Hurricane tracks, changes in hurricane clustering, and other notes from Tucson
I'm in Tucson for the American Meteorological Society's 29th Conference on Hurricanes and Tropical Meteorology. This is the premier scientific conference on hurricanes, and is held only once every two years, so pretty much all of the world's greatest hurricane experts are here. Below are some quick snapshots of four of the talks I attended yesterday; I hope to more more snapshots each day this week.
Angela Colbert of the University of Miami/RSMAS showed how different weather and climate patterns affect the Azores-Bermuda High, and thus the tracks of Atlantic hurricanes. She divided storms into straight-moving storms that move straight west-northwest through the Caribbean, recurving landfalling hurricane that hit the east coast of the U.S., and recurving ocean storms that miss land. Roughly 1/3 of all hurricanes between 1950 - 2009 fell into each of these three categories. These proportions stayed pretty constant during La Niña and neutral years, but El Niño caused a weakening of the high, resulting in far fewer hurricanes hitting the U.S. East Coast. These storms instead recurved out to sea.
Jim Kossin of the University of Wisconsin separated all Atlantic storms from 1950 - 2007 into 4 clusters, based on genesis location. Two of the clusters were more northerly-forming storms that tended to be less tropical in nature--Gulf of Mexico storms, and storms off the U.S. East Coast that tended to recurve. The other two clusters were more southerly tropical-origin systems--ones that tended to form in the Caribbean, and storms that form near the Cape Verde Island region off the coast of Africa. The more tropical Cape Verde and Caribbean storms dominated major hurricane frequency by a factor of four. In mid-1980s, there was an abrupt shift to more of these more dangerous tropical type storms--ten years prior to the active hurricane period that began in 1995. It is unknown what caused this shift. The shift is unlikely to be a result of measurement error, since we had good satellite imagery then. Independent of any trends in frequency, this shift caused an increase in intensity metrics of Atlantic hurricanes. A doubling of these tropical systems has also occurred since 1950. Interestingly, there has been no change in the number of Gulf of Mexico storms, and a slight increase in storms forming off of the U.S. East Coast. Since slight changes in track can make a big difference in what SSTs and atmospheric environment a storm sees, there is a lot of natural "noise" in the system that will make it difficult to get a clear sense of when climate change is having a substantial impact on hurricane intensity.
Bin Wang of the University of Miami studied the global number of storm days from 1965 - 2008, which should be a less sensitive quantity to data problems than the number of storms or their intensity. Storm days were defined as any day when a tropical cyclone of tropical depression strength or greater existed. However, there are still some data problems, as evidenced by a sharp drop in storm days observed in the North Indian Ocean beginning in 1978. Dr. Wang found that there was no global trend in storm days. The Atlantic was the only individual basin that showed an increase in storm days.
Greg Holland of NCAR looked at the distribution of the strongest hurricanes over time by using a mathematical description of the historical hurricane data. His analysis showed that during the period 1995 - 2008, we probably had about a 30% increase in Category 5 storms in the Atlantic, and an 18% increase in Category 4 hurricanes. Using a climate model, he predicted that by the years 2045 - 2055, we should see a 60% increase in Cat 5s, 32% increase in Cat 4s, and 16% increase in Cat 3s in the Atlantic.
Jeff Masters
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I live at 146th and Vine...so the eye will probally miss me. Maybe Aug. 8th.
2010 May 11th GOM
The GOM cool rumor was and always has been that.
Were way above the Climatological Norm and last year easily.
If ya gonna blog on it..ya have to do da work..
LOLOL Brilliant!
That is their job. Doesn't mean it's going to happen.
That's a good point......
No, that's true of every single prediction of anything in the world, but I think we have enough knowledge of how the weather works to make general predictions of track congregations in advance. We don't know nothing. If we know that we're going into a La Nina and a cold PDO, with a certain SST profile in the Atlantic, we can get a broad idea of where tracks will likely tend to congregate in greatest concentration.
they changed it, take this ominous white wall as a premonition that hurricane season is almost here
Yeah. I see that nasty weather has been hanging around that part of the country for a while. Tornados, Hail, Floods, bad.
Where did the [pink graphic] from the PSD at NOAA of the most recent AMO go? It just vanished .... mysteriously. The adjacent links were unavailable to the public earlier, I noted, so ... you don't suppose?
Looking for a cached copy, but this isn't my forte.
Water flows from one of the diversions
Quantcast
Gulf Oil Spill
State officials have opened up six diversions along the river, from St. Charles Parish to Plaquemines Parish. The diversions allow the Mississippi waters to act as a flushing system for the coast.
by Maya Rodriguez / Eyewitness News
wwltv.com
Posted on May 12, 2010 at 9:01 PM
Updated today at 9:15 PM
As a massive oil spill in the Gulf of Mexico continues to spread, federal, state and local officials are looking at a number of ways to try and keep the oil away from the coast. One idea includes harnessing the power of the mighty Mississippi River to protect the state's coastal marshes.
"We're going to have peak water, in about five more days, coming down the Mississippi River," said Garret Graves of the Louisiana Coastal Protection and Restoration Authority.
