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I'roendle/Nankcrvis/Porth Page3? 5/22/2003 <br />calibration optimized the simulation of observed changes in stream flow not the stream flow <br />itselt: The new C:"I' modilier coeflicients are prese:nted in 'I'able I. The changes in strearn Ilc?w <br />that have occurred following timber harvest at the Wagon Wheel Gap. Fool Creek, Dead Ilorsc <br />Creek, and Coon Creek watersheds and following toresi disturbance Gum insects and firc on the <br />White River and at JoneS C'reek have been far mure consistent when related to the levcl of <br />disturbancc than have bc:en the actual levels of tlow. 'l'he cunent version of the WRLNSS <br />hydrologic model appears to better estimate observed strcam flow although that stream flow <br />estimate is considerably less than earlier (Troendle and Nankervis 2000) simulations given the <br />same precipitation input (sf:e figure 2). Stream flow estimates and area for each stand class in <br />Table 1. ET modifier coetiicients developed in the re-calihration of the WRF.NSS hydrologic <br />niodel for a 40, 60, and 100 percent reduction in 13asal Area f11er. 'The rnu(iificr <br />cocffiu:ients are linearly interpreted tLtween the points. <br /> BA/BAmax <br />Season A ect 0.0 0.4 0.6 1.0 <br />inter E/VV 1.006 1.005 1.004 1.000 <br />inter N 1.008 1.006 1.005 1.000 <br />inter S 1.055 1.032 1.018 1.000 <br />pring E/W 0_878 0.933 0 958 ? 1 000 <br />pnng N 0.937 0.964 0 974 1.000 <br />pring _ <br />S 0.803 0.881 0.917 1.000 <br />ummer E/W 0.605 0.730 0.780 1.000 <br />ummer N 0.625 0.745 0.795 1.000 <br />ummer S 0.675 0 795 0,825 1 000 <br /> 15 <br /> 14 ' ¦ Swanson: DOS <br />'E 13 . ¦ Nankervis: SAS <br />, <br />v ! I <br /> i <br /> ! <br /> ( <br /> j <br />10 <br />E <br /> <br /> 1?Sl;u 131iu 15UU 1j2U t;,aU I:AA) 1990 1997 2017 <br /> Year <br />h'igure 2. Compazison of the simulated stream flow from National T'orest lands in the North <br />I'latte River Basin for the period 1860 to 1997 using the I)OS niodel ('I'roendle and <br />Nankervis ?000) and the SAS niodel (Appendix B. this document). Strcam flow for <br />2017 was simulated using the SAS niodel only.