National Atmospheric Deposition Program

The National Atmospheric Deposition Program (NADP) is a nationwide precipitation chemistry monitoring network and a cooperative effort between many different groups, including the NPS, USDA, State Agricultural Experiment Stations, U.S. Geological Survey, Environmental Protection Agency, U.S. Fish and Wildlife Service, and numerous universities and other governmental and private entities. The purpose of the network is to collect data and monitor geographical patterns for long-term trends in precipitation chemistry. The precipitation at each site is collected weekly according to strict clean-handling procedures. It is then analyzed at a central laboratory. Stringent quality assurance and quality control programs ensure that the data are accurate and precise. More information on these programs and the monitoring data can be found on the NADP website at https://nadp.slh.wisc.edu.