Distribution and sources of submicron aerosols during the WINTER 2015 aircraft campaign

Transcription

1 40 o N 35 o N 30 o N Distribution and sources of submicron aerosols during the WINTER 2015 aircraft campaign Feb. 1 Mar. 15, o W 80 o W 75 o W 70 o W Viral Shah, Lyatt Jaeglé University of Washington, Seattle, WA Most observations below 1 km altitude Altitude km J.C. Schroder, P. Campuzano-Jost, J.L. Jimenez SO 4 2-, NO 3-, NH 4 +, - HR-ToF-AMS J. Green, M.N. Fiddler, S. Bililign SO 2 :UV fluorescence E. McDuffie, D. Fibiger, W.P. Dube, S.S. Brown NO y :TD-CRDS F. D. Lopez-Hilfiker, B.H. Lee, J.A. Thornton HNO 3 :Iodide-CIMS

2 Summer vs. wintertime aerosols over eastern U.S. Chemical Speciation Network surface observations [U.S. EPA] Summer Winter Concentration [μg m -3 ] Other EC NH4 + NO3 - SO μg m μg m -3 22% less biogenic 17% 45% 2005 partial shift from SO 4 2- to NO 3-23% 15% 23% 25% 2005 Other EC 25% NH4 + NO3 - SO4 2-

3 Summer vs. wintertime aerosols over eastern U.S. Chemical Speciation Network surface observations [U.S. EPA] Summer Winter Concentration [μg m -3 ] Other EC NH4 + NO3 - SO μg m -3 6 μg m larger decline during summer 11 μg m -3 9 μg m -3 25% 15% 27% 21% winter concentrations higher than summer EC NH4 + NO3 - SO4 2-

4 Wintertime aerosols over eastern U.S. Chemical Speciation Network surface observations [U.S. EPA] Summer Winter Winter SO4 Concentration [μg m -3 ] Other EC NH4 + NO3 - SO μg m -3 6 μg m Winter 11 μg m -3 9 μg m -3 25% 15% 27% 21% EC NH4 + NO3 - Winter SO4 2- Projected ( ) from emission changes alone [Pye et al., 2009,JGR] Projected decrease in SO4 Projected increase in NO3 NO3 2 μg m -3 NH4 0.5 μg m -3 2 μg m -3

5 GEOS-Chem simulations v10-01; GEOS-FP; one-way nested-grid

6 Simplified chemistry [Hodzic & Jimenez, 2011, GMD, Kim et al., 2015, ACP] +OH GEOS-Chem simulations v10-01; GEOS-FP; one-way nested-grid P Non-volatile τ=3 d +OH VOC S τ=18 hr ISOP: 3% MONO:5% Modifications Anthropogenic & BB emissions Biogenic emissions

7 Simplified chemistry Fe/Mn catalyzed sulfate production + bug fixes GEOS-Chem simulations v10-01; GEOS-FP; one-way nested-grid [Hodzic & Jimenez, 2011, GMD, Kim et al., 2015, ACP] +OH P S Non-volatile τ=3 d +OH VOC Anthropogenic & BB emissions τ=18 hr ISOP: 3% MONO:5% Biogenic emissions Modifications [Alexander et al., 2009; 2012 JGR] Sulfate production (below 2 km) kgs/day v10-01 Revised fold increase in SO 4 production 0

8 GEOS-Chem simulations v10-01; GEOS-FP; one-way nested-grid Modifications Simplified chemistry [Hodzic & Jimenez, 2011, GMD, Kim et al., 2015, ACP] +OH P Non-volatile τ=3 d +OH VOC Anthropogenic & BB emissions S τ=18 hr ISOP: 3% MONO:5% Biogenic emissions Fe/Mn catalyzed sulfate production + bug fixes [Alexander et al., 2009, 2012 JGR] Sulfate production (below 2 km) kgs/day v10-01 Revised 4000 Production & loss of HNO 3 N 2 O 5 heterogeneous reaction [Bertram and Thornton,2009,ACP] Lower resistance to dry dep. [Wesely and Hicks,2000,Atmos Env] Total nitrate (HNO 3 +NO 3- ) Altitude [km] Aircraft observations 2.1 μg m -3 v μg m -3 Revised 2.8 μg m -3 3-fold increase in SO 4 production HNO 3 +NO 3- (μg m -3 )

