A study reveals similar trends in streamflow in natural and human-modified watersheds. Climate change can alter streamflow volume and variability worldwide, thereby influencing human systems ranging from agricultural to urban environments. However, human modifications to water systems, such as dams and land-cover change, are thought to mask streamflow changes associated with climate fluctuations. Darren L. Ficklin and colleagues explored differences in streamflow in natural and human-modified watersheds in Canada and the United States from 1981 to 2015. The study incorporated streamflow data, including metrics related to typical daily streamflow, variability of daily streamflow, and daily extremes in streamflow, from more than 3,000 watershed sites. Following statistical analysis of the data, the authors report similar trends in streamflow metrics in both natural and human-modified watershed systems. Overall, streamflow decreased in the southern and western United States and increased in the northeastern United States, northern Great Plains, and southern prairies of Canada. Using climate data, the authors linked the findings to local precipitation and evapotranspiration patterns. According to the authors, the study suggests that changes in climate are evident across streamflow systems, despite water-resource management in human-modified watersheds.
Article #18-01026: "Natural and managed watersheds show similar responses to recent climate change," by Darren L. Ficklin, John Abatzoglou, Scott Robeson, Sarah Null, and Jason Knouft.
MEDIA CONTACT: Darren L. Ficklin, Indiana University Bloomington, IN; tel: 812-856-5047; e-mail: < dficklin@indiana.edu >
###
Proceedings of the National Academy of Sciences