Mar 16 2021
According to an international team of researchers collaborating on a global study with Michigan State University, the availability of water in rivers is largely dependent on climate change like never before.
Image Credit: Michigan State University.
The results of the study could have an intense impact on future food and water security across the globe.
According to Yadu Pokhrel, a co-author of the study and associate professor of civil and environmental engineering in the MSU College of Engineering, climate is the main driver of the present variations in river flow around the world.
It’s a noteworthy finding because as climate change impacts extreme flows, it could be worsening flooding or increasing water scarcity during dry seasons.
Yadu Pokhrel, Study Co-Author and Associate Professor of Civil and Environmental Engineering, College of Engineering, Michigan State University
The new study titled “Globally observed trends in mean and extreme river flow attributed to climate change” has been described in detail in a paper published in Science, an AAAS journal.
Pokhrel added that although flows in rivers and streams can vary year after year, the direction of their flow does not change over long time scales without adverse impacts—caused by human actions or changing climate.
“Previous research has shown that river flows have been changing over time globally but the causes were not known. This study shows that the change in stream flow annually or during droughts was primarily caused by climate change during the past 30 years,” noted Pokhrel.
This suggests that we are on course to lose more and more water in rivers as climate change continues, which could seriously undermine our ability to maintain water supplies for drinking, industries, power generation, and food production.
Yadu Pokhrel, Study Co-Author and Associate Professor of Civil and Environmental Engineering, College of Engineering, Michigan State University
As part of the study, measurements of streamflow at 7,250 locations across the world and computer simulations from nine global hydrological models were used to investigate how human-induced climate change influenced river flows around the world from 1971 to 2010.
The researchers discovered that climate change influenced not only long-term average river flow but also the flow during dry seasons.
It highlights that it is critical to incorporate climate change impacts on water resource planning and management,” Pokhrel added.
Yadu Pokhrel, Study Co-Author and Associate Professor of Civil and Environmental Engineering, College of Engineering, Michigan State University
The study was headed by Lukas Gudmundsson from ETH Zurich, Switzerland.
“This study was possible thanks to the great collaboration between researchers and institutions from 12 countries,” stated Gudmundsson.
Journal Reference:
Gudmundsson, L., et al. (2021) Globally observed trends in mean and extreme river flow attributed to climate change. Science. doi.org/10.1126/science.aba3996.