A new study conducted by an international team of physical oceanographers managed to demonstrate what many have warned before, that warmer oceans lead to less oxygen, resulting in a limitation of the regions where fishes and other marine organisms are able to live.

Led by Lothar Stramma from the Leibniz Institute of Marine Sciences in Kiel, Germany, and co- authored by Janet Sprintall, a physical oceanographer at Scripps Oceanography, the study analyzed a database of ocean measurement and concluded that the level of oxygen declined during the last 50 years.

“We found the largest reduction in a depth of 300 to 700 meters (985 to 2,300 feet) in the tropical northeast Atlantic, whereas the changes in the eastern Indian Ocean were much less pronounced,” said Stramma. “Whether or not these observed changes in oxygen can be attributed to global warming alone is still unresolved. The reduction in oxygen may also be caused by natural processes on shorter time scales.”

While usually this type of studies do not essentially change any of the world’s actions regarding the global warming, it is likely that this particular one would be heard and would raise some questions, since the ecological impacts of the lower levels of oxygen could have serious biological and most of all, economical consequences.

“Thicker oxygen minimum zones could affect nutrient cycling, predator-prey relationships and plankton migrations. Where the expanding oxygen-minimum zones impinge on continental margins, we could see huge ecosystem changes,” Lisa Levin, a biological oceanographer at Scripps Oceanography, said.