The Stockholm Conference on the Human Environment in 1972 named the environmental assessment component of its action plan "Earthwatch" and recommended that environmental assessment to be one of the basic operational areas of the UN Environment Programme. 

The UN General Assembly in its resolution 2997 (XXIIV) Institutional and Financial Arrangements for international environmental co-operation, endorsed the Stockholm recommendations and set up UNEP. It further decided to establish a Governing Council of UNEP which will have among other the following functions and responsibilities: 

- Keep under review the world environmental situation in order to ensure that emerging environmental problems of wide international significance receive appropriate and adequate consideration by Governments; 

- To promote the contribution of the relevant international scientific and other professional communities to the acquisition, assessment and exchange of environmental knowledge and information and, as appropriate, to the technical aspects of the formulation and implementation of environmental programmes within the United Nations system. 

GC Decision l (l) of 22 June 1973 decided that one of the major functional tasks of the Programme consists of the identification and assessment of the major environmental problems for which "Earthwatch" will be one of the important instruments. 

GC decision 8 (II) of 22 March 1974 authorizes the Executive Director to design, develop and begin to implement the Global Environment Monitoring System (GEMS) and the International Referral System within the Earthwatch cluster. 

GC Decision 29 (III) of 2 May 1975 requested the Executive Director to give high priority to the consolidated development and improvement of Earthwatch, which consists of research, evaluation, monitoring and information exchange activities, to treat all these components both functionally, in terms of an integrated system, and programmatically as part of each priority subject area which they serve. It also authorized the Executive Director to establish a programme activity centre for the International Register of Potentially Toxic Chemicals, to serve as an essential tool in optimizing the use of chemicals for human well-being while at the same time providing a global early warning system of undesirable environmental side effects of potentially toxic chemicals. 

"Earthwatch" was subsequently defined in document UNEP/GC/61 considered by the 4th Session of the Governing Council as a "dynamic process of integrated environmental assessments by which relevant environmental issues are identified and necessary data are gathered and evaluated to provide a basis of information and understanding for effective environmental management". 

GC Decision 63 (IV) of 13 April 1976 recognized the major importance of Earthwatch to the achievement of the objectives of the United Nations Environment Programme and requested the Executive Director to develop and initiate the implementation of an integrated evaluation programme and interdisciplinary research programme as interacting component parts of Earthwatch, along with the Global Environmental Monitoring System, the International Referral System and the International Register of Potentially Toxic Chemicals. 

The conceptual approach and operational sequences of environmental assessments have been outlined and the elements of comprehensive assessments of any selected environmental problem have been formulated by different expert groups convened by UNEP. It has been realized that comprehensive assessments at the international level can only be obtained in a selected number of cases where sufficient information exists. Even at the national level comprehensive assessments have been hampered by lack of information or the integration of information. It was agreed that the Earthwatch process ought to be iterative, i.e., that assessments on a particular topic of importance should be made at regular intervals depending upon monitoring data and research knowledge becoming available as well as upon political circumstances. Thus it is then possible to follow environmental change with time, establish the trends in such changes, and to obtain an indication and understanding of the causes of these trends. 

This approach was applied from the beginning to critical problems as they were identified. For instance, upon the scientific disclosure in 1974-75 that the chlorofluorocarbons emitted into the atmosphere could endanger the stratospheric ozone layer, UNEP convened in 1977 an international expert meeting to discuss which mitigating activities should be undertaken under Earthwatch. Arising from the decisions of this conference the Co-ordinating Committee on the Ozone Layer was created under the Chairmanship of the Director of Environment Assessment in UNEP. This Committee from 1979 to 1985 was in charge of a continuously progressing assessment process where every year a report on findings in the area was published and where a comprehensive assessment report was issued in 1985. This assessment process lead to a governmental negotiating process for a convention on the ozone layer which was adopted in Vienna in 1985, followed by the Montreal Protocol on ozone-depleting substances in 1987, which was further strengthened in 1990 following new evidence of accelerating damage to the ozone layer. The ozone depletion issue is a successful example of the Earthwatch process. 

Similar monitoring and assessment activities were set up or strengthened by various agencies with support from UNEP in other sectors such as background air pollution, oceans and coastal areas, hazardous wastes and toxic chemicals, climate change, food contamination, forest resources, freshwater resources and water quality, etc. 

The Seventh Session of the Governing Council of UNEP in 1979 established an ad hoc Group of Government designated Experts to "consult on the development of mechanisms and procedures for conducting environmental assessment within Earthwatch." In its report the Group of Government designated Experts endorsed the general approach to Earthwatch that had existed since 1972 and formulated in detail the elements of comprehensive assessment of any selected environmental problem. 

