Hurricane Eye Wall Replacement Cycles: Nature or Technology?

It seems that so often these days you hear the hurricane center talk about the strength of storms and eye wall replacement cycles. These have an impact on the strength of the storm. What I'm wanting to find out is whether this existed prior to Hurricane Andrew. It "seems" that this happens as a storm is threatening the US. Maybe it is coincidence. Is it nature at work or technology at work? Look at storms like Gilbert, Mitch, Camile, Andrew, Hugo and Wilma. Look at the monster storms that his Australia this year. They all seem to escape the infamous eye wall replacement. These storms were either before Andrew (including Andrew) or not a threat to US economic interests. Check the satellite loops and see how convenient the weakening was.

Hurricane Floyd threatens the Florida space coast with a force so strong that it could basically wipe out the US space program. Floyd unexpectedly weaks greatly. Fortunately Floyd misses the coast and its a moot point.

Hurricane Frances was projected to hit the Florida space coast as a monster hurricane. I believe cat 4 was the prediction. Like Floyd it also falls appart unexpectedly.

Katrina threatens to wipe out a major US metro area and cause a severe disruption of oil flow from the gulf. Katrina mysteriously has one side of the storm wiped out around 24 hours before impact.

Rita threatens a big oil supply as well and mysteriously weakens dramatically before landfall.

There is always the theory that something is altering, directing or creating storms. Here is a chance for people to prove it or disprove it when it comes to hurricanes. Try and find proof of eye wall replacement cycles prior to Andrew. Try and find examples of this in other parts of the world where storms impact 3rd world nations. Don't mistake replacement cycles for storms getting ripped apart by upper level winds. The storms I mentioned weakened dramatically despite conditions that would not be classified as unfavorable.

Your help with this is appreciated.

Here you go. It was seen as early as 1980.

"Concentric eyewall cycles" (or "eyewall replacement cycle" ) naturally occur in intense tropical cyclones , i.e. major hurricanes (winds > 50 m/s, 100 kt, 115 mph) or Catories 3, 4, and 5 on the Saffir-Simpson scale. As tropical cyclones reach this threshold of intensity, they usually - but not always - have an eyewall and radius of maximum winds that contract to a very small size, around 10 to 25 km [5 to 15 mi]. At this point, some of the outer rainbands may organize into an outer ring of thunderstorms that slowly moves inward and robs the inner eyewall of its needed moisture and momentum. During this phase, the tropical cyclone is weakening (i.e. the maximum winds die off a bit and the central pressure goes up). Eventually the outer eyewall replaces the inner one completely and the storm can be the same intensity as it was previously or, in some cases, even stronger. A concentric eyewall cycle occurred in Hurricane Andrew (1992) before landfall near Miami: a strong intensity was reached, an outer eyewall formed, this contracted in concert with a pronounced weakening of the storm, and as the outer eyewall completely replaced the original one the hurricane reintensified. Another example is Hurricane Allen (1980) which went through repeated eyewall replacement cycles -- going from Categrory 5 to Category 3 status several times. To learn more about concentric eyewall cycles, read Willoughby et al. (1982) and Willoughby (1990a).

It was the discovery of concentric eyewall cycles that was partially responsible for the end of the U.S. Governements's hurricane modification experiment Project STORMFURY, since what the scientists had hoped to produce through seeding was happening frequently as a natural part of hurricane dynamics.

www.aoml.noaa.gov...

That is their story. What I'm looking for is proof. There is all kinds of data on the net. Endless satellite images. Find a good loop that shows this happening pre-Andrew. This didn't happen to Mitch, Gilbert, Andrew or Camile and these were the worst. Find evidence of an eye wall replacement cycle. Find one that compares to what happened to Floyd, Frances, Rita and Katrina.

just look:

www.enterprisemission.com...: there's more, of course, but this one's pretty convincing, imho.

Originally posted by Indy
That is their story. What I'm looking for is proof. There is all kinds of data on the net. Endless satellite images. Find a good loop that shows this happening pre-Andrew. This didn't happen to Mitch, Gilbert, Andrew or Camile and these were the worst. Find evidence of an eye wall replacement cycle. Find one that compares to what happened to Floyd, Frances, Rita and Katrina.

Okay, so we tell you that it occurred pre-Andew (ie Allen, in 1980). But because there aren't archives of satellite images on the internet from years before the internet existed, you won't believe us.

And anyway, everyone who can provide proof is in on the conspiracy.

Not much point is going on really, is there .....

Essan... it isn't difficult. But if you are simply wanting to dismiss it without the least bit of effort then you really have nothing else to add to this discussion. If you look through the archives on the net (and their are plenty when it comes to hurricanes) and you can find image loops from major hurricanes that show this process then I welcome you to present the evidence. Gilbert, Mitch and Andrew are very well covered What about the recent huge storms to hit Australia? Heck my 11 year old is constantly coming up with satellite images of hurricanes from years ago.

So you won't accept the testimony of hurricane experts or any other meteorologists, you'll only accept a satellite image loop?

I take it you know what a ERC looks like on satellite imaginery? And not just what those experts you refuse to listen to tell you it looks like?

And if I'm unable to find satellite imagery, what then? It proves meteorologists are all lying does it?

If you can provide a loop which clearly shows that an ERC did not occur when meteorlogists said it had, then maybe you'd have a better case?

Otherwise it's surely just a case of meteologists said an ERC occurred. I can't be bothered to track down satellite imagery of it. Therefore there must be huge conspiracy afoot..... Hardly the basis for a rational theory.


btw No loop of ERC, but still nice image of ST Oliwa's concentric wall clouds here:-

www.npmoc.navy.mil...




[edit on 5-7-2006 by Essan]

Looks obvious to me what it is (why have they speeded it up so much? )

I guess it all comes down to how much time you spend looking at satellite imagery.....

if you don't speed it up, you simply get a standstill, not what you want when you're trying to demonstrate a dynamic process, is it?

Ophelia... which reminds me of an old thread of mine (which never got any replies, btw ) : Aerosonde Flying Through Ophelia. That loop you have put here looks very weird, LongLance. Good find But this event happened only last year though. I wonder if this is "normal" behaviour of a hurricane? Maybe the Aerosonde did something to Ophelia?

Originally posted by Long Lance
if you don't speed it up, you simply get a standstill, not what you want when you're trying to demonstrate a dynamic process, is it?

Actually, I stand corrected - looking at it again I think it's because it's a smaller image that it looks faster.

The original is here