Performance of CMAQ for Inorganic Aerosol Compounds in Greater Tokyo Hiroshi HAYAMI Central Research Institute of Electric Power Industry and Tatsuya SAKURAI Tokyo University of Science
Acknowledgements National Institute of Environmental Studies Shinji Kobayashi and Shinji Wakamatsu Japan Clean Air Program of Petroleum Energy Center Tazuko Morikawa Institute of Behavioral Sciences Akiyoshi Kan-nari and Tsuyoshi Baba Fujitsu FIP Corp. Noritaka Furuhashi, Izumi Ikeuchi and Hisashi Tashiro
Aerosol pollution in G.Tokyo PM mass averages SPM* by beta gauge ~ 40 µg m-3 >40 % stations violated the standard in the 1990s PM2.5 by TEOM ~ 25-30 µg m-3 > US std. high in early summer and early winter Composition of SPM carbon(EC/OC) ~ 30 % inorganic species ~ 30 % *SPM: PM with 100% cut at 10 µm ~ PM7
Our studies with CMAQ for G.T. budget of ammonia long-term (one year) episodes of inorganic aerosols 2 to 3 days in summer and winter presented by Sakurai in poster session presented from now
Study Domains for SIA in G.T. D0(East Asia) @45 km D1(C. Japan) @15 km D2(G. Tokyo) @5 km MM5 CMAQ no interaction two-way initial and boundary conditions
Model Options & Configurations MM5 V3.6-1 35 layers; ~25 m in the lowest layer FDDA with JMA’s RANAL (20km, 12hrs.) Grell, MRF, simple ice, multi-layer soil CMAQ 4.2.2 (MCIP 2.1) 16 layers; identical to MM5 in PBL CB4-AE3-AQ solved with MEBI CMAQ dry and RADM-cloud wet dep. ACESS for E.Asia and NIES/JCAP for GT
Emission inventory (NIES/JCAP) SOx [ton day-1] NOx [ton day-1] condensed dust [ton day-1]
CMAQ vs. field campaigns WINTER Dec. 9 to 10, 1999 SUMMER Jul.31 to Aug.1,2001 T,RH,WS,WD Tokyo, Kumagaya, Tateyama NO2, SO2, O3 Fukaya, Yokosuka Tokyo(Komae) Kumagaya NMHC composition Fukaya ― particulate NO3-, NH4+, SO42- gaseous HNO3, NH3
Winter: at Fukaya Gas Aerosol (FP) F Y obs. CMAQ obs. CMAQ NO2 [ppb] NO3- [µg m-3] SO2 [ppb] SO42- [µg m-3] O3 [ppb] NH4+ [µg m-3] Dec. 9 Dec. 10 Dec. 9 Dec. 10
Winter: at Yokosuka Gas Aerosol (FP) F Y obs. CMAQ obs. CMAQ NO2 [ppb] NO3- [µg m-3] SO2 [ppb] SO42- [µg m-3] O3 [ppb] NH4+ [µg m-3] Dec. 9 Dec. 10 Dec. 9 Dec. 10
Winter contour: PM [µg m-3] 18:00 Dec. 9, 1999 18:00 Dec. 10, 1999 observed CMAQ observed CMAQ not good “observed” SPM(~PM7) vs. “calculated” PM2.5 SPM = SIA + EC + OC + Cl- +… PM2.5 in CMAQ
Summer: Gas at Tokyo better than winter K T obs. CMAQ NO2 [ppb] SO2 [ppb] O3 [ppb] better than winter Jul. 31 Aug. 1
Summer: SIA at Tokyo K T NO3- [µg m-3] NH4+[µg m-3] SO42-[µg m-3] obs. CMAQ NO3- [µg m-3] NH4+[µg m-3] SO42-[µg m-3] particulate 12 12 Jul. 31 Aug. 1 gaseous 12 12 12 12 Jul. 31 Aug. 1 Jul. 31 Aug. 1
Summer contour: PM much better than winter 12:00 Jul. 31, 2001 12:00 Aug. 1, 2001 observed CMAQ observed CMAQ much better than winter summer SPM mainly made of SIA
Summary CMAQ is fine to improve the performance… secondary > primary products summer > winter to improve the performance… Cl- and SOA (winter) better boundary concentrations (SO2 & SO42-) alter the gas-aerosol partitioning of NO3- and NH4+
under testing CMAQ with... HCl/Cl-, important in winter aerosol emission, deposition and gas-aerosol reaction coarse aerosol nitrate and chloride gas/coarse aerosol reaction upper boundary free-tropospheric ozone sulfate formation on aerosol surface heterogeneous reaction of SO2
SO2-to-SO42-(p) conversion homogeneous + nucleation SO2 + OH => H2SO4(g) H2SO4(g) => SO42-(p) aqueous chemistry in cloud water SO2 + cw => SO42-(aq) SO42-(aq) => SO42-(p) heterogeneous chemistry SO2 + aerosol surface => SO42-(p)