1. INTEGRATED GLOBAL ATMOSPHERIC CHEMISTRY OBSERVATIONS (IGACO) - 1 - Strategy for Integrated Global Atmospheric Chemistry Observations (IGACO) Joerg Langen (ESA-ESTEC) on behalf of the IGACO Theme Team

2. INTEGRATED GLOBAL ATMOSPHERIC CHEMISTRY OBSERVATIONS (IGACO) - 2 - Integrated Global Observing Strategy (IGOS) Partnership (1/3) Partners the Global Observing Systems (GOS/GAW, GOOS, GTOS, GCOS) the international agencies which sponsor the Global Observing Systems (FAO, ICSU, IOC of UNESCO, UNEP, UNESCO, WMO) the Committee on Earth Observation Satellites (CEOS) the International Group of Funding Agencies for Global Change Research (IGFA) the international global change research programmes (WCRP, IGBP)

3. INTEGRATED GLOBAL ATMOSPHERIC CHEMISTRY OBSERVATIONS (IGACO) - 3 - Integrated Global Observing Strategy (IGOS) Partnership (2/3) addresses the need to join forces in Earth Observation globally fill gaps in existing observation systems integrate diverse data sets and strengthen institutional capacity to implement integrated global observations ensure long-term continuity in observation, supporting data policies, enhanced product processing chains, better archiving and improved accessibility to the information products. improve communication between space agencies, agencies supporting in-situ observing systems, scientific research programmes, and governmental agencies

4. INTEGRATED GLOBAL ATMOSPHERIC CHEMISTRY OBSERVATIONS (IGACO) - 4 - Integrated Global Observing Strategy (IGOS) Partnership (3/3) Themes Ocean Global Carbon Cycle Global Water Cycle Geo-Hazards Atmospheric Chemistry (IGACO) Coastal (incl. Coral-Reef) Land

5. INTEGRATED GLOBAL ATMOSPHERIC CHEMISTRY OBSERVATIONS (IGACO) - 5 - The IGACO Team - Authors L. Barrie (WMO) (co-chair) J. Langen (ESA) (co-chair) P. Borrell (P&PMB Consultants) (secretary) O. Boucher (Univ. Lille) J. Burrows (Univ. Bremen) C. Camy-Peyret (CNRS/LPMA) J. Fishman (NASA-L) E. Hilsenrath (NASA-G) D. Hinsman (WMO) C. Granier (CNRS/SA) H. Kelder / A. Goede (KNMI) V. Mohnen (SUNYA) T. Ogawa (JAXA) T. Peter (Univ. Zürich) M. Proffitt (WMO) A. Volz-Thomas (FZ Jülich) P.-Y. Whung (NOAA) P. Simon (Inst.d’Aeronomie Spatiale de Belgique)

6. INTEGRATED GLOBAL ATMOSPHERIC CHEMISTRY OBSERVATIONS (IGACO) - 6 - The IGACO Team - Reviewers U. Platt (Univ. Heidelberg) H. Akimoto (Adv. Sci & Tech Research Centre, Tokyo) G. Brasseur (MPI Meteorology, Hamburg) M.-L. Chanin (SPARC / CNRS, Paris) P. J. Crutzen (MPI Atmospheric Chemistry, Mainz) N. Harris (European Ozone Research Coordination Unit, Cambridge / UK) D. Jacob (Harvard Univ.) M. J. Molina (MIT, Cambridge / USA) S. Oltmans (NOAA-CMDL) A. M. Thompson (NASA – G)

7. INTEGRATED GLOBAL ATMOSPHERIC CHEMISTRY OBSERVATIONS (IGACO) - 7 - The Objectives of IGACO defining a feasible strategy for deploying a global atmospheric chemistry observation system with comprehensive coverage of key atmospheric gases and aerosols establishing a system for integration of ground- based, airborne and satellite air chemistry observations using atmospheric models making the integrated observations accessible to science, responsibles for environmental policy development and weather / environmental prediction centres To initiate a process leading to the implementation of globally coordinated observation and integration programmes within 10 years, by:

8. INTEGRATED GLOBAL ATMOSPHERIC CHEMISTRY OBSERVATIONS (IGACO) - 8 - IGACO Strategy  Identify the major societal and scientific issues associated with atmospheric chemistry and composition change;  Recommend a list of target observables using a well defined set of criteria;  Establish the requirements for observations of atmospheric composition and their analysis, integration and utilisation;  Review existing observational systems for the target variables as well as data processing and modelling;  Make recommendations and propose a structure for implementation.

