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a7 <br />from Table 9, and Kc is a crop cover coefficient o-,hich, according to <br />':lymore, has a value of 0.6 for bare soil. The constant C is a conver- <br />sion factor ~,,hich converts Langley/day to inches. Taking an average month <br />to be 30.4 days, C is equal to 0.02053. It v,as assumed that all snowfall, <br />less evaporation losses in the months Yov.-1•lar., accunulotes and begins <br />melting in April. All snowpacY,~•,as assumed to melt in the months of April <br />and play at a rate of 50°S per month. These calculations were carried out <br />for a normal year and for a year in which above normal amounts of preci- <br />~ pitation occurred. These calculations are summarized in Table 10. <br />Evaporation during the growing season o-ras es*_imated using the Jensen- <br />Haise equation as modified by.llymore (1974): <br />Et = Kc [0.014T - {0.57 - 0.04E1;] R5C <br />~ in ~•vhich Et is the monthly evaporation, El is the elevation in thousands <br />of feet, and other symbols are as previously defined. Values of Kc vary <br />throughout the growino season and are presented in Table 11 along with a <br />wi <br />summary of the calculations. <br /> <br />TA3LE 11 Calculation Of Evaporation 'dith <br /> lJater Not Limiting <br />Plonth Kc Et (in. ) <br /> <br />Apr .6 2.20 <br />I I.1ay .65 3.49 <br />Jun .65 4.55 <br />Jul .65 4.93 <br />Aug .6 3.98 <br />' Sep .5 2.44 <br />~ Oct .5 1.42 <br /> 23.16 <br />• The values of Et in Table ll represent the evaporation that would occur <br />if adequate water were available at all times. Actual evaporation. Eta, <br />~.J depends on ,rater availability and •.~ill be computed as a part of the sub- <br />surface water budget. Clearly, the actual evaporation over the season will <br />be less than the seasonal value of Et shoo-rn in Table 11 since the available <br />precipitation is 13.15. inches (Table 10). <br />