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The Causes of Haze Assessment web is an online report that answers questions about the chemical components that cause regional haze, relationships of haze to meteorology, the emissions that cause haze, and the effects of previous and future emissions reductions on the poorest and best visibility levels.


COHA FAQ link COHA reports link COHA tools link COHA data link About COHA link COHA help link

COHA Resources
The COHA website provides access to virtual reports to answer questions on the causes of haze at all class I areas in the WRAP and CENRAP regions.   (
Mouse-over the icons above for more info.)

  Use the top navigation bar for general information about the website.
  Click on the button "COHA Reports" to navigate to the main reports menu.
  Use the left navigation area to quickly navigate to the reports.
  Learn about the Regional Planning Organizations by following the "Partners" links.
  All bulletins, website changes and news
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  About Air Pollution
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We are constantly seeking to make this website more useful and enjoyable. Please help us with your comments and suggestions...

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Page last updated 13 December 2006