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World Meteorological Organization Global Atmosphere Watch WORLD METEOROLOGICAL ORGANIZATION GLOBAL ATMOSPHERE WATCH No. 140 WMO/CEOS REPORT on a STRATEGY for INTEGRATING SATELLITE and GROUND-BASED OBSERVATIONS of OZONE JANUARY 2001 WORLD METEOROLOGICAL ORGANIZATION GLOBAL ATMOSPHERE WATCH No. 140 WMO/CEOS REPORT on a STRATEGY for INTEGRATING SATELLITE and GROUND-BASED OBSERVATIONS of OZONE WMO TD No. 1046 List of Contents Foreword ...................................................................................................................................... iii Executive Summary...................................................................................................................... v Milestones in the History of Ozone ............................................................................................ ix 1. Introduction.......................................................................................................................... 1 1.1 The IGOS Strategy ................................................................................................. 1 1.2 The Ozone Project.................................................................................................. 2 1.3 Requirements and Data Sources .......................................................................... 5 1.4 The Objectives of the Report ................................................................................ 9 2. User Requirements............................................................................................................ 11 2.1 Sources of Information and Definitions ............................................................. 11 2.2 Relationships between Applications and Requirements .................................. 13 2.3 The Requirements................................................................................................ 14 3. Available and Planned Measurements ............................................................................. 21 3.1 Introduction.......................................................................................................... 21 3.2 Non-Satellite Measurements ............................................................................... 21 3.3 Satellite Measurements ....................................................................................... 35 4. Harmonisation of Provisions and Requirements ............................................................ 47 4.1 Introduction.......................................................................................................... 47 4.2 Total Column Ozone ............................................................................................ 47 4.3 Ozone Vertical Profile.......................................................................................... 49 4.4 Meteorological Parameters ................................................................................. 51 4.5 Related Chemical Constituents .......................................................................... 54 5. Calibration and Validation................................................................................................. 57 5.1 Introduction.......................................................................................................... 57 5.2 Calibration and Validation Approach.................................................................. 58 5.3 Algorithms and Radiative Transfer..................................................................... 60 5.4 Ground-based Observations............................................................................... 60 5.5 Validation of Trace Gases ................................................................................... 64 5.6 Scientific Analyses............................................................................................... 65 5.7 Principles and Recommendations for Calibration and Validation ................... 66 5.8 Implementation Strategy ..................................................................................... 67 6. Recommendations............................................................................................................. 69 6.1 Introduction.......................................................................................................... 69 6.2 Algorithms and Calibration ................................................................................. 71 6.3 Implementation .................................................................................................... 72 6.4 Recommendations for Additional Space-Borne Measurements....................... 74 6.5 Advisory Body for the Ozone Project ................................................................. 75 6.6 Concluding Remarks ........................................................................................... 76 i Annex A: Lists of Scientists and Experts Consulted ............................................................. 77 Annex B: Tables of User Requirements .................................................................................. 81 Annex C: The Data Records of Regularly Reporting Ground-Based Ozone Stations........ 101 Annex D: Examples of Airborne Research Campaigns........................................................ 109 Annex E: Other Space-Based Instruments ........................................................................... 117 Annex F: Acronym/Abbreviation List .................................................................................... 125 ii iv EXECUTIVE SUMMARY Introduction CEOS and WMO recognize the need for better integration of the major satellite and ground-based systems to provide highly accurate, global environmental observation of the atmosphere, cryosphere, oceans and land in a cost effective fashion. To satisfy this objective, a framework for compiling user requirements, coupled with an overarching strategy for making global observations is the goal of the new IGOS (Integrated Global Observing Strategy), set up by a number of international bodies including WMO and Space Agencies. This report is a contribution to the international effort. It proposes the better integration of the various systems used to monitor ozone, including related key atmospheric parameters, and will contribute to the objectives of the IGOS within a general IGOS theme on atmospheric chemistry. This will assure the most effective use of available resources for global observations, although priorities must be established for upgrading existing and/or establishing new systems and provide a framework for decisions to ensure: • the long term continuity and spatial comprehensiveness of key observations • the research needed to improve understanding of Earth processes so that observations can be properly interpreted. The project will build upon existing and planned international global observation programmes (e.g. METOP, NPOESS, WMO-GAW and NDSC) and identify deficiencies in the current and planned systems. This report and its recommendations were compiled by a collection of clients, space agency representatives and a cross section of experts and specialist in atmospheric research. The list of contributors to this report and their institutions appears in Annex A The Ozone Project aims to develop the foundations of an integrated ozone measurement strategy. This strategy reflects the need to understand variations of ozone in the troposphere and stratosphere because of the central role the gas plays in several major environmental problems: • total column ozone is a controlling factor in determining levels of biologically damaging ultraviolet radiation reaching the Earth’s surface; • ozone is an oxidising pollutant that is harmful to humans, animals and vegetation and degrades man-made materials; • ozone is an active component of tropospheric and stratospheric photo-chemistry; • ozone is a “greenhouse” gas that contributes to the Earth’s radiative balance. The project covers primarily the observational requirements associated with the "Montreal" Protocol of the Vienna Convention. One of its specific objectives is to document the requirements for observations of ozone and associated parameters needed to properly interpret the ozone observations. These are then reviewed in the light of provisions for data acquisition with the focus on the observing community and the steps needed to meet user requirements. The project recognises the need and existence of appropriate numerical chemical and transport models used to interpret the observations. Grateful acknowledgement must be made to the many scientists and institutions (listed in Annex A) who have contributed to the production of this report both by participating in the workshops and by written contributions. Without this support the production of this report would not have been possible. v Requirements The Ozone Project has compiled a list of user requirements from the scientific community (WMO-GAW, SPARC, IGAC) and existing measurement programmes from space and the ground1 have been documented. From an analysis of the provisions and requirements, a set of recommendations for establishing an integrated global ozone observing system is proposed. This strategy distinguishes measurements that are needed continuously from those that are only needed occasionally. A well supported and on-going validation programme coupled with a data quality control programme is essential. As data sets improve, planning for the reprocessing and the distribution of data is a major objective. In addition to ozone itself,
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