1. Tropospheric Ozone Days and Atmospheric Air Mass Relationships in Charlotte, NC and Columbia, SC Casey G. Zuzak University of South Carolina Department of Geography 3 April 2009

2. Outline Background – Ozone/City Selection/Air Mass Background – Ozone/City Selection/Air Mass Data Data Research Questions and Findings Research Questions and Findings Conclusions Conclusions Questions Questions

3. Why Do We Study Ozone? Can cause serious health effects on Humans and Plants Can cause serious health effects on Humans and Plants Human Effects – 2008 Beijing Summer Olympics Human Effects – 2008 Beijing Summer Olympics Respiratory System (Asthma and Emphysema) Respiratory System (Asthma and Emphysema) Eyes Eyes Mucous Membranes in the Nose and Throat Mucous Membranes in the Nose and Throat Plant Effects Plant Effects Reduction in Crop Production Reduction in Crop Production Damage to Leafs and their Processes Damage to Leafs and their Processes Major source of non-drought related crop damage Major source of non-drought related crop damage

5. What is Ozone It is the Allotrope of Oxygen (O 3 ) It is the Allotrope of Oxygen (O 3 ) Discovered in the middle 19 th century Discovered in the middle 19 th century Natural in the Upper Atmosphere, but harmful at the surface Natural in the Upper Atmosphere, but harmful at the surface Produced when the two Primary Pollutants, Nitrogen Oxides and Volatile Organic Material combine to change in sunlight through a series of photochemical reactions to create Secondary Pollutants Produced when the two Primary Pollutants, Nitrogen Oxides and Volatile Organic Material combine to change in sunlight through a series of photochemical reactions to create Secondary Pollutants Secondary Pollutants are what causes the ground level ozone pollution Secondary Pollutants are what causes the ground level ozone pollution Other hazardous byproduct – Peroxyacetyl Nitrate (PAN) Other hazardous byproduct – Peroxyacetyl Nitrate (PAN)

6. How Ozone is Formed NO 2 + sunlight NO + O This free oxygen radical then reacts with O 2 (how oxygen is naturally found) O + O 2 O 3 Ozone is then consumed by nitric oxide to produce nitrogen dioxide and oxygen O 3 + NO NO 2 + O 2 Harmful products such as PAN are produced when nitrogen dioxide is combined with hydrocarbons NO 2 + hydrocarbons PANs The main source of hydrocarbons are VOCs, and when the organic or inorganic oxygenated compounds react with nitric oxide, they produce more nitrogen dioxide NO + Oxygenated Compounds NO 2 + Other products Normally, ozone is consumed, but the when the VOC are present this allows for the chemical reactions to continue

7. Charlotte, NC – Arrowood Station Population Population 671,558 City 671,558 City 2,491,650 CSA 2,491,650 CSA Estimated 24.3 minute commute time Estimated 24.3 minute commute time Weather Observations from Charlotte Douglas International Airport Weather Observations from Charlotte Douglas International Airport Weather Station Ozone Station Downtown 2 mi 2 km

8. Columbia, SC – Congaree Flats Station Population Population 124,818 City 124,818 City 753,663 CSA 753,663 CSA Estimated 17.3 minute commute time Estimated 17.3 minute commute time Weather Observations from Columbia Metropolitan Airport Weather Observations from Columbia Metropolitan Airport Weather Station Downtown Ozone Station 2 mi 2 km

9. Air Mass and Ozone Meteorological Factors Meteorological Factors Cloud Cover Cloud Cover Temperature Temperature Dew Point Dew Point Wind Speed Wind Speed Wind Direction Wind Direction Seasonal Factors Seasonal Factors Summer and Spring have highest surface ozone concentrations Summer and Spring have highest surface ozone concentrations Orographic Factors Valleys versus Mountains Air Mass Effects Anticyclones are most associated with high ozone concentrations Higher Temperatures Light Winds Little Clouds

10. Spatial Synoptic Classification Based solely on surface based observations from individual stations Based solely on surface based observations from individual stations Model that looks at Temperature, Dew Point, Wind, Pressure, and Cloud Cover Model that looks at Temperature, Dew Point, Wind, Pressure, and Cloud Cover Weather Type Classification for over 400 stations in the US and Europe Weather Type Classification for over 400 stations in the US and Europe

11. Dr. Scott Sheridan Classification System ClassGroupDescription DP1 cP Classic air mass…Cold, Clear, and Dry DM2 Moderate and Dry…modified cP DT3 cT Classic air mass…Hot and Dry MP4 mP Classic air mass…Cloudy, Humid, Cool MM5 Warmer and more Humid than MP MT6 mT Classic air mass…Hot and Humid MT+7 Class for MT where mT is usually seen MT++8 Oppressive MT TR9 Transitional throughout the day

