Climate change 2001: The scientific basis. Contribution of Working Group I to the Third Assessment Report of the Intergovernmental Panel on Climate Change

The earth’s climate system has demonstrably changed since the pre-industrial era, with some of these changes attributable to human activities. The consequences of climate change pose a serious challenge to policy-makers. Hence they need an objective source of information about climate change, its impacts and possible response options. Recognising this, the World Meteorological Organization (WMO) and the United Nations Environmental Programme jointly established the Intergovernmental Panel on Climate Change (IPCC) in 1988. The terms of reference of the IPCC include: