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

decreases in runoff (of -8% to -10%); this is related to the grid point used. Using the Two-elevation model,

three of the four GeM scenarios resulted in decreases in mean annual runoff ranging of -14% and -24%. The

fourth scenario resulted in an increase of less than 1 %.

Table 5: Annual inflow (tat) into lake Powell (Two-elevation model) for all scenarios.

Scenario

Mean (1]

so

cv

Minimum

Maximum

Base 10940 2983 0.27 4481 17040
T+20 P-l0oAl 8386 (-23.3OAl) 2418 0.29 3357 (-25.1%) 12940 (-24.1 %)
T+20 P+O 9656 (-11.70Al) 2727 0.28 3924 (-12.4%) 14330 (-15.5OIb)
T+20 P+l0% 11000 (0.6%) 3046 0.28 4504 (0.501b) 16350 (-4.0oAl)
T+40 P-20oAl 6447 (-41.0oAl) 1970 0.31 2520 (-43.8%) 11480 (-32.6%)
T+40 P-l0% 7522 (-31.2%) 2260 0.30 2892 (-35.5OAl) 12480 (-26.8%)
T+40 P+O 8668 (-20.7%) 2554 0.30 3373 (-24.0%) 13490 (-20.8%)
T+40 P+l0oAl 9879 (-9.7%) 2854 0.29 3911 (-12.7%) 14530 (-14.8OAl)
T+40 P+20% 11150 (2.0%) 3162 0.28 4443 (-0.9%) 16180 (-5.1%)
GISS2 9444 ( -13.6OIb) 2804 0.30 3624 (-19.1OIb) 14220 (-16.5OIb)
GFOL 8369 (-23.5%) 2514 0.30 3180 (-29.001b) 13270 (-22.10Al)
UKMO 1 10950 (0.2%) 3240 0.30 4107 (-8.3OIb) 16070 (-5.7OIb)
UKMO 2 8639 ( -21.001b) 2693 0.31 3173 (-29.2%) 13926 (-18.3OIb)

Note: (1) Numbers in parentheses represent percent change from the base case.

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