Atmospheric Chemistry and the Climate System by zrn20302

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									Atmospheric Chemistry
and the Climate System

Martin G. Schultz, Thomas Diehl, Claire Granier, Judith
  Hölzemann, Shyam Lal, Bärbel Langmann, Ulrike
              Niemeier, Sebastian Rast

      Max Planck Institute for Meteorology, Hamburg

       Scientific Advisory Committee Meeting, November 25-26, 2002
 Scientific Advisory Committee Meeting, November 25-26, 2002




                   Feedbacks Chemistry  Climate

                                                                                            Strat.-trop.
 Altitude




                                         Deposition of
                                         HNO3, NOx, SO2, ozone                              Exchange



     Ozone              Aerosol-Cloud
     Particles          Interactions                                        Lightning
Absorption and                          Eutrophication,                     NOx Prod.
Scattering of Radiation                 Fertilization,
                                        Acidification



             Emissions of
             DMS, VOCs, NOx, CO, ...
                                             +
                                                                                   Transport pathways
                                                               Scavenging
                                        Reaction               Rates
            Release of ozone and        Rates
            sulfate precursor species




                                                                Martin G. Schultz et al.: Atmospheric Chemistry …
Scientific Advisory Committee Meeting, November 25-26, 2002



               The oxidizing capacity of the
                atmosphere - Example for a
                  bidirectional feedback
                                              CO




                 CH4                            OH ?                      VOC




                                                                         O3
                                              NOx



                                                              Martin G. Schultz et al.: Atmospheric Chemistry …
Scientific Advisory Committee Meeting, November 25-26, 2002




         Tropospheric Ozone Budget
     and Long-range transport of pollution




                                                                                         from IPCC 2001

                                                              Martin G. Schultz et al.: Atmospheric Chemistry …
Scientific Advisory Committee Meeting, November 25-26, 2002




      Factors controlling the tropospheric
                 ozone budget

                                                         Stratospheric
                                                             Ozone


                          Chemistry
                      VOC    OH      NO2
                                           O2
                                                          Tropospheric                     Dynamics
                       RO2   HO2     NO                      Ozone                         Transport


                          Emissions                                                      Temperature
                     (NOx, VOC, CO, CH4)                                                   Humidity



                                                              Martin G. Schultz et al.: Atmospheric Chemistry …
Scientific Advisory Committee Meeting, November 25-26, 2002




                              Tropospheric ozone trend
                                           Maximum at Zugspitze
                                                   Maximum mean
          Ozone concentrations in maritime air masses 8-hour 8-hour mean
                                                   ozone concentrations
                                           ozone concentrations at
                                                    surface stations
                                           English at Britishstations
                                                                         from Eurotrac S&I, 2002
                         70                          O3 Zugspitze
                         60
           Ozone (ppb)




                         50

                         40

                         30

                         20
                                1980   1985         1990          1995           2000
                                                                         from Scheel et al., 2002

                                                              Martin G. Schultz et al.: Atmospheric Chemistry …
Scientific Advisory Committee Meeting, November 25-26, 2002



     Long-range transport of air pollution:
         Export from North America




                                                              Martin G. Schultz et al.: Atmospheric Chemistry …
Scientific Advisory Committee Meeting, November 25-26, 2002



     Long-range transport of air pollution:
             Import into Europe
                    Western Europe                            Eastern Europe




                     North America                                East Asia




   Simulated CO concentrations over Europe, May 2001, ca. 850 hPa
                                                              Martin G. Schultz et al.: Atmospheric Chemistry …
Scientific Advisory Committee Meeting, November 25-26, 2002




         Interannual variability in transport
   Ozone difference (Sep. 1997-Sep. 1998)
                                                         Changes in transport pathways
                                                         lead to significantly different
                                                         trace gas concentrations.

                                                         Direct effect: different
                                                         pathway from emission sources
        -20
         -20   -10 -5 -2
                -10    -2   2   5   10    20     ppb
                                                         to receptor region
   CO difference (Sep. 1997-Sep. 1998)

                                                         Indirect effect: north-south
                                                         shift/vertical transport 
                                                         different chemistry
                                                         (temperature, radiation, humidity)
Same emissions, winds from ECMWF
                                                              Martin G. Schultz et al.: Atmospheric Chemistry …
 Conceptual picture of major transport
              pathways

                           WCB


                              Asia
 North
America

    WCB




                             boundary layer flow
                Europe       free trop. transport
Scientific Advisory Committee Meeting, November 25-26, 2002



        Using chemical measurements on
      aircraft to quantify export and import
                      fluxes

  •    Direct involvement in large-scale field experiments (e.g. NASA
       TRACE-P, North Pacific, spring 2001; MINOS, Crete, summer
       2001)
  •    Modeling support for analysis of other field experiments (e.g.
       INDOEX, 1998, 1999; CONTRACE, 2001; BIBLE, 1997, 1998)




                                                              Martin G. Schultz et al.: Atmospheric Chemistry …
    Scientific Advisory Committee Meeting, November 25-26, 2002




          CO tracer forecasts during TRACE-P

before the campaign: planning of flight patterns                      Objectives:
during the campaign: daily forecasts of CO
after the campaign: analysis with tagged CO                           Determine the chemical
and full chemistry model                                              composition of the Asian
                                                                      outflow over the western Pacific
                                                                      in spring in order to understand
                                                                      and quantify the export of
                                                                      chemically and radiatively
                                                                      important gases and aerosols, and
                                                                      their precursors, from the Asian
                                                                      continent.