12. Data 1 January 2002 to 31 October 2007 1 January 2002 to 31 October 2007 Daily Maximum 8-hour Ozone concentration calculated by the EPA standers Daily Maximum 8-hour Ozone concentration calculated by the EPA standers It is the average of the measured hourly ozone concentrations over an 8-hour period It is the average of the measured hourly ozone concentrations over an 8-hour period Air Mass data from the Spatial Synoptic Classification Air Mass data from the Spatial Synoptic Classification

13. Research Questions How much does population effect tropospheric ozone? How much does population effect tropospheric ozone? What Air Masses are the most prevalent in high ozone days? What Air Masses are the most prevalent in high ozone days? Are there differences in air masses between high ozone days between Charlotte, NC and Columbia, SC Are there differences in air masses between high ozone days between Charlotte, NC and Columbia, SC

14. How Much Does Population Effect Ozone The base population used was the 2006 US Census estimate The base population used was the 2006 US Census estimate The amount of ozone each person was responsible for was calculated The amount of ozone each person was responsible for was calculated Then, the ozone which represented each person was then adjusted by the difference in population between the cities Then, the ozone which represented each person was then adjusted by the difference in population between the cities

15. Base Population for 2006

16. Ozone per Person

17. Adjusted Ozone per Person

18. What Air Masses are Most Prevalent During the Highest Ozone Days Used a One-way Analysis of Variable (ANOVA) test to determine which Air Masses favored days with the highest amount of ozone Used a One-way Analysis of Variable (ANOVA) test to determine which Air Masses favored days with the highest amount of ozone The critical level of ozone was set at 80 ppb, and this is the level that the EPA has determined that its harmful effects would be felt on most humans The critical level of ozone was set at 80 ppb, and this is the level that the EPA has determined that its harmful effects would be felt on most humans Air Masses were determined by the Synoptic Classification System and is broken down into 8 categories Air Masses were determined by the Synoptic Classification System and is broken down into 8 categories Transition days were excluded Transition days were excluded

19. Charlotte, NC Ozone Distribution Distribution of Ozone for Charlotte, NC

20. Distribution of Surface Ozone over the SSC Weather Types – Charlotte, NC Results of ANOVA - CLT

21. Distribution of Ozone for Columbia, SC Columbia, SC Ozone Distribution

22. Distribution of Surface Ozone over the SSC Weather Types – Columbia, SC Results of ANOVA - CAE

23. NCEP Reanalysis on High Difference Days To find the days with the highest difference in tropospheric ozone concentration, the range was found, and the top 5 and the bottom 5 days were looked at (find percent of days) To find the days with the highest difference in tropospheric ozone concentration, the range was found, and the top 5 and the bottom 5 days were looked at (find percent of days) Transition days were included Transition days were included To find these days, the range between ozone concentrations at Columbia, SC and Charlotte, NC was found To find these days, the range between ozone concentrations at Columbia, SC and Charlotte, NC was found

24. Results and NCEP Reanalysis

25. Conclusions Population and Ozone Population and Ozone Charlotte was expected to have a higher adjusted ozone… Charlotte was expected to have a higher adjusted ozone… There was a difference between the city populations versus the CSA population. There was a difference between the city populations versus the CSA population. Difference in ozone due to population is minimal Difference in ozone due to population is minimal Future Research Future Research Examine the origin of the pollutants Examine the origin of the pollutants

26. Conclusions II Charlotte, NC Charlotte, NC High ozone days favor Weather Classification High ozone days favor Weather Classification 2 – Dry and Moderate 2 – Dry and Moderate 3 – Dry and Hot 3 – Dry and Hot 6 – Moist and Hot 6 – Moist and Hot 7 – Extremely Moist and Hot 7 – Extremely Moist and Hot Columbia, SC Columbia, SC High ozone days favor the Weather Classification High ozone days favor the Weather Classification 3 – Dry and Hot 3 – Dry and Hot A lower minimum value for ozone needs to be used in Columbia A lower minimum value for ozone needs to be used in Columbia

27. Dr. Scott Sheridan Classification System ClassGroupDescription DP1 cP Classic air mass…Cold, Clear, and Dry DM2 Moderate and Dry…modified cP DT3 cT Classic air mass…Hot and Dry MP4 mP Classic air mass…Cloudy, Humid, Cool MM5 Warmer and more Humid than MP MT6 mT Classic air mass…Hot and Humid MT+7 Class for MT where mT is usually seen MT++8 Oppressive MT TR9 Transitional throughout the day

28. Conclusions III Columbia, SC Columbia, SC

29. Questions? Questions? Thank you for your attention Contact Information Casey Zuzak zuzak@mailbox.sc.edu (803) 777-1699