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The Acid Rain Program and the Clean Air Markets Division
The Acid Rain Program, administered by the Clean Air Markets Division, has achieved substantial reductions in emissions of sulfur dioxide (SO2) and nitrogen oxides (NOx), the pollutants that cause acid rain. Created under Title IV of the 1990 Clean Air Act Amendments, Phase I of the program (1995-1999) achieved significant reductions in SO2, beyond the legal limit in almost every affected state. Understanding the environmental response to these emissions reductions is one of the most difficult and important questions remaining. In Phase II, (2000 forward), as even greater reductions in SO2 and NOx occur, the ability to describe the ecological response to these reductions becomes increasingly important in determining whether current control levels provide adequate protection to human health and the environment. Using C-MAP, we can better understand the environmental effectiveness of current air pollution reduction strategies geographically, in order to determine if further pollution control steps may be necessary. There are multiple benefits of reducing acid rain; due to the many receptors in which to track ecological and other responses to current air pollution control strategies, GIS provides a unique tool with which to assess the effectiveness of those efforts.