||Illinois State Water Survey Div., Champaign.; Illinois Univ. at Urbana-Champaign.; Department of Agriculture, Washington, DC.; Department of the Interior, Washington, DC.; Environmental Protection Agency, Washington, DC.
The National Atmospheric Deposition Program (NADP) provides data that support informed decisions on air quality issues related to precipitation chemistry. Scientists, educators, policy-makers, and the public use NADP data via the NADP web site. This site enables on-line retrieval of individual data points, seasonal and annual averages, trend plots, concentration and deposition maps, reports, and other information. In 2006, the number of registered Web site users rose to nearly 33,000, representing 154 countries. Data downloads numbered 23,664, an increase of 27 percent from 2005. Users logged nearly 350,000 sessions, and the number of color concentration and deposition maps viewed in 2006 rose by nearly 30 percent, topping 121,000.