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<br />The test clearing was on a hillside which sloped upward toward the southwest, the most <br />common wind direction. Sustained periods with winds of 4 to 6 mph were observed between <br />some storms. Winds might have been stronger near the surface than at gauge height because <br />of lack of conifer branches near the ground. Therefore, the possibility exists that downslope <br />drifting of snow onto the snowboard sometimes occurred in spite of the light winds recorded <br />during snowfall at gauge orifice height. This possibility illustrates the difficulty of measuring <br />the actual snowfall even within a sheltered clearing in the forest. <br /> <br />CONCLUSIONS <br /> <br />The ETI precipitation gauge proved to be reliable and provided good quality data. The only <br />problem was an occasional tendency for the gauge to falsely indicate minor snowfall amounts, <br />usually 0.01 in. snow water equivalent, during relatively warm midday periods. This problem <br />is suspected to be caused by inadequate compensation of the load cell's temperature <br />dependence. Otherwise, the gauge compared very well with a nearby calibrated Belfort <br />weighing gauge. If one ignores the hours when the ETI gauge indicated precipitation but the <br />Belfort did not, the total accumulation by the two gauges was very similar. The two gauges <br />rarely differed in hourly precipitation amount by more than 0.015 in. <br /> <br />Agreement between the two gauges was better than between either gauge and a nearby <br />snowboard. Although the snowboard observations were higWy correlated with both gauges, <br />the snowboard received from 6 to 9 pct more snowfall than the gauges over the test period. <br />Part of this difference may have been caused by gauge undercatch, although wind speeds <br />were very limited during snowfall in the protected test clearing. It is speculated that part <br />of the difference may have been caused by downhill drifting of snow onto the snowboard <br />between some storms. <br /> <br />The observations indicate that either the ETI or Belfort gauge can provide accurate <br />precipitation measurements when protected from significant wind. The ETI gauge has the <br />advantages of requiring infrequent servicing and providing digital, computer-compatible data <br />without laborious manual chart reading. <br /> <br />4 <br />