Modiki El Niños and Atlantic hurricane activity
It's an El Niño year, which typically means that Atlantic hurricane activity will be reduced. But not all El Niño events are created equal when it comes to their impact on Atlantic hurricane activity. Over the past 150 years, hurricane damage has averaged $800 million/year in El Niño years and double that during La Niña years. The abnormal warming of the equatorial Eastern Pacific ocean waters in most El Niño events creates an atmospheric circulation pattern that brings strong upper-level winds over the Atlantic, creating high wind shear conditions unfavorable for hurricanes. Yet some El Niño years, like 2004, don't fit this pattern. Residents of Florida and the Gulf Coast will not soon forget the four major hurricanes that pounded them in 2004--Ivan, Frances, Jeanne, and Charley. Overall, the 15 named storms, 9 hurricanes, and 6 intense hurricanes of the hyperactive hurricane season of 2004 killed over 3000 people--mostly in Haiti, thanks to Hurricane Jeanne--and did $40 billion in damage.
A new paper published in Science last Friday attempts to explain why some El Niño years see high Atlantic hurricane activity. "Impact of Shifting Patterns of Pacific Ocean Warming on North Atlantic Tropical Cyclones", by Georgia Tech researchers Hye-Mi Kim, Peter Webster, and Judith Curry, theorizes that Atlantic hurricane activity is sensitive to exactly where in the Pacific Ocean El Niño warming occurs. If the warming occurs primarily in the Eastern Pacific, near the coast of South America, the resulting atmospheric circulation pattern creates very high wind shear over the tropical Atlantic, resulting in fewer hurricanes. This pattern, called the Eastern Pacific Warming (EPW) pattern, occurred most recently during the El Niño years of 1997, 1987, and 1982 (Figure 1). In contrast, more warming occurred in the Central Pacific during the El Niño years of 2004, 2002, 1994, and 1991. The scientists showed that these Central Pacific Warming (CPW) years had lower wind shear over the Atlantic, and thus featured higher hurricane activity than is typical for an El Niño year. One of the paper's authors, Professor Peter J. Webster, said the variant Central Pacific Warming (CPW) El Niño pattern was discovered in the 1980s by Japanese and Korean researchers, who dubbed it modiki El Niño. Modiki is the Japanese word for "similar, but different".
Figure 1. Difference of Sea Surface Temperature (SST) from average during the peak of hurricane season, August-September-October, for seven years that had El Niño events (except for 2009, when the SST anomaly for July 1 - 3 is plotted). On the left side are years when the El Niño warming primarily occurred in the Eastern Pacific (EPW years). On the right are years when the warming primarily occurred in the Central Pacific (CPW years). Shown on the top of each plot is the number of named storms (NS), hurricanes (H), and intense hurricanes (IH) that occurred in the Atlantic each year. Atlantic hurricane activity tends to be more prevalent in CPW years than EPW years. An average hurricane season has 10 named storms, 6 hurricanes, and 2 intense hurricanes. Image credit: NOAA/ESRL.
What, then, can we expect the current developing El Niño event to do to 2009 hurricane activity? Kim et al. note that in recent decades, the incidence of modiki CPW El Niño years has been increasing, relative to EPW years. However, the preliminary pattern of SST anomalies in the Pacific observed so far in July (lower left image in Figure 1) shows an EPW pattern--more warming in the Eastern Pacific than the Central Pacific. If Kim et al.'s theory holds true, this EPW pattern should lead to an Atlantic hurricane season with activity lower than the average 10 named storms, 6 hurricanes, and 2 intense hurricanes. There is still a possibility that the observed warming pattern could shift to the Central Pacific during the peak portion of hurricane season, however. We are still in the early stages of this El Niño, and it is unclear how it will evolve.
Jeff Masters
Reader Comments
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You are correct...all of the tools we have for genesis are screwdrivers.
GFS is a global model.
In a nod to the Japanese, once we get to an operational NICAM, we will have something useful. A global cloud-resolving model that can adequately track the MJO amplitude and phases is what is going to get us to a point where cyclogenesis can be effectively modeled.
http://nicam.jp/
Currently, our operational global models are too coarse to handle the clouds, ITCZ, MJO, and mesoscale, and smaller, convergence.
