Scientists at the University of California, San Diego, conducted a study that showed how ocean warming will affect its structure over the next 100 years. They found that young water in the ocean will age, while old water, conversely, will become younger.
This phenomenon is linked to the loss of dissolved oxygen in the water, which occurs due to its consumption by marine organisms and bacteria, as well as through chemical reactions. If the water does not rise to the surface, it cannot replenish this oxygen deficit, which leads to its “aging.”
The study also indicates that warmer water dissolves less oxygen, which could have serious consequences for underwater ecosystems. However, exactly how these changes manifest in different regions remained unclear until now.
According to the new data, older waters in the Pacific Ocean’s thermocline—located at a depth of approximately 200–1,000 meters—will become “younger,” while younger waters will “age.” This phenomenon is caused by a weakening of circulation between water layers due to rising temperatures.
Scientists note that different parts of the Pacific Ocean respond differently to these changes. For example, in the subtropical part of the northern Pacific Ocean, the thermocline is influenced by younger water mixing in from above, while in the tropical part, it is influenced by older water rising from below.
These research findings can be explained by the “remote influence” of the Southern Ocean, where warming is also occurring. Scientists emphasize that the slowing of vertical water currents is the result of the combined influence of thermal factors in both the Pacific and Southern Oceans.