In order to study and further develop the activities involved with Earthwatch, UNEP in cooperation with relevant UN agencies and organizations in 1981 made an in depth review of Earthwatch as a UN system-wide concept. The review refers to the original concept of "Earthwatch" from the Stockholm Conference and summarizes Earthwatch development up to 1981. Systematic methods for identification and selection of topics and problem areas for assessment were considered and agreement was reached on a variety of activities to be used in order to encourage the carrying out of assessments at national, regional and global levels as well as for developing suitable assessments. Types of activities which have since been used in the Earthwatch process include: 

- surveys of monitoring network data and of information contained in the literature, 
- government-designated expert meetings and expert consultations, 
- consultancies at the request of national governments, 
- support for national, regional and global monitoring and assessment projects, 
- development of monitoring and assessment methodologies, 
- co-ordination of international quality assurance programmes, 
- collection, compilation, analysis, dissemination and exchange of information, 
- production of environmental data tables and summaries, 
- national and regional training courses, 
- co-ordination of international monitoring networks etc, 
- establishment of global regional and national data centres, 
- production of topic-specific assessment reports. 

Within the UNEP Secretariat all the above categories of Earthwatch activities are carried out to different degrees by those programmes activity centres which constitute the environmental assessment process, GEMS/GRID, INFOTERRA and IRPTC and by other UNEP units such as OCA/PAC, Environmental Management and the State of the Environment Unit. 

In 1981 the concept of the System Wide Medium-term Environment Programme was adopted as a process for joint planning of environmental activities within the UN system. The first SWMTEP report for the years 1984-89 was adopted by GC Decision 10/13 of 31 May 1982. 

At its 1982 Session of Special Character, the GC reviewed the major achievements in the implementation of the Action Plan for the Human Environment adopted by the Stockholm Conference in 1972. In relation to the area of Environmental Assessment, the Council stated that: 

- The Global Environment Monitoring System is operating and expanding, although important gaps in the development, co-ordination, user applications and integration of the system components persists; 

- The Global Atmospheric Research Programme has continued and international studies of climatic change and variability and of the applications of climate knowledge to human activity have been incorporated in the World Climate Programme. 

- The International Referral System for sources of environmental information is functioning but has not adequately realized its objectives, in particular because the growth of user demand has been slow; 

- The International Register of Potentially Toxic Chemicals has started to prove itself as an important centre for information on toxic chemicals; 

- The International Programme on Chemical Safety is providing toxicological assessments for an increasing number of substances, together with accelerated manpower development, guidelines for emerging response to chemical accidents and technical co-operation relating to control of toxic chemicals; 

- Assessments of the environmental impacts of various sources of energy have been published; 

- A major report entitled The World Environment 1972-1982 has been published in conjunction with the session of special character. 

The Council decided that the basic orientation of the Programme in the area of Assessment for 1982-1992 would be: 

- To improve early warning indicators of significant environmental changes; 

- To improve the planning and co-ordination of monitoring at the global and regional levels; 

- To produce concrete assessment statements for important environmental problems and their human health, social and economic implications; 

- To establish better links between the Global Environment Monitoring System, the International Referral System for sources of environmental information, the International Register for Potentially Toxic Chemicals and national and International data centres;

- To promote the establishment of reliable global, regional and national environmental statistics and state of the environment reporting as a basis for evaluating major trends and deciding on any necessary action. 

GC Decision 14/13 adopted the Environmental Perspective to the Year 2000 and beyond which was subsequently adopted by GA resolution 42/186 of 11December 1987. One of the instruments of environmental action of the Perspective is Assessment which will have the functions of co-ordinating the collection of reliable information, analysing this environmental information and make it available to planners and managers in an usable form. The decision also reiterated that one of the major priority functions of UNEP should continue to be to monitor, assess and report regularly on the state of the environment and natural resources and emerging environmental issues. 

In 1988, GC in its first Special Session adopted the System-wide medium term environmental programme for the period 1990-1995, recognizing that SWMTEP is a valuable mechanism for the co-ordination of environmental activities within the United Nations system. 

In the realm of Earthwatch, SWMTEP has two general objectives: 

- To accumulate and improve reliable and comparable scientific and technical information about environmental issues and to develop and apply means of collecting, storing, retrieving and processing such information that will make it readily available to decision makers and specialists; 

- To provide comprehensive assessments of environmental issues on the basis of socio-economic data and data on the major components and processes of the global and regional environments, to monitor, in an appropriate way, the transition towards sustainable development. 

General Assembly resolution 45/253 of December 1990 adopted the medium term plan of the United Nations for the period 1992-1997. The Medium Term Plan considers that the global environment programme, Earthwatch, conceived in 1972 at Stockholm, is one of the main pillars of the Action Plan for the Human Environment. 

For nearly two decades, the elements of Earthwatch have been carefully assembled through data collection and assessment mechanisms in an increasing number of sectoral areas, generally developed by the UN specialized agencies in their areas of interest, often with the support and cooperation of UNEP. However, as the scale and magnitude of human impacts on the global environment became more apparent, it was clear that something more was needed to assemble all these parts together, to understand their interactions and their relations to the development process, and to evolve effective means of providing early warning of major problems. 

In December 1989 the United Nations General Assembly adopted resolution 44/224 on "International co-operation in the monitoring, assessment and anticipation of environmental threats and in assistance in cases of environmental emergencies". 

