Seeding Hurricanes May Limit Intensity at Landfall
The weakening of Hurricane Florence has got me thinking again about seeding strong hurricanes as they approach the U.S. coast. The theory behind this is simple: Disrupt the core by any means necessary, after which the natural competition between bands away from the center and the broken-down core will prevent the storm from restrengthening. One of the biggest keys to this is when the storm is seeded. It has to be at the hurricane’s strongest point. If it’s still intensifying, then it can likely rebuild itself. Therefore you want to hit it when it’s maxed out and as it’s approaching the coast. In my opinion, it’s time to resurrect Project Stormfury (a previous attempt), but not with storms way out at sea, rather with strong storms within 24 hours of landfall.
The super typhoon that just hit the Philippines is another example. Its core was disrupted by the island. Here it is 12 hours after leaving the island:
It was going over very warm water on its approach to the Chinese coast, yet it continued to weaken. There’s no eye visible.
The processes that increase intensity in tropical cyclones rely on “focused fury,” if you will, at the center. Spread that fury out, and the storm cannot be as strong at the center. It’s not possible to diminish the total energy of the storm, but we can affect the distribution. The key is the disruption of the storm’s core and where the strength is in relation to its history. If the storm is in an area of peak favorability, then this is likely to work. But if it’s approaching the area of peak favorability, then it is unlikely to work, as the pattern is such that the atmosphere will piece it back together again. You want to hit the storm when it’s strongest, as it will then be forced to adjust, which takes time.
There are countless examples of storms that were very powerful when they hit. But after they came back out over water, they did not return to their former strength. The ups and downs of hurricane intensity, including eyewall replacement cycles, are well documented. You cannot prevent these things. In fact, if you really want to do something about hurricanes and intensities, seeding is far more economical and far more likely to work than thinking you can reduce carbon emissions and stave off hurricanes. Remember, the stronger the system, the more it takes to keep it strong. The key is striking when it’s strongest and on the approach.
My take on the weakening of Florence is that the overall pattern that has led to the complete demise of activity in the main development region — over the last four days, every tropical cyclone in the Atlantic Basin is weaker, and Hurricane Isaac at the height of the season dissipated on its way west — has a lot to do with it. In fact, if you look at our preseason forecast, you can see storms heading for the red zone we targeted and dying in areas farther south where they were rocking and rolling in 2017.
Last year’s preseason red zone:
There is currently no new activity in the main development region. In any case, Florence was coming out of the area for prime development. Chances are the dry air that hit her and disrupted the center was a byproduct of the overall pattern change that will lead to a quiet period over the next week. But I do think there will be one more period of higher-than-average activity later this month into October.
Once the disruption took place, the outer bands of the storm, which were over the very warm water to the northwest of the storm, competed with the center, and the storm could not fully tighten back up again. It did try as it approached the coast, as the angle it came in at, combined with the fact the bands over land no longer were competing as much, “focused” the energy again at the center. So the eye tightened back up. The key to my seeding idea would be to keep seeding in such a way that it diminishes the opportunity for tightening again, though by and large nature will take care of that by itself. It is very tough for a large storm, once weakened, to make a comeback.
How powerful was Florence even off her peak intensity? Well, North Carolina has been hit 56 times by hurricanes. Florence is likely to be the costliest storm in that state’s history. It was not as strong in peak winds as I thought it would be from five days out, but 24 hours’ worth of hurricane-force winds and rain totals of three feet are nothing to scoff at. Wilmington had its second-highest wind gust on record, and given the history of hurricanes there, that is impressive. Donna was a Category 3 when it went through there. Hazel was a Category 4! So Florence beat both of them. Interestingly enough, in my opinion it did not beat the most underrated hurricane in U.S. history, Helene, which despite staying 10 miles offshore produced a 135 m.p.h. gust. It is also the strongest storm recorded that far north at 930 mb. That name should have been retired, in my view.
Finally, I have a power and impact scale at Weatherbell.com that is meant to describe the overall power of the storm. On that scale, Florence at landfall was a strong Category 2. It is well worth noting that Sandy and Ike were major storms on that scale, and both did major damage. Wind is not the only aspect of a storm! The area covered by a spread-out storm means more damage farther away, though not as bad as at the center. The wind damage with Florence is likely to be in line with a Category 2 storm.
It’s also worth noting that while Florence mimicked Harvey in that they did so much damage in a weakened state (though Harvey was stronger at landfall) via slow movement and excessive rain, they moved slowly for different reasons. If you study hurricanes, you can see dozens of storms that stalled or moved slowly and weakened as they did. The most notable example is Flora in 1963, which stalled over eastern Cuba and dumped 100 inches of rain. It remained a hurricane while doing so. (It was a Category ¾ when it initially went inland).
Already, objectivity is being ruined. We have the usual suspects on one side blaming the president and saying Florence is a sign of human-induced climate change. I wonder what these other storms that were stronger would have done in this day and age? Seriously though, it’s an absurd argument, as the very fact Florence weakened is like nature poking a finger in the protagonists’ eyes. The “Category 6ers” came out saying we need a new category, but when the storm moderated, they simply moved to another element that is inherent in any storm — rainfall and movement.
They have no problem at all pushing their missive. Yet not one of them would bring up our forecast for the ACE (accumulated cyclone energy) peak that was made Aug. 23. Nor the prediction that after its peak, the entire tropical Atlantic production would collapse. These are natural processes. There are no new features in the tropical Atlantic Basin in mid-September!
On the other hand, references to this being less than what it is are also incorrect. Despite the long and storied history of North Carolina hurricanes, Florence did to a large part of the state what Harvey did to southeast Texas. Most of Harvey’s damage was due to rain while the storm was weaker. In Florence’s case, there were not as many people in the way. That being said, it was not as severe wind-wise as I thought it would be, and I think because of that it makes more sense to look at this seeding idea in an effort to disrupt powerful storms.
It certainly make more sense to me physically and economically to try to prevent nature’s extremes than to change our entire way of life when the real agenda has little to do with reality. As I wrote in my book, The Climate Chronicles, this is part and parcel of the weaponization of weather, and it’s only going to get worse. That the majesty and challenge of the weather is being dragged through the mud like this is the reason I wrote the book in the first place — to defend something I love: the pursuit of truth in the field God blessed me to work in.
Joe Bastardi, a pioneer in extreme weather and long-range forecasting, is a contributor to The Patriot Post on environmental issues. He is the author of “The Climate Chronicles: Inconvenient Revelations You Won’t Hear From Al Gore — and Others.”