The Intergovernmental Panel on Climate Change: Previewing its Fifth Report

The Intergovernmental Panel on Climate Change has emerged in recent years as the world’s leading international body investigating the science, impact and human response to climate change. Its fifth major assessment of the state of the world’s climate will be published in September 2013.

Some of the major themes likely to be addressed in the fifth report include:

  • Impact of climate change on water and the earth system
  • Acidification of the oceans
  • Status of the polar ice sheets and corresponding sea level rises
  • Human adaptation to climate change and the role of sustainable development
  • The extent to which climate change can and is being mitigated

Supported by the United Nations General Assembly, the IPCC does not carry out original scientific research. Its role is to review, collate and comment on academic papers already subjected to peer-review and published in the scientific community.

Over 830 authors will prepare the fifty-chapter fifth report – known as AR5. Line-by-line review by experts and government representatives is an essential part of the process. The aim is to ensure that the final report is an objective and comprehensive assessment of current scientific information on climate change.

Although the final part of its fifth report is not due to be published until 2014, this year’s initial assessment will report on the physical science basis for climate change. The IPCC’s fourth report of 2007 has become a standard text for expressing the global scientific consensus on man-made climate change:

Human activities contribute to climate change by causing changes in Earth’s atmosphere in the amounts of greenhouse gases, aerosols (small particles), and cloudiness.

The fourth report goes on to acknowledge that the largest known source of these greenhouse gases is the burning of fossil fuels, which release carbon dioxide into the atmosphere.

While acknowledging that the planet does experience natural periods of change in its climate, the IPCC is clear that,

The human impact on climate [since the industrial revolution] greatly exceeds that due to known changes in natural processes, such as solar changes and volcanic eruptions.

Further working group reports in March and April of 2014 will reflect current research into both the mitigation of climate change and its impact on human society. Political and economic responses around the issue of sustainability will also be addressed.

The findings of the IPCC will be hugely influential in shaping further international action (or inaction) on climate change. Previous reports formed the basis for the Kyoto Protocol of 1997, which the American government famously signed but refused to ratify. The next round of global environmental talks will be shaped to a large extent by the issues and conclusions raided in the coming IPCC findings.

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