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An update on AC&C activities Phil Rasch, Martyn Chipperfield, Sarah Doherty, A. R. Ravishankara

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An update on AC&C activities Phil Rasch, Martyn Chipperfield, Sarah Doherty, A. R. Ravishankara. Ravi stepped down, Martyn replaced him Progress report Discussion/Advice on Activities Ancillary Activities. Atmospheric Chemistry and Climate: Timeline. Summer/Fall, 2007 : - PowerPoint PPT Presentation

Text of An update on AC&C activities Phil Rasch, Martyn Chipperfield, Sarah Doherty, A. R. Ravishankara

  • An update on AC&C activitiesPhil Rasch, Martyn Chipperfield, Sarah Doherty, A. R. RavishankaraRavi stepped down, Martyn replaced himProgress reportDiscussion/Advice on ActivitiesAncillary Activities

  • Atmospheric Chemistry and Climate: TimelineSummer/Fall, 2007: AC&C Activity plans developed AC&C liaisons initiate coordination with AeroCom, CCMVal, HTAPMarch 2008: Conference call of AC&C Steering Committee Review/discussion of activity plans (for 3 of 4 activities) Agreement to arrive at workshop with detailed model run plans & example model run outputJune, 2008: 2nd AC&C Workshop, joint w/ HTAP (Washington, D.C.) Finalize activity model runs with engagement of all model groups, in close coordination with HTAP next phase plansThe Path Forward:Mid-2008 2009: Model runs, publicationsLate 2009: Models are frozen for next IPCC Assessment

    Revising the paradigm: (Phils opinion)No longer preparing models to be used for IPCC runs, but.Design, Facilitate, Coordinate some of runs relevant to IPCC,

  • Activity 1: 20 year HindcastPeter Hess, Jennifer Logan, Oliver Wild

    Activity 2: What controls the vertical distribution of species. Step 1: Focus on 5 km -> tropopauseJos Rodriguez, Joyce Penner, Cline Mari, (CCMVal Andrew Gettelman?)

    Activity 3: Cloud-chemical interactionsCurrently on hold & (possibly) being re-defined

    Activity 4: Future Scenarios: Sensitivities & UncertaintiesDrew Shindell, J-F Lamarque, Michael Schulz, (CCMVal Veronika Eyring)AC&C Initiative: Activities for Phase INeeds Resuscitation at a later time

  • Activity 1: Hindcast Experiments

    Needed a coordinator/facilitator (e.g. some funding)Just lined up Contributions from NASA, DOE, NOAA, EPA for a post-doc/research associate for 2 years

    We did not propose a single hindcast experiment from 1980 But, a series of interrelated experiments

    Each hindcast experiment defined by: a multi-year series (post-1980) a clear objective grading criteria for evaluating model success. a set of required diagnostics to facilitate model comparison and evaluation.multi-year external forcings (e.g., emissions) needed to drive the simulations.guidelines on the types of chemical models and meteorological fields that can usefully participate

  • Activity 1: Simple Tracer Hindcast (C. Nevison, M. Prather, N. Mahowald)Goal: Match the trends and variability of the nearly-inert trace gases CFCs and N2O as measured by stations of the ALE/GAGE network. Quantify importance of: -changing emissions-tropospheric meteorology-stratosphere-troposphere exchange variability.From Nevison et al., Interannual Growth Rate Anomalies: Match and AGAGE

  • Activity 1: Aerosol Hindcast(Michael Schulz, Mian Chin)Goals: Better understanding of:-regional and global satellite observed trends in AOD-regional differences in sulfate and black carbon deposition from the Arctic to the Alpes-temporal trends in aerosol concentration, composition, optical properties and deposition-emission trends of primary aerosols and aerosol precursor gazes-the impact of changing meteorology vs changing emissions on aerosol trends-dimming and brightening trends observed by surface radiation networks-the evolution of the anthropogenic aerosols perturbation of the Earth radiative balance

    To be run as part of AEROCOM

    FromRamanathan et al., 2005

    Observed and simulatedSurface RadiationFluxes over India

  • Activity 1: Ozone Hindcast(Jennifer Logan, Peter Hess)From Ordonez et al.

    Interannual OzoneVariations and trends.Goals: quantify impact on tropospheric ozone of:

    -changes in emissions of ozone precursors (NOx, CO, hydrocarbons)-changes in methane-changes in ozone in the lower stratosphere-dynamical variability including STE, ENSO, NAO/AO

  • From Wang et al, Modeled and Observed changes in CH4 growth rate.Goal: Match the observed methane trends and variability.Quantify: -the importance of changing anthropogenic and natural emissionsthe importance of OH variations. Procedure: use OH fields from the ozone hindcast in an inverse modeling calculation for methane emissions reconcile top-down and bottom-up emission estimates.

    Activity 1: Methane Hindcast (I. Bey, F. Dentener, A. Fiore, P. Hess, P. Bergamaschi)

  • AC&C Initiative, Activity 1: Hindcasts

    For models with whole atmosphere chemistry needs to build on recent CCMVal REF-B1 simulations (1960-2005). Full chemistry specifications need to include stratospheric forcings and boundary conditions. Default is to take REF-B1 input.As stratospheric model runs should start ~1960, tropospheric emissions need to be prescribed from this date.

