The Intergovernmental Panel on Climate Change (IPCC) is a group of scientists from around the world, brought together by the United Nations to assess our understanding and the potential impacts of climate change. Every five years they do a follow-up study to assess recent findings. Most important, they are identifying our options for lessening the rate of change and describing how societies can adapt to it. According to the IPCC's current findings, the world's surface air temperature has increased an average of 0.6�C (1.0 �F) during the 20th Century. That may not sound like very much,but even one degree can cause changes around the world. Additionally, given the accelerating rate of temperature rise, the IPCC projects that during the 21st century, temperatures will rise much more than they did during the past century. Since temperatures will likely continue to climb it is important to understand how the Earth has responded to climate change during the past century and to be able to better predict how it may respond in the future. The impacts of climate change listed within this section are just a handful of those explained in the IPCC's Climate Change 2001 report.
Take a look at the full report at: http://www.grida.no/climate/ipcc_tar/