TITLE:
Site Specific Uncertainty in Regional Haze RuleHaze Indexes
AUTHORS:
Patrick A. Ryan
KEYWORDS:
Haze
JOURNAL NAME:
Atmospheric and Climate Sciences,
Vol.2 No.1,
January
19,
2012
ABSTRACT: In 1999, the US Environmental Protection Agency (EPA) published the regional haze rule (RHR). The RHR default implementation plan calls for each class I area 20% worst baseline (2000-2004) visibility to improve linearly in time to natural conditions in 2064 and in calendar year 2018, each class I area 20% worst visibility is to comply with the 2018 visibility that falls on the linear improvement glide path from baseline (2000-2004) to natural (2064) conditions. This study shows that accurately assessing compliance depends on assessing the uncertainty in baseline, natural and 2018 visibility estimates. This study identifies ±3 dV and ±4 dV of uncertainty in 20% worst natural and baseline visibility estimates. The percent uncertainty in calculated 2018 glide path visibility values ranges from 10% - 45%.