9. INTEGRATED GLOBAL ATMOSPHERIC CHEMISTRY OBSERVATIONS (IGACO) - 9 - The Issues 1.Air pollution / air quality 2.Climate 3.Stratospheric ozone depletion 4.Atmospheric self-cleansing capability (“oxidising power”)

10. INTEGRATED GLOBAL ATMOSPHERIC CHEMISTRY OBSERVATIONS (IGACO) - 10 - Issue 1 : Air Pollution Enhanced levels of aerosols, ozone, NO x, CO etc. in the lower atmosphere Sources: industrial activities, power plants, traffic, heating, anthropogenic biomass burning Deposition effects: acid rain, eutrophication of lakes, damage to the biosphere. Respiratory and cardio-vascular diseases (air pollution kills 60000/y in USA: source EPA) Globalisation through industrialisation and intercontinental transport of pollution IGACO Products:  Localisation and quantification of pollution sources, identification of chemical processing, transport pathways and sinks  Air quality forecast  Monitoring of conventions (e.g. UN-ECE LRTAP) and national legislation  support of impact assessment (e.g. air pollution  human health)

11. INTEGRATED GLOBAL ATMOSPHERIC CHEMISTRY OBSERVATIONS (IGACO) - 11 - Issue 2 : Climate Complex coupling between radiation, transport and chemistry (“climate-chemistry interaction”) Greenhouse gases (CO 2, CH 4, O 3, N 2 O, Halocarbons) and aerosols emitted by human activities are primary forcing agents of climate change. Atmospheric lifetime of CH 4, O 3 and aerosols are chemically controlled High climate sensitivity to GHG conc. in the tropopause region Stratosphere-troposphere-exchange is a major factor for stratospheric H 2 O and upper tropospheric O 3 Climate change impacts on sources, transport, removal of chemicals and hence, distribution of atmospheric constituents IGACO Products:  Scientific assessment of climate change (IPCC, UNFCCC)  Climate prediction and weather forecasting  Contribution to convention monitoring (e.g.CH 4 for Kyoto protocol)

12. INTEGRATED GLOBAL ATMOSPHERIC CHEMISTRY OBSERVATIONS (IGACO) - 12 - Issue 3 : Stratospheric Ozone Depletion Dramatic ozone losses in polar spring (“stratospheric O 3 hole”, last year: diminished early due to circulation anomaly, 2003: full extent)  4% O 3 depletion at mid-latitudes  10% increase in surface UV irradiance Potential for increase in skin cancer and crop damage Source of problem : anthropogenic halocarbon emissions Montreal protocol effective for chlorine but not bromine Recovery time uncertain due to stratospheric cooling and H 2 O increase. IGACO Products:  Monitoring of Vienna Convention / Montreal Protocol and amendments  UV irradiance forecast  Scientific assessment of stratospheric ozone evolution and recovery

13. INTEGRATED GLOBAL ATMOSPHERIC CHEMISTRY OBSERVATIONS (IGACO) - 13 - Issue 4 : Oxidising Power Atmospheric self-cleansing depends on the “detergent” OH OH is very short lived and maintained by a balance between complex “source and sink” chemistry Impact of atmospheric change on OH difficult to predict, due to non-linear chemistry, small-scale processes and uncertainties in sources Effects long-term evolution of chemical balances in the atmosphere  major feedback to all other issues as well as cycles of toxic substances (POPs and mercury) IGACO Products:  Scientific assessment of chemical and physical processes, in particular distinction between anthropogenic trends and natural variabilities, as relevant to the other issues

14. INTEGRATED GLOBAL ATMOSPHERIC CHEMISTRY OBSERVATIONS (IGACO) - 14 - TECHNOLOGY INDEPENDENT LIST OF OBSERVABLES Consideration Of The Chemistry of: Stratosphere, Free Troposphere, Air Quality, Climate The Filter: Based on: (i) Relevance To Key Issues, (ii)Availability Of Many Types Of Observations (iii) Availability of Integration Tools TARGET LIST OF OBSERVABLES By Issue

15. Targeted Variables IGACO Group 1 & Group 2 Chemical species Air Quality Oxidation Capacity Climate Stratospheric Ozone Depletion O3O3 CO UV-A j(NO 2 ) UV-B j(O 3 ) H 2 O (water vapour) HCHO C2H6C2H6 active nitrogen: NO x = NO+NO 2 reservoir species: HNO 3 SO 2 active halogens: BrO, ClO, OClO reservoir species: HCl, ClONO 2 sources: CH 3 Br, CFC-12, CFC-11, HCFC-22 aerosol optical properties CO 2 CH 4

