Impact of NADP/NTN Sampling Protocols on Winter Storm Estimates of Wet Deposition in Central Pennsylvania

摘要

The report describes the field efforts over two snow seasons in central Pennsylvania. Due to a prolonged drought for the past two years, only a limited number of snow/rain events were sampled. The dynamics of the situation are such that conditions found at the central Pennsylvania site are typical for many of the sites in the wet deposition network. The goal of the project was to determine if snow chemistry from samples collected in the Aerochem Metrics sampler (used in the NADP/NTN Network) was representative of the entire event or was it biased due to field sampling difficulties. To evaluate the question, the investigators set up three wet deposition samplers; one that operated in the normal manner (sensor operated), one that operated in the normal manner except that it was manually activated at the start and end of an event, and one that had the collection buckets changed three times during an event. Three precipitation volume collection gauges were also located at the site; one regular gauge, one gauge that had an Alter shield attached, and one that had a Nipher shield attached. Meteorology instrumentation was also installed.