This is the same reason the GFS spins up an existing hurricane at only 3/4 of observed wind velocities, even with vortex bogussing.
Reflector site for those at work, which includes Weather456, daily updates
AOI
AOI
Except Linux. I have my finger on which ports any particular machine allows incoming traffic on...and that usually does not include those used for http traffic.
Does one have to create a blog to be able to ignore or ban people? (no one on here lol)
I dont see the options on my blog
Yes
You do not have to put anything in it, but you have to initialize it.
The Cape Verde Season is fast approaching...
Recurving Vs Landfalling Cape Verde Hurricanes
Thanks I got it
Think of it as your own personal forum. You can't jump into Random Person B's forum and begin ignoring / banning people. Here you must take the good, the bad, and the dregs in stride. Speaking of which thats all the long-range GFS is giving us...ever gives us...
never said I was doing that, I was just asking
Hey, you're right, it doesn't, officially.
"All GFS runs obtain their initial conditions from a three-Dimensional Variational (3-D VAR) Gridpoint Statistical Interpolation (GSI), which is updated continuously throughout the day. Rather than inserting data corresponding to an artificial TC vortex ("bogusing"), the GFS relocates the globally-analyzed TC vortex in the first-guess field to the official NHC position. An assimilation of the available (real) data is then performed to create the initial state."
http://www.nhc.noaa.gov/modelsummary.shtml
Somewhat accomplishing the same thing, though. So the GFS is using the NHC position and the NHC is partly using the GFS for position...circular. Doesn't seem like a good idea...
I guess we interpret this differently. If it's a circle, it would be about position. Not an artificial vortex.
Rather than inserting data corresponding to an artificial TC vortex ("bogusing"), the GFS relocates the globally-analyzed TC vortex in the first-guess field to the official NHC position. An assimilation of the available (real) data is then performed to create the initial state."
EP 95 2009070912 BEST 0 95N 1090W 25 1009 DB
El Nino weather anomaly has developed and it may not be as strong as the killer which struck more than a decade ago, the U.S. Climate Prediction Center said Thursday.
The CPC, an office under the National Oceanic Atmospheric Administration, said in a monthly update "conditions in the equatorial Pacific transitioned from neutral to El Nino conditions."
It said current trends favor development "of a weak-to-moderate strength El Nino into the northern hemisphere fall (of) 2009, with further strengthening possible thereafter."
This El Nino is developing just as the world struggles to emerge from the worst financial crisis since the Great Depression of 1929.
The last severe El Nino in 1997/98 killed more than 2,000 people and caused billions in damages to farms and infrastructure in countries from Indonesia to Peru.
El Nino means 'little boy' in Spanish. It causes an abnormal warming of waters in the Pacific which in turn would unhinge weather patterns in the Asia-Pacific -- spawning drought in Australia and Indonesia while causing floods in Peru and Ecuador.
The 1997/98 El Nino struck in the middle of the Asian financial crisis which roiled financial markets.
Some forecasters have said this El Nino may have played a role in delaying the arrival of annual monsoon rains in India which play such a critical role in its farm economy.
Drought would pose a major risk to Australian wheat production and damage palm oil output in Indonesia and Malaysia.
The CPC report said El Nino may also "help to suppress Atlantic hurricane activity by increasing the vertical wind shear over the Caribbean Sea and tropical Atlantic Ocean."
Storms sweeping in from the Atlantic or in the Gulf would threaten oil rigs in the area and menace crops from Mexico, the Caribbean and into the southern United States.
The low pressure area East of Northern Luzon has developed into a tropical depression and was named "GORIO".
Tropical Cyclone Bulletin #1
========================
At 5:00 PM PhST, Tropical Depression Gorio located at 18.3°N 125.3°E or 340 km east of Aparri, Cagayan has 10 minute sustained winds of 55 km/h (30 knots).