In this resolution the General Assembly noted with appreciation the work undertaken by the United Nations Environment Programme to develop criteria for the identification of environmental threats at the national, regional and global level. It also affirmed the need for closer cooperation between the United Nations Environment Programme, the Office of the United Nations Disaster Relief Coordinator, the World Health Organization and the World Meteorological Organization, as well as other competent organs, programmes and agencies of the United Nations system, bearing in mind the coordinating role of the United Nations Environment Programme in environmental matters in the United Nations system. 

The resolution underlined the importance of broader participation in Earthwatch, established by the United Nations Conference on the Human Environment and operated by the United Nations Environment Programme, in order to strengthen its capacity to make authoritative assessments, to anticipate environmental degradation and to issue early warnings to the international community. 

The resolution further requested the Secretary-General, assisted by the Executive Director of the United Nations Environment Programme to prepare a report, on the basis of the views of Member States and existing national and international legislation in this field, containing proposals and recommendations on possible ways and means to strengthen the capacity of the United Nations: 

(a) To monitor, assess and anticipate those threats; 

(b) To define criteria for determining when environmental degradation undermines health, well-being, development prospects and the very survival of life on the planet to such an extent that international cooperation may be required, if requested; 

(c) To issue early warnings to the international community when such degradation becomes imminent; 

(d) To facilitate intergovernmental cooperation in monitoring, assessing and anticipating environmental threats; 

(e) To assist Governments facing environmental emergencies, at their request; 

(f) To mobilize financial resources and technical cooperation to fulfil the above tasks, taking into account the needs of the countries concerned, particularly the developing countries. 

Finally, the resolution also requested the Secretary-General to submit to the Governing Council of the United Nations Environment Programme the above report for consideration during the preparatory process for the United Nations Conference on Environment and Development (UNCED). 

To advance these aims, an exploratory meeting was convened by the Executive Director of the United Nations Environment Programme on 18-19 July, 1990 in Geneva. The meeting recognised that the heart of Earthwatch should be the establishment of a well-defined monitoring and assessment programme. It reiterated that no single agency could cope alone with this vast topic, and that the response had to be system-wide, bringing in the work of all UN agencies and organizations. A small consultant task team then visited the main agencies active in theenvironmental field to ascertain their relevant actions and potential roles and to prepare a report on
how to further develop Earthwatch paying particular attention to early warning and forecasting needs. A second meeting was held in February 1991 to draft appropriate proposals for the future of Earthwatch. The resulting draft report was sent to the Heads of Agencies for comments, finalized and presented to the Governing Council, which requested that it be brought to the attention of the General Assembly. The General Assembly, in turn, in its resolution 46/217, noted the report and asked that it be conveyed to the Preparatory Committee of UNCED. 

The Governing Council, in its decision 16/37 on early warning and forecasting of environmental emergencies, considered that assessments are particularly needed in all those concentration areas which it had identified in its decision 15/1, and enumerated by the General Assembly for consideration of the United Nations Conference on Environment andDevelopment (in resolution 44/228 of 22 December 1989). Earthwatch should also be able to accommodate emerging issues as and when the need arises. The Governing Council recommended that Earthwatch, in keeping with its mandate, should identify global and regional environmental monitoring and assessment needs, co-ordinate and harmonize global, regional and national monitoring and assessment programmes to the extent required, prepare comprehensive assessment statements, inventories and analytical statements, give advanced warning of emerging environmental threats, advise on causal relationships of observed environmental changes, and suggest policy responses and management
options where necessary. It further recommended that Earthwatch should pay particular attention to the interface between environment and development. It requested the Executive director to continue to strengthen the environmental monitoring and assessment capacities of developing countries to enable them to participate actively and more fully in Earthwatch, and to prepare detailed proposals for ensuring adequate financial and institutional support to enable Earthwatch to
carry out fully its mandated programmes, to be considered at its next regular session in 1992. 

To strengthen the co-ordination of Earthwatch, UNEP named a high-level Co-ordinator and Deputy Co-ordinator of Earthwatch in late 1991, approved a project for the co-ordination of the Earthwatch programme, and initiated consultations with all the concerned agencies and organizations of the UN system on the mechanisms for the full implementation of the Earthwatch concept, including the re-establishment of the Interagency Working Group on Earthwatch and the creation of an Earthwatch Secretariat to provide a focus for action. 

The United Nations Conference on Environment and Development (the "Earth Summit") held in Rio de Janeiro in June 1992 adopted Agenda 21 as an action plan into the next century. Agenda 21 includes a chapter on Information for Decision-making and emphasizes in several places the need to strengthen Earthwatch as an essential component in process of assembling information on the environment, relating it to development information to determine what is sustainable development, and delivering it to the decision-makers who must decide on the course of our civilization. 

Earthwatch, as a process building on the capacity of the whole UN system to collect, evaluate and communicate information on the state of and trends in the global environment, is now taking a concrete and practical form, which should bring to fruition the vision Governments had in Stockholm twenty years ago.