Regional Haze Progress Assessment 2000-2010

摘要

For many Class Ⅰ areas in the East, visibility improvements are tracking or greater than the uniform rate of progress. For many Class Ⅰ areas in the West, visibility has not improved significantly, despite decreases in anthropogenic emissions of SO_2 and NO_x. This is due to greater percentage contributions from wildfire, dust, and other uncontrollable sources. In future regional haze assessment, better accounting of these uncontrolled sources will be needed.