7997

• UCREFRP Catalog Number: 7997
• Author: Nash, L. L. and P. H. Gleick.
• Title: The Colorado River Basin and Climatic Change, The Sensitivity of Streamflow and Water Supply to Variations in Temperature and Precipitation.
• USFW Year: 1993.
• USFW - Doc Type: EPA 230-R-93-009,
• Copyright Material: NO

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White River at Meeker
T +4 C Scenarios

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Precipitation Scenario

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Base

Figure 10: Mean annual runoff, mean spring (April, May, June) runoff, and mean fall (October,
November, December) runoff for the White River at Meeker. The base case and T +40C
scenarios are shown.

Transient Scenario

The changes in temperature and precipitation generated by the GISS transient scenario for the

year 2030 fall within the range established by the hypothetical scenarios in which runoff varies linearly with

changes in precipitation. Thus, using the data generated by the hypothetical scenarios, we interpolated to

find correspOnding changes In runoff for the transient scenario. For the more northern GISS grid point,

which encompasses the White River basin, temperature increases by 3.2' C and precipitation increases by

10%. This corresponds to an increase in mean annual streamflow of about 4% on the White River at Meeker

and a significant shift in seasonality. For the southern grid point, which encompasses the Animas and East

river basins as well as the Lake Powell inflow (Two-elevation model), temperature rises by 2.5' C and

precipitation increases by 20%. This corresponds to an increase in mean annual runoff of 12% on the

Animas River, 11 % on the East River, and 9% in the Two-elevation model (inflow into Lake Powell) (Table

9).

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