Alliances between international organizations:
Climate change

Michael Williams

Michael Williams,
UNEP

Michael Williams of UNEP supports press outreach for the IPCC reports on behalf of its two parent organizations. He previously served as spokesman for the annual conferences of the UN Framework Convention on Climate Change and the Kyoto Protocol.

UNEP / WMO: IPCC

A definitive new report on climate change

A partnership between UNEP and WMO has produced the world's most rigorous international process for scientific assessment.

The partnership between WMO and UNEP has been a particularly fruitful one over the years, but the creation of the Intergovernmental Panel on Climate Change (IPCC) may well be its crowning achievement. The IPCC is both an intergovernmental body and an extensive network of the world's leading experts on climate change. Its Secretariat is hosted in Geneva at the WMO, which is the authoritative scientific voice of the UN System on weather, climate and water.

The IPCC does not conduct new research or monitor climate-related data. Rather, its mandate is to assess the most up-to-date expert literature on climate change, the great bulk of which has been published in peer-reviewed journals in various languages and regions. Rather than highlighting just one or two research findings of particular interest, the IPCC reviews the full breadth of available studies and analyses. In this way, the Panel has made itself into the world's most widely accepted objective source of scientific, technical and socioeconomic information about climate change and its causes, impacts and response options.

2007 has been a particularly important one for the IPCC as it marks the launching of its Fourth Assessment Report. The result of over three years' work by several thousand experts, the so-called AR4 has already made a powerful impact on both the general public and policymakers. The first volume of the report, released in Paris on 2 February, concluded that major advances in climate modelling and the collection and analysis of data now give scientists «very high confidence» (at least a 9 out of 10 chance of being correct) in their understanding of how human activities are causing the world to warm. This level of confidence is much greater than what could be achieved in 2001 when the IPCC issued its last major report.

The report's second volume, launched in Brussels on 6 April, assessed the current and future impacts of global warming and explored opportunities for proactively adapting to them. It concluded that the world's rivers, lakes, wildlife, glaciers, permafrost, coastal zones, disease carriers and many other elements of the natural and physical environment are already responding to the effects of humanity's greenhouse gas emissions. Rising temperatures are accelerating the hydrological cycle and causing rivers and lakes to freeze later in the autumn and birds to migrate and nest earlier in the spring. Scientists are increasingly confident that, as global warming continues, certain weather events and extremes will become more frequent, widespread or intense.

The third volume on mitigation was issued in Bangkok on 4 May. It confirmed that the world community could slow and then reduce global emissions of greenhouse gases (GHGs) over the next several decades by exploiting cost-effective policies and current and emerging technologies. Based on the most up-to-date, peerreviewed literature on emissions modelling, economics, policies and technologies, this volume reveals how governments, industry and the general public could together reduce the energy and carbon intensity of the global economy despite growing incomes and population levels.

The latest IPCC report on climate change confirms that the evidence for human-caused global warming is now «unequivocal».

The fourth and closing volume of this series, in November 2007, synthesizes the findings of the first three volumes. The entire report will be published by Cambridge University Press, but it will also available as separate chapters on the IPCC's website.

Because they are designed to be policy relevant rather than policy prescriptive, the IPCC's assessment reports are able to play an extremely constructive role as policymakers grapple with making difficult political choices about how to address climate change. The reports provide a solid, objective and politically accepted base of information and knowledge. With this base firmly established, the politicians are freed to debate politics rather than science. They can focus on setting priorities and making the choices amongst various options and values that the voters have elected them to make.

The IPCC will long remain a critical part of the global effort to confront global warming, with a technical paper on climate change and the critical issue of water resources at the end of 2007. Looking further ahead, we can expect to see many more of the IPCC's invaluable assessment reports in the years to come.

www.ipcc.ch/