Table 1.

Estimates of future decrease in runoff in the Colorado River basin due to human-induced climate change

Source	Runoff reduction
Nash and Gleick (1991)	12–31%†
Nash and Gleick (1993)	8–20%
Christensen et al. (2004)	18%
Milly et al. (2005)	10–25%
Seager et al. (2007)	15–20%
Christensen and Lettenmaier (2007)	6–7%
Hoerling and Eischeid (2007)	45%‡
McCabe and Wolock (2007)	8–17%

^†Authors examined a range of values, quoted numbers are for (+2 °C, no change in precipitation) and (+4 °C, −10% precipitation) in the 2-basin model; see original work for details.

^‡Estimate under revision.