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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JRRP knew exactly what he/she was doing.
Well I am going to stick with this one throughout the season
Yea, I saw that. What's worse is his sidekick will be Stephanie Abrams. I'd rather watch a cable-access weather show than that duo.
i know :P
Abrams and Roker. Talk about an *obnoxious* way to wake up in the morning. BLECH! Roker is going to be a big embarrasement to the real mets that work there.
http://www.nco.ncep.noaa.gov/pmb/nwprod/analysis/carib/gfs/12/model_l.shtml
I will respect your opinion as long as you stick with it and aren't always changing it... remeber what you just said..
Alberto 2000
Andrew 1992
Allen 1980
and 1998...1969 as well
Anna 1969
Link
Is that somehow going to make TWC any less useful than it already is? They could have Barney on and it wouldn't change my current opinion of it.
Cape Verde Hurricanes, a very unique term as it does not consider tropical storms.
1967- Arlene didn't form until August 28th!
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Link
Can I make a suggestion? For all of you that get your panties in a bunch about someone whom you've ignored being quoted - change your avatar to be a screen capture of your ignored list. That way we'll ALL know who you've ignored and we will still quote people whom we want to anyway. But -- at least you'll know you've done all you can and not have to make yet another post about it.
(Crap. I'll probably get yelled at now for quoting someone on someone else's ignore list.)
El Nino conditions are now firmly in control in the EPAC with water temps 1.8 degrees above normal. This could mean an August start to the season shaping up as the El Nino is forecasted to strengthen further.
El Nino returns
It is little blessing to have a Forecast of 3 Hurricanes in the Season and then u are unfortunate enough to get hit by one that may be Cat 3 and above - it only takes one to "ruin your day" (and many more days thereafter). I suppose in a quiet period it provides subject for discussion and overall keeps those statisticians happy - for me - I want zero Hurricanes anywhere this Season.
And here he is doing the weather on location:
Nope. Just a dry delay.
I just saw a report on tv that El Nino has arrived.
By some, yes. But don't worry though, becuz those same ones will running back the first news break that Ana has arrived.
Neil Armstrong speaks at the dedication of the new 'Neil Armstrong Hall of Engineering' at Purdue. Attending are most of the astronauts that graduated from Purdue as well as Gene Cernan.
http://www.ssd.noaa.gov/eumet/eatl/rb-l.jpg
Recurving Vs Landfalling Cape Verde Hurricanes
No, last time I saw Al on tv he was talking about a doughnut he had eaten. I don't watch TWC anymore hardly.
12Z shows a quite a little bugger out there in a week.
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Model Cycle: 2009070912
North America: Model Tracks for Mid-Latitude Cyclones
..."Nuthing"...
At least your date wasn't in the first week of June...
When I was working on Project Runway we did an episode at the Today Show. Poor Al was limping out to his car after the show. He has really gained wieght since his bariatric surgery. I thought it was sad.
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