9 Emissions & lifetimes of SO 2, NO y, NH 3 Emissions: NEI 2011 scaled to 2015 SO 2 NOx NH 3 63 GgS mth GgN mth -1 92% Elec. Gen. 63% Vehicles 27% Elec. Gen. 30 GgN mth -1 67% Livestock 17% Fertilizer τ dep = 1.5 days τ dep = 2 days τ dep = 3 days kgs km -2 mth kgn km -2 mth kgn km -2 mth -1 Altitude [km] SO 2 +SO 4 2- NO y +NO 3 - NH 3 +NH 4 + Obs:1.8 ppbv v10-01:1.4 Observations GEOS-Chem Obs:3.8 ppbv v10-01:3.1 Obs:0.6 ppbv v10-01:1.2 v ppb NH 3 emissions (GgN month 1 ) NEI 2011 NH 3 emissions [Gilliland et al., 2006, Atmos. Env.] Lower emissions when cold J F M A M J J A S O N D SO 2 +SO 4 2- (ppbv) NO y +NO 3 - (ppbv) NH 3 +NH 4+ (ppbv)

10 Emissions & lifetimes of SO 2, NO y, NH 3 Emissions: NEI 2011 scaled to 2015 SO 2 NOx NH 3 63 GgS mth GgN mth -1 92% Elec. Gen. 63% Vehicles 27% Elec. Gen. 10 GgN mth -1 40% Livestock 20% Fertilizer τ dep = 1.5 days τ dep = 2 days τ dep = 3 days kgs km -2 mth kgn km -2 mth kgn km -2 mth -1 Altitude [km] SO 2 +SO 4 2- NO y +NO 3 - NH 3 +NH 4 + Obs:1.8 ppbv v10-01:1.4 Observations GEOS-Chem Obs:3.8 ppbv v10-01:3.1 Obs:0.6 ppbv v10-01:1.2 Revised:0.7 v ppb Revised 0.7 ppb NH 3 emissions (GgN month 1 ) 100 Revised livestock emissions E NH3 ~ *T [Aneja et al., 2000, JGR] NEI2011 Revised 3-fold decrease J F M A M J J A S O N D SO 2 +SO 4 2- (ppbv) NO y +NO 3 - (ppbv) NH 3 +NH 4+ (ppbv)

11 Submicron aerosols during WINTER Sulfate-Nitrate-Ammonium AMS Observations: 2.6 ± 1.5 μg m -3 GEOS-Chem: 2.7 ± 1.9 μg m -3 NMB: 4% Norm. Mean Bias FAC2:81% 0.5<model/obs<2 Composition Observed GEOS-Chem (AMS) NH4 21% NO3 33% 46% SO4 NH4 24% NO3 32% 44% SO µg m -3

12 Submicron aerosols during WINTER Sulfate-Nitrate-Ammonium AMS Observations: 2.6 ± 1.5 μg m -3 GEOS-Chem: 2.7 ± 1.9 μg m -3 NMB: 4% Norm. Mean Bias FAC2:81% 0.5<model/obs<2 Composition Observed GEOS-Chem (AMS) NH4 21% NO3 33% 46% SO4 NH4 24% NO3 32% 44% SO µg m -3 Organic aerosol AMS Observations: 1.6 ± 1.0 μg m -3 GEOS-Chem: 2.5 ± 1.7 μg m -3 NMB:58% FAC2:68% Source composition Observed (AMS-PMF) (first 6 flights) GEOS-Chem S P S P 37% 63% 59% 41% µg m -3

13 Winter aerosol formation pathways Emissions SO2+OH (5%) (19%) SO2+H2O2 (39%) SO2+O3 (16%) SO2+O2 (Fe/Mn) (21%) NO2+OH (g) (44%) N2O5+H2O (het) (55%) VOC+NO3 (1%) HNO3 SO4 NO3 32% 16% NH4 12% 40% NH3 P S Emissions below 2 km Anthropogenic (45%) Anthropogenic (53%) Biogenic (2%)

14 Winter aerosol formation pathways Emissions SO2+OH (5%) (19%) SO2+H2O2 (39%) SO2+O3 (16%) SO2+O2 (Fe/Mn) (21%) NO2+OH (g) (44%) N2O5+H2O (het) (55%) VOC+NO3 (1%) HNO3 SO4 NO3 32% 16% NH4 12% 40% NH3 P S Emissions below 2 km Anthropogenic (45%) Anthropogenic (53%) Biogenic (2%)