Climate crisis: rivers are heating up very quickly and losing oxygen

A new study warns that rivers are warming up and, as a result, losing oxygen. Activity recorded in river systems caused by the effects of climate change is occurring at a faster rate than that recorded in the oceans. The study, published this Thursday in the journal Nature Climate Changewarns that the situation is so critical that it may lead to “acute death” some species in the same century.

The team looked at a sample of 796 rivers in the United States and Central Europe. He Warming was found in 87% of these water sources, and oxygen loss was found in 70%. of all the rivers considered.

“This is a wake-up call,” said Li Li, a member of the Pennsylvania State University Department of Civil and Environmental Engineering and a member of the research team. “We know that climate change has caused warming and loss of oxygen in the oceans, but we did not expect this to happen in shallow, flowing rivers,” he said in a statement.

This the first study to comprehensively analyze temperature change and deoxygenation rate in rivers. Residents in urban areas are facing faster warming, the analysis warns. In agricultural rivers, the temperature rise occurs more slowly, but with a faster decrease in oxygen. “What we found has serious implications for water quality and the health of aquatic ecosystems around the world,” Li said.

Warming rivers are dangerous for animals and humans

Research group used artificial intelligence to restore historical data, which are usually small, on the quality of water in rivers. The researchers trained the computer model on a wide range of indicators, from annual rainfall to soil type and sunlight. Calculations from 1981 to 2019 were taken into account.

The sample included 580 rivers in the United States and 216 rivers in Central Europe. On average, rivers in the US are warming by 0.16°C every decade, and in Europe by about 0.27°C. The rate of deoxygenation reached 1% to 1.5% loss every decade.

Some coastal areas, such as the Gulf of Mexico, often experience dead zones in the summer. “This study shows us that the same thing can happen in rivers,” Li said.

The health of rivers affects everything in and around them. From aquatic life to people for whom rivers are a source of water and food. In addition, the decrease in oxygen content in rivers It also results in greenhouse gas emissions and toxic metal emissions.

The team’s forecast model warns that future rates of deoxygenation in rivers could be 1.6 to 2.5 times higher than those observed historically. If so, then, as the study says, Some fish species could disappear completely within the next 70 years. threatening aquatic diversity as a whole.

NASA has confirmed that last summer in the northern hemisphere was the hottest on record. July was the month with the highest temperatures since records began, followed by August. This year, 2023 will be the second warmest year after 2016.