1. © Crown copyright Met Office Impact of Emission Schemes on Online Air Quality Modelling WWOSC – Montreal – August 2014 Carlos Ordóñez, Mohit Dalvi, Nick Savage, Paul Agnew, Lucy Davis, Marie Tilbee

2. © Crown copyright Met Office Impact of Emission Schemes on Online Air Quality Modelling 1.Introduction of AQUM 2.Representation of emissions in AQUM 3.Vertical and temporal profiles of emissions 4.Results 5.Summary and outlook

3. © Crown copyright Met Office 1. Introduction

4. © Crown copyright Met Office Air Quality in the Unified Model (AQUM) Limited area configuration of the Unified Model (UM) used for AQ forecast 12 km horizontal resolution & 38 model levels (surface-39km) On-line model: chemistry & aerosol processes fully coupled to meteorology 5-day operational AQ forecast for the UK with: Meteorological LBCs from UM global run Chemical LBCs from MACC global forecast Also run in hindcast mode (chemical LBCs from MACC & GEMS reanalyses, …)

5. © Crown copyright Met Office Chemistry processes represented within the United Kingdom Chemistry and Aerosols (UKCA) sub-model of the UM. UKCA initially developed for climate-chemistry studies at the global scale. A number of chemistry schemes available. Regional Air Quality (RAQ) chemistry scheme implemented to introduce more complex reactive organic chemistry: oxidation of C4 alkanes (butane), C2-C3 alkenes (ethene and propene), and aromatic compounds (toluene and o-xylene) Main features of RAQ Adapted from STOCHEM [Collins et al., 1997, 1999] 40 transported species (16 emitted) + 18 non-advected 116 gas-phase reactions + 23 photolysis reactions Dry deposition for 16 species + wet dep. for 19 species Chemistry and aerosol processes (I)

6. © Crown copyright Met Office CLASSIC aerosol scheme (another UM sub-model, not part of UKCA) SO 2 & ammonium sulphate Ammonium nitrate Black carbon Fossil fuel organic carbon (FFOC) Biomass burning aerosol Climatology of biogenic secondary organic aerosols (BSOA) Online emissions of dust & sea-salt  Calculation of PM 2.5 & PM 10 concs More details or RAQ chemistry and aerosol processes in AQUM: Savage et al. [GMD, 2013] Chemistry and aerosol processes (II) Coupled to UKCA oxidants Future: Use of GLOMAP-mode aerosol scheme. Full coupling between chemistry & aerosols in UKCA Details on CLASSIC & GLOMAP-mode: Bellouin et al. [JGR, 2011; ACP, 2013]

7. © Crown copyright Met Office 2. Representation of emissions in AQUM

8. © Crown copyright Met Office Generation of emissions NAEI @ 1kmENTEC shipping @ 5kmEMEP @ 50km (more recently 5 km MACC dataset, valid for 2003-2009) Generated by merging all source sectors from datasets at different resolution: NAEI, EMEP/MACC & ENTEC

9. © Crown copyright Met Office Generation of emissions NAEI @ 1kmENTEC shipping @ 5kmEMEP @ 50km (more recently 5 km MACC dataset, valid for 2003-2009) Generated by merging all source sectors from datasets at different resolution: NAEI, EMEP/MACC & ENTEC

10. © Crown copyright Met Office Aerosol emissions (in CLASSIC) Combination of monthly 2-D (low-level and high-level) and 3-D fields Online emissions of dust and sea-salt See details in Savage et al. [GMD, 2013] Emissions of gas phase species (in UKCA) Monthly varying emission files: 2-D “surface” emissions of NO x, CO & 14 VOCs (inc. biog C 5 H 8 ) 3-D field for NO x from aircraft All anthropogenic source sectors merged Simplistic vertical profiles and temporal emission factors Current treatment of emission in AQUM UKCA and CLASSIC initially developed for climate-chemistry-aerosol studies at the global scale. The representation of emissions lacks the flexibility needed for regional AQ modelling.

11. © Crown copyright Met Office New emission system for gas phase emissions in UKCA: Independent monthly emission fields for each source sector They can be injected at different altitudes and with different temporal variability Aerosol emissions remain unchanged because CLASSIC will be retired. Future: extend the new system to aerosol emissions in UKCA. New emission scheme

12. © Crown copyright Met Office 3. Vertical and temporal profiles of emissions

13. © Crown copyright Met Office Three types of vertical profiles tested for antropogenic emissions: step1 (current system): Emissions injected in three lowest model levels: 80% (20 m mid-layer), 15% (80 m) & 5% (180 m) EMEP: Profiles based on those from EMEP model [Simpson et al., ACP, 2012] Bieser: Based on calculations with SMOKE-EU plume-rise model [Bieser et al., Env. Pollut., 2011] Vertical disaggregation of emissions Vertical disaggregation for SNAP sectors 1–10 Injection heights: EMEP > Bieser > step1

14. © Crown copyright Met Office traffic-UK (current system): Factors based on traffic UK data applied to all anthropogenic emissions TNO-MACC: Derived by TNO for the MACC project [Denier van der Gon et al., 2011] Temporal emission factors Hourly factors traffic-UK non-traffic Hourly & daily factors needed to account for daily and weekly variability in emissions. Implemented using two sources:

15. © Crown copyright Met Office traffic-UK (current system): Factors based on traffic UK data applied to all anthropogenic emissions TNO-MACC: Derived by TNO for the MACC project [Denier van der Gon et al., 2011] Temporal emission factors Hourly & daily factors needed to account for daily and weekly variability in emissions. Implemented using two sources: traffic-UK traffic (TNO-MACC) non-traffic (TNO-MACC) Daily factors

