As a climate negotiator in the early 1990s I have a strong recollection of the impact of Professor Bolin's statements to the International Negotiating Committee for the Framework Convention on Climate Change. When the chairman of the Intergovernmental Panel on Climate Change (IPCC) presented its findings there was silence in the room: here were the facts, the certainties and the uncertainties.

We were all part of a process in which national interests and national instructions governed our actions and limited the rate of progress. We were all painfully aware of this, and we were also on a learning curve. As diplomats and generalists, most of us had limited knowledge of the substantial issues of climate change, but here we had the opportunity to listen to one of the most prestigious experts, speaking in clear language, devoid of academic jargon. Furthermore, we realised that Bert Bolin, as a former scientific adviser in the Swedish Prime Minister's office, had a thorough knowledge of the political process, its possibilities and limitations.

All this enabled him to set high standards for the work of the IPCC from the beginning, creating a scientific backstop to the negotiations which in my view has had a decisive impact on the relative success of the process. The IPCC is not only a venue for interdisciplinary science, it is also a meeting-place for researchers and Government officials, thereby facilitating the inevitable process of multilateral bargaining on the terms of legally binding international instruments.

The post-Second Assessment Report discussions of an action programme to be agreed in Kyoto

The year 1995 ended with the completion of the SAR at the eleventh IPCC session in Rome. Earlier in the year the Climate Convention had formulated a mandate in Berlin for negotiations to be conducted during 1996 and 1997 in order to arrive at decisions on actions to be taken at the third conference of the parties at Kyoto. But the journey that awaited the IPCC during the next two years was not to be a smooth one. Even though the scientists that had been involved with the IPCC supported the conclusions that had been drawn, there was not complete unanimity in the scientific community about all that the IPCC had concluded, which of course was no surprise. Scientific progress is always based on challenging current knowledge. In addition stakeholders organised themselves in order to protect their conceived economic interests. The IPCC bulk reports exposed the uncertainties and disagreements as well as possible wherever they appeared, and the summaries for policy makers expressed these conclusions carefully in order not to give a false impression of certainty, where there was uncertainty. The paragraph that summarised our understanding of the degree of human interference with the climate system may be taken as an example. It was concluded, fully recognising the uncertainty in a caveat (see Section 8.2.1), that ‘… the balance of evidence suggests that there is a discernible human influence on global climate.’

Work towards the IPCC Third Assessment Report

The eleventh plenary session of the IPCC in the Maldives in October 1997 and the third conference of the parties to the Climate Convention in Kyoto in December that same year were my last engagements as chairman of the IPCC. Since then I have followed the IPCC work attentively but at a distance, have taken part in the work on IPCC's Special Report on Land Use, Land-Use Change, and Forestry, and been one of the review editors of The Scientific Basis of the Third IPCC Assessment Report published in 2001. Obviously, I have not been in a position to follow the internal work and controversies as closely as during my time as chairman of the IPCC. Nonetheless the following observations might be of interest.

First, five major special reports were completed during 1998–2001.

• Analyses of the regional impacts of climate change (IPCC, 1998). In addition to this work by the IPCC, a large number of other analyses have of course been carried out at national level. This is not, however, the place to expand on this essential work.

• […]

Initiation of assessments aimed at politicians and society

The first efforts to analyse climate change as a threat to humankind more specifically were made in the USA. Undoubtedly, the USA was leading the development of global climate models, particularly through the work at the Geophysical Fluid Dynamics Laboratory at Princeton, NJ, and towards the end of the 1970s some interest could be observed outside the expert groups. This was partly the result of a book published by one of the participants of the SMIC conference in Stockholm 1971 (see Schneider (1976)). Similar initiatives were not common elsewhere.

There was, however, also an early interest in Sweden because of my own involvement in global environmental issues (Bolin, 1976). I was asked by the Swedish Government in 1975 to summarise available knowledge, and later that same year it was concluded in a government bill concerning future Swedish energy policy that ‘… It is likely that climatic concerns will limit the burning of fossil fuels rather than the size of the natural resources.’

An early assessment of available knowledge regarding possible future human-induced changes of climate with the specific aim of informing a wider scientific audience was initiated by the US NAS (1977). This detailed and carefully prepared overview of the state of knowledge and recommendations for intensified research served as a basis for the US efforts for a number of years.

