Temperatures have increased by .85 degrees celsius since 1880, a shift more rapid than that of the end of the last ice age. Such an increase in temperature is already causing increases of extreme weather events such as heat waves, flooding, droughts, rising sea levels, and storms. Further dangers include the risk of ocean acidification which could be fatal for many marine ecosystems.
Many of these events disproportionately occur in underdeveloped regions of the world, which do not have adequate political and physical infrastructure to address these crises. Further, these regions are likely already unstable due to issues of immigration, food insecurity, refugees, and civil wars. These extreme weather events, particularly droughts, will only add fuel to the fire and act as a force multiplier on previously existing conflicts and grievances.
While the full extent and responsiblity of global warming in conflicts will likely never be known, the recent wave of unrest across the Middle East was surely spurred on by persistent drought and subsequent increases in food prices. Food prices played an integral role in the beginnings of the Egyptian and Tunisian revolutions just a few years ago, and Syria's longstanding drought in rural regions surely amplified pre-existing grievances against the state, sparking the Syrian conflict as well.
The report does not give much occasion for optimism. It shows that global temperatures will likely rise above 2 degrees Celsius, the danger threshold for climate change and the internationally set goal for limiting such change. By the end of the century the report warns, temperatures may rise by up to 3.7 degrees Celsius.