                                                                      Determine the chemical
                                                                      evolution of the Asian outflow
                                                                      over the western Pacific in spring
                                                                      and to understand the ensemble of
                                                                      processes that control this
                                                                      evolution.

                                                                  Martin G. Schultz et al.: Atmospheric Chemistry …
Scientific Advisory Committee Meeting, November 25-26, 2002



              Example for model evaluation
       Comparison of model results along TRACE-P flight track DC-8
            for 7 March 2001 (local flight out of Hong Kong)



                                           observed             altitude

                                                    model




                                                              Martin G. Schultz et al.: Atmospheric Chemistry …
Scientific Advisory Committee Meeting, November 25-26, 2002



             Evaluating the forecast quality
               Example for 7 March 2001, 0600 UTC, ca. 850 hPa




                           analysis                                 18-h forecast




                   66-h forecast                                  114-h forecast


                                                              Martin G. Schultz et al.: Atmospheric Chemistry …
Scientific Advisory Committee Meeting, November 25-26, 2002




           Measurement-Model Comparison
                   INDOEX 1999




                                                                                  INDOEX 1999

                                                                                   Observations
                                                              60                   MOZART
                                            Avg Ozone (ppb)


                                                              40




                                                              20




                                                              0
                                                                   20   30         40             50       60          70

                                                                                    Day of Year

                                                                         Martin G. Schultz et al.: Atmospheric Chemistry …
Scientific Advisory Committee Meeting, November 25-26, 2002




        Linking global and regional models
            Effect of time-varying boundary conditions on Ozone
                         concentrations over Germany




           global model                global+regional model                    regional model
                                                                                           Ozone in ppb

                                                              Martin G. Schultz et al.: Atmospheric Chemistry …
Scientific Advisory Committee Meeting, November 25-26, 2002




              Interpretation of satellite data
                                                  Use of models to determine air
                                                  mass factor (dependent on geometry,
                                                  zenith angle, albedo, ...)

                                                                               Slant column
                                                   Air mass factor =
                                                                             Vertical column




                                                                 Collaboration with Institute
                                                                 for Remote Sensing, University
                                                                 of Bremen


                                                              Martin G. Schultz et al.: Atmospheric Chemistry …
Scientific Advisory Committee Meeting, November 25-26, 2002




                                          Outlook
Objective:
to provide a quantitative and consistent
description of the global tropospheric
budget of ozone

Tools:
full chemistry model MOZART, ECHAM
tagged CO tracer model, and regional
model REMO

Coordinating EU project:
REanalysis of TROpospheric
chemical composition over
the past 40 years


                                                              Martin G. Schultz et al.: Atmospheric Chemistry …
Scientific Advisory Committee Meeting, November 25-26, 2002




   Biomass burning emissions


   • Significant emission source for many trace gases (and aerosol)
   • Large interannual variability in distribution and magnitude
   • Competition between man-made and natural fires
   • Fire characteristics ecosystem dependent
   • Ecosystems respond to fire
   • Impact of climate change



                                                              Martin G. Schultz et al.: Atmospheric Chemistry …
Scientific Advisory Committee Meeting, November 25-26, 2002




       A new global inventory for biomass
        burning emissions using satellite
          observations of burned areas




M = EF x A x  x afl                                                      GLOBSCAR data from ESA/ESRIN


                                                              Martin G. Schultz et al.: Atmospheric Chemistry …
Scientific Advisory Committee Meeting, November 25-26, 2002




      Assessing the variability of biomass
              burning emissions
           OCTOBER „Climatology“
                                                      Use of active fire counts (ATSR)
                                                      to scale a climatological emission
                                                      inventory




                                                              Martin G. Schultz et al.: Atmospheric Chemistry …
 Scientific Advisory Committee Meeting, November 25-26, 2002




         Case study 1: Indonesia 1997/1998
Scaled inventory from global model                Aerosol simulations from regional model REMO




Importance of peat fires!
(90% of emissions from Borneo)
Severly understimated when using
satellite data to estimate emissions

                                                               Martin G. Schultz et al.: Atmospheric Chemistry …
Scientific Advisory Committee Meeting, November 25-26, 2002




   Case Study 2: Sydney, December 2001




                                                                                  AVHRR image 01/01/2002




                                                                                   MODIS AOD average
                                                                                   (courtesy A. Chu, NASA)


  Model simulation (MOZART) in T85L47, ECMWF winds, daily emission
  estimates using MODIS fire counts [near-surface CO in ppb]

                                                              Martin G. Schultz et al.: Atmospheric Chemistry …
Scientific Advisory Committee Meeting, November 25-26, 2002




                                          Outlook

• Refine of global inventory, extension to multiple years
• Investigate impact of Indonesian peat fire aerosol on meteorology
• Analyse role of volcanoes for sulfur content in Indonesian peat
   fire emissions
• Contrast Sydney 2001 with Sydney 2002
• Develop methods for estimating biomass burning emissions based on
   meteorological parameters




                                                              Martin G. Schultz et al.: Atmospheric Chemistry …

								
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