Weekend/Weekday Ozone Observations in the South Coast Air Basin

Figure 2.4-3. Average daily 7-8 a.m. (PDT) CO (ppm) in the SoCAB by day of the week. . 2-21
Figure 2.4-4. Average daily 7-8 a.m. (PDT) NMHC (ppbC) in the SoCAB by day of
the week. ........................................................................................................ 2-22
Figure 2.4-5. Average time (PDT) in the morning when NO equals O 3 by day of
the week. ........................................................................................................... 2-23
Figure 2.4-6. Twelve-site average NO 2 /NOx ratios at 7-8 a.m. (PDT) by day of
the week. ........................................................................................................... 2-24
Figure 2.4-7. Twelve-site average NMHC and NO concentrations at 4-5 a.m. (PDT)
and 7-8 a.m. (PDT) by day of the week. .......................................................... 2-25
Figure 2.5-1. Average time (PDT) at maximum O 3 by day of the week................................. 2-26
Figure 2.5-2. Duration (hours) of ozone accumulation by day of the week. .......................... 2-27
Figure 2.5-3. Ozone accumulation rate (ppb O 3 per hour) by day of the week. ..................... 2-28
Figure 2.5-4. Average duration between t NO=O3 and t maxO3 and average rates of accumulation
of ozone on Sunday and Wednesday during 1981-84 and the differences. ...... 2-29
Figure 2.5-5. Average duration between t NO=O3 and t maxO3 and average rates of accumulation
of ozone on Sunday and Wednesday during 1985-89 and the differences. ...... 2-30
Figure 2.5-6. Average duration between t NO=O3 and t maxO3 and average rates of accumulation
of ozone on Sunday and Wednesday during 1990-94 and the differences. ...... 2-31
Figure 2.5-7. Average duration between t NO=O3 and t maxO3 and average rates of accumulation
of ozone on Sunday and Wednesday during 1995-98 and the differences. ...... 2-32
Figure 2.5-8. Trends in ozone accumulation rate by site for Sunday, Wednesday, and the
difference between Sunday and Wednesday. .................................................... 2-33
Figure 2.5-9. Trends in ozone accumulation rate for western, central, and eastern SoCAB
for Sunday, Wednesday, and the difference between Sunday and Wednesday. 2-34
Figure 2.6-1. Average daily 6-9 a.m. (PDT) NMHC/NOx in the SoCAB by day of
the week. ..................................................................................................... 2-35
Figure 2.6-2. Average daily NMHC/NOx at maximum ozone in the SoCAB by day of
the week. ........................................................................................................... 2-36
Figure 3.1-1a Mean diurnal variations in ozone mixing ratios on Saturdays, Sundays, and
Weekdays at Los Angeles North Main in 1999-2000 and 1980-1998............... 3-21
Figure 3.1-1b Mean diurnal variations in ozone mixing ratios on Saturdays, Sundays, and
Weekdays at Azusa in 1999-2000 and 1980-1998. .......................................... 3-22
Figure 3.1-1c Mean diurnal variations in ozone mixing ratios on Saturdays, Sundays, and
Weekdays at Upland in 1999-2000 and 1980-1998. ......................................... 3-23
Figure 3.1-1d Mean diurnal variations in ozone mixing ratios on Saturdays, Sundays, and
Weekdays at Rubidoux in 1980-1998. .............................................................. 3-24
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