Scripps Institute study warns of worldwide oxygen loss in oceans and freshwater

Researchers led by the Scripps Institution of Oceanography at the University of California, San Diego have issued a warning that dissolved oxygen is rapidly decreasing in oceans, coastal waters, rivers and lakes around the globe. The findings, published in *Limnology and Oceanography*, describe the phenomenon as “deoxygenation” and argue it should be recognised as a new planetary boundary alongside climate change, ocean acidification and biodiversity loss.

The study identifies three main drivers: rising global temperatures, excess nutrient pollution and altered deep‑water ventilation. Scientists say the loss of oxygen could persist for centuries and be irreversible on a human‑life timescale, threatening aquatic ecosystems that underpin climate regulation. Lead author Dr. Erica Ferrer emphasized, “The health and stability of our planet depend on the health and stability of aquatic ecosystems, which need oxygen to function normally.”