BADL1 (Badlands National Park, SD, Lat. 43.7435, Long. -101.9411, Alt. 736)

5 years aerosol data are available in Badlands National Park during the sampling period of 1997 - 2002. As shown in Figure 1, the overall average total light extinction coefficient (Bext) is 35.1 Mm-1 (Visual Range ~ 111 Km; Deciview ~ 12.6).  The average PM2.5 mass concentration is 4.0 mg/m3. The average contributions of the major aerosol components to Badlands National Park haze are particulate sulfate 32.6%, nitrate 9.7%, organic matter (OMC) 13.4%, elemental carbon (light absorbing carbon, LAC) 4.3%, fine soil 1.7% and coarse mass (CM) 9.8%. 

Bext = 35.1 Mm-1

Figure 1 Average contributions of major aerosol chemical components to light extinction (1997-2002)

Figure 2 Average contributions of major aerosol chemical components to light extinction in 20% best, middle 60% and 20% worst days (1997-2002)

As Figure 2 indicates, the average aerosol light extinction coefficient (Bext – Rayleigh Scattering (10 Mm-1)) during the 20% worst days is 46.9 Mm-1, which is about 4.5 times of the value of 10.5 Mm-1 during the 20% best days and 2.1 times of the value of 22.5 Mm-1 during the middle 60% days. Particulate sulfate is the largest contributor to aerosol light extinction during the 20% worst days, and the contribution of particulate sulfate to aerosol light extinction is  ~ 46.7% in worst days. OMC and Nitrate are also responsible for 17.5 and 15.9% of the aerosol light extinction in the 20% worst days. 

Figure 3 suggests that the highest occurrence of the 20% worst days happened in July and August, in which ~35% of the sampling days are the 20% haziest days at Badlands National Park. As shown in Figure 4, Sulfate dominates the aerosol light extinction throughout the year and contributes more than 30% to haze during the 20% worst days. Nitrate is also important in the winter season, while OMC is important in the summer.

Figure 3 Percentage of sampling days that are 20% worst days in each month (1997-2002)

 

Figure 4 Average contributions of major aerosol chemical components to light extinction during 20% worst days in each month (1997-2002)