1. 1 Prediction of Air Quality over Tokyo Metropolitan Area by Using the JCAP II Air Quality Simulation System Presented at the 6th Annual CMAS Conference, Chapel Hill, NC, October 1-3, 2007 Satoru Chatani 1, Tazuko Morikawa 1, Midori Ashizaki 1, Hideki Tashiro 1, Hitoshi Kunimi 1, Hiroshi Hirai 2 and Satoshi Yamazaki 3 1. Japan Petroleum Energy Center, Minato-ku, Tokyo, JAPAN 2. Japan Automobile Research Institute, Tsukuba, Ibaraki, JAPAN 3. Toyota Central R&D Labs., Inc., Nagakute, Aichi, JAPAN

2. 2 Joint research project (Japanese version of the Auto-Oil program) to improve air quality Petroleum industryAutomobile industry What is JCAP? (Japan Clean Air Program)

3. 3 Objectives of Air Quality Studies in JCAP II (2002.4 - 2007.3) Develop the air quality modeling system and data; -Simulate multi-scale air quality (from Asia to roadside) -Reflect real-world driving conditions -Contribute to the policymaking -Open to the public (de facto standard in Japan) Analyses using the system were report to the policymaking process.

4. 4 Structure of the Modeling System Details of our system is presented at the poster session in tomorrow evening !! Macro-scale traffic flow model Micro-scale traffic flow model Macro-scale vehicle emission inventory model Micro-scale vehicle emission inventory model Multiscale air quality model Roadside air quality model Meteorological model Secondary organic aerosol model Emission inventory except for vehicles Aerosol dynamic model Measurement of aerosol characteristics Air pollution including nano- particles for roadside to urban / regional area Evaluation of contribution from vehicles

5. 5 Current Status of NO 2 in Japan Average conc. (ppb) NAAQS Attainment (Polluted area specified by the automobile NOx-PM law) Some roadside stations still exceed NAAQS of NO 2. AmbientRoadside

6. 6 Current Status of SPM in Japan (SPM : Suspended Particulate Matter, equivalent to PM7) (Polluted area specified by the automobile NOx-PM law) Average conc. (  g/m 3 ) NAAQS Attainment NAAQS attainment varies (partly due to Asian dust). AmbientRoadside

7. 7 Application of the Modeling System Air quality model CMAQ v4.6 Meteorological model RAMS v4.4 Emission inventory (Japan) Vehicle : JCAP II Other sources : EAGrid-2000 (Kannari, 2007) (Outside Japan) REAS (Ohara, 2007), GEIA (Granier, 2005)

8. 8 Target Domains of the Simulation 1,088km 1,024km 160km 176km 7,296km Asia Mesh 64 x 64 km Japan G1 Mesh 16 x 16 km Japan G2 Mesh 4 x 4 km Main target area (Tokyo and surrounding area)

9. 9 Estimation of Vehicle Emissions JCAP II Urban Motor Vehicle Emission Inventory Model Emission processes:Running, Cold-start, Evaporative (Running loss, Hot soak loss, Diurnal breathing loss), Road dust and Tire wear Pollutants:CO, NOx, SO 2, THC, SPM, SO 4 2-, NH 3 Emission = Emission Factor * Traffic Amount Category, model year, speed, deterioration, temperature and humidity Category, model year, speed, mesh and hour

10. 10 Traffic Amounts in Meshes Digital Road Map (DRM) No.LengthTraffic… 11.010,000… 20.53,000… ………… Census data (by Government) Matching 10 x 10 km (Whole Japan) 1x1 km (Around Tokyo) Gridding by GIS Traffic amount in meshes

11. 11 RSD for Identifying High-emitters Real-world emission measurement by RSD (Remote Sensing Devices) Average conc. and distribution (NO, PC) Ratio of High-emitters was calculated and used for estimation.

12. 12 Distribution of Pollutant Emissions (Whole Japan, NOx in December) VehiclesOther Anthropogenic

13. 13 Distribution of Pollutant Emissions (Around Tokyo, NOx in December) VehiclesOther Anthropogenic

14. 14 Simulation Cases Target period of the simulation : Nov. 1 st to Dec. 10 th, 1999

15. 15 Estimated NOx Emissions VehiclesAll Sources Gasoline REDiesel RE Gasoline STDiesel ST StationaryDomestic MobileVehicles Emission is largely reduced by replacement. Excluding High-emitters are effective than new regulations. (Summed over the target area)

16. 16 Estimated SPM Emissions VehiclesAll Sources Road dustDiesel RE Tire wearDiesel ST Road dust and tire wear become major SPM sources. New regulations have negligible effects. StationaryDomestic Mobile Vehicles Road dust Tire wear (Summed over the target area)

17. 17 Simulated NO 2 Distribution 070 (ppb) ObservationSimulation

18. 18 Simulated SPM Distribution 0 80 (  g/m 3 ) ObservationSimulation

19. 19 Time Series of Concentrations (At stations within Tokyo metropolitan area) ObservationSimulation

20. 20 Performance of NO 2 Simulation MNE : Mean Normalized Error MNB : Mean Normalized Bias MNEMNB > 0MNB < 0 Average within the target area MNB : -17.9%, MNE : 21.1%

21. 21 Performance of SPM Simulation MNE : Mean Normalized Error MNB : Mean Normalized Bias MNEMNB > 0MNB < 0 Average within the target area MNB : -51.4%, MNE : 53.3%

22. 22 Predicted Pollutant Concentrations (Dec. 10 th, 1999, Averaged over the target area) NO 2 SPM Reduction of concentration is smaller than emission. Why?

23. 23 Predicted Concentration of PM Components (Dec. 10 th, 1999, Averaged over the target area) SO 4 2- NO 3 - NH 4 + ECOCOther PM 2.5 SPM-PM 2.5 Secondary components Changes in vehicle emissions influence on primary components. Secondary components are affected by transboundary transport.

24. 24 NOx Emission and Pollutant Concentrations NOxNO 2 O3O3 NO 2 is partly limited by O 3 within the metropolitan area. O 3 may increase when NOx emissions are reduced. O 3, and NO 2 are affected by transboundary transport.

25. 25 Summary Following future directions toward improving air quality in Tokyo metropolitan area were implied ; Additional regulations on new vehicles may not be effective. High-emitters running in the real-world should be eliminated. Reduction of NOx emissions may cause increase of O 3. Overall strategies including NMVOC are necessary. Most of SPM emission would be consisted of road dust and sources except for vehicles. Strategies on the transboundary transport are necessary from the viewpoint of urban NO 2 as well as O 3 and PM. Developed JCAP II system is feasible for various analyses.

26. 26 Acknowledgement This study was done in Japan Clean Air Program (JCAP) II. JCAP II was conducted by Japan Petroleum Energy Center and supported by the Ministry of Economy, Trade and Industry, Japan.