I wonder what Kerry Emanuel will have to say about these graphs.

I also wonder how we can explain the significance of these graphs to Al Gore. His film made a clear point of how we have had a large increase in TCs recently.

There’s an old American TV sitcom named “I Love Lucy”. Sometimes Lucy had some ” ‘splainin to do”. I think that anyone choosing to use the historical storm count has some ‘splainin to do about the pattern changes.

And if they do, they need to wary of Occam and his razor.

I just extracted initial storm readings and final readings. So here are some figures to contemplate. With so many storms in the 1st 50 years not being detected until reaching hurricane strength, it seems more than likely that many storms went unrecorded.

1851 to 1900 storms = 377
30=8, 35=102, 40=81, 50=63, 55=1, 60=22, 70=54, 80=14, 85=1, 90=28, 100=1, 110=2
Mean initial speed = 51
most common = 35
————
20=2, 25=19, 30=42, 35=48, 40=69, 45=7, 50=61, 55=1, 60=42, 65=4, 70=55, 80=12, 90=14, 110=1
Mean final speed = 49
most common = 40
___________
1901 to 1950 storms = 391
20=1, 25=3, 30=41, 35=233, 40=37, 45=8, 50=20, 55=4, 60=39, 65=5
Mean initial speed = 39
most common = 35
———-
15=24, 20=40, 25=82, 30=109, 35=58, 40=23, 45=16, 50=12, 55=7, 60=8, 65=4, 70=4, 75=1, 80=2, 85=1
Mean final speed = 32
most common = 30
___________
1951 to 2000 storms = 499
10=2, 15=6, 20=30, 25=255, 30=151, 35=29, 40=7, 45=6, 50=10, 60=3
Mean initial speed = 28
most common = 25
———–
10=5, 15=18, 20=53, 25=111, 27=1, 30=81, 35=59, 40=38, 45=47, 50=25, 55=14, 60=26, 65=10, 70=7, 75=2, 80=2
Mean final speed = 35
most common 25

w.

Here are some more animated gifs of the other classes. They clearly demonstrate the differences in detection over the last 150 years. Green for TD/TS and Blue for Cat 1,2.

Cat 1,2 anim. http://img165.imageshack.us/img165/21/cat12animug4.gif
T Storms anim. http://img165.imageshack.us/img165/4167/tstormsanimmb3.gif
T Depressions anim. http://img165.imageshack.us/img165/3625/tdepressionsanimjc1.gif

Take note of the total plots for Cat 1,2 and compare to Cat 3,4,5. In the 1851-1900 period Cat 1, 2 plots are higher than the other two periods. Yet is way down in Cat 3,4,5 plots compared with the other periods. The only reasonable explanation I can find for this is lack of ship/shore communication. Ships caught in 3,4,5 may not have had a very high survival rate. Also, what captain isn’t going to steer away from the storm when encountering a severe one.

With 1851-1900 likely severely under-reported, I tend to think those 50 years were likely the worst of the last 150. Can’t prove it though.

The TD/TS coverage has increased dramatically as the years have passed.

Answer – they guessed the windspeed. And guessed and guessed and guessed and guessed and guessed some more and then guessed again.

Thanks, Bob K!

I am confident that archived data of Pacific and Indian Ocean TCs would show a similar methodologcial improvement.