According the IPCC Reort 2012 "Managing the risks of extreme events and disasters to advance climate change adaptation", it is very likely that the length, frequency, and/or intensity of warm spells or heat waves will increase over most land areas. Based on the A1B and A2 emissions scenarios, a heat event which currently occurs every 20 years is likely to occur every second year by the end of the 21st century in most regions, except in the high latitudes of the Northern Hemisphere, where it is likely to occur every 5 years.