Scientific American: A study published this year by Bradley Udall, senior water and climate research scientist with the Colorado Water Institute at Colorado State University, and Jonathan Overpeck, professor of hydrology and atmospheric sciences at the University of Arizona, found that during the drought years of 2000-2014, the river surrendered a third of its flow because of higher temperatures in the upper basin. They were 0.9 degree Celsius above the 1906-1999 average.

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