1. Institut für Physik der Atmosphäre Ensemble Climate-Chemistry simulations for the past 40 years Volker Grewe and the DLR/MPI Team Institut für Physik der Atmophäre DLR-Oberpfaffenhofen Germany Volker.Grewe@dlr.de Martin Dameris, Veronika Eyring, Fabian Mager, Michael Ponater, Tina Schnadt, Andrea Stenke - DLR Oberpfaffenhofen Benedikt Steil, Christoph Brühl, Patrick Jöckel - MPI- Mainz Marco Giorgetta, Claudia Timmreck, MPI-Hamburg

2. Institut für Physik der Atmosphäre ECHAM4.L39(DLR) = E39 Atmosphere circulation model Global spectral model with semi-Lagrangian advection of water vapour, cloud water and tracers Resolution: T30, 39 layers, top layer centered at 10 hPa (30 km) Parameterizations of radiation, clouds, precipitation, convection, diffusion CHEM = CChemistry-Module (family concept) Transported species: H 2 O, CH 4, N 2 O, HCl, H 2 O 2, CO, CH 3 O 2 H, ClONO 2, HNO 3 +NAT, ICE, ClO x, NOX, OX 37 species and 107 gas-phase reaction Methane oxidation, PSC formation, 4 heterogeneous reactions on PSCs Parameterization of dry/wet deposition, lightning and surface emissions Interactively coupled at every timestep E39/C Climate-Chemistry Model

3. Institut für Physik der Atmosphäre Coupling of Dyamics and Chemsitry in E39/C

4. Institut für Physik der Atmosphäre Simulation of the Earths atmosphere from 1960 to 2000 Simulation is based on climate chemistry model E39/C with additional forcings: Emissions of NO x, CO, CO 2, N 2 O, CH 4, CFCs, as observed or estimatd by IPCC QBO nudged in tropical stratosphere Volcanoes regarded (Agung, El Chichon, Pinatubo) for chemistry and radiation Observed sea surface temperatures (Hadley-GISS) 11 year solar cycle No other forcing, free running climate chemistry model

5. Institut für Physik der Atmosphäre Total Ozone [DU] High variability > than in time-slices Solar cycle in tropics Ozone hole starts 80s Global ozone -15 DU

6. Institut für Physik der Atmosphäre Tropospheric ozone column (DU) High variability Global increase: 4 DU Small effects on SH

7. Institut für Physik der Atmosphäre Simulated evolution of cloud to ground lightning 1960 to 2000 El Nino events

8. Institut für Physik der Atmosphäre Ensemble 50 hPa temperature

9. Institut für Physik der Atmosphäre Ensemble total ozone

10. Institut für Physik der Atmosphäre Ensemble tropospheric total ozone

11. Institut für Physik der Atmosphäre Lightning

12. Institut für Physik der Atmosphäre Summary CCM/CTM Models are ready for transient simulations ACCENT modelling acitivity: Ensemble simulations Capability of models (-> Comparison to measurements) Attribution perhaps possible? TemperatureTropospheric Ozone Column ? BUT

13. Institut für Physik der Atmosphäre Fully coupled CCM simulations require additional diagnostics in order to separate various effects. E.g. NOx and ozone tagging diagnostics

14. Institut für Physik der Atmosphäre Approach: Tagging of NO y and ozone molecules 1st step: For each source i=1,..., n (n=8) define a NO y tracer (X i ) 2nd step: For each NO y tracer define an ozone tracer (Y i ) and an ozone tracer (Y n+1 ) for ozone production by O 2 photolysis Attribution of ozone increase to NO x emissions

15. Institut für Physik der Atmosphäre

16. Institut für Physik der Atmosphäre

17. Institut für Physik der Atmosphäre

18. Institut für Physik der Atmosphäre Tropical past ozone changes 30S-30N 200-500 hPa 500-1000 hPa Ozone tracer mass Lightning most important source for tropical ozone In UT: stratospheric intrusions also important

19. Institut für Physik der Atmosphäre Interannual variability in the tropics Solar cycle effects stratospheric ozone leading to weak UT ozone variations ( 5%) Stratospheric O 3 and lightning important for inter-annual variations Industry and land transportation responsible for trends Upper troposphere Lower troposphere