Modiki El Niños and Atlantic hurricane activity

By: Dr. Jeff Masters , 1:48 PM GMT on July 08, 2009

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


The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.

Reader Comments

Display: 0, 50, 100, 200 Sort: Newest First - Order Posted

Viewing: 43 - 1

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 — Blog Index

It really, really, really needs to stop raining in Florida and spread some of it around. Just wont stop raining.
Member Since: December 31, 1969 Posts: Comments:
Quoting Weather456:


A google earth file, I had.

The code in the file says 20090707

The website itself is giving problems.

Google Earth file
Link
Member Since: Posts: Comments:
Quoting btwntx08:
woah interesting blob off the belize and yucatan area


Definately interesting for the time being. I'll be keeping an eye on oit throughout the day.
Member Since: Posts: Comments:
Good Morning,

Looks like the wave at about 20W is still together. Also, looks live some waves lined up on the African continent.
Member Since: Posts: Comments:
Quoting HurrikanEB:
How have the other basins been doing this year. I've been following the East Pacific and obviously the Atlantic, but what about the West Pacific and the Indian Oceans?


Surprisingly, progression is low in the EPAC and WPAC since we should be up to 4 named storms in the EPAC and even more in the WPAC.

Only the Atlantic seems near the long-term average.

The N Indian Ocean normally sees 4-6 named storms a year, they already have 2 and they have another peak in October/November this year.
Member Since: December 31, 1969 Posts: Comments:
4 FIVEPOINTO "So whats going on with the Sea ice up north?"

More ice coverage than in early July during the record melt of 2007, but less coverage than in early July of 2005 (which had held the melt record prior to 2007)

from the NationalSnow&IceDataCenter's monthly Arctic sea ice news brief.
Member Since: Posts: Comments:
How have the other basins been doing this year. I've been following the East Pacific and obviously the Atlantic, but what about the West Pacific and the Indian Oceans?
Member Since: Posts: Comments:
You can get TCHP here. I have not been able to figure out how to display the scale yet.
Member Since: December 31, 1969 Posts: Comments:
Reminding me of 98' hot/dry June July, then 2 tropical storms hit TX August September

Charley and Frances, nice drought busters
Member Since: Posts: Comments:
Skyepony, its hard to interpret the fire item due to the arson variable that was in play with many of the fires.
Member Since: December 31, 1969 Posts: Comments:
Quoting Skyepony:
456~ where did you find the updated TCHP map? All I've seen are stuck on May 19th.


A google earth file, I had.

The code in the file says 20090707

The website itself is giving problems.
Member Since: December 31, 1969 Posts: Comments:
From yesterday's Monthly Ocean Briefing


Member Since: December 31, 1969 Posts: Comments:
according to those TCHP map, I am afraid to think about a Cane getting into the gulf... The GOM has higher TCHP then 05..eeek! lol! :)
Member Since: Posts: Comments:
30. IKE
Quoting CaneWarning:


Are you talking to yourself? With 72 on your ignore list I doubt you see too many of us!


These go back a few years. I've just never deleted one's from at least 2 years ago.
Member Since: December 31, 1969 Posts: Comments:
I've got 96 people on mine, all of them trolls from the past 3 years.
Member Since: December 31, 1969 Posts: Comments:
28. IKE
Quoting TheWeatherMan504:


I call it the Troll List.


He needs to go mow his yard...wash his car...a wound up person.

Interesting blog Dr. Master's. It's not just that there is an El Nino, it's where it's at in the Pacific ocean.

Shear rules!
Member Since: December 31, 1969 Posts: Comments:
WOW!I step into the blog and the drama awaits...
Member Since: Posts: Comments:
26. Skyepony (Mod)
456~ where did you find the updated TCHP map? All I've seen are stuck on May 19th.
Member Since: Posts: Comments:
Its a wait and see scenario.
I can predict this though,
Tropical cyclone development is not expected in the next 24 hours. Nothing really out there of note, and it might stay that way for a few weeks.
Member Since: December 31, 1969 Posts: Comments:
Quoting IKE:
Ah...I feel better.

72 on ignore now.


