Regional haze

Regional Haze a cloud of aerosols extending up to hundreds of miles across a region and promoting noticeably hazy conditions. 

Regional Haze Visibility Impairment any humanly perceptible change in visibility (light extinction, visual range, contrast, coloration) from that which would have existed under natural conditions, caused predominantly by a combination of many sources from, and occurring over, a wide geographic area. 

SO3 control is also an increasingly important issue for refinery FCC operators. Regional haze, PMj 5, hazardous air pollutants, and visible stack emissions all in some way relate to SO3. The present level of control achievable in wet scrubbers is limited. However, use of wet ESPs integral to the scrubber has been used commercially. 

Other important inputs to AQM are the transformation and deposition processes of air pollutants. Examples of air quality modeling where transformation and deposition processes need to be considered are acid deposition, regional haze, and photo-oxidants. 

Fig. 2. Regional haze in the Vermont Green Mountains. Note as the pollution episode progresses, adjacent peaks are no longer visible. (Photo by the Vermont Agency of Environmental Cbnservatioa)...

The major concern for the region is the open burning of domestic wastes and forest fires in the tropical forest belt of Southeast Asia that resulted in severe hazes and the release of hazardous airborne chemicals, particularly PAHs. It became such a regional crisis that a Regional Haze Action Plan was instituted in 2001 to address the issue of transboundary haze (ASEAN, 2006). 

ASEAN, 2006. Regional haze action plan. Available at http //www.aseansec.org/9059.htm accessed on April 24, 2006. 

Eaton P. and Radojevic M. (eds.) (2(X)1) Forest Fires and Regional Haze in Southeast Asia. Nova Science, Huntington, NY, 280pp. 

US EPA. (1997). Regulatory Impact Analyses for the Particulate Matter and Ozone National Ambient Air Quality Standards and Proposed Regional Haze Rule. Office of Air Quality Planning and Standards, Research Triangle Park, NC. 

Figure I. Approximate location of forest fire hot-spots and area affected hy regional haze in Southeast Asia (Radojevic and Tan, 2000).

The harmful effects of regional haze episodes have caused considerable concern to the government authorities and the public in Brunei. Effects of the haze include a drastic... 

Radoejvic M. and Tan K. S., 2000. Impacts of biomass burning and regional haze on the pH of rainwater in Brunei Darussalam. Atmospheric Environment, 34, 2739-2744. 

White, W. H., and Macias, E. S. (1989) Carbonaceous particles and regional haze in the Western United States, Aerosol Sci. Technol. 10, 106-110. 

Table 10.1. Comparison of major provisions of S.366 (Jeffords/Lieberman/Collins), S.843 (Carper, Gregg, Chafee), S. 485 (Bush Administration), EPA 2001 Proposal, and EPA Proposed Interstate Air Quality, Regional Haze, and Mercury MACT Rules... 

Proposed Interstate Air Quality Rule, Regional Haze/ Best Available Retrofit Technology (BART) Rule, and Mercury Rule 2.4 million ton cap by 2010 2.1 million ton cap by 2015 4.6 million ton cap by 2010 3.5 million ton cap by 2015 MACT proposal 34 tons by 2008 Section 112(n) trading alternative 34 tons by 2010 Section 111 cap and trade alternative 34 tons by 2010 and 15 tons by 2018 No limit on COj emissions Final rule may include NSR rollbacks N/A... 

Regional Haze Haze produced by a multitude of sources and activities that emit fine particles and their precursors across a broad geographic area. National regulations require states to develop plans to reduce the regional haze that impairs visibility in national parks and wilderness areas. 

EPA also has the authority to require states to include air quality goals other than the NAAQS in their implementation plans regional haze programs are one example. Oil and gas operations can produce haze precursors, or pollutants that reduce visibility, including NO2, SO2, and particulate matter. 

Morris RE, Koo B, Guenther A, Yarwood G, McNally D, Tesche TW, Tonnesen G, Boylan J, Brewer P (2006) Model sensitivity evaluation for organic carbon using two multi-pollutant air quality models that simulate regional haze in the southeastern United States. Atmos Environ 40 4960-4972... 

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