Based upon the new results of Kossin et al. (GRL, 2007), it looks like the IPCC SPM just barely covered itself in its proclamations on observed hurricanes: There is observational evidence for an increase of intense tropical cyclone activity in the North Atlantic since about 1970, correlated with increases of tropical sea surface temperatures. (realclimate.org)
There is observational evidence for an increase of intense tropical cyclone activity in the North Atlantic since about 1970, correlated with increases in tropical SSTs. (ipcc.ch)
That signal is translating into all sorts of events — droughts, intense rainfall, more intense tropical cyclone activity, crop stress, heat waves, and so on. (discovermagazine.com)