Scientists have warned that 80% of the world's rivers are rapidly losing oxygen
Dissolved oxygen levels have dropped significantly in nearly 80% of the world’s rivers over the past few decades, threatening mass die-offs of aquatic organisms and widespread destruction of aquatic ecosystems. Tropical rivers, including the Amazon and the Ganges, have been hit hardest by this environmental trend.
This is reported by Science Alert. Researchers from the Chinese Academy of Sciences analyzed detailed climate and satellite data from 1985 to 2023 for over 16,000 rivers worldwide and found that dissolved oxygen levels in the water are steadily decreasing by an average of 0.045 milligrams per liter every decade.
Scientists cite global warming as the main cause of deoxygenation, since rising temperatures cause water to hold gases much less effectively and literally push oxygen out. According to the analysis, climate change accounts for about 63% of the total decline in oxygen levels, with additional negative factors including dam construction, extreme heat, and human activity. Human impact leads to reduced river flows and increased concentrations of salts, nutrients, and organic waste, which significantly accelerates the degradation of water bodies.
If global carbon dioxide emissions are not reduced, by the end of this century, rivers in most regions of South America, the Arctic, India, and the eastern United States will lose another 10% of their oxygen. Researchers emphasize that this will lead to a much more frequent formation of dead zones worldwide—areas where fish, plants, or plankton cannot survive due to a lack of oxygen. Lead researcher Qi Guan explained in a comment to the Associated Press that this process is very slow, but its prolonged course will inevitably lead to a catastrophic loss of biodiversity and a critical deterioration in freshwater quality.
As a reminder, the Swiss Glacier Gris has confirmed the threat of global warming.
The UN has also recognized the right of refugees to seek asylum due to global warming.
