History: ICSU and climate change

In recent decades, climate science has required international collaboration among researchers on an unprecedented scale, coupled with collaboration at the intergovernmental level. ICSU’s contribution has been crucial to defining the scientific issues, facilitating consensus on research priorities and convening collaborations which have underpinned the research. In parallel, ICSU has also worked tirelessly to initiate and support mechanisms for ground-breaking climate research to reach policy-makers in some cases resulting in important shifts in policy development.

Until the mid-1950s, international cooperation among scientists in diverse fields with an interest in climate was quite limited. An opportunity to scale up this cooperation emerged with the ICSU-initiated International Geophysical Year (IGY) in 1957–58, which brought together scientists from more than 60 countries to take part in a series of coordinated observations of geophysical phenomena. While greenhouse gases were not its key priority, the IGY provided funding to initiate the systematic measurements of atmospheric carbon dioxide (CO2). This work was carried out by Charles David Keeling at a base on Mauna Loa in Hawaii. In 1961, Keeling produced data showing that carbon dioxide levels were rising steadily on what became known as the “Keeling Curve”.

Following the success of IGY, the United Nations General Assembly formally invited ICSU to work alongside the World Meteorological Organization (WMO) in developing a programme of research on atmospheric science. ICSU and WMO appointed a committee to plan a new research programme which became the Global Atmospheric Research Programme (GARP) in 1967. The goal was to understand the predictability of the atmosphere and extend the time range of daily weather forecasts to more than two weeks.

One of GARP’s major achievements was its early recognition of the new science that could be done with satellites for continuous, global observation of the Earth and with computers for modelling global atmosphere circulation. In the 1970s, it produced several visionary collaborative experiments and results, notably the GARP Atlantic Tropical Experiment (GATE) in 1974. GATE delivered new insights into the ways in which tropical weather systems are organized and their links with overall tropical circulation and variations in surface temperature and other properties of the ocean. The Atlantic Tropical Experiment led to the highly successful Global Weather Experiment in 1979, involving over 140 countries, which laid the scientific foundation for redesign of WMO’s operational World Weather Watch. GARP, together with several other initiatives, drove the development of the climate science agenda.

In 1978, ICSU, the WMO and the United Nations Environment Programme (UNEP) organized an International Workshop on Climate Issues in Laxenburg near Vienna, where the participants planned a pioneering World Climate Conference for 1979. Their mode of organization was crucial, setting a standard for many later efforts. Participation was by invitation, mostly scientists and some government officials. The conference organizers commissioned a set of review papers inspecting the state of climate science. These were circulated, discussed, and revised. Then over 300 experts from more than 50 countries came to Geneva in 1979, examined the scientific evidence, confirmed the long-term significance of atmospheric CO2 levels for global climate and called for the establishment of a climate programme in its own right.

Government representatives in WMO and the scientific leadership of ICSU heeded the advice and in 1979 launched a World Climate Programme (WCP) with various branches, including the World Climate Research Programme (WCRP), which was the successor to GARP. WCRP has the broad objectives of determining how far climate can be predicted and the extent of human influence on climate.

Over the decades, WCRP established a ground-breaking programme of international and interdisciplinary research that has produced some major advances in climate science. Notable achievements include establishing the physical basis for understanding and predicting El Niño events, improved climate models as the basis for research and international assessments, and comprehensive field measurements and the development of regional and global observational climatic data sets leading to improved understanding of key climate processes.

In 1985, ICSU, together with WMO and UNEP, organized a major conference on the “Assessment of the Role of Carbon Dioxide and of Other Greenhouse Gases in Climate Variations and Associated Impacts” in Villach (Austria). Scientists at this conference agreed that greenhouse gases could warm the earth by several degrees, with serious consequences. The group’s scientific findings were summarized by the ICSU-initiated Scientific Committee on Problems of the Environment (SCOPE) in a seminal report “The greenhouse effect, climatic change and ecosystems”. This was the first comprehensive international assessment of the environmental impact of atmospheric greenhouse gases. The SCOPE report, together with the Villach conference, was the first to state that “substantial warming” would occur as a result of a doubling of CO2, to note that increases in CO2 “were attributable to human activities”, to recommend a variety of specific policy actions, and to urge more significant steps toward international cooperation on issues of climate change, calling for governments to recognize that future climate change could be stemmed by attention to policies concerning fossil fuel use, energy conservation and greenhouse gas emissions. The report called on governments to consider positive actions, even a “global convention” to prevent too much global warming. Climate science, in short, was no longer just a matter for scientists. The SCOPE report also shaped the recommendations of the 1987 Brundtland Report “Our Common Future” on action to protect the earth’s climate.

The Villach conference called for ICSU, WMO, and UNEP to establish a task force on greenhouse gases and to ensure that periodic scientific assessment was undertaken. This led to creation of an Advisory Group on Greenhouse Gases (AGGG), appointed by ICSU/WMO/UNEP. This group organized international workshops and produced several reports on the policy implications of the emerging climate science.

AGGG can be viewed as an antecedent of the Intergovernmental Panel on Climate Change. Policy-makers were starting to understand the serious long-term implications of the scientific findings, and concluded that AGGG needed to be superseded by a new, independent official group under the direct control of representatives appointed by each nation. Responding to this request, WMO and UNEP jointly created the Intergovernmental Panel on Climate Change (IPCC) in 1988, tasked to regularly take stock of the science for government purposes and examine options for responding to human-induced climate change. Creation of the IPCC provided the institutional base for more focused, better-coordinated examination of needed science-policy interactions at the international level. Bert Bolin, who was a member of AGGG and an author of the SCOPE report, was appointed the first IPCC chairman.

Throughout the 1980s, evidence mounted that climate change was one part of a larger phenomenon – global change – requiring an even wider scientific view and building connections among geophysics, chemistry and biology. This awareness eventually led to the launch of the ICSU-sponsored International Geosphere-Biosphere Programme (IGBP) at the ICSU General Assembly in 1986. IGBP was created to address the Earth as a system of globally interacting phenomena, and to understand the physical, chemical and biological processes that regulate this system, changes occurring to these processes and the role of human activities in these changes.

In a sequel to the successful 1979 Conference that led to the creation of WCRP, ICSU and WMO sponsored a second World Climate Conference in Geneva in October 1990. That Conference was a further milestone in the recognition of the reality of climate change. It received the First Assessment Report from the IPCC. A key chapter on a scientific action plan for improved prediction of global climate change was co-authored by the Chairs of the WCRP and the IGBP.

The publication of the IPCC’s First Assessment report in 1990 spurred governments to negotiate the United Nations Framework Convention on Climate Change (UNFCCC), which was ready for signature at the 1992 United Nations Conference on Environment and Development (UNCED) – also known as the “Earth Summit” – in Rio de Janeiro.

The IPCC Second Assessment Report of 1995 provided important material drawn on by negotiators in the run-up to the adoption of the Kyoto Protocol to the UNFCCC in 1997. WCRP and IGBP played a key role in coordinating the research that was assessed by the IPCC.

This text is taken from the brochure “The International Council for Science and Climate Change: 60 Years of Facilitating Climate Change Research and Informing Policy”.