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Explore the results and discussion on air quality in Asia using the OsloCTM2 model in 1°×1° resolution. Focus areas include black carbon, ammonia, nitrates, sulphates, sea salt, mineral dust, and gases.
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New results from the OsloCTM2 model run in 1°×1° resolutionTore Flatlandsmo Berglen, Gunnar Myhre, Ivar S.A. Isaksen, Terje K. Berntsen & Nguyen Thi Kim Oanh Tore Flatlandsmo Berglen ASAAQ 16. May 2007
Outline ● OsloCTM2 model description ● Overview of chemical modules ● Results and discussion; a focus on Asia => BC, NH4+, NO3- , SO42- , sea salt, mineral dust, gases ● Summary and conclusion Tore Flatlandsmo Berglen ASAAQ 16. May 2007
1°×1° is a very fine resolution for a global model, we approach a spatial scale previously known from regional models. Advantage: avoid noise from boundary conditions. May perform regional AND global studies using the same model runs. OsloCTM2 has the most important gases and aerosol processes included. May study both air quality AND climate issues. What is the main improvement?? Tore Flatlandsmo Berglen ASAAQ 16. May 2007
OsloCTM2 model description ● Global Chemical Transport Model ●T21 (5,6°×5,6°) to 1°×1° horizontal resolution ● 19, 40 or 60 layers (σ-coordinates) ● Meteorological data from IFS model at ECMWF (“real weather”), updated every 3 hours. Consistent data. ● Transport; Second Order Moments ● Boundary layer mixing; Holtslag et al. (1990) ● Meteorological data for 2004 Tore Flatlandsmo Berglen ASAAQ 16. May 2007
Overview of chemical modules ● Tropospheric chemistry [● Stratospheric chemistry] ● Sulphur chemistry ● Sea salt ● Nitrate ● Mineral dust ● Organic Carbon / Black Carbon [● Secondary Organic Aerosols (in progress)] Tore Flatlandsmo Berglen ASAAQ 16. May 2007
Results and discussion; a focus on Asia ● Air quality ● Surface concentrations ● BC, sea salt, nitrate components, sulphate, mineral dust, ozone ● Instant plots, not averages. Tore Flatlandsmo Berglen ASAAQ 16. May 2007
Results and discussion, cont’d ● OC / BC: - Emissions from; Bond et al., JGR (2004) GFED data base for biomass burning - Lifetime for hydrophobic carbon ~ 4 days (Maria et al., Science, 2004) Tore Flatlandsmo Berglen ASAAQ 16. May 2007
Results and discussion, cont’d ● BC: 31. January 9 a.m & 9 p.m. GMT; afternoon and late night SE Asia Tore Flatlandsmo Berglen ASAAQ 16. May 2007
Comparison with observations Results and discussions, cont’d Tore Flatlandsmo Berglen ASAAQ 16. May 2007
Results and discussion cont’d ● Sea Salt: - Described in Grini et al., J. Climate (2002) - Wind driven emissions. - Important for nitrate, react with HNO3 in coarse mode Tore Flatlandsmo Berglen ASAAQ 16. May 2007
Results and discussion, cont’d ● Sea Salt: 31. January 9 a.m & 9 p.m. GMT; afternoon and late night SE Asia Tore Flatlandsmo Berglen ASAAQ 16. May 2007
Comparison with observations Results and discussions, cont’d Tore Flatlandsmo Berglen ASAAQ 16. May 2007
Results and discussion cont’d • ● Ammonium NH4+ & nitrate NO3- : • - EQSAM module, thermodynamic package by Metzger et al., JGR (2002) • Fine mode and coarse mode particles • Ammonium first neutralize sulphuric acid ((NH4)2SO4) • If more ammonia available, ammonium nitrate can form (NH4NO3) • - Then sea salt may react with HNO3 (coarse mode) Tore Flatlandsmo Berglen ASAAQ 16. May 2007
Results and discussion, cont’d ● Ammonium NH4+: 31. July 9 a.m & 9 p.m. GMT; afternoon and late night SE Asia Tore Flatlandsmo Berglen ASAAQ 16. May 2007
● Nitrate NO3-: Results and discussion, cont’d 31. July 9 a.m & 9 p.m. GMT; afternoon and late night SE Asia Tore Flatlandsmo Berglen ASAAQ 16. May 2007
Comparison with observations Results and discussions, cont’d Tore Flatlandsmo Berglen ASAAQ 16. May 2007
Results and discussion cont’d • ● Sulphate SO42-: • Sulphur module from Berglen et al., JGR, (2004) • - DMS, SO2, sulphate, H2S & MSA • Sulphur calculated on-line with tropospheric oxidants; • SO2 is oxidized by OH in gas phase, O3, H2O2, HO2NO2 & metals in aqueous phase. Tore Flatlandsmo Berglen ASAAQ 16. May 2007
Results and discussion, cont’d ● Sulphate SO42-: 31. July 9 a.m & 9 p.m. GMT; afternoon and late night SE Asia Tore Flatlandsmo Berglen ASAAQ 16. May 2007
Comparison with observations Results and discussions, cont’d Tore Flatlandsmo Berglen ASAAQ 16. May 2007
Results and discussion, cont’d ● Mineral dust: 31. July 9 a.m & 9 p.m. GMT; afternoon and late night SE Asia Tore Flatlandsmo Berglen ASAAQ 16. May 2007
● AOD results Results and discussion, cont’d Tore Flatlandsmo Berglen ASAAQ 16. May 2007
Results and discussion, cont’d ● Tropospheric chemistry: Ozone 31. July 9 a.m & 9 p.m. GMT; afternoon and late night SE Asia Tore Flatlandsmo Berglen ASAAQ 16. May 2007
Summary and Conclusion ● OsloCTM2 in 1°×1° resolution is a fine scale for a global model ● Captures regional phenomena ● Represents well diurnal variation (chemistry and transport) ● Detailed meteorology ● Detailed gas and aerosol schemes. ● Some discrepancies exist, still work to be done (as always) ● Contact: t.f.berglen@geo.uio.no Tore Flatlandsmo Berglen ASAAQ 16. May 2007
Sulphur in OsloCTM2 Tore Flatlandsmo Berglen ASAAQ 16. May 2007
Results and discussion, cont’d ● Tropospheric chemistry: CO 31. July 9 a.m & 9 p.m. GMT; afternoon and late night SE Asia Tore Flatlandsmo Berglen ASAAQ 16. May 2007