Comments 1 to 8:

1. nigelj at 11:30 AM on 25 October, 2019

   link.springer.com/article/10.1007/s00382-013-1713-0

   "We find no anthropogenic signal in annual global tropical cyclone or hurricane frequencies. But a strong signal is found in proportions of both weaker and stronger hurricanes: the proportion of Category 4 and 5 hurricanes has increased at a rate of ~25–30 % per °C of global warming after accounting for analysis and observing system changes. This has been balanced by a similar decrease in Category 1 and 2 hurricane proportions, leading to development of a distinctly bimodal intensity distribution, with the secondary maximum at Category 4 hurricanes. This global signal is reproduced in all ocean basins."

   So increasing frequency of  category 4 and 5 hurricanes, with stalling patterns and higher levels of rainfall. A potent mix.

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2. SteveW at 00:42 AM on 27 October, 2019

   Must be very inconvenient for you that Total Accumulated Cyclonic Energy worldwide shows no change throughout all the climate change hysteria of the last decades. Guess wishing it were so doesn't have much effect!

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   Inflammatory tone and language snipped.

3. Tom Dayton at 01:54 AM on 27 October, 2019

   SteveW: I don't think total accumulated cyclonic energy would be increased by stalling patterns of hurricanes. I don't think there is anything close to a consensus that total accumulated cyclonic energy will be increased by global warming. Instead, the weak consensus among climatologists is that the number of hurricanes will be unchanged or might even decrease, while the number of very strongest hurricanes will increase.

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4. nigelj at 06:15 AM on 27 October, 2019

   Steve W it must be very inconvenient for you that the data shows the numbers of category 4 and 5 hurricanes are increasing as in the link I posted. These are the ones that cause by far the most damage. It's trivially obvious that global warming pushes more energy into the earths system so this must by definition effect all weather systems, so its a question of how, and it doesn't necessarily mean you get a simplistic response like more global cyclonic energy, because weather systems are complicated.

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5. One Planet Only Forever at 08:17 AM on 27 October, 2019

   Claims like the one made by SteveW, that all is well because "Accumulated Cyclonic Energy (ACE) is not increasing", always seem to have to dismiss the bigger picture.

   Selective points can be turned into any claim, as long as many related counter-points can be ignored. (As a tongue-in-cheek example, I know a Steve who is very resistant to learning new things, especially if the new learning would require him to give up something he developed a liking for benefiting from, so I expect other Steves to be inclined to be like that. Maybe this Steve will prove me to be wrong about that).

   In addition to nigelj's point about the expected increase of category 4 and 5 events (presented in a 2013 paper analyzing satelite data from 1975 to 2010, and not evaluating ACE), I would add that there also appear to be recent cyclones with sustained wind speeds so high that a Category 6 should be added.

   Back to ACE, by reviewing a few sites I have found that many evaluations are limited in scope. They are not complete global evaluations.

   The evaluations 'lacking a clear increased signal' are likely regarding the most commonly reported Atlantic Hurricane events (they exclude Typhoons). I did, however, come across a Wikipedia presentation regarding Accumulated cyclone energy that includes a presentation of Atlantic basin hurricane season values from 1851 to 2019 showing that a significant number of Hyperactive and Above Normal years have occurred since 1995. That appears to contradict a claim about a lack of increase, even in that limited scope of the globe (unless the claim is that there is no clear evidence of an increase within that most recent 20 year set of clearly higher values - which needs a two-faced way of looking at things, or a desire for a myopic view).

   In addition to that point, a discussion of Hurricanes is not the full story. All cyclonic activity matters, not just the potential to affect USA territory. There are also Typhoons and, in addition, they seem to be increasingly damaging (irrespective of whether there is a measured increase of ACE).

   And the even bigger story is that, in addition to 'longer lingering hurricanes producing more damage', more intense and damaging Tropical Storm level events (sustained winds below hurricane levels), also appear to be occurring.

   Maybe SteveW would care to prove that my generalization about all Steves is wrong by providing a comprehensive and verifiable evaluation of what is really going on regarding all aspects of cyclonic events, the Big Picture (or will SteveW prove to be resistant to learning new things, especially if the new learning would require him to give up something he developed a liking for benefiting from).

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6. Daniel Bailey at 09:32 AM on 27 October, 2019

   Current 2019 global ACE is 111% of normal YTD values.

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7. MA Rodger at 19:56 PM on 27 October, 2019

   The difficulty with arguing about tropical cyclones with trolls is two-fold. Firstly global-wide records only stretch back to 1970 meaning that the increase in ACE 1970-on, a NH phenomenon (see bottom graph in link @6) which is a statistically significant decadal rise of 5%(+/-2% - 2sd), is too short given the wobbles evident in the one long record we do have (the N Atlantic). 

   Secondlly, where records are of a useful length (ie the North Atlantic graphed above), their reliability of the data back in the day of sailing ships and quill pens puts the trend (with its narrower statistical significance) into doubt.

   Mind, I see one poorly discussed phenomenon that demonstrates we probably are stoking up a whole heap of trouble with future tropical cyclones. The 2017 North Atlantic season started very very quietly. Then from late August through to October, it went crazy, smashing all records for ACE over that period. Eight storms, all hurricanes, six of them major.

   

   And it looks like we were not far off a repeat in 2019. Again a very quiet start then come the end of August the storms start ramping up. ACE for September was well short of 2017 but otherwise head-&-shoulders above recent years. Unlike 2017, only four of the nine storms wound up into hurricanes but three of those managed to reach major categories.

   As it is with rain data, tropical cyclone activity is very lumpy which makes identifying trends very difficult - very difficult but not impossible. And, paraphrasing the troll @2 (although snipped) "wishing it weren't so doesn't have much effect!"

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8. trmpttiger3 at 03:16 AM on 30 October, 2019

   Last year after Hurricane Florence made her deadly stall on the coasts of the Carolinas, I sent an email to the National Hurricane Center asking them if it was time to revamp the Saffir-Simpson Scale since wind speeds are taking a backseat to rainfall and storm surges in the more recent hurricane impacts.  They agreed and said that they were indeed working on such a system, but that it may take time for acceptance since the public is so used to the Saffir-Simpson scale.  I think we would be better informed on the potential devastation for a hurricane if we knew the estimated rainfall and storm surge.

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