Signal Warnings
=================
Signal Warning #1 (30-60 kph winds)
Luzon Region
1.Cagayan
2.Calayan group of Islands
3.Babuyan group of Islands
4.Northern Isabela
5.Kalinga
6.Apayao
7.Abra
8.Ilocos Norte
9.Batanes
Additional Information
=======================
TD "GORIO" is expected to enhance the southwest monsoon and bring rains over the western section of Luzon and western Visayas.
Residents in low lying areas and near mountain slopes are advised to take all the necessary precautions against possible flashfloods and landslides.
The public and the disaster coordinating councils concerned are advised to take appropriate actions and watch for the next bulletin to be issued at 11 PM today.
New paper about the application of QuikScat and it's known limitations:
Link.pdf
Specifically:
Limitations of QuikSCAT in NHC operations
The major limitations of QuikSCAT from the NHC
operational perspective include the following:
1) the inability to resolve the maximum winds in the inner core of most hurricanes due to insufficient retrieval resolution, instrument signal saturation (which limits the maximum retrievable wind speed, even in rain-free conditions), and attenuation by rain;
2) positive and negative biases in retrieved wind speeds, caused by rain contamination, that are difficult to distinguish and quantify without other collocated wind data;
3) the lack of collocated rain rate data to determine the influence of rain on the retrieved wind solution;
4) ambiguity removal errors that make automated QuikSCAT-derived TC center locations unreliable, which make the determination of whether a circulation center exists in incipient systems difficult, and that require the forecaster to manually analyze the ambiguities;
5) the low frequency of passes over any given region or weather system (at most two passes per day with a single satellite) and the largest gaps between swaths in the tropics; and
6) the time lag between the satellite overpass and data receipt at NHC."
Also has a discussion about QuikScat's algorithms being unable to show a closed circulation when one was deemed present by post-storm analysis. (For all of you that incessantly dog the NHC, now you can say that just because QuikScat didn't show a closed circulation doesn't mean it isn't there.)
Finally, another point of interest that caught my eye is that QuikScat (and algorithms) repeatedly places the center of systems to the SW of the actual center.
Thank you very much Storm. :)
4 named storms
1 hurricane
0 major hurricane
And of course we can't forget our intensity model, the one, the only SHIPS! (Some How I Predict Storms). All jokes aside I do wish we could get an accurate look at 2 weeks from now. Wishful thinking, I know. Got a trip planned for Nags Head, North Carolina. Crossed fingers for sun and good fishing.
You are ahead of the game with Linux. The outbound traffic from the botnet is what is flooding the targeted sites.
They say most are in S. Korea, but they could be anywhere and folks don't know their PC is a tool for the bad guys.
This is not conflicker, it is said to be a MyDoom variant, but is basically how conflicker works. The PC's at work here number in the 60k range. Conflicker is estimated to have well over 10 million PC's at its beck and call to date.
Here is the conflicker eye chart if you want to see if you are at risk for that. Link
Q&A
El Nino has been declared many weeks before, even that will change nothing to forecasters.
Coming out of lurk to say you hit on the head Freak. It only takes one. Back to lurking.
IMO this hurricane season is going to look like this
my prediction now is
3 name storm
5 hurricane
4 major hurricane
???
That would not be a pretty picture.
I assume you are counting on CV storms?
Why are people changing their numbers on July 9th? We are not even near the peak of the season yet, look at weathersp's chart you are changing your frequency of storms on the slowest part of the season??? That makes no sense to me.
i am just kidding
Yeah. And I am hereby forecasting that most Atlantic hurricanes will have a counter-clockwise rotation, will form between 5 N and 90 N, and almost all hurricanes will have wind speeds of at least 64 knots. Oh and very few, if any, tropical systems will have a cold core.
One more, but this is a reach...all TCs will have clouds.
The woods are lovely, dark and deep,
But I have promises to keep,
And miles to go before I sleep,
And miles to go before I sleep.
LMBO!
It's not a prediction if it changes daily
That's my count, a (2004) like season, except more action either on the east Coast, or just west of Bermuda.
How can you only have 3 named storms if you are calling for 5 hurricanes? You need 5 named storms at a minimum.
LOL
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