16. INTEGRATED GLOBAL ATMOSPHERIC CHEMISTRY OBSERVATIONS (IGACO) - 16 - Critical Ancillary Variables IGACO Ancillary Variables Air Quality Oxidation Capacity Climate Stratospheric Ozone Depletion T P Wind Speed (u,v,w) Cloud Top Height Cloud Coverage Albedo Lightning Flash Frequency Fire Occurrence Solar Radiation

17. INTEGRATED GLOBAL ATMOSPHERIC CHEMISTRY OBSERVATIONS (IGACO) - 17 -

18. INTEGRATED GLOBAL ATMOSPHERIC CHEMISTRY OBSERVATIONS (IGACO) - 18 -

19. INTEGRATED GLOBAL ATMOSPHERIC CHEMISTRY OBSERVATIONS (IGACO) - 19 - Target and threshold requirements for aerosol

20. The Existing Observational System A.Routine ground-based measurements (in-situ and remote sensing) incl. balloon Accuracy, long-term history, validation source, local/regional relevance B.Systematic aircraft measurements High-resolution tropospheric profiles, tropopause measurements C.Satellite observations Global coverage, uniform data quality D.Chemical models and data assimilation tools Integration, data analysis and exploitation

21. Stratospheric O 3

22. INTEGRATED GLOBAL ATMOSPHERIC CHEMISTRY OBSERVATIONS (IGACO) - 22 - A. Routine Ground-Based Measurements Ozone sonde network for vertical profiles(WMO, NASA) Dobson/Brewer network total column ozone (WMO, space agencies) Networks for CO 2, CH 4, N 2 O (WMO with NOAA/CMDL major player) Aerosol optical depth (WMO, NASA)  Calibration issues  Diverse organisational structures Global Atmosphere Watch (GAW) coordinates WMO network with contributing-partner networks to complete global coverage.

23. ESTIMATED GLOBAL OZONESONDE NETWORK: 2003 Stations with data submitted since at least 1 Jan 1999 Compliments of WOUDC, Toronto Ed Hare Manager. Note that this map changes constantly as data is submitted to the data centre. Suggestions to correct any omissions are welcome by GAW. The red symbols represent sites of contributing partner NASA/SHADOZ.

24. Courtesy of the World Data Centre for Greenhouse Gases Japan Meteorological Agency. Note that this map changes constantly as data is submitted to the data centre. Suggestions to correct any omissions are welcome by GAW.

26. INTEGRATED GLOBAL ATMOSPHERIC CHEMISTRY OBSERVATIONS (IGACO) - 26 - B. Systematic Aircraft Measurements MOZAIC – O 3, H 2 O, CO, NO y, since 1994 and grab sampling package – CO 2, CH 4, CO, since 1993 CARIBIC – one aircraft, new, many species, now twice per month Vertical profiles CO 2, CH 4, initiated, frequent flights GAW led by NOAA-CMDL Several demonstration programmes for aerosols (ARM and NOAA/CMDL)  Unique measurements but still limited species / space / time coverage  Sampling biases

27. C. Satellite Observations Near-continuous record of total column ozone since 1978, commitments for continuation well into next decade; demonstration of tropospheric ozone retrieval CO, NO 2, HCHO, BrO, SO 2 are under development Aerosol optical depth, considerable coverage over oceans and, now, over continents as well. Good coverage of stratospheric species in research mode, much less in troposphere  Spatial and temporal resolution inadequate for troposphere  Vertical resolution inadequate for UTLS  Very limited commitments after 2008  Need more systematic calibration/validation and archiving

28. D. Chemical Models and Data Assimilation Tools Chemical transport models (chemistry driven by external met data) Interactive chemistry-climate models (chemical processes part of the climate simulation) Weather forecast models with ozone and aerosols dynamically incorporated.  Spatial resolution needs improvement (variability within model grid box, sampling consistency between model and measurements)  Quality of emission inventories insufficient Chemical data assimilation (incl. forecast)  Demonstrated and developing fast Major application inverse modelling (retrieval of surface sources and sinks)  starting but inhibited by lack of observational data

29. INTEGRATED GLOBAL ATMOSPHERIC CHEMISTRY OBSERVATIONS (IGACO) - 29 - RECOMMENDATIONS A Phased Approach: (I)Short Term: 2004 to 2014 Integrate data of group 1 species Build up observation system for group 2 species (II)Long Term: beyond 2014 Operate complete integrated observation system

