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a7 <br />• ~ from Table 9, and Kc is a crop cover coefficient which, according to <br />Wymore, has a value of 0.5 for bare soil. The constant C is a conver- <br />sion factor which converts Langley/day to inches. Taking an average month <br />to be 30.4 days, C is equal to 0.02053. It was assumed that all snowfall, <br />less evaporation losses in the months Nov.-Mar., accumulates and begins <br />melting in April. Al l• snawpack was assumed to melt in the months of April <br />and May at a rate of 50» per month. These calculations were carried out <br />for a normal year and fora year in which above normal amounts of preci- <br />pitation occurred. These calculations are summarized in Table 10. <br />1! <br />Evaporation during the growing season was estimated using the Jensen- <br />Raise equation as modified by Wymrore {1914): <br />Et Kc [0.014T -,(0.57 - 0.04E1)~ RSC <br />in which EL is the monthly evaporation, Ei is the elevation in thousands <br />of feet, and other symbols are as previously defined. Values of Kc vary <br />• throughout the growing season and are presented in Table 11 along with a <br />r summary of the calculations. <br />TABLE 11 Calculation Of Evaporation With <br />" Water Not Limiting <br />~ Month Kc EL (in.) <br /> <br />Apr .6 2.20 <br />p May .65 3.49 <br />Jun .65 4.65 <br />Jul .65 4.98 <br />1 <br />Aug .6 3.98 <br />Sep .5 2.44 <br />Oct .i 1.42 <br /> 23.16 <br />• The values of Et in Table 11 represent the evaporation that would occur <br />~ if adequate water were available at all times. Actual evaporation, Eta, <br />. depends on water availability and will be computed as a part of the sub- <br />~~I' surface water budget. Clearly, the actual evaporation over the season will <br />be less than the seasonal value of Et shown in Table 11 since the available <br />precipitation 1s 13.15 inches (Table 10). <br />