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Fall/Early Winter Correlation, r = 0.63, is higher than for
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ICF/DCF = Ratio of the amount that flow increases to the amount
that flow decrease over a season (e.g., fall/early winter).
Figure 4 shows that:
As early as Nov, the amount that flows increases compared
to the amount that flow decreases (i.e., ICF/DCF) over the
month correlates strongly (r = 0.71) with ABY, or spring
snowmelt runoff.
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Results suggest that:
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(1) Assume that major climate modes influencing
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precipitation and temperature in the UCRB are established
accumulates; and
(3) Characterize streamflow response to precipitation and
temperature signals between fall and early spring.
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by fall and persist into spring;
(2) Start analysis in the fall, before snow typically
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Acknowledgements: U.S. Bureau of Reclamation funded the original project upon which this research is based.
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(1) Climate modes influencing precipitation & temperature in
the UCRB are established by fall & persist into spring; (2)
Streamflow amplifies effects of climate signals; and (3)
Effects of interannual climate signals on precipitation are
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detectable in streamflow as early as fall.
5. References
1. Cayan, D.R., Redmond, K.T., and Riddle, L.G. 1999. ENSO and hydrologic extremes in the western
United States. Journal of Climate 12: 2881-2893.
2. Gutzler, D.S. and Rosen, R.D. 1992. Interannual variability of wintertime snow cover across the
Northern Hemisphere. Journal of Climate 5: 1441-1447.
3. Hidalgo, H.G. and Dracup, J.A. 2003. ENSO & PDO effects on hydroclimatic variations of the Upper
Colorado River Basin. Journal of Hydrometeorology 4: 5-23.
Corresponding author: Margaret Matter, e-mail address: mmatter@lamar.colostate.edu