Re: [Phys-L] measuring hurricane strength

["Folkerts, Timothy J" <FolkertsT@bartonccc.edu>]

John D says:
>  There is no defined upper bound to category 5, and no 
> category 6, because the guys who proposed the scale 
> could not imagine a storm strong enough to require one.

Not according to Wikipedia. 
"According to Robert Simpson, there are no reasons for a Category 6 on the Saffir-Simpson Scale because it is designed to measure the potential damage of a hurricane to man-made structures. Simpson stated that "...when you get up into winds in excess of 155 mph (249 km/h) you have enough damage if that extreme wind sustains itself for as much as six seconds on a building it's going to cause rupturing damages that are serious no matter how well it's engineered.""

In any case, I am not quite sure how this relates to my comment about Accumulated cyclone energy (ACE) --  "an approximation of the wind energy used by a tropical system over its lifetime and is calculated every six hours".  This parameter shows no long-term upward trend in either the Atlantic or Pacific, despite warmer surface water and presumably warmer subsurface water. 
https://en.wikipedia.org/wiki/Accumulated_cyclone_energy

I have learned there is also an "Integrated Kinetic Energy" index, but it is hard to find much info about it.