WHIT1 (White Mountain, NM, Lat. 33.4698, Long. -105.5227, Alt. 2050) Print-Friendly Version Print-Friendly Version (B&W)
1 year aerosol data are available in White Mountain during the sampling period of 1997 - 2002. As shown in Figure 1, the overall average total light extinction coefficient (Bext) is 28.1 Mm-1 (Visual Range ~ 139 Km; Deciview ~ 10.3). The average PM2.5 mass concentration is 4.2 mg/m3. The average contributions of the major aerosol components to White Mountain haze are particulate sulfate 24.3%, nitrate 5.7%, organic matter (OMC) 13.8%, elemental carbon (light absorbing carbon, LAC) 4.1%, fine soil 3.7% and coarse mass (CM) 12.8%.
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 37.1 Mm-1, which is about 5.6 times of the value of 6.6 Mm-1 during the 20% best days and 2.4 times of the value of 15.3 Mm-1 during the middle 60% days. Sulfate is the largest contributor to aerosol light extinction, with a contribution of 38% in the 20% worst days. OMC and CM also contribute about 20% in the worst days.
Figure 3 suggests that the highest occurrence of the 20% worst days happened in April and June, in which ~ 40% of the sampling days are the 20% haziest days at White Mountain. As shown in Figure 4, OMC is the largest aerosol contributor to haze during the 20% worst days in June, July and October, with a contribution of 22 - 35%. Nitrate is the largest aerosol contributor in December, and CM is the largest in April, with a contribution of 41% and 36%, respectively. Sulfate is an important aerosol contributor to haze the whole year. It contributes about 43% and 58% in August and September, and 20-25% for the rest of the year.
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)