State officials have opened up six diversions along the river, from St. Charles Parish to Plaquemines Parish. The diversions allow the Mississippi waters to act as a flushing system for the coast.
"It really could provide a fresh water wedge potentially against encroaching oil," said Tim Doody, president of the Southeast Louisiana Flood Protection Authority East.
One path the water is traveling through includes the Caernarvon diversion, on the border between St. Bernard and Plaquemines Parishes. Fresh water is moving through there at 8,000 cubic feet per second.
"We're trying to get as much fresh water as we can into both the Barataria Basin and Breton Sound area on the east bank," Graves said.
While the diversions are expected to keep some of the oil out of the coastal marshes, they could have some unintended consequences. Fresh water could throw off the salinity levels along the coast, affecting fisheries and estuaries. The alternative, though, is considered far worse.
"The ecological disaster that is this oil spill, far outweighs the potential for harm," Doody said.
Officials are now considering opening up the Bohemia Spillway, on the east bank of Plaquemines Parish. It could help divert even more of the river's water.
"That diversion actually has the capacity to run a couple hundred thousand cubic feet of water per second," Graves said. "So, [it has] a very, very large diversion potential."
The idea is now under serious consideration, but a decision will need to be made quickly. The Bohemia Spillway can only be used when the Mississippi River is high. It is now expected to crest at the Carrollton Gage on May 19.
"This is a different usage of the [Bohemia] Spillway than was ever intended," Doody said. "It was only intended as a flood control feature."
Officials have said they also considered opening up the Bonnet Carre Spillway, but because of its location, they don't believe it would be as effective as the other diversions.
Actually, based on the climate model output (caveat!), a GFDL figures on fewer TS - cat3, but more cat 4 & 5:
The lesser TS - cat 3s is a product of some increased shear frm the GCMs, I think.
And a shift in the frequency of certain minimum central pressures:
(towards lower central pressures more often)
All based on the GCMs, though...with everything about them that is right, wrong, or unknown.
Nice writeup here: http://www.gfdl.noaa.gov/21st-century-projections-of-intense-hurricanes/
Nice wave at 30W.
Yuck..but this is a good reminder to be prepared
That is your theory Levi. No two Hurricane seasons have ever, ever been exactly alike. Somewhat similar…yes. After this season is over, it will be different than and make another analog year for upcoming seasons.
Send some for us too! (Jamaica)
Hmm, no 2 seasons are alike, of course, but I'll say, I'd take 1878 over what some are calling for. A little busy, but too terrible.
Concensus appears Caribbean will be first.
I know, I never suggested that any season would be exactly like another.
That doesn't mean they can't get close....
Ignoring the similarities between analog years would be a mistake. There are ways to effectively use them. And by the way, Accuweather has done a pretty good job the last few years with the track congregation.
Anyway, I just think our science is advanced enough to start taking these steps. Most already have like Dr. Gray and others.
I waiting on it!!!! :-) Because I'm tired of daily water lock offs!
I'll take 1998 before 2004, anytime I have a choice.
Oil spill video: Bob Marshall gives latest update
By Andrew Boyd, The Times-Picayune
May 12, 2010, 8:05PM
Times-Picayune Outdoors editor Bob Marshall gives the latest update on the BP oil spill in the Gulf of Mexico in this video.
"Special outlooks may issued if conditions warrant"
Hmmm... English not a prerequisite in college for met degree? LOL - looks like something I would type.
Yeah, well the number could have been a bit more than 12, seeing as how nobody was out there observing the systems that didn't hit land or ships. 12 back then was much above normal. But I could live with no major landfalls for sure.
Unfortunately, they don't come with guidance systems attached so we'll just have to see what happens.
Whoever posted that posted a temporary link, which you just put in your post. Those disappear after like an hour.
Of course. Would not be surprised if:
a. some of those storms were stronger out at sea than recorded
b. there were a couple not observed (and now, not listed)
I am incapable of uttering those two words. And yes typing is a form of uttering.
He's a kid, ROFL.
Goodnight all. Thanks for posting the updates Patrap but I cannot listen to a word of it until they say they have shut the infernal thing down.
Well I'd get comfortable..
Nothing is gonna work till DD-3 taps the relief well. All the moves now are for, well,..effort or show.
5 million gals spilled into the Environment and counting.
This, coupled with the SOI, makes 1878 appear very much like this year, but we can never really know.
Dat's a big grain of salt...
But could be similar once it is said and done...
Yes I know, and the feeling is mutual. I was just attempting some of your humor, though I probably failed. I do agree with you on your comment about analogs, but I do think we aren't completely in the dark when it comes to predicting tracks.
Some of those first steps in science over the last couple thousand years have done us some good, Levi!
We are cool. But I really believe that we will not see a depression in the Atlantic basin this month. Kinda agree? Almost halfway through the month. I know things can change on a dime, but just don’t see it happening before June 1st.
S Fla would not like this year.
Tough call here. 1998 the state was on fire. 2004 had alot of 'canes.
Yeah, I think there is a chance but not a great one. The next MJO pulse should be lighting up the Atlantic from May 25th to June 10th, putting most of the chance in June.
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