2. City and Regional Planning / The Ohio State University IMPACTS OF TRAFFIC VOLUMES AND WIND DIRECTIONS ON AIR POLLUTION CONCENTRATIONS IN SEOUL, KOREA Youngkook Kim * Jean-Michel Guldmann * Hui-Mun Ra** * Ph.D. Candidate and Professor in Department of City and Regional Planning, OSU ** Assistant Professor in Dept. of Public Administration, Sungkyul University, Anyang, S. Korea 10. 6. 2008

3. 2 / 16 Introduction Impacts of Traffic Volumes and Wind Directions on Air Pollution Concentrations in Seoul, Korea YOUNGKOOK KIM / JEAN-MICHEL GULDMANN / HUI-MUN RA Research Method Traffic vs. Pollution Conclusion Wind Direction Impacts I. Introduction 1 Transportation is known to be responsible for a substantial share of urban air pollution such as carbon monoxide (CO), nitrogen oxides (NO x ), volatile organic compounds (VOC), particulate matter (PM), and sulfur dioxide (SO 2 ), a) Sources: EPA (2000), Korea Ministry of Environment (2005) b) Includes on-road and off-road engines and vehicles. c) Includes on-road vehicles only. Share of emission from transportation CONO 2 VOCPM10SO 2 US b) 79 %53 %43 %19 %7 % South Korea c) 79.4 %42.2 %16.7 %43.4 %1.3 % Seoul c) 90.0 %61.1 %31.1 %73.8 %11.0 %

4. 3 / 16 Introduction Impacts of Traffic Volumes and Wind Directions on Air Pollution Concentrations in Seoul, Korea YOUNGKOOK KIM / JEAN-MICHEL GULDMANN / HUI-MUN RA Research Method Traffic vs. Pollution Conclusion Wind Direction Impacts  Estimate hourly VKT around air quality monitoring stations (AQM)  Hourly VKTs are weighted by wind direction frequencies  The relationships between AQM pollution concentrations, WD- weighted and un-weighted VKTs are investigated Purposes It is reasonable to expect that, as vehicle-kilometers-traveled (VKT) increase, ambient air pollution concentrations also increase. 1

5. 4 / 16 Introduction Impacts of Traffic Volumes and Wind Directions on Air Pollution Concentrations in Seoul, Korea YOUNGKOOK KIM / JEAN-MICHEL GULDMANN / HUI-MUN RA Research Method Traffic vs. Pollution Conclusion Wind Direction Impacts II. Research Method & Data 2 Location of AQMs, Circular Buffers, and Assigned Traffic Flows

6. 5 / 16 Introduction Impacts of Traffic Volumes and Wind Directions on Air Pollution Concentrations in Seoul, Korea YOUNGKOOK KIM / JEAN-MICHEL GULDMANN / HUI-MUN RA Research Method Traffic vs. Pollution Conclusion Wind Direction Impacts II. Research Method & Data Research framework 2

7. 6 / 16 Introduction Impacts of Traffic Volumes and Wind Directions on Air Pollution Concentrations in Seoul, Korea YOUNGKOOK KIM / JEAN-MICHEL GULDMANN / HUI-MUN RA Research Method Traffic vs. Pollution Conclusion Wind Direction Impacts 2 Wind direction data

8. 7 / 16 Introduction Impacts of Traffic Volumes and Wind Directions on Air Pollution Concentrations in Seoul, Korea YOUNGKOOK KIM / JEAN-MICHEL GULDMANN / HUI-MUN RA Research Method Traffic vs. Pollution Conclusion Wind Direction Impacts 2 Wind direction impacts on VKT

9. 8 / 16 Introduction Impacts of Traffic Volumes and Wind Directions on Air Pollution Concentrations in Seoul, Korea YOUNGKOOK KIM / JEAN-MICHEL GULDMANN / HUI-MUN RA Research Method Traffic vs. Pollution Conclusion Wind Direction Impacts 3 1) Hourly NO 2 concentrations and Traffic Counts III. Traffic flows vs. Pollution concentration

10. 9 / 16 Introduction Impacts of Traffic Volumes and Wind Directions on Air Pollution Concentrations in Seoul, Korea YOUNGKOOK KIM / JEAN-MICHEL GULDMANN / HUI-MUN RA Research Method Traffic vs. Pollution Conclusion Wind Direction Impacts 3  Positive impacts on NO 2 concentration III. Traffic flows vs. Pollution concentration  Negative impacts on NO 2 concentration

11. 10 / 16 Introduction Impacts of Traffic Volumes and Wind Directions on Air Pollution Concentrations in Seoul, Korea YOUNGKOOK KIM / JEAN-MICHEL GULDMANN / HUI-MUN RA Research Method Traffic vs. Pollution Conclusion Wind Direction Impacts 3 2) Hourly CO concentrations and Traffic Counts III. Traffic flows vs. Pollution concentration

12. 11 / 16 Introduction Impacts of Traffic Volumes and Wind Directions on Air Pollution Concentrations in Seoul, Korea YOUNGKOOK KIM / JEAN-MICHEL GULDMANN / HUI-MUN RA Research Method Traffic vs. Pollution Conclusion Wind Direction Impacts 3 3) Hourly SO 2 concentrations and Traffic Counts III. Traffic flows vs. Pollution concentration

13. 12 / 16 Introduction Impacts of Traffic Volumes and Wind Directions on Air Pollution Concentrations in Seoul, Korea YOUNGKOOK KIM / JEAN-MICHEL GULDMANN / HUI-MUN RA Research Method Traffic vs. Pollution Conclusion Wind Direction Impacts 3 4) Hourly PM10 concentrations and Traffic Counts III. Traffic flows vs. Pollution concentration

14. 13 / 16 Introduction Impacts of Traffic Volumes and Wind Directions on Air Pollution Concentrations in Seoul, Korea YOUNGKOOK KIM / JEAN-MICHEL GULDMANN / HUI-MUN RA Research Method Traffic vs. Pollution Conclusion Wind Direction Impacts 3 5) Hourly O 3 concentrations and Traffic Counts III. Traffic flows vs. Pollution concentration

15. 14 / 16 Introduction Impacts of Traffic Volumes and Wind Directions on Air Pollution Concentrations in Seoul, Korea YOUNGKOOK KIM / JEAN-MICHEL GULDMANN / HUI-MUN RA Research Method Traffic vs. Pollution Conclusion Wind Direction Impacts IV. Wind Direction Impacts 4

16. 15 / 16 Introduction Impacts of Traffic Volumes and Wind Directions on Air Pollution Concentrations in Seoul, Korea YOUNGKOOK KIM / JEAN-MICHEL GULDMANN / HUI-MUN RA Research Method Traffic vs. Pollution Conclusion Wind Direction Impacts IV. Wind Direction Impacts 4

17. 16 / 16 Introduction Impacts of Traffic Volumes and Wind Directions on Air Pollution Concentrations in Seoul, Korea YOUNGKOOK KIM / JEAN-MICHEL GULDMANN / HUI-MUN RA Research Method Traffic vs. Pollution Conclusion Wind Direction Impacts 5 V. Conclusion Positive relationships with NO 2, SO 2, CO, and PM10 concentrations On the other hand, O 3 concentration is negatively correlated with VKTs  Relations between hourly VKTs and air pollution concentration WD-weighted VKTs increase explanatory powers in most cases In the case of O 3, however, WVKTs during the afternoon 8 hours do not enhance model predictability, which calls for further research  WD-weighted impacts on pollution concentration