Oceans running out of oxygen as temperatures rise
Climate change and nutrient pollution are driving the oxygen from our oceans, and threatening many species of fish. That’s the conclusion of the biggest study of its kind, undertaken by conservation group IUCN.
While nutrient run-off has been known for decades, researchers say that climate change is making the lack of oxygen worse. Around 700 ocean sites are now suffering from low oxygen, compared with 45 in the 1960s. Researchers say the depletion is threatening species including tuna, marlin and sharks.
As more carbon dioxide is released enhancing the greenhouse effect, much of the heat is absorbed by the oceans. In turn, this warmer water can hold less oxygen.