First party conference of the FCCC

It is important first of all to make clear that the Climate Convention that came into force in 1994 is a framework convention that primarily specifies the procedures to follow and agreements on the general structure of the intergovernmental arrangements required in order to deal with the climate change issue. It does not specify any quantitative and binding commitments for the parties, but regulates the important matter of establishing a reporting system between countries and the Convention secretariat. Two prime tasks for the first conference of the parties in Berlin in March–April 1995 were accordingly to elect chairpersons and members of committees to be set up, and to formulate the goals for the negotiations between countries during the next few years, i.e. the ‘Berlin mandate’. As chairman of the IPCC I was also anxious to get a clear idea about the forthcoming interplay between the IPCC and the SBSTA which was to be formed by the Convention.

The upcoming first conference of the parties stimulated discussion in wider circles of the assessments carried out so far by the IPCC, and the process for the assessment that IPCC had developed. There would obviously be more publicity about the climate change issue and also the IPCC during coming months. I was going to give a presentation at the UN at the beginning of February and it was decided that I would then spend a few days in Washington DC, and thereby become more acquainted with representatives of the US press.

Work begins

The IPCC had been formed and its task for the next 18 months had been agreed. Time was short for the completion of a full assessment. The work had to be done in a new setting and involve many people who had not previously been engaged in such activities. Measures had to be taken to structure the work and to ensure broad participation by key scientists. The three working groups scheduled meetings for the early months of 1989. Outlines of their reports were agreed, lead authors for the individual chapters selected and workshops on key topics scheduled.

The fact that the issue of climate change had been brought to the attention of the UN General Assembly implicitly meant recognition of the importance of the climate change issue and also of the IPCC itself. This became obvious at the first meeting of Working Group III in Washington in January 1989 (see IPCC (1989a)). The newly appointed US Secretary of State, James Baker, gave his very first public speech in his new position at the opening of this meeting. The majority of those attending were not scientists. There were five members of US Congress and some 25 delegates from government ministries and agencies. This was not the composition of the audience that I had imagined. It is interesting to recall a few key issues that were brought forward on this occasion.

Secretary Baker applauded the recognition of environmental problems as a transnational issue.

The importance of trustworthy scientific knowledge in climate negotiations

As a scientist, I have been engaged in the interplay between scientific analysis and politics for many years, and I have tried here to present an analysis of what has happened over the last 40 years and where we stand today.

The analysis has shown that a penetrating examination of the facts is an absolute necessity when trying to understand and deal with the major societal and political issues that confront us when we try to resolve the global climate change issue. The analyses must be accepted as trustworthy by the international scientific community and should therefore be carried out as far as possible as an independent and open scientific endeavour. The IPCC reports have been produced in a manner aimed at securing this status. They have largely been free from influence by politicians and stakeholders of different kinds. Nevertheless, government representatives have attended the final plenary sessions, when the summaries for policy makers were finally agreed and the extracts of the key scientific conclusions formulated in simple terms without compromising the basic scientific analyses in the supporting documents. This is a fundamental prerequisite for successful climate negotiations, and decisions about the joint efforts to be made by the parties to the Climate Convention. The development of a strict procedure of the kind that has been achieved by the IPCC has been essential and has also been taken as a model for other efforts of a similar kind.

The report by the UN Commission on Environment and Development

The year was 1987. The autumn had come and the UN General Assembly had opened in New York. As described in the previous chapter the UN Commission on Environment and Development under the chairmanship of Gro Harlem Brundtland (Norway) had completed its report, Our Common Future, and it was about to be discussed in the General Assembly.

The report painted in broad strokes a picture of a rapidly changing world and an increasing exploitation of natural resources. It referred to successes in dealing with the global issues of development:

But at the same time it was recognised, that

Changes in the IPCC structure and new members of the Bureau

The IPCC had implicitly been given a clear task by the large number of countries that signed the FCCC in Rio: i.e. to continue the assessments and serve the INC in its work towards a first meeting with the parties of the Convention that might take place within the next few years. Signatures from only 50 countries were needed for the convention to come into force. Our understanding of the environmental aspects of the issue now needed to be broadened and a more penetrating assessment was needed of the impacts of a climate change and its associated costs, together with socio-economic studies of the implications of mitigation and adaptation. But whenever value judgements were an essential part of such issues, care had to be exercised in order to avoid criticism of the IPCC efforts because of possible implicit political assumptions in the course of the analyses.

As was pointed out in Section 6.5, it was for the IPCC to judge how the expression dangerous interference with the climate system should be interpreted, but it was of course still important that relevant information was provided to serve as a basis for political analyses and negotiations. This was more important now, when industries were gradually becoming aware of the possible threats to their activities, which was how many of their representatives viewed the emerging situation.

