Comparison of Snowfall Between A Standard Precipitation Gauge and Snow Board Measurements

The measurement of snowfall precipitation is important for ecosystem and watershed research, and avalanche forecasting. Obtaining accurate measurements of solid precipitation, or snow, remains challenging. Literature values suggest that measurement errors can range from 20% to 80% due to undercatch resulting from wind and other such variables. Some sources report overcatch. In 2007 a site was established by the Rocky Mountain Research Station on the Fraser Experimental Forest in the north central rocky mountain region of Colorado to compare snowfall between an unshielded standard Belfort Universal Gauge and snow board snow core measurements. The period of record for this study was within the winter months, defined by the accumulation of measurable snow typically between November and May, and including the water years of 2008 through 2012. Catch comparisons were made for 24 hour event periods. In addition, comparisons were made for annual accumulation of snow water equivalence between the gauge and the snow board. The null hypothesis was that catch deficiency in the unshielded Belfort Universal Gauge is statistically insignificant compared to snow board measurements for individual events, as well as the annual cumulative total for the winter months. The relationship between the event catch of the rain gauge and the snow board measurements was nearly one to one, and an R² close to 0.94. Seasonal differences of 4% on average were statistically significant with the rain gauge undermeasuring solid precipitation.