Rivers in the United States and other parts of the world are being altered fast because of climate change, confusing native fish species and threatening ecosystems. This is according to a new study by researchers from the United Kingdom. Their findings suggest that that the current human-induced climate crisis is disrupting the global river flow seasonality. River flow occurs at certain periods of the year to provide water security for aquatic life.
The affected bodies of water are particularly located in the northern latitudes of America, Europe, and Russia. The new research paper shows that the seasonal flow of rivers in this part of the northern hemisphere pose a threat to water security and ecosystems. This environmental and ecological disaster not only impacts local aquatic wildlife but also predators that rely on river fish as their source of food.
Changing River Flow
Based on a recent news release by the University of Leeds, climate change has caused 21% of rivers across the globe to show significant signs of alterations when it comes to the seasonal rise and decline in water levels, as cited by the American Association for the Advancement of Science. The UK researchers involved in the research used simulations to determine that changing river flow above 50°N is less likely to match with climatic seasons.
In the research team's study published in the journal Science on February 29, evidence indicates that anthropogenic climate change (caused by greenhouse gas emissions and fossil fuel burning) has started to influence global river flow seasonality. This natural flow pertains to the availability and movement of water that either fills or depletes river levels depending on the season, which also forces fish to migrate.
Anthropogenic Climate Change
The UK study cited previous scientific observations from 1965 to 2014, showing that human impacts on climate have already reduced river flow in the upper parts of the northern hemisphere. The University of Leeds team also emphasized that understanding changes in the global river system is a necessity to ensure that freshwater ecosystems continue their function to provide water resources, both for humans and animals.
Not only anthropogenic climate change alter weather events but it also increases the duration and intensity of drought conditions. The latter leads to reduced precipitation, groundwater recharge, and river instream flows, according to the non-profit environmental organization American Rivers. Over the past year, the impact of climate change on water reservoirs has become evident worldwide, including in North America and Europe.
In Spain, different regions across the country have experienced water shortages as drought struck its water resources, leading to widespread water restrictions. In California, similar restrictions were imposed by local authorities as of June 2023 as a means to conserve water. This is because prolonged drought increases the rate of precipitation but is a natural disaster characterized by a lack of rainfall.
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