1 / 28

GMI aerosol GMI – AeroCom activities

GMI aerosol GMI – AeroCom activities . August 4, 2011. Huisheng Bian, Mian Chin, Steve Steenrod , Hongbin Yu, Jose Rodriguez, Sarah Strode, Duncan Fairlie , and Bryan Duncan . Aerocom A2. GMI participated in the Aerocom A2 activities:

jed
Download Presentation

GMI aerosol GMI – AeroCom activities

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. GMI aerosolGMI – AeroCom activities August 4, 2011 Huisheng Bian, Mian Chin, Steve Steenrod, Hongbin Yu, Jose Rodriguez, Sarah Strode, Duncan Fairlie, and Bryan Duncan

  2. Aerocom A2 • GMI participated in the Aerocom A2 activities: 1. direct aerosol forcing 2. surface aerosol efficiency experiment 3. dust and BC depositions in the Arctic 4. organic aerosol • To participate these activities, GMI did: 1. implement gas and aerosol coupling model 2. implement a module for nitrate and ammonium mass simulation 3. upgrade the AOD and forcing codes to include new components of nitrate/ammonium

  3. Aerocom direct aerosol forcing experiment • Organizers Gunnar Myhre, Michael Schulz, Philip Stier, and Stefan Kinne • CMIP5 emission 2000 for present and 1850 for preindustrial • Met fields 2006 for both present and preindustrial • Phase 1 (previous) : SO4, BC, OC Phase 2 (current) : adds NO3 and SOA • 9 models have submitted their results • Bjorn Samset and Gunnar Myhre did multimodel comparison and present the results at http://folk.uio.no/bjornhs/cicero/aerocom/A2/gallery/

  4. Aerocom A2: direct aerosol forcing Aerosol radiative forcing all sky [W/m2] all SO4 NO3 BCFF OCFF BB

  5. Aerocom A2: direct aerosol forcing Aerosol radiative forcing clear sky [W/m2] all SO4 NO3 BCFF OCFF BB GMI has the largest ratio of aerosol radiativeforcings between all sky and clear sky

  6. Aerocom A2: direct aerosol forcing GEOS4 cloud field is an outlier Cloud fraction Original data or application in radiative code? Mainly due to the cloud Top albedo Surface albedo

  7. Aerocom A2: direct aerosol forcing Optical Depth at 550 nm 2006 all 1850 all 2006 ant frac 2006 ant

  8. Aerocom A2: direct aerosol forcing Optical Depth at 550 nm SO4 NO3 OCFF BCFF BB

  9. Aerocom A2: direct aerosol forcing Aerosol absorption at 550 nm 2006 all 1850 all 2006 ant frac 2006 ant

  10. Aerocom A2: direct aerosol forcing Single scattering albedo 2006 all 1850 all 2006 ant

  11. Aerocom A2: direct aerosol forcing Aerosol zonal mean burden [mg/m2] SO4 NO3 OCFF BCFF BB

  12. Summary - 1 • The nitrate and ammonium aerosols can be simulated by a newly developed coupling GMI model. • The GMI performance for aerosol mass, AOD, and forcing including nitrate and ammonium aerosols has been reviewed in AeroCom A2 activity. • The absorption of GMI is relatively weak. Otherwise, GMI has reasonable results. • The cloud fraction of GEOS4 is much lower among the models so GMI has the lowest top albedo and largest ratio between all sky aerosol forcing and clear sky aerosol forcing by using GEOS4.

  13. Nitrate simulation and Chemical response to nitrate aerosol

  14. Impact of nitrate aerosol Compare CoupleNO3 with CastNet observation (36.5N, 116.8W) (39.0N, 107.0W) (41.8N, 72.0W) (27.8N, 80.5W) SO4 [μg/m3] NO3 [μg/m3] NH4 [μg/m3] HNO3 [μg/m3]

  15. Impact of nitrate aerosol Overall comparison with CastNet HNO3 SO2 SO4 NO3a NH4a

  16. Impact of nitrate aerosol Compare CoupleNO3 with EMEP observation (40.3N, 33.0E) (62.5N, 8.5E) (54.6N, 8.2E) (42.6N, 12.3E) SO4 [μg/m3] NO3 [μg/m3] NH4 [μg/m3] HNO3 [μg/m3]

  17. Impact of nitrate aerosol Overall comparison with EMEP HNO3 SO2 SO4 NO3a NH4a

  18. Impact of nitrate aerosol January 2006 Relative change : (CoupleNO3 – Couple) / Couple HNO3 O3 NOx H2O2 % % % % mixing ratio distributions ppb ppb ppb ppt OH 1.e5 #/cm3 % ppb

  19. Impact of nitrate aerosol July 2006 Relative change : (CoupleNO3 – Couple) / Couple O3 HNO3 NOx H2O2 % % % % mixing ratio distributions % ppb ppb ppb ppt OH 1.e5 #/cm3 %

  20. Summary -2 • The GMI HNO3 is generally much higher than observation. • Nitrate simulation has little impact on sulfate simulation. • With nitrate included, the surface concentrations of key gas tracers, i.e. HNO3, NOx, O3, H2O2, and OH, generally decreased globally in January. The tracers also decreased in July except O3 over tropical oceans and NOx over Antarctic.

  21. Chemical response to coupling model

  22. Impact of coupling model January 2006 Relative change : (Couple – Combo) / Combo NOx HNO3 O3 H2O2 % % % % mixing ratio distributions % ppb ppb ppb ppt OH 1.e5 #/cm3 % ppb

  23. Impact of coupling model July 2006 Relative change : (Couple – Combo) / Combo HNO3 NOx O3 H2O2 % % % % mixing ratio distributions ppb ppb ppb ppt OH 1.e5 #/cm3 %

  24. Summary • With and without gas-aerosol coupling, the change of chemical fields are non-negligible over regional scales. • The response of chemical fields to the coupling approach is larger in January than in July.

  25. Impact of nitrate aerosol Overall comparison with EMEP HNO3 SO2 SO4 NO3a NH4a

  26. Impact of coupling model January 2006 Absolute change : (Couple – Combo) NOx HNO3 O3 H2O2 ppb ppt ppb ppt mixing ratio distributions % ppb ppb ppb ppt OH 1.e5 #/cm3 1.e5 #/cm3 ppb

  27. Impact of coupling model July 2006 Absolute change : (Couple – Combo) HNO3 NOx O3 H2O2 ppb ppt ppb ppt mixing ratio distributions ppb ppb ppb ppt OH 1.e5 #/cm3 1.e5 #/cm3

  28. Summary -2 • The GMI HNO3 is generally much higher than observation. • The underestimation of HNO3 over the polluted European region implies that it may be necessary to introduce alkalinity of dust and sea salt to restrict heterogeneous reaction of HNO3 on these aerosols. • Nitrate simulation has little impact on sulfate simulation. • With nitrate included, key gas tracers, i.e. HNO3, NOx, O3, H2O2, and OH, generally decreased globally in January. The tracers also decreased in July except O3 over tropical oceans.

More Related