DOME1 (Dome Lands Wilderness, CA, Lat. 35.7279, Long. -118.1377, Alt. 925) Print-Friendly Version Print-Friendly Version (B&W)
2 year and 10 month aerosol data are available in Dome Lands Wilderness during the sampling period of 1997 - 2002. As shown in Figure 1, the overall average total light extinction coefficient (Bext) is 42.9 Mm-1 (Visual Range ~ 91 Km; Deciview ~ 14.6). The average PM2.5 mass concentration is 6.3 mg/m3. The average contributions of the major aerosol components to Dome Lands Wilderness haze are particulate sulfate 19.5%, nitrate 17.9%, organic matter (OMC) 19.2%, elemental carbon (light absorbing carbon, LAC) 6.1%, fine soil 2.3% and coarse mass (CM) 11.6%.
Figure 1 Average contributions of major aerosol chemical components to light extinction (Based on data available in 1997-2002) (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 1997-2002) (Data Table) (B&W)
As Figure 2 indicates, the average aerosol light extinction coefficient (Bext – Rayleigh Scattering (10 Mm-1)) during the 20% worst days is 67.9 Mm-1, which is about 8.4 times of the value of 8.1 Mm-1 during the 20% best days and 2.4 times of the value of 28.8 Mm-1 during the middle 60% days. Nitrate is the largest contributor to aerosol light extinction during the 20% worst days, and the contribution of nitrate to aerosol light extinction is ~ 29.7% in worst days. OMC, sulfate and CM also contribute 26.3%, 20.2% and 14.2%, respectively.
Figure 3 suggests that the highest occurrence of the 20% worst days happened in June, August, and October, in which ~35% of the sampling days are the 20% haziest days at Dome Lands Wilderness. As shown in Figure 4, nitrate is the largest aerosol contributor to haze in the winter, with a contribution of more than ~50%. In the summer, OMC is the largest aerosol contributor to haze, and its contribution is about 40-60% in July and August. There is a big peak in Bext during the 20% worst days in July. It happened in one sampling period in July 2002, and dominated by OC/EC, indicating the influence of specific pollution event as forest fire.
Figure 3 Percentage of sampling days that are 20% worst days in each month (Based on data available in 1997-2002) (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 1997-2002) (Data Table) (B&W)
