Widespread changes in extreme temperatures have been observed in many regions of the world over the last
50 years; most notably the higher frequency of high- temperature days and nights and heat.
There is good evidence for an increase of the more damaging intense tropical cyclone activity in the North Atlantic since about 1970, which is correlated with increases in tropical sea surface temperatures. However, according to the IPCC, to date there is no clear trend evident in the global annual number of tropical cyclones.