On September 27 the Intergovernmental Panel on Climate Change (IPCC) presented a summary for policy makers of the Working Group I contribution to the Fifth Assessment Report (AR5).

The Working Group I report, named Climate Change 2013: the Physical Science Basis, has assessed the global and regional-scale climate change for the early, mid, and later 21st century. Thanks to improved models, better observations and understanding of the climate system, the resulting analysis shows an evident human influence on the earth climate. The studies reveal how the last three decades have been the warmest since 1850, causing ice melting and sea level raise as well as a greater frequency of extreme events.
If greenhouse gas emissions keep increasing, further warming and changes in all components of the climate system will happen. In this respect, the report present four possible scenarios of temperature raise up to the end of the century and the consequent impacts on the climate.

AR5 will be completed later next year after the publication of the contributions by Working Group II (Climate Change 2014: Impacts, Adaptation and Vulnerability) and Working Group III (Climate Change 2014: Mitigation of Climate Change) and the Synthesis Report, in March, April and September 2014 respectively.

For more information please visit the IPCC official website.