Earth’s past warm periods witnessed the shrinkage of the open ocean’s oxygen-deficient zones.
According to a new study from an international team led by researchers from the Max Planck Institute for Chemistry, the oxygen-deficient zones that occur in the open ocean shrank in long warm periods of the past.
When oxygen becomes scarce, life has a hard time. This is just as true for mountain regions above 7000 meters but also for bodies of water. For example, in tropical ocean regions off of West America and West Africa and in the northern Indian Ocean, only specialized microbes and organisms with a slow metabolism such as jellyfish can survive.
In the last 50 years, oxygen-deficient zones in the open ocean have increased. ...