Scientists are issuing serious warnings about the exponential growth of ocean ‘dead zones’, known as areas of water with low to no oxygen, which are caused by human pollutants.
According to the NOAA (National Oceanic and Atmospheric Administration), they “deplete the oxygen required to support most marine life in bottom and near-bottom water”.
Such zones with absolutely no oxygen have quadrupled since 1950, and dead-zones with low oxygen, content near to the coast have multiplied almost tenfold.
However, almost all aquatic life cannot survive in such dead zones.
If this rate of de-oxygenation continues, scientists predict that the resulting mass-extinctions could be catastrophic for the millions of people that rely on such ecosystems for nutrition, and those who otherwise rely on the sea for their livelihood.
The oceans provide a primary food source for over 500 million people, and jobs for 350 million more.
Undoubtedly, global warming is a major factor in the catastrophic growth of these oxygen-starved areas.
Warmer waters hold less oxygen, so the climate change caused by the burning of fossil fuels creates bodies of water much less suitable to life.
Although dead zones can occur naturally, they primarily appear near areas where heavy industrial and agricultural activity spill nutrients and pollutants into the water.
The campaign group Mighty Earth recently exposed such an example in the Gulf of Mexico, where an extremely large dead zone (8,500 square miles) has been linked to a local large-scale meat producer.
Lucia von Reusner, the Campaign Manager said: “These dead zones will continue to expand unless the major meat companies start cleaning up their supply chains to keep pollution out of our waters.”
Luckily, ocean dead-zones are reversible. If their causes are eliminated, waters may return to their natural oxygen level.