Emanuel 2005 stated:
The annual average storm peak wind speed summed over the North Atlantic and eastern and western North Pacific has also increased during this period, by about 50%.
Once again, I can’t reproduce this result. Here are my calculations.
First, here are my calculations of annual average storm peak wind speed from the archived data, using only storms with peak wind greater than 18 m/sec (applying definition in Landsea’s Comment on Emanuel.
Peak Wind . Left- Atlantic; center – W Pacific; right – Total
The next figure shows attempts to fit linear trends to the data; the blue segments correspond to ones that I experimented with in trying to make sense of the accumulated annual duration data.
Using fitted data, the increase from 1949 to 2004 is 11% (not 50%); if you take the year 2004 over year 1949, you get 19%; if you take the 5-year mean for 2000-2004 over 1946-1950, you get 7%. How did Emanuel get 50%? I have no idea, but I have no idea how he got 50% for the supposed increase in accumulated annual duration.
Script is here