The drought in the Colorado River Basin goes back further than anyone thought, the U.S. Bureau of Reclamation announced this week.
According to a report recently published in Geophysical Research Letters, a second-century drought is unmatched in severity by the current or previously identified droughts.
“Previous studies have been limited to the past 1,200 years, but a limited number of paleo records of moisture variability date back 2,000 years," Lead Author and Principal Engineer for the Water Resources Engineering and Management Group at the Bureau of Reclamation Subhrendu Gangopadhyay said, according to the release. “While there has been research showing extended dry periods in the southwest back to the eighth century, this reconstruction of the Colorado River extends nearly 800 years further into the past."
Compared to the 22-year drought currently happening in the Colorado River with only 84% water flow, the 22-year water flow in the second century was far lower at 68%, according to the USBR.
“Tree-ring records are sparse back to the second century," Professor at the University of Arizona and a study Co-Author Connie Woodhouse said, according to the release. "However, this extreme drought event is also documented in paleoclimatic data from lakes, bogs, and caves."
Water managers may use this new extended data and the reconstructed streamflow data that was founded in this research to better understand droughts of the past and to plan accordingly for droughts of the future.
Other co-authors for the study include Greg McCabe of the U.S. Geological Survey, Cody Routson from Northern Arizona University and Dave Meko of the University of Arizona, according to the release.
For more information regarding the operations of the Colorado River, visit https://www.usbr.gov/ColoradoRiverBasin/.
