Following the approval and release of the Working Group I contribution to the IPCC Fourth Assessment Report on February, which details the observed climate change, this Working Group II Summary concerns the relationship between observed climate change and recent observed changes in the natural and human environment. Conclusions include the following: (i) Observational evidence from all continents and most oceans shows that many natural systems are being affected by regional climate changes, particularly temperature increases; (ii) A global assessment of data since 1970 has shown it is likely that anthropogenic warming has had a discernible influence on many physical and biological systems; (iii) Other effects of regional climate changes on natural and human environments are emerging, although many are difficult to discern due to adaptation and non-climatic drivers...

URL: http://www.ipcc.ch/SPM13apr07.pdf