A 31-partner EC FP6 Integrated Project, developing:

1. Global and regional Earth-system Monitoring using Satellite and in-situ data A 31-partner EC FP6 Integrated Project, developing: • global modelling and data assimilation for greenhouse gases, reactive gases and aerosols • an integrated production system for the above • collaborative regional modelling, data assimilation and forecasting of reactive gases and aerosols to enable: • global monitoring of atmospheric composition • better daily regional air quality forecasts • estimation of surface fluxes of CO2 and other species • more comprehensive reanalysis products for recent years

2. GEMS tasks at ECMWF • Coordinate Project(Tony Hollingsworth; Adrian Simmons) • Greenhouse gases(Richard Engelen, Soumia Serrar) • Start on CO2, then CH4 • Develop modelling and data assimilation, and collaborate with partners in use of analyses to infer sources and sinks for CO2 and CH4 • Reactive gases(Antje Dethof, Johannes Flemming, Luke Jones) • Couple main forecast model with global CTMs • Carry O3, CO, NO2, SO2 and HCHO in main model and develop data assimilation • Aerosols(Angela Benedetti, Jean-Jacques Morcrette, Johannes Kaiser) • Add to model, based on externally-produced parameterizations • Develop assimilation of retrievals, then radiances • Integrate above components, and run past periods • Acquire data, and provide support for regional air-quality forecasting(Martin Suttie, Miha Razinger)

3. Assimilation of AIRS radiances by GEMS system Excess modelled CO2 at ~500hPa, 12UTC 20 August 2003, from GFEDv2 8-day fire emissions Cross-sections of modelled/analysed CO2, taken along modelled fire plume Without assimilation With AIRS assimilation

4. Validation of first extended AIRS assimilation Comparisons with flight data over Hawaii (courtesy of Pieter Tans, NOAA/ESRL) shows a clear improvement of the analysis over a free-running model. The top plot shows a best-case individual comparison (11 May 2003). The bottom plot shows an average over all available flight profiles between 1 January and 31 August 2003.

5. Validation of first extended AIRS assimilation Comparisons with flight data over Hawaii (courtesy of Pieter Tans, NOAA/ESRL) shows too large values later in the year in both the free-running model and the analysis Work on the specification of background errors and on the bias-correction of the AIRS radiances is being undertaken to remedy this in the short term. Improving surface fluxes is the long-term aim.

6. Validation of first extended AIRS assimilation Comparisons with flight data over Surgut, Siberia (courtesy of Toshinobu Machida, NIES) shows too large values from mid-year in both the free-running model and the analysis Work on the specification of background errors and on the bias-correction of the AIRS radiances is being undertaken to remedy this in the short term. Improving surface fluxes is the long-term aim.

7. CO2 flux inversion from first extended AIRS assimilation (F.Chevallier, LSCE)

8. Monitoring of CO2 retrievals from SCIAMACHY by GEMS data assimilation system Standard deviation (ppmv) of (Obs – Background) Retrievals from University of Leicester Standard deviation (ppmv) of (Obs – Background) Retrievals from University of Bremen

9. Other recent and ongoing activities • Participation in TRANSCOM model comparisons • Addition of methane as a model/analysis variable • Assessment of GEOLAND C-Tessel model for land carbon fluxes • Preparations for assimilation of IASI, SCIAMACHY CH4, OCO and GOSAT data

10. Time series (850 hPa) Vertical profiles ~55 flights (before heatwave) heatwave MOZART modelled MOZAIC measured MOZART modelled MOZAICmeasured Ozone measured modelled Ozone CO O3 (ppb) height [m] CO measured modelled CO (ppb) O3 (ppb) CO (ppb) July August Comparison of CO and O3 from MOZART CTM withMOZAIC aircraft data for Frankfurt, summer 2003 Martin Schultz, Olaf Stein, Carlos Ordonez

11. Assimilation of MOPITT data leads to increased total column values over Europe during the 2003 heat wave and an improved fit to MOZAIC data over Frankfurt Assimilation Assimilation of MOPITT CO Control Control

12. Total column CO fields: Mean from 15 to 30 July 2003 Control Assimilation Assimilation - Control Assimilation of MOPITT CO columns leads to reduced values in the tropics and increased values in the extratropics. Unit: 1018 molec/cm2

13. GEMS ECMWF ASSIM Control Comparisons with MOSAIC data for Osaka CO with and without assimilation of MOPITT data in GEMS system O3 from GEMS (without assimilation)and standard ECMWF systems

14. Total column ozone [DU], from assimilation, 31 Jan 2003 • Assimilated data: • SCIAMACHY total ozone columns • MIPAS ozone profiles • SBUV ozone layers • GOME ozone profiles Control Assimilation Improved total column ozone field in comparison with TOMS TOMS

15. Comparisons with MOSAIC data: impact of assimilation Assimilation of satellite observations of ozone leads to an improved fit of GEMS tropospheric ozone profiles to MOZAIC data Control Assimilation

16. Total column HCHO GEMS: 15-30 July 2003 Unit: 1015 molec/cm2 GOME: July 2001 http://www.gse-promote.org/

17. Interconversion operator: depends on SZA, O3 concentration, slant O3 column and temperature JNO2 calculation based on TM5 routine NO2 assimilation • Fast NO2/NOx interconversion causes problem for IFS/CTM coupling • -> Use NOx as IFS tracer and use interconversion operator for NO2 • Current reactive-gas analysis for 2003 assimilates CO and ozone, with NO2 data passive for monitoring purposes • Work continues on NO2/NOx operator and the use of a normalized control variable for NOx, following treatment of humidity in ECMWF system • Analysis for 2003 (or part of it) likely to be rerun • with NO2 assimilation

18. Real-time forecasts (without reactive-gas assimilation)

19. Black carbon: biogenic source Black carbon: fossil-fuel source Aerosol model development • Model now includes: • Sea salt (3 bins, with parametrized source) • Desert dust (3 bins, with parametrized source) • Black carbon and organic matter (hydrophilic and hydrophobic, with specified sources) • Sulphate aerosol(with specified precursor emissions) • Separate scheme for stratospheric aerosols • Development (validation, improved modelling and emissions) is ongoing

20. Real-time forecasts (without aerosol data assimilation) AERONET data are being received in near real time, and will be used in routine model assessment

21. Comparison of aerosol optical depth with MODIS observations for August 2003 Control Assimilation increases values over north-east Asia, Central Africa and America, and reduces values over tropical Atlantic and Southern Ocean Accumulation in Arctic is under investigation MODIS observations Assimilation Experiments are averaged from 1 to 15 August 2003

22. UV-radiation products UV-radiation processor now incorporated in ECMWF model (J.-J. Morcrette, in collaboration with A. Arola, FMI) Run pre-operationally to produce web plots of biologically effective dose for total sky and clear sky

23. GEMS: Plans for global system 2007-2009 • Refine and integrate assimilation systems for greenhouse and reactive gases, and aerosols • Complete initial analyses for 2003/4, then analyse 2003-2007 • Use analyses in flux inversions • Run prototype near-real-time system for reactive gases and aerosols • Supply driving meteorological fields and composition boundary conditions to regional air-quality forecasting systems • Archive, validate and display results • Prepare for and integrate with follow-on pre-operational activity