1. SO 2 Inventory and Direct Radiative Forcing of Sulfate Aerosols over China October 1~2, 2012. Paris. Team: Tao Shu, Li Bengang, Cui siyu Speaker: Li Bengang College of Urban and Environmental Sciences, Peking University SOS in China

2. Contents E MISSION Emission Sources Emission Activities Emission Factors S ULFATE AEROSOLS CTM Model - CanMETOP Processes and Reactions Validation R ADIATIVE FORCING Models – OPAC & SBDART Sensitivity analysis Statistics C ONCLUSIONS Emission Radiative Forcing

3. E MISSION Sources 4 sectors and 15 individual sources were concluded. Coal (4) Power plants / Industrial boiler / Household / Centralized heating Gas (2) Industrial / Residential Oil (4) Power plants / Industrial / Motor vehicle diesel / Motor vehicle gasoline Biomass Burning (5) Residential ( Crop residues / Firewood ) Open fire ( Grass / Forest / Agriculture waste)

4. E MISSION Activities Emission activities data were either collected from official yearbooks or estimated using literature methods. Agriculture waste burning Cao, G. L.; Zhang, X. Y.; Zheng, F. C. Inventory of black carbon and organic carbon emissions from China. Atmos. Environ. 2006, 40 (34), 6516–6527. Grass / Forest fires Yuan, H. S.; Tao, S.; Li, B. G.; Lang, Coveney, R. M. Emission and outflow of polycyclic aromatic hydrocarbons from wildfires in China. Atmos. Environ. 2008, 42 (28), 6828–6835. Energy Consumptions China Energy Statistics Yearbook (1990 ~ 2007). Energy consumption database by Prof. Tao’s group.

5. E MISSION Factors Log-normal distribution of reported EFs was confirmed. Oil Gas Biomass burning Household coal N = 27 N = 12,19,18, 14 N = 15,18 N = 23, 17, 24

6. E MISSION Factors (coal) More detailed estimation was conducted for coal combustion. Centralized Heating Power Plants Industrial Boilers S i is the sulfur content of coal used in province i; S r is the sulfur retention in ash; R i is the removal rate of emission control measures in province i.

7. E MISSION S% Content A coal transportation matrix was used to estimate S% of coal consumed in provinces of China. Province 12345 … … SrSc Beijing 0.8%0.0%8.0%58.1%33.2% …… 0.54%1.03% Tianjin 3.9%0.0%12.8%54.4%28.8% …… 0.0%1.01% Hebei 0.8%0.0%32.2%48.0%18.7% …… 0.87%1.00% Shanxi 0.0% 100.0%0.0% … … 1.16% Inner Mongolia 0.0% 0.6%6.1%93.2% …… 0.87%0.88% … ………………………

8. E MISSION S% Retention Sulfur retention in ash (Sr) was estimated for coal combustion in power plants and industrial boilers. Power Plants Centralized Heating & Industrial Boilers Sulfur content (%) Emission factor (kg/t) N = 9 R2 = 0.88 P < 0.0001 Sr = 13.95% N = 17 R2 = 0.96 P < 0.0001 Sr = 17.42%

9. E MISSION Removal rate Flue gas desulfurization rate ( Removal Rate) in power plants and industrial coal combustion. Power Plants Centralized Heating & Industrial Boilers Province Removal Rate (%) Province Removal Rate (%)

10. E MISSION Factors Geometric means from reported EFs were used. SectorSourceEmission Factor (g.kg -1 ) ResidentialHousehold coal (urban and rural)1.98 Coal consumed in centralized heating10.7* Crop residues burning0.35 Firewood burning0.09 Liquid petroleum gas/natural gas (LPG/NG)0.15 IndustrialBoiler coal combustion10.7* Oil combustion3.78 Gas combustion0.15 Power PlantsCoal combustion10.9* Oil combustion11.10 TransportationMotor vehicle diesel consumption2.50 Motor vehicle gasoline consumption5.83 Open biomassAgriculture waste burning in the field0.22 Forest fire0.99 Grass fire0.35 * national average