16. © Crown copyright Met Office 4. Results

17. © Crown copyright Met Office Summary of emission profiles tested Vertical profiles EMEP, Bieser & step1 (EMEP & Bieser evaluated by Mailler et al. [ACP, 2013]) Temporal factors traffic-UK:unreasonable bimodal diurnal cycle TNO-MACC:more realistic

18. © Crown copyright Met Office Summary of emission profiles tested SimulationVertical profilesTime profiles CTRLstep1traffic-UK Bieser-TNOBieserTNO-MACC EMEP-TNOEMEPTNO-MACC We show results (mainly summer 2006/2013) for: operational Comparison with AURN surface observations (> 50 sites) effective emission height Vertical profiles EMEP, Bieser & step1 (EMEP & Bieser evaluated by Mailler et al. [ACP, 2013]) Temporal factors traffic-UK:unreasonable bimodal diurnal cycle TNO-MACC:more realistic

19. © Crown copyright Met Office NO x & O 3 (June – July 2006) SimulationVertical profilesTime profiles CTRLstep1traffic-UK Bieser-TNOBieserTNO-MACC EMEP-TNOEMEPTNO-MACC LBCs from GEMS reanalysis

20. © Crown copyright Met Office NO x & O 3 (June – July 2006) SimulationVertical profilesTime profiles CTRLstep1traffic-UK Bieser-TNOBieserTNO-MACC EMEP-TNOEMEPTNO-MACC LBCs from GEMS reanalysis

21. © Crown copyright Met Office NO x & O 3 (June – July 2006) SimulationVertical profilesTime profiles CTRLstep1traffic-UK Bieser-TNOBieserTNO-MACC EMEP-TNOEMEPTNO-MACC LBCs from GEMS reanalysis

22. © Crown copyright Met Office NO x & O 3 (June – July 2006) SimulationVertical profilesTime profiles CTRLstep1traffic-UK Bieser-TNOBieserTNO-MACC EMEP-TNOEMEPTNO-MACC LBCs from GEMS reanalysis

23. © Crown copyright Met Office SimulationVertical profilesTime profiles CTRLstep1traffic-UK Bieser-TNOBieserTNO-MACC EMEP-TNOEMEPTNO-MACC LBCs from GEMS reanalysis NO x & O 3 (June – July 2006) AURN observations (> 50 sites)

24. © Crown copyright Met Office SimulationVertical profilesTime profiles CTRLstep1traffic-UK Bieser-TNOBieserTNO-MACC EMEP-TNOEMEPTNO-MACC CTRLBieser-TNOEMEP-TNO LBCs from GEMS reanalysis O 3 (June – July 2006) FGE 0.35 0.33 0.32 MNMB -0.03 -0.03 0.01 R 0.70 0.73 0.73 Stdev ratio 0.91 0.93 0.92 fac2 0.86 0.88 0.89

25. © Crown copyright Met Office O 3 (operational: Jul – Aug 2013) CTRLBieser-TNOEMEP-TNO LBCs from MACC global forecast MNMB 0.19 0.20 0.22 R 0.65 0.67 0.67 Stdev ratio 0.97 0.98 0.98 fac2 0.86 0.87 0.87 FGE 0.36 0.35 0.36

26. © Crown copyright Met Office CTRL Bieser-TNOEMEP-TNO Diurnal cycles of bias/RMSE (Jun–Jul 2006) 0 6 12 18 23 NO 2 NO Bias (µg m -3 ) 0 6 12 18 23 RMSE (µg m -3 ) 0 6 12 18 23 O3O3

27. © Crown copyright Met Office Weekly cycles of RMSE (µg m -3 ) NO 2 NOO3O3 CTRL Bieser-TNOEMEP-TNO JJ 2006 Mon Tue Wed Thu Fri Sat Sun JA 2013 Mon Tue Wed Thu Fri Sat Sun

28. © Crown copyright Met Office Minor impact on PM SimulationVertical profilesTime profiles CTRLstep1traffic-UK Bieser-TNOBieserTNO-MACC EMEP-TNOEMEPTNO-MACC

29. © Crown copyright Met Office 5. Summary and outlook

30. © Crown copyright Met Office Summary and outlook (I) A new emission scheme (initially only for gas phase species) implemented Flexibility: Can handle emissions independently according to source sector Allows the use of realistic vertical and temporal profiles Bieser vertical profiles and TNO-MACC temporal factors adopted for operational implementation in AQUM However minor impact on model results for NO x and O 3 Other processes in the model (e.g. chemical LBCs, dry deposition, chemistry) may have a stronger impact on O 3

31. © Crown copyright Met Office Summary and outlook (II) CLASSIC aerosols  GLOMAP-mode aerosols (UKCA). Extend new emission system for aerosols Interactive emission fluxes of biogenic VOCs from JULES (land surface model) in UKCA  Impact on isoprene and O 3 Development of an AQUM configuration at 4 km x 4 km (70L)  Test vertical emission profiles

32. © Crown copyright Met Office

33. Three types of vertical profiles tested for antropogenic emissions: Step1 (current system): Emissions injected in three lowest model levels: 80% (20 m mid-layer), 15% (80 m) & 5% (180 m) EMEP: Profiles based on those from EMEP model [Simpson et al., ACP, 2012] Bieser: Based on calculations with SMOKE-EU plume-rise model [Bieser et al., Env. Pollut., 2011] Vertical disaggregation of emissions Vertical disaggregation for SNAP sectors 1–10 Weighted avg. for NO x, CO and NMVOCs Injection heights: EMEP > Bieser > step1

34. © Crown copyright Met Office

35. Operationally: LBCs from MACC global forecast at ECMWF [Schere et al., AE, 2012] CHIMERE Observations Hindcast: LBCs from MACC & GEMS reanalyses [Savage et al., GMD, 2013]