30. INTEGRATED GLOBAL ATMOSPHERIC CHEMISTRY OBSERVATIONS (IGACO) - 30 -

31. Observations  Adding missing ground-based measurements for Group 1 variables, and, where feasible, some of those from Group 2 (in situ, total column, active and passive profiling, and balloon sonde)  Developing robust routine aircraft measurements for all the feasible species. An instrument development programme aimed at the operating environment of aircraft is most desirable  Initiating immediately the planning of a network of satellite measurements for the long term with priority to adding GEO instruments to a complementary set of LEOs Establish long-term continuous observation system satisfying IGACO data requirements by:

32. The Long Term Satellite System Should Include: A tropospheric mission to address air quality, climate and oxidizing power: Geostationary satellites (or larger number of polar orbiting satellites) with nadir-viewing instruments. An upper tropospheric/lower stratospheric mission to address climate-chemistry interaction and stratospheric ozone depletion : Polar orbiting sun-synchronous satellites with limb-viewing instruments

33. Quality Assurance Ground-based and routine aircraft data :  Use internationally traceable standard reference materials or reference methods  Conduct routine comparison activities to link diverse measurements together  harmonize data quality between stations and networks

34. Quality Assurance Satellite Operations Should Include:  Pre-launch instrument calibration & characterisation and in-flight calibration  Long term ground validation  Systematic validation of vertical profile observations

35. INTEGRATED GLOBAL ATMOSPHERIC CHEMISTRY OBSERVATIONS (IGACO) - 35 - Data Processing and Distribution Should Include  Development of automated retrieval of total column and profile data from existing and planned satellites for all targeted variables  Systematic reprocessing of data following algorithm improvements  Establishment of universally recognised data distribution protocols  Establishment of multi-stakeholder World Integrated Data Archive Centres (WIDACs) for targeted variables

36. INTEGRATED GLOBAL ATMOSPHERIC CHEMISTRY OBSERVATIONS (IGACO) - 36 - Models : the tool for integration  develop comprehensive chemical modules in weather and climate models with appropriate data assimilation  develop inverse modelling using data assimilation to improve chemical source and sink characterization

37. INTEGRATED GLOBAL ATMOSPHERIC CHEMISTRY OBSERVATIONS (IGACO) - 37 - IGACO Implementation Phases & The Targeted Variables Divided into 2 groups: Group 1: O 3, H 2 O, CO 2, CO, NO 2, BrO, the CFCs and aerosol optical properties {Global observations, modelling capabilities and assimilation tools available – maintenance and some gap filling of observations required} Group 2: CH 4, HCHO, C 2 H 6, SO 2, HNO 3, ClONO 2, NO, ClO, OClO, HCl, CH 3 Br, and the halons {Satellite observations in demonstration mode, sparse network of in-situ data – much development of observational programme needed}

38. INTEGRATED GLOBAL ATMOSPHERIC CHEMISTRY OBSERVATIONS (IGACO) - 38 - IGACO Implementation Phase I (2004-2014)  Implement IGACO system for all group 1 species  Develop retrieval algorithms, quality control system, models  Upgrade ground-networks and routine aircraft observations  Plan and initiate the long term observational system including the space component.

39. INTEGRATED GLOBAL ATMOSPHERIC CHEMISTRY OBSERVATIONS (IGACO) - 39 - IGACO Implementation Phase II (Beyond 2014)  Establish an operational IGACO system for all group 1 and group 2 species, including fleet of satellites  Maintain ground networks for all group 1 and group 2 species  Maintain routine aircraft programme for group 1 and group 2 species with improved global coverage  Refine models and data assimilation

40. INTEGRATED GLOBAL ATMOSPHERIC CHEMISTRY OBSERVATIONS (IGACO) - 40 - IGACO status and further schedule Draft report available Comments received from IGOS-P and IGACO review team Refinements and implementation of comments ongoing Presentation to CEOS-SIT, February 2004 Presentation to IGOS-P and aim for approval, May 2004

41. INTEGRATED GLOBAL ATMOSPHERIC CHEMISTRY OBSERVATIONS (IGACO) - 41 - Decide what needs to be changed Deploy improved observational assets & improve use of existing ones Enhance the product processing chain Collect Observa- tions and Generate Products Redesign systems Change the Observational systems Implementation Monitor progress The IGOS Process Assess implementation of systems Evaluate usefulness of products International and national Scientific Social Economic and Political drivers Use Resul- tant Products Evaluate capabilities of Observational systems Assess Requirements for Observations Obtain commit- ments for change