The general setting

The early eagerness amongst politicians around 1990 to act in response to the threat of a human-induced climate change was largely genuine and in line with the increasing general attention that was given to environmental issues during much of the 1990s. There was, however, early reluctance from industry and other stakeholders to proceed quickly. They feared that action to protect the current climate, i.e. a reduction in the use of fossil fuels, might be a threat to their activities and admittedly the scientific basis for taking action was then hardly convincing.

Other major global issues, particularly many of a political nature, have since been brought into focus and have greatly influenced world politics, especially since the turn of the century. The conflicts in the Middle East to some considerable degree stem from a realisation that the global energy supply system might have to change during the coming decades. The conventional reserves of oil will dwindle within a decade or two and natural gas will begin to run out towards the middle of the century, while the global demand for energy will be increasing quickly, not least because of the rapid industrialisation in developing countries.

There is a need for trustworthy scientific information in order to find a common strategy between, on one hand, those that are giving priority to the short-term political security in today's society and, on the other, those that are anxious to safeguard the global environment and obtain a sustainable development emphasising the long-term issues.

Glimpses of the historical development of our knowledge

Carbon is the basic element of life. All organic compounds in nature contain carbon and the carbon dioxide in the atmosphere is the source of the carbon that plants assimilate in the process of photosynthesis. An understanding of the global carbon cycle is of basic importance in studies of human-induced climate change, not only because of the need to determine expected changes of atmospheric carbon dioxide concentrations due to human emission, but because natural changes of the carbon cycle may also have influenced the climate in the past.

The detection of the fundamental chemical and biochemical processes of relevance in this context is a most important part of the development of chemistry during the eighteenth century and the first decades of the nineteenth century. Joseph Black (1754) is credited with the discovery of carbon dioxide gas. Its real nature was, however, not very well understood until Carl W. Scheele in Sweden and Joseph Priestley in England identified ‘fire air’ (i.e. oxygen) a few decades later and the French chemist Lavoisier correctly interpreted the concepts of fire and combustion. When carbon burns, carbon dioxide is formed.

It was not realised until well into the nineteenth century that carbon dioxide, like oxygen and nitrogen, is a permanent constituent of the air and that it is a source of carbon for plants. However, it was not then possible to measure the amount present in the atmosphere.

Building scientific networks

The formative years

On 1 April 1960 the USA launched its first meteorological satellite, TIROS 1. It was a remarkable experience for people to be able to view the earth and its atmosphere from the outside. The bluish colour of our planet fascinated observers and a number of well-known features of the circulation of the atmosphere became visible through the cloud formations that they create. Most of what one could see was familiar to the meteorologists. It appeared so consistent with the knowledge that had been taught in basic courses for years. Nevertheless, another dimension had been added. A very effective new tool for observing the weather had become available. The weather services were soon engaged in trying to find out how this new information could best be exploited. Scientists sensed that a new era in meteorology and climatology had begun.

The event was also of profound political importance. A satellite had been launched that might be used internationally for peaceful purposes. Had a new opportunity thereby been opened in the race between the USA and the USSR to be in the lead in space? Would this indeed be the beginning of peaceful global cooperation? President J. F. Kennedy seized the opportunity. In an address to the General Assembly of the United Nations (UN) in 1961 he called on the countries of the world to exploit this new tool jointly.

Delayed action in spite of trustworthy scientific assessments

Mitigating climate change is finding ways and means to reduce emissions to the atmosphere and to enhance sinks for the atmospheric components that disturb the radiative balance of the earth with space. But it is equally important that this should be done in a way that minimises costs and the degree of disturbance to countries and people, ensures a sustainable development and is in this sense politically acceptable. The issue is thus not primarily a technical and economical one, but societal and political, even though technical and economic analyses of the means to deal with it are very important as a basis for identifying and reaching agreements on action plans and how they are to be implemented. A brief overview of matters that are of prime concern in this context will be given in this concluding chapter, especially with regard to the basic scientific and technical knowledge about the global society that will be required. The best common understanding of this issue is a prerequisite in order to mitigate a human-induced climate change quickly enough. This is, however, not the place to analyse the technically complex issue of alternative future global energy systems in detail.

Stabilising the global climate must necessarily be a worldwide cooperative undertaking, but it is important to recognise countries' differing ability to contribute. This is well expressed in the Climate Convention.