Are you talking to yourself? With 72 on your ignore list I doubt you see too many of us!
Member Since: December 31, 1969 Posts: Comments:
23. Skyepony (Mod)
Looking at it a little closer there may not be much a corrilation with the FL fire season. '83 was more a central FL event & There's other events that didn't occur anywhere around El nino years.
Member Since: Posts: Comments:
Quoting IKE:
Ah...I feel better.

72 on ignore now.


I call it the Troll List.
Member Since: Posts: Comments:
Quoting FIVEPOINTO:
So whats going on with the Sea ice up north?


As of 5 days ago (should be updated later today)

Link
Member Since: Posts: Comments:
Slow start to season is the only basis for much predictions during the peak. Weird. I still have my hurricane kit on standby, and not puttin it away until December.

July 9 2005



July 7 2009

Member Since: December 31, 1969 Posts: Comments:
People should stop taking Dr. Masters word as god. No offense to him, as he is a great meteorologist and ive learned much from him, but don't be relieved just because the Dr. says it should be a slow hurricane season, weather is weird anything can happen. That is when people let their guard down and become unprepared when/if the big one does come.
Member Since: Posts: Comments:
Doc, what impact do you feel the current movement to El Niño is having on the modeling ?
Member Since: December 31, 1969 Posts: Comments:
17. IKE
Ah...I feel better.

72 on ignore now.
Member Since: December 31, 1969 Posts: Comments:
I would hedge my bets on an Modiki El Niño. Thus far, it appears westerly wind bursts have been making it to the dateline and little further, with near-average trades from 140°W on east.

These Modiki El Niño's are also the weaker of the two and the current sub-surface anomalies and thermocline suggests that this won't be a mind blowing El Niño event. It's also noteworthy that AAM has been dipping over the last 2 weeks, likely slowing down our progression towards El Niño over the next couple of weeks.

El Niño is really interesting study, especially the way it correlates to Atlantic hurricane activity. As this new study shows, the spatial pattern of SST anomalies associated with ENSO events has an additional moderating factor on Atlantic tropical cyclone activity.

Digging a bit further, I bet there's a nice correlation between TanomMDR-TanomNINO3+Nino(1+2)/TanomNINO4.
Member Since: Posts: Comments:
Check this out. It's a long range computer model that goes all the way to April 2010, and it has pretty good accuracy.
Member Since: Posts: Comments:
Quoting btwntx08:
woah interesting blob off the belize and yucatan area


thunderstorms, nothing more, nothing less
Member Since: Posts: Comments:
Using cellphone relay towers as hygrometers by translating microwave-strength data into moisture measurements to predict rainfall and flooding.
Member Since: Posts: Comments:
9. Skyepony (Mod)
Great blog Jeff. Interesting the EPW events occurred the year before FL had it's worst fire seasons in recent years. 1998 & '83 were really bad state burning events, & '88 was memorable as well.
Member Since: Posts: Comments:
Quoting FIVEPOINTO:
So whats going on with the Sea ice up north?


WU Climate Change Webpage
Member Since: December 31, 1969 Posts: Comments:
it could be a coincidence... i mean the 1991 and 1994, pictures show an average el nino hurricane season, heck 1997 was more intense then 1994. There may not be a correlation at all.
Member Since: Posts: Comments:
Quoting IKE:
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.

Good...great news.

So my belated prediction of 10-4-2 may be too high.


I would be surprised if we hit those numbers... the interesting part..if I am reading what Weather456 is saying... its not a good omen for next year.

Blog Update
Member Since: December 31, 1969 Posts: Comments:
Thx Doc for the educational info....
Member Since: December 31, 1969 Posts: Comments:
So whats going on with the Sea ice up north?
Member Since: Posts: Comments:
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.

Good...great news.

So my belated prediction of 10-4-2 may be too high.
Member Since: December 31, 1969 Posts: Comments:
Very interesting. But it seems classic so far

Member Since: December 31, 1969 Posts: Comments:
There will be a monster in the carribbean.
Terrible.
Member Since: Posts: Comments:

Viewing: 43 - 1

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 — Blog Index

Top of Page

Category 6™

About

Cat 6 lead authors: WU cofounder Dr. Jeff Masters (right), who flew w/NOAA Hurricane Hunters 1986-1990, & WU meteorologist Bob Henson, @bhensonweather