11. E MISSION Results(2007) ProvinceRE a INPOTRBBTotal Beijing43.673.978.916.70.0213.2 Tianjin68.386.3182.411.00.0348.0 Hebei126.1658.2802.835.42.91625.4 Shanxi83.1417.4915.418.91.01435.7 Nei Mongol132.1243.5889.845.32.01312.7 Liaoning250.1374.8611.754.61.51292.7 Jilin89.8225.8240.517.13.1576.3 Heilongjiang74.4105.3222.144.46.7452.9 Shanghai43.4126.8333.517.90.0521.7 Jiangsu107.6395.1855.548.92.51409.6 Zhejiang177.1325.8672.159.20.51234.7 Anhui47.2451.0461.220.52.0981.9 Fujian21.6230.4229.429.70.7511.8 Jiangxi29.6216.3331.922.40.8601.0 Shandong419.71013.81254.5104.45.32797.7 Henan109.0834.0882.233.94.11863.2 Hubei55.7554.7579.749.71.31241.2 Hunan62.7640.2331.932.91.21068.8 Guangdong35.1412.9871.891.61.21412.5 Guangxi38.3377.1258.532.31.3707.4 Hainan0.69.440.25.20.255.6 Chongqing29.9238.2227.018.00.5513.6 Sichuan51.6485.1536.736.71.71111.8 Guizhou70.9455.0844.115.20.61385.7 Yunnan21.3170.5319.631.614.6557.5 Xizang0.90.10.04.90.15.9 Shannxi52.8341.3538.625.80.9959.4 Gansu44.590.6182.010.00.3327.5 Qinghai3.947.257.03.40.0111.5 Ningxia12.577.5218.36.50.1314.9 Xijiang100.0192.9234.925.10.6553.5 Taiwan0.0176.9355.7124.20.0656.8 Hong Kong0.039.280.635.90.0155.7 Macao0.0 1.00.01.0 Total2403.710087.114640.71130.157.528319.1 a RE = Residential, IN = Industrial, PO = Power Plant, TR = Transportation, BB = Open Biomass Burning Uint: Gg.yr -1

12. E MISSION Results(2007) Uint: kg.km -2.yr -1 County level SO 2 emission of China in 2007

13. E MISSION Results(2007) Uint: Gg.yr -1 Grid map of SO 2 emission in China (2007) Grid size: 24 km  24 km

14. E MISSION Statistics Coal consumption in power plants and industrial boilers emits most SO 2 in China (2007).

15. E MISSION Comparison Sectors contribution differs from other countries. PO: China (51.0%), USA (81.5%), Europe (64.0%) IN: China (37.8%), USA (14.2%), Europe (27.1%) RE: China (8.1%) may be due to centralized heating

16. E MISSION Comparison Comparison of SO 2 emission inventory at the national level 1990: 15.3 Tg 2005: 30.5 Tg 2007: 28.3 Tg

17. E MISSION Time trends Comparison of SO 2 emission inventory at the national level PO IN TR

18. E MISSION Time trends Emission factor was decreasing due to increasing removal rate. However, emission almost doubled from 1990 to 2007. Emission factor (kg/t) Removal Rate (%) Emission ( Tg ) In the future?

19. Sulfate Model CanMETOP （ Canadian Model for Environmental Transport of Organochlorine Pesticides ） A Coupled Atmospheric Transport, Soil-Air, and Water-Air Exchange Model (Ma et al., ES&T, 2003), 12 vertical layers, 20 min time step Three-dimensional regional scale dispersion model, Gas-phase reactions, Aqueous-phase oxidation, Dry / Wet deposition Meteorologic data (wind, T, precipitation) OH radical number concentrations (GEOS-Chem archive) Emission grid (210  270 grids, 24 km  24 km) Model Reactions & Processes Supporting Data

