disregard
written by Warren Pollock, July 25, 2010

We have total disregard for the human cost of our irresponsibility and kowtowing to a perversion of capitalism; law based and financial based capitalism.

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@Warren
written by Mike, July 27, 2010

Don't worry! If enough people purchase green consumer goods and kinetic energy powered flashlights, solar panels and hybrid vehicles etc we will enter into the marvellous new age of green pollution where everything is exactly as it was before (but is GREEN).

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...
written by Fredrik, August 13, 2010

The baltic sea (north europe) is really a sad example of how years of agricultural revolution and untreated sewage water... The former Sovjet states of East Europe didn't have money to spend on sewage treatments, and are still struggling to get up and running.

Ecotoxicological surveys on fish, and of fish eggs show high amounts of tumours and high EROD activity... Which isn't good at all. One also find lots of misshaped fish... And the microbiological activity with the eutrophication makes sure that dead sea bottoms remain dead.

However, hard work and patience have made several bays in Scandinavia re oxygenated, and the lobster and fish populations have started to recover...

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