BLIS1 (Bliss State Park (TRPA), CA, Lat. 38.9755, Long. -120.1017, Alt. 2116)    

4 year and 8 month aerosol data are available in Bliss State Park (TRPA) during the sampling period of 1997 - 2002. As shown in Figure 1, the overall average total light extinction coefficient (Bext) is 24.3 Mm-1 (Visual Range ~ 161 Km; Deciview ~ 8.9). The average PM2.5 mass concentration is 3.2 mg/m3. The average contributions of the major aerosol components to Bliss State Park (TRPA) haze are particulate sulfate 15.6%, nitrate 6.4%, organic matter (OMC) 22.0%, elemental carbon (light absorbing carbon, LAC) 6.8%, fine soil 2.2% and coarse mass (CM) 5.9%. 

Bext = 24.3 Mm-1

Figure 1 Average contributions of major aerosol chemical components to light extinction (Based on data available in 1997-2002)

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)

As Figure 2 indicates, the average aerosol light extinction coefficient (Bext – Rayleigh Scattering (10 Mm-1)) during the 20% worst days is 27.1 Mm-1, which is about 5.8 times of the value of 4.7 Mm-1 during the 20% best days and 2.1 times of the value of 13.0 Mm-1 during the middle 60% days. OMC is the largest contributor to aerosol light extinction, with a contribution of 43% in the 20% worst days.

Figure 3 suggests that the highest occurrence of the 20% worst days happened in August, in which ~ 50% of the sampling days are the 20% haziest days at Bliss State Park (TRPA). As shown in Figure 4, OMC is the largest aerosol contributor to haze in the 20% worst days from May to December, with a contribution of ~ 30 - 40%. Sulfate is the largest aerosol contributor in March and April, with a contribution of ~ 23% in the worst days. Nitrate is the largest aerosol contributor in January and February, with a contribution of ~ 20 - 30% in the worst days.

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

 

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)