National Atmospheric Deposition Program NADP

National Atmospheric Deposition Program (NADP), Environment Canada, 05/03/2006, http //nadp.sws.uiuc.edu/date. 

Inputs and outputs to the lake have been measured to calculate net retention for the pre-acidified lake. Precipitation inputs of sulfate were based on data from wet collectors (1980-1983) compiled by the National Atmospheric Deposition Program (NADP). SO2 inputs were calculated from regional ambient air concentrations (22) usinga deposition velocity of 0.5 cm/sec. Aerosol sulfate was estimated from NADP dry bucket measurements and from dry bucket and snow core measurements made in this study (22). Groundwater inputs occur largely at the southeast corner of the lake and were calculated from modeled inseepage (21) and measured sulfate concentrations in a well located in the major inseepage area. Sulfate output was estimated from mean lakewater sulfate concentration and modeled outflows. 

Alaska (PF), Katherine, Australia (KA), Amsterdam Island, Indian Ocean, (AI), and Bermuda, Atlantic Ocean (BD). The eastern U.S. sites include Multistate Atmospheric Power Production Pollution Study (MAP3S) sites at Whiteface Mountain, NY (WH) Ithaca, NY (IT), Pennsylvania State University (PS), Charlottesville, VA (CV) and Urbana, IL (IL). The western states are National Atmospheric Deposition Program (NADP) sites with a continuous record between 1981-1984 (in Colorado, California, Washington, Oregon and Arizona). 

Since 1986, the National Atmospheric Deposition Program (NADP/NTN) has collected weekly precipitation samples from alx>ut 200 monitoring sites nationwide in the United States. Sites are away from major point sources and large urban centers to provide a more regional/national perspective on precipitation chemistry. 

It is interesting to note that the surface used most widely in the United States is the Aerochem-Metrics bucket Since 1982, the buckets have been deployed at over 100 sites nationwide as part of the National Atmospheric Deposition Program (NADP) (8). This monitoring program has resulted in a sizeable dry deposition flux data base for numerous trace element and ionic species (12). 

The vast majority of measurements of nitrogen deposition in the United States—including those made by the National Atmospheric Deposition Program (NADP)—measure only wet deposition (i.e., N in rainfall and... 

Precipitation over North America gradually becomes more acidic from west to east, especially in industrialized areas of the Northeast. This acid rain may be a result of the release of nitrogen and sulfur oxides into the atmosphere. The colors and numbers (see key) indicate pH measured at field laboratories in 2004. Data from National Atmospheric Deposition Program/National Trends Network http //nadp.sws.uiuc.edu. 

National Atmospheric Deposition Program (NRSP-3)/National Trends Network, NADP/NTN Coordination Office, Colorado State University Fort Collins, CO, 1992. 

NADP Quality Assurance Plan for Deposition Monitoring", National Atmospheric Deposition Program, 1984. 

National Atmospheric Deposition Program (1988). NADP/ NTN Annual Data Summary. Precipitation Chemistry in the United States, 1987. National Resources Ecology Laboratory, Colorado State University, Fort Collins, Colorado, 353 pp. 

National Atmospheric Deposition Program/National Trends Network (NADP/NTN) Site Visitation Program for the Period October 1987 through September 1988 Summary Report... 

For example, annual NH4 deposition remains negligible (<1 kgN/ha) nearly everywhere west of the Rocky Mountains, and its peaks around and downwind from the highest concentrations of animals and the most intensive fertilizer applications in the Midwest (Iowa, Illinois, Nebraska) range between 4 and 5 kg N/ha. Annual isopleth maps of U.S. atmospheric deposition can be seen at National Atmospheric Deposition Program, Colorado State University, http //nadp.nrel.colostate.edu/NADP. 

This estimate includes both wet and dry deposition of NOs" and NH4. For the latest map of total wet deposition see National Atmospheric Deposition Program, Colorado State University, http //nadp.nrel.colostate.edu/NADP. 

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