Wet deposition sampler buckets sit on a silver-colored platform.

This sampler collects rain, snow, and other precipitation as part of the National Atmospheric Deposition Program (NADP) – National Trends Network (NTN). The lid covering the collection bucket opens automatically when moisture is detected on the sensor. When the sensor is dry, the lid automatically covers the sample to prevent evaporation and keep debris out. Park scientists, along with air quality scientists across the country, collect precipitation samples every Tuesday and sending them in for analysis. Scientists interpret data from the samples to determine how much nitrogen and sulfur is being deposited by precipitation in the park.