OKEF1 (Okefenokee NWR, GA, Lat. 30.7405, Long. -82.1283, Alt. 48) Print-Friendly Version Print-Friendly Version (B&W)
Based on the regional haze rule version 2, 5 years of complete aerosol data are available in Okefenokee NWR during the baseline period of 2000 - 2004. As shown in Figure 1, the overall average total light extinction coefficient (Bext) is 88.6 Mm-1 (Visual Range ~ 55 Km; Deciview ~ 21). The average PM2.5 mass concentration is 9.3 mg/m3. The average contributions of the major aerosol components to Okefenokee haze are particulate sulfate 56.4%, nitrate 5.4%, organic matter (OMC) 16.8%, elemental carbon (light absorbing carbon, LAC) 4.3%, fine soil 0.8%, sea salt 0.7%, and coarse mass (CM) 3.2%.
Figure 1 Average contributions of major aerosol chemical components to light extinction (Based on data available in 2000-2004) (B&W)
Figure 2 Average contributions of major aerosol chemical components to light extinction in 20% best, middle 60% and 20% worst days (Based on data available in 2000-2004) (Data Table) (B&W)
As Figure 2 indicates, the average light extinction coefficient during the 20% worst days is 159.4 Mm-1, which is about 3.4 times of the value of 46.7 Mm-1 during the 20% best days and 2.0 times of the value of 78.3 Mm-1 during the middle 60% days. Sulfate is the largest aerosol contributor to light extinction during the 20% worst days, with a contribution of ~ 65%. OMC also contributes about 19% to light extinction during the 20% worst visibility days.
Figure 3 suggests that the highest occurrence of the 20% worst days happened in May, July, and October, in which over 30% of the sampling days are the 20% haziest days at Okefenokee. As shown in Figure 4, in the 20% worst visibility days, sulfate is the largest aerosol contributor to haze throughout the year.
Figure 3 Percentage of sampling days that are 20% worst days in each month (Based on data available in 2000-2004) (Data Table) (B&W)
Figure 4 Average contributions of major aerosol chemical components to light extinction during 20% worst days in each month (Based on data available in 2000-2004) (Data Table) (B&W)
List of Tables:
1. Number of measurements available in each month during 2000-2004
4. Percentage of worst days happened in each month based on data available during 2000-2004
