The passing of two decades since the inception of the Montreal Protocol has provided scientific proof of the treaty's effectiveness and truly deserves the title of the most successful environmental treaty to date. Having phased out 95 percent of the ozone-depleting substances covered in the treaty, the Montreal Protocol has not only allowed the ozone hole to begin the healing process, but as scientists have recently discovered, the treaty has also been an incredibly effective measure in mitigating climate change. Phasing out harmful ozone substances that double as deadly greenhouse gases has delayed climate forcing by 35-41 years.

In the following chapters, new information on the effects of increased UV radiation will be discussed in more detail, with special attention given to the role of interactions between ozone depletion and climate change.

This Handbook, which updates the 2000 edition, incorporates all the adjustments, amendments and the decisions of the Parties up to the end of 2002. In addition, it gives valuable information on the implementation of these international environmental treaties. In this single volume, anyone interested in the issue can find the details of legal and policy actions taken by the world community to protect the ozone layer.

Developed by the UNEP DTIE OzonAction Programme with input from the Ozone Secretariat, the Multilateral Fund Secretariat, National Ozonne offiers and Methyl bromide experts from the public and private sectors I developed and developing countries, this handbook provides the key methyl bromide data reporting information. It was developed as part of UNEP's Work Programme under the Multilateral Fund for the Implementation of the Montreal Protocol.

This Handbook is part of a series of publications designed to assist developing countries to develop, implement and enforce policies required for compliance with the Montreal Protocol. Each of these documents has been developed in co-operation with internationally renowed organizations with specific policy expertise.

Subsequent Meetings of the Parties to the Montreal Protocol have taken a number of decisions, which request actions by the UNEP Technology and Economic Assessment Panel (TEAP). Responses of the TEAP to several of the 2002 requests, as well as responses to requests made in earlier Meetings of the Parties, are presented in this May 2003 report.

This report is the response by the Technology and Economic Assessment Panel to Desision XI/28 of the Eleventh Meeting of the Parties to the Montreal Protocol in Beijing 1999.

The present document contains key summaries from the Scientific Assessment of Ozone Depletion : 2002. The full assessment report will be part of the information upon which the Parties to the United Nations Montreal Protocol will base their future decisions regarding protection of the stratospheric ozone layer.

To help foster a continued interaction, this component of the Scientific Assessment of Ozone Depletion : 2002 presents 20 questions and answers about the often complex science of ozone depletion. The questions address the nature of atmospheric ozone, the chemicals that cause ozone depletion, how global and polar ozone depletion occur, and what could lie ahead for the ozone layer.

The Methyl Bromide Technical Options Committee (MBTOC) was established by the Parties on the Montreal Protocol on Substances that Deplete the Ozone Layer to identify existing and potential alternatives to methyl bromide (MB). This Committee, in particular, addresses the technical feasibility of chemical and non-chemical alternatives for the current uses of MB, apart from its use as a chemical feedstock.

In 1981, in response to the growing scientific consensus that chlorofluorocarbons (CFCs) and halons would deplete the ozone layer, the United Nations Environment Programme (UNEP) began negotiations to develop multilateral protectionof the ozone layer. These negotiations resulted in the Vienna Convention for the Protection of the Ozone Layer, adopted in March 1985. The Convention provided a framework for international co-operation in research, environmental monitoring and information exchange.

The following sector summaries show the remarkable progress that has been made to significantly reduce the need for halons and discuss the current state of cooperative or individual arrangements to ensure adequate stocks of halons to meet future needs.

In the last decade, the refrigeration, air conditioning and heat pump industry made tremendous technical progress and complied with the Montreal Protocol through phasing out CFCs and in several applications, HCFCs as well. The mobile air conditioning and the demestic refrigeration industries have shifted rapidly from CFC-12 to non-ODS refrigerants. Other applications, such as chillers and commercial refrigeration, have shifted from CFCs to HCFCs and HFCs or other fluids.

The 2002 report is considerably different form the previous reports of the Solvents Technical Options Committee (STOC). The physical structure has been designed so that each sub-sector has a self-contained chater that summarises new, essential, information and the technology choices available. it is intended that these individual chapters may be extracted for copying to interested parties, while remaining short enough for translation into local languages and subsequently distributed.

Eight examples describing how countries and organizations have approached and addressed different aspects of halon management. The topics range from the adoption of alternatives in different sectors (aviation, electronic facilities, military) to how a country organized a network of stakeholders and institutions to steer the halon phase out (Poland) to the experience of specific organizations in different aspects of halon management (NASA, Alang shipbreaking yard) and decommissioning halon systems.

This easy-to-use compact reference system provides essential resource material related to industry's response to the Montreal Protocol. The case studies included on this CD-ROM, not only show the success of the treaty, but also different companies' efforts to develop reliable alternatives to Ozone Depleting Substances (ODS). Although specifically developed to assist National Ozone Units and industry in developing countries, this CD-ROM is useful to anyone interested in the Montreal Protocol and the phase-out of ODS.

This report considers CFC uses in aerosol products, as sterilants and in a range of miscellaneous applicatoins including food freezing, tobacco expansion, fumigation and cancer therapy. It also covers the use of carbon tetrachloride.