It has long been known that cold water absorbs gases from the atmosphere better. For example, oceans slow global warming by capturing and storing large amounts of carbon dioxide. However, with the same heating, they warm up and their ability to absorb begins to decrease, leaving more CO2 in the atmosphere.₂. The same applies to oxygen.

What is known

To carry out the analysis, scientists from the University of Pennsylvania, US, trained a computer model on a wide range of data, from annual precipitation to soil type and sunlight. Nearly 800 rivers were studied – 580 in the United States and 216 in Europe. The model showed that 87% of rivers have warmed and 70% have lost oxygen in the last four decades.

Interestingly, urban rivers warmed the fastest, while agricultural rivers experienced the slowest warming, but were still prone to oxygen loss. Scientists also used this model to predict future rates of development of the problem and found that the rate of deoxygenation in all rivers studied was 1.6-2.5 times higher than before.

Decreasing oxygen levels in rivers leads to increased greenhouse gas emissions and the release of toxic metals. The model predicted that over the next 70 years: Some fish species may disappear completely from rivers because there will be nothing left for them to breathe..

This is a wake-up call. We knew that global warming was causing warming and loss of oxygen in the oceans, but we did not expect this to happen in rivers. This is the first study to examine temperature change and deoxygenation.
– say scientists.

Rivers are essential to the survival of many species, including our own. So understanding how they change can help slow down or stop the process of change altogether.