Detection and attribution
It remains uncertain whether past changes in any tropical cyclone activity (frequency, intensity, rainfall, and so on) exceed the variability expected through natural causes, after accounting for changes over time in observing capabilities.
Tropical cyclone projections
Frequency. It is likely that the global frequency of tropical cyclones will either decrease or remain essentially unchanged owing to greenhouse warming. We have very low confidence in projected changes in individual basins. Current models project changes ranging from ?6 to ?34% globally, and up to ±50% or more in individual basins by the late twenty-first century.
Thomas R. Knutson1*, John L. McBride2, Johnny Chan3, Kerry Emanuel4, Greg Holland5, Chris Landsea6, Isaac Held1, James P. Kossin7, A. K. Srivastava8 and Masato Sugi9
http://www.aoml.noaa.gov/hrd/Landsea/knutson-et-al-nat-geo.pdf
Of course that contradicts earlier claims of increases with warming. As was brought up a couple of years ago in a discussion on this subject: How hard is it to admit in public: We do not know? The reason the we do not know claim is made is because non of the MSM wants that answer and the political activists only want dire predictions.
And interesting article Steve;
“Some increase in the mean maximum wind speed of tropical cyclones is likely with projected twenty-first century warming, although increases may not occur in all tropical regions. This conclusion has been supported by theories of potential intensity”