Snow volume comparisons for atmospheric deposition monitoring

Chemical loading due to atmospheric deposition depends on both snowfall volume and chemistry. At a forest clearing in the central Sierra and at a windy site in the southern Sierra Nevada, precipitation, air temperature, wind direction and speed, and humidity were recorded. At the sheltered site, precipitation volumes from replicated shielded and unshielded Belfort gauges were similar. The experimental collector's volumes were similar to the Belfort's volumes. At the windy site, the daily and weekly snow boards collected more snow than the experimental or Belfort collectors. At the forest site, the inability of the snow boards to retain rain and melt caused their seasonal totals to be less than the other devices. The traditional 'wet-dry' precipitation collector worked well at the sheltered site, but only with frequent servicing by technicians. This 1-year study showed that uniform procedures will not produce accurate volume and chemical concentration data at sites with different physical characteristics.