Abstract: "Climate Change 2007? Impacts, Adaptation and Vulnerability", the Working Group II contribution to the IPCC Fourth Assessment Report (AR4) was launched on April 6, 2007. This report summarize the newest peer-reviewed and comprehensive findings from international scientific communities on impact and adaptation. The observed evidence shows that it is likely that anthropogenic warming has had a discernible influence on many physical and biological systems, but many are difficult to discern due to adaptation and non-climatic factors. By the mid-21th century, annual average river runoff and water availability are projected to decrease by 10%~30% over some dry regions at mid-latitudes and in the dry tropics; Approximately 20%~30% of plant and animal species assessed so far are likely to be at increased risk of extinction if increases in global average temperature exceed 1.5~2.5℃; Globally, the potential for food production is projected to increase with increases in local average temperature over a range of 1~3℃, but above this it is projected to decrease. A portfolio of adaptation and mitigation measures can diminish the risks associated with climate change.

Key words: climate change, impacts and adaptation, IPCC WGII, the Fourth Assessment Report