  • AC&C Activity 4 Future ScenariosDrew Shindell, J-F Lamarque, Michael Schulz, (CCMVal Veronika Eyring)Phase 1: ACC-MIP (focus on troposphere)Time-slice experiments to complement AR5; CCMs and CTMs (need stratosphere)

    Emission sensitivity studiesSensitivity to IAM modeling of specific RCPSpread from using climatologyTimeslice runs including detailed chemistry diagnostics and separating aerosol indirect effects. Each run 4 years with prescribed SSTs taken from AR5 runs (SSTs should ideally be decadal means around given years), 2-month initialization suggested.

    8 historical times (1850I, 1890, 1910, 1930, 1950 I, 1970, 1990, 2000 I)

    5 future times (2010 I, 2030, 2050 I, 2070, 2100 I), each with 2.6 W/m2 Representative Concentration Pathway (RCP), 4.5 W/m2 RCP and 8.5 W/m2 RCP.

  • AC&C Activity 4Phase 1: ACC-MIPTimeslice experiments to complement AR5 (38 simulations, 160 years)Emission sensitivity studies

    Sensitivity to IAM modeling of specific RCPSpread from using climatologyRun at year 2050 (SSTs from #1), 1 year runs (+2-month initialization), models own distribution of given emission scaled uniformly:2.1: +100 Tg isoprene2.3: +20% biomass burning (all species)2.4: +50 Tg methane (3 year run in this case, only applicable for models with sources/sinks of methane rather than prescribed)2.5: +2 Tg N/yr lightning NOx

  • AC&C Activity 4Phase 1: ACC-MIPTimeslice experiments to complement AR5 (38 simulations, 160 years)Emission sensitivity studiesSensitivity to IAM modeling of specific RCP

    Spread from using climatologySame 4 year timeslice runs as in ACCMIP_1 for 2050 and 2100 but using emissions for the 2.6 and 4.5 RCPs from the other available IAMs. Runs without AIE only (as these are not climate runs)

  • What controls species distribution between 5km & tropopause?:Advection by large-scale winds Convection Wet scavengingDry DepositionStratosphere-Troposphere Exchange (CCMVal, SPARC)ChemistryIn situ production of ozone precursors

    -Start off looking at convection and scavenging processes, as these are the most uncertain and biggest knobs in the models, in particular when looking at UT.

    AC&C Initiative, Activity 2: Vertical Distributions Jos Rodriguez, Joyce Penner, Cline Mari, (SPARC representative AG?)

  • Activity 2 What to do?Most of the discussion initiated by senior people with little time but lots of opinions/ideasNeed heroes -- people who actually get things donePerhaps recent relevant activities may be exploited to enhance this activity.CCMValSCOUT-O3Mary Barths convection intercomparison activityAMMA

  • AC&C Initiative, Activity 2: Vertical DistributionsSCOUT-O3 Results (Hoyle et al 2009)Idealised tracers (e.g. 5-day lifetime)Comparison with Darwin CO profilesComparison of CTMs, CCMs and mesoscale models

  • Activities triggered and related to AC&C

  • EmissionsAn international effort was made to provide improved emissions 1850-2300, consistent across 2000 for anthropogenic (including shipping and aircraft) and biomass burning of reactive gases (not ODSs) and aerosolsHistorical (1850-2000) gridded anthropogenic and biomass burning emissions of reactive gases and aerosols: methodology and application.Jean-Franois Lamarque, Claire Granier, Tami C. Bond, O. Cooper,.Veronika Eyring, Angelika Heil, Mikiko Kainuma, Z. Klimont, David Lee, Catherine Liousse, J. R. McConnell , Aude Mieville, S. Oltmans, Bethan Owen, D. Parrish. Keywan Riahi, Martin Schultz, Drew Shindell, Steven Smith, Elke Stehfest, Allison Thomson, John Van Aardenne, Detlef Van Vuuren,

  • StatusEmissions1850-2000: available since July for all reactive gases and aerosols (1850 and 2000 earlier)2000-2100: RCP4.5/RCP8.5 available for reactive gases and aerosolsConcentrations (decadal averages): atmosphere-only simulations1850-2000: ozone (V. Eyring)1850-2000: aerosols (including dust and sea-salt) to be made available soon.2000-2100: RCP4.5/RCP8.5 running (NCAR)(Phil thinks) At least one RCP scenario still missing

  • Example of Impact of emissions(older versions, Flanner, McConnell and Rasch, unpublished)

  • Newer Emissions (Lamarque and Flanner, unpublished)

  • Remaining IssuesCCMVal desire to start hindcasts in 1960sTrop focus started in 1980sHindcasts for troposphere would benefit from emissions with annual time scale resolution (or shorter)E.g. fires?

    *Atmospheric growth rate anomalies for MATCH model results (black line; note that at MaceHead, MATCH CFC-11 and CFC-12 (dash-dotted lines) have been divided by 5 to keep them on scale)and AGAGE data (gray line). (top) N2O, (middle) CFC-11, and (bottom) CFC-12. (a, f, k) Cape Grim.(b, g, l) Samoa. (c, h, m) Barbados. (d, i, n) Trinidad Head. (e, j, o) Mace Head.

    Follows from early experiments by a number of groups to calibrate models. *Simulated, observed annual mean solar fluxes for india at the surface. *12-month running means of the normalizedmonthly anomalies with respect to the 19922004 meanannual cycle of lower free tropospheric ozone (blue) at(top) Jungfraujoch and (bottom

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