20. Sulfate Model Result Column concentration of SO 2 over China, (mg.m -2 )

21. Column concentration of SO 4 -2 over China, (mg.m -2 ) Sulfate Model Result

22. Sulfate Validation EANET monitoring data was used for validation. Acid Deposition Monitoring Network in East Asia (EANET) Data Report 2007

23. Sulfate Validation Overall good agreement was found for 27 EANET points. Modeled & Observed Annual Average of SO 2 Ground Concentration in Lg (  g.m -3 )

24. Cheju Hedo

25. Sulfate Validation Overall good agreement was found for 2 island points. Observed Modeled Ground Concentration,  g.m -3 Month SO 2 Ground Concentration

26. Rad. Forcing Model Model OPAC and SBDART were used. OPAC - Optical Properties of Aerosols and Clouds Hess M., Koepke P. et al, 1998, Bulletin of the American Meteorological Society, 79(5): 831-844. Extinction coefficient (  e ) Asymmetry parameter (g) Single scattering albedo (  ) Optical depth (  ) SBDART - Santa Barbara DISORT Atmospheric Radiative Transfer Ricchiazzi P., Yang S. et al. 1998, Bulletin of the American Meteorological Society 79(10): 2101-2114. Fatima H., Upadhyaya H. et al. 2011, Meteorology and Atmospheric Physics 112(3-4): 101-115.

27. Rad. Forcing Model Key parameters of OPAC and SBDART Relative humidity - Monthly RH data in 198 sites (http://cdc.cma.gov.cn/index.jsp) Sensitivity – Optical depth (  ) > Single scattering albedo (  ) > Surface reflectance (Rs) > Asymmetry parameter (g) Surface reflectance – MODIS BRDF/Albedo V005 product MCD43C3 data (0.05 o ) - http://ladsweb.nascom.nasa.gov/data/search.html

28. Rad. Forcing Results Direct radiative forcing of sulfate aerosols over China, (2007, annual average, w.m -2 )

30. ChinaReference springsummerautumnwinterannualaverageminimummaximum 7.7713.339.084.698.722.481.195.50 0.03490.06060.04090.02130.03940.0210.0060.042 -1.220-2.067-1.383-0.817-1.372-0.405-0.160-0.960 -157-155-152-174-157-169-72-293 -35-34 -38-35-19-8-32 Rad. Forcing Comparison Normalised RF by mass and normalised RF per unit τ aer

31. Rad. Forcing Statistics Statistics of DRF of sulfate aerosols for seven sub- regions. (2007, w.m -2 ) springsummerautumnwinterannual North China -0.846-3.716-1.841-0.410-1.703 Northeast China -1.584-2.928-1.753-0.409-1.669 East China-5.393-6.812-4.070-3.792-5.017 Central China -3.509-5.010-3.749-3.155-3.856 South China -1.548-1.505-2.278-0.773-1.526 Southwest China -0.603-0.859-0.581-0.470-0.628 Northwest China -0.141-0.307-0.329-0.102-0.220 Total China-1.220-2.067-1.383-0.817-1.372

32. Rad. Forcing Surface reflectance Direct radiative forcing of sulfate aerosols over China, (2007, annual average, w.m -2 ) Radiative forcing, W.m -2 Surface reflectance Latitude

33. Rad. Forcing Surface reflectance Positive radiative forcing occurs where surface reflectance is high in winter months.

34. Conclusions SO 2 emission reaches 28.3 Tg in 2007. Coal combustion contributes more than 90%. Emission factor is decreasing due to increasing removal rate. However, emission almost doubled from 1990 to 2007. In average, both sulfate aerosols loading and related radiative forcing in China are higher than other places in the world. Especially in east part of China. In some snow covered areas, positive radiative forcing occurs due to high surface reflectance in winter months. EMISSION REDIATIVE FORCING

35. Acknowledgement Thanks to scientists from France. Thanks to professor PIAO. Thanks to professor TAO and team mates. Questions?