(BRAVO) Study: Final Report. - Desert Research Institute
(BRAVO) Study: Final Report. - Desert Research Institute
(BRAVO) Study: Final Report. - Desert Research Institute
You also want an ePaper? Increase the reach of your titles
YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.
<strong>Final</strong> <strong>Report</strong> — September 2004<br />
Light Extinction Attribution (1/Mm)<br />
100<br />
80<br />
60<br />
40<br />
20<br />
0<br />
Sulfate Haze Source Attribution<br />
Carbón Other Mexico<br />
Texas Eastern US<br />
Western US Other<br />
Clear Air<br />
Organics + LAC + Nitrates +<br />
Fine Soil + Coarse<br />
July 9 August 9 September 9 October 9<br />
Light Extinction Attribution<br />
100%<br />
90%<br />
80%<br />
70%<br />
60%<br />
50%<br />
40%<br />
30%<br />
20%<br />
10%<br />
0%<br />
July 9 August 9 September 9 October 9<br />
Figure 1-9. Estimated contributions to light extinction by various particulate sulfate source regions.<br />
The top plot shows the absolute haze contributions by the various particulate sulfate sources as well as<br />
the total light extinction level (black line) and Rayleigh or clear air light scattering. The bottom plot<br />
shows the fractional contribution to light extinction by the various particulate sulfate sources and by<br />
Rayleigh light scatter (top-most on the plot), which is relatively more important on the clearest days.<br />
The contributions to light extinction by particle free air (i.e., Rayleigh scattering) are shown explicitly<br />
since they represent a natural limit that cannot be improved upon.<br />
Texas<br />
10 (11)%<br />
Other<br />
Mexico<br />
6 (7)%<br />
Carbón<br />
8 (9)%<br />
1/5 Haziest <strong>BRAVO</strong> Days<br />
Sulfate Haze<br />
47 (55)%<br />
Non-<br />
Sulfate<br />
Haze<br />
38 (45)%<br />
Eastern US<br />
19 (22)%<br />
Clear Air<br />
15%<br />
Western<br />
US 3 (4)%<br />
Other<br />
2 (3)%<br />
Carbón<br />
4 (8)%<br />
1/5 Least Hazy <strong>BRAVO</strong> Days<br />
Other<br />
Mexico<br />
6 (11)%<br />
Non-<br />
Sulfate<br />
Haze<br />
32 (61)%<br />
Texas<br />
2 (4)%<br />
Sulfate Haze<br />
21 (39)%<br />
Eastern<br />
US 3 (5)%<br />
Clear Air<br />
48%<br />
Western<br />
US 3 (6)%<br />
Other<br />
3 (5)%<br />
Average B ext = 66 1/Mm<br />
Average Bext = 20 1/Mm<br />
Figure 1-10. Estimated contributions by particulate sulfate source regions to Big Bend light extinction<br />
levels for the 1/5 haziest days and the 1/5 least hazy days of the <strong>BRAVO</strong> <strong>Study</strong> period. Percent<br />
contributions to particulate haze (non-Rayleigh light extinction) are shown parenthetically.<br />
1-15
Change language