Ramifications of Charlotte Regional Growth and Weekday Activities on Primary and Secondary Emissions Jenny L. Perry and Patrick M. Owens Department of Chemistry Winthrop University

Objectives Show Charlotte regional growth by traffic volumes Characterize trends in NOy, CO, and Ozone monitoring data Understand how daily traffic fluctuations affect pollutant levels

Approach Taken Characterize daily traffic patterns and growth using available traffic data Examine daily and long-term trends in primary pollutants NOy and CO; relate traffic patterns to primary pollutants Assess emission patterns from power plants Evaluate changes in Ozone concentrations; compare the long-term ozone trend to traffic growth, precursor trends, & temperature

Traffic, Monitor, and Power Plant Sites

Traffic Sites

I-77 Traffic Volume vs Time of Day (June-August 1990-1997) 6000 4000 2000 Time of Day (Hour) Sunday Monday Tuesday Wednesday Thursday Friday Saturday

Fluctuations of Average Traffic Volume (All Sites) 1.25 1.05 S M T W R F SA 7-8 AM 0.85 5-6 PM 0.65 Daily 0.45 0.25 Day of Week

(South Blvd: May-Sept., I-77: June-August) Average Daily Traffic Volume vs Year (South Blvd: May-Sept., I-77: June-August) 75000 65000 55000 45000 South Blvd I-77 35000 25000 15000 1990 1991 1992 1993 1994 1995 1996 1997 Year

I-77 Average Traffic Volume vs Year (June-August) 5500 4750 4000 Hourly 7-8 AM 3250 5-6 PM 2500 1750 1000 1990 1991 1992 1993 1994 1995 1996 1997 Year

South Blvd Average Traffic Volume vs Year (May-September) 3750 3250 2750 Hourly 2250 7-8 AM 1750 5-6 PM 1250 750 1990 1991 1992 1993 1994 1995 1996 1997 Year

Average 7-8 Am CO Concentrations vs Year (May-September 1993-1998) 775 725 675 625 575 County Line 525 Plaza 475 425 375 1993 1994 1995 1996 1997 1998 Year

Concentrations vs Year Average 7-8 AM NO Concentrations vs Year y (May-September 1995-1998) 32 31 30 29 28 County Line 27 Plaza 26 25 24 23 1995 1996 1997 1998 Year

Regional NOx Sources 1997 Gaston County Power Plant Emissions 12,930 tons (Allen) 3,780 tons (Riverbend) 1996 Mecklenburg County Emissions 17,295 tons (mobile sources) 687 tons (stationary sources)

Allen Average NOx Emissions vs Time of Day (May-September 1997-1998) 0.46 0.44 0.42 0.4 0.38 1 3 5 7 9 11 13 15 17 19 21 23 Time of Day Sunday Monday Tuesday Wednesday Thursday Friday Saturday

Allen Plant CO2 Emissions vs Time of Day (May-September 1997-1998) 240 190 140 90 1 3 5 7 9 11 13 15 17 19 21 23 Time of Day Sunday Monday Tuesday Wednesday Thursday Friday Saturday

(Allen and Riverbend Plants, May-Sept. 1997-1998) Fluctuations in Average 7-8 AM CO2 and NOx (Allen and Riverbend Plants, May-Sept. 1997-1998) 1.05 1 S M T-F SA 0.95 CEM CO2 0.9 CEM NOx 0.85 0.8 0.75 Day of Week

Daily Fluctuations of 7-8 AM CO, NOy and Traffic (All Monitors) 1.22 1.12 1.02 0.92 S M T-F SA Noy 0.82 CO 0.72 Traffic 0.62 0.52 0.42 0.32 Day of Week

Daily Fluctuations in Average 1-hr Max O3 (May-Sept. 1990-1998) 1.05 1.03 County Line 1.01 Arrowwood 0.99 S M T-F SA Plaza 0.97 0.95 Day of Week

Daily Fluctuations in O3 by Average Max 8hr (May-September 1990-1998) 1.04 1.02 County Line 1 Arrowwood S M T-F SA Plaza 0.98 0.96 Day of Week

Average May-Sept. High Daily Temperatures 87.5 88 86.8 87 85.6 85.6 86 85 83.6 83.6 83.5 83.1 84 82.1 83 82 81 80 79 1990 1991 1992 1993 1994 1995 1996 1997 1998

Monthly Maximum Temperatures 1990 1991 100 1992 1993 95 1994 90 1996 85 80 1997 1998 75 70 1995 May Jun Jul Aug Sep

July Max Avg Temp and 8 hr O3 Levels 0.08 100 0.07 95 0.06 90 0.05 0.04 85 1990 1991 1992 1993 1994 1995 1996 1997 1998 Max 8Hr Ozone Max Daily Temp

August Max Avg Temp and 8 hr O3 Levels 0.08 92 0.07 0.06 87 0.05 0.04 82 1990 1991 1992 1993 1994 1995 1996 1997 1998 Max 8Hr Ozone Max Daily Temp

Changes in May-Sept Average Daily Maximum 8 Hr Ozone Level

Holiday Fluctuations in 1hr Max O3, & 7-8 AM CO, NOy & Traffic (Labor and Memorial Day, F-R Week, All Monitors, 17 Weeks of O3 Data) 1.55 1.35 1.15 O3 0.95 CO S M T W R F SA 0.75 NOy Traffic 0.55 0.35 0.15 Day of Week

Conclusions Weekend traffic reductions correlate with NOy and to a lesser extent with CO Weekend traffic reduction appears to have little immediate effect on Ozone levels; there seems to be a small cumulative effect from current and previous days’ activities Power production emulates traffic pattern; NOx power plant emissions vary little within each week

Conclusions Average May-Sept daily 7-8 AM NOy and 7-8 AM CO levels in the region appear to be on the rise Average daily maximum Ozone readings at all three monitoring sites in Mecklenburg County have been rising since 1994 Long-term trends in ozone are influenced by temperature

Acknowledgements North Carolina Division of Air Quality (Steve Few, Brian Timin) City of Charlotte Department of Transportation (Charles Able) South Carolina Department of Transportation (Joe Boozer)

Additional Supporting O3 and Temperature Graphs O3 and temperature graphs for the months of May, June and September follow. The months of July and August are depicted in the presentation.

May Max Avg Temp and 8 hr O3 Levels 0.07 88 83 0.06 78 0.05 73 1990 1991 1992 1993 1994 1995 1996 1997 1998 Max 8Hr Ozone Max Daily Temp

June Max Avg Temp and 8 hr O3 Levels 0.075 96 91 0.065 86 0.055 81 0.045 76 1990 1991 1992 1993 1994 1995 1996 1997 1998 Max 8Hr Ozone Max Daily Temp

September Max Avg Temp and 8 hr O Levels 3 0.075 86 0.065 0.055 81 0.045 0.035 76 1990 1991 1992 1993 1994 1995 1996 1997 1998 Max 8Hr Ozone Max Daily Temp