1. Global Measurements and Research on Stratospheric Ozone Depletion For The Vienna Convention and Its Protocols: Users, Needs & Requirements Leonard A. Barrie C/ENV/AREP/WMO, Lbarrie@wmo.int

2. Vienna Convention History I The Stratosphere 1981: Theory and Measurements. WMO No. 11. 1985 Vienna Convention Atmospheric Ozone 1985. Three volumes. WMO No. 16. 1987 Montreal Protocol International Ozone Trends Panel Report 1988. Two volumes. WMO No. 18. Scientific Assessment of Stratospheric Ozone: 1989.Two volumes. WMO No. 20. 1990 London Adjustments andAmendment Scientific Assessment of Ozone Depletion: 1991. WMO No. 25.

3. Vienna Convention History II Methyl Bromide: Its Atmospheric Science, Technology, and Economics (Montreal Protocol Assessment Supplement) UNEP (1992). 1992 Copenhagen Adjustments and Amendment Scientific Assessment of Ozone Depletion: 1994. WMO No. 37. 1995 Vienna Adjustment 1997 Montreal Adjustments and Amendment Scientific Assessment of Ozone Depletion: 1998. WMO No. 44. 1999 Beijing Amendment Scientific Assessment of Ozone Depletion: 2002. WMO No. 47. 2003 15th Meeting of the Parties

4. Information Needs Of The Parties To The Convention: Assessment 2002 1.Trends in controlled substances and their consistency with reported production; 2.Impacts of new halogen-containing substances; 3.Methyl bromide sources and sinks and implications for the ozone layer; 4.Interrelations between ozone depletion and climate change including feed-backs between the two; 5.Changes in global and polar ozone and in ultraviolet radiation, as well as future projections and scenarios.

5. 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, history C.Satellite observations Global coverage, uniform data quality D.Chemical models and data assimilation tools Integration, data analysis and exploitation

6. 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.

7. ESTIMATED GLOBAL COLUMN OZONE 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 symbols represent different instrument types.

8. Courtesy of the World Data Centre for Greenhouse Gases JMA

9. Stratospheric O 3

10. Figure 4-4 in Ozone Assessment based on Fioletov et al 2002 QBO and Solar Effects estimated using ground-based data only

11. Future Needs Of The Parties To The Convention From 2002 Assessment I: 1.Is The Montreal Working? Observational Indicators: Downward Trends In Br and Cl ODS. Recovery of the Stratospheric Ozone (e.g. Antarctic O 3 full recovery predicted by 2050- assuming all other influences constant) 2.High Vulnerability of The O 3 Layer In The Next Decade; In 1992-2001 O 3 Depletion Relative To Pre-1980: Northern Mid-Latitudes: winter/spring 4%, summer 2% Southern Mid-Latitides: all year 6% {Corresponding change in erythemal radiation is 5, 2 amd 7%} Arctic ozone is highly variable estimates of winter/spring O 3 loss range up to 25%. Volcanic eruptions can add to losses  AEROSOL CONNECTION

13. Future Needs Of The Parties To The Convention From 2002 Assessment II: 3.Estimating Impacts Of Highly Variable Short-Lived ODSs which do not have a single global ODP. Integrated Observational Systems can help define the global temporal/spatial distribution. 4.Understanding The Ozone Depletion and Climate Change Connections: Long-lived spatially invariable CFCs are decreasing, while, shorter-lived, spatially variable HCFCs of similar GWP are increasing.

14. 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 researchers for environmental policy development and for improved weather/environmental prediction. To initiate a process leading to the implementation of globally coordinated observation and integration programmes within 10 years, by:

15. The 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 other key components of an integrated system (data processing and modelling);  Make recommendations and propose a structure for implementation.

16. 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

19. Target and Threshold Requirements for Aerosol

20. Integrated Global Atmospheric Chemistry Observation System (IGACO)

21. 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

22. Global Monitoring: a Complex Task Requiring Central Coordination

23. Stratospheric Aerosols