I now would like to summarize the most important findings:
• It is very likely that the number of extreme warm days and nights has increased worldwide since 1950, and this is likely due to the increase of greenhouse gas concentrations.
• In the future, for the higher emissions scenarios, what is today a 1-in-20 year hottest day will become a 1-in-2 year event. This means the frequency of these extreme events will increase by a factor of about 4 in the next 30 to 40 years and by a factor of 10 by the end of the 21st century.
• In consequence, heat waves are projected to very likely last longer, to occur more frequently and to increase in intensity.
• Heavy precipitation has intensified on a global scale and with medium confidence this is already attributed to anthropogenic climate change. It is likely that a 1-in-20 year event of heavy precipitation will become a 1-in-5 to 1-in-15 year event by the end of the 21st century.
• Tropical cyclone activity is in the focus of many countries because their impact can be devastating. While there is low confidence of observed long-term trends over the past four decades, is likely that maximum wind speed will increase in the 21 century in response to the warming.
• More intense and longer droughts have been observed in some regions, and there is medium confidence that they will intensify in the 21st century, particularly in S Europe, in the Mediterranean, Central North America and Mexico, NE Brazil and Southern Africa.
http://web.mit.edu/cis/tirman.html