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<br />75 Suppression = .0299 + .0473 (8 T) <br />R2 = .99 <br /> <br />~ <br />:::.e <br />~ 50 <br />z <br />0 <br />fJ) <br />fJ) <br />w <br />c:: <br />Q. <br />Q. 25 <br />::) <br />fJ) <br /> <br />o <br />o <br /> <br /> <br />2 <br /> <br />4 <br /> <br />6 <br /> <br />10 <br /> <br />8 <br /> <br />CHANGE IN TEMPERATURE (OC) <br /> <br />Figure 9. Model computadon of suppression/water temperature chlllllle functIon. <br /> <br />The nine days of record which were dropped <br />from the analysis had considerable variations in <br />suppression while all the points had similar values <br />for a change in temperature. The scatter was <br />caused by the low temperatures in October and the <br />subsequent low values of evaporation. A regression <br />analysis done on the data broken into three ranges <br />of evaporation showed that the low evaporation <br />values caused most of the fluctuations (Franc- <br />kiewicz, 1975). The analysis of the last nine days of <br />data revealed the error responsible for the <br />fluctuations. The error in the evaporation pan <br />measurement and its effect on the suppression <br /> <br />fonnula accounted for the wide range of values <br />(Appendix A). <br /> <br />Vapor p.....sme subsdtudon <br />error <br /> <br />One factor which would tend to decrease the <br />model suppression value below the correct magni- <br />tude is substitution of saturation vapor pressure of <br />the water (esw) for the saturation vapor pressure of <br />the atmosphere (esa) in the relative humidity <br />component. Long term average pan water tempera- <br />ture should be equal to air temperature for most <br /> <br />20 <br />