Are atmospheric flow patterns favorable for summer extreme weather increasing?

By: Dr. Jeff Masters , 2:45 PM GMT on March 11, 2013

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In 2010, Russia baked through its most intense heat wave in recorded history, one that killed over 55,000 people. At the same time, intense rains deluged Pakistan, bringing that nation its worst natural disaster in its history. The following year, it was the United States' turn for extreme heat, as the nation sweltered through its third hottest summer on record, and Oklahoma suffered the hottest month any U.S. state has ever recorded. The U.S. summer of 2012 was even more extreme. Only the Dust Bowl summer of 1936 was hotter, and drought conditions were the most extensive since the 1930s. All of these events--and many more unusually extreme summer months in recent decades--had a common feature, said scientists at the Potsdam Institute for Climate Impact Research (PIK) in Germany, in a research paper published in March 2013 in Proceedings of the National Academy of Sciences. According to the authors, "each time one of these extremes struck, a strong wave train had developed in the atmosphere, circling the globe in mid-latitudes. These so-called planetary waves are well-known and a normal part of atmospheric flow. What is not normal is that the usually moving waves ground to a halt and were greatly amplified during the extreme events. Looking into the physics behind this, we found it is due to a resonance phenomenon. Under special conditions, the atmosphere can start to resonate like a bell. The wind patterns form a regular wave train, with six, seven or eight peaks and troughs going once around the globe". Using a complex theoretical mathematical description of the atmosphere and 32 years of historical weather data, the scientists showed that human-caused global warming might be responsible for this resonance phenomenon, which became twice as common during 2001 - 2012 compared to the previous 22 years.


Figure 1. Drought-damaged corn in a field near Nickerson, Nebraska, Aug. 16, 2012. The great U.S. drought of 2012 was the most extensive U.S. drought since the 1930s Dust Bowl. Damage from the 2012 drought is at least $35 billion, and probably much higher. The associated heat wave killed 123 people, and brought the U.S. its second hottest summer on record. (AP Photo/Nati Harnik)


Figure 2. Business was slow at the Lake Conroe, Texas jet ski rental in 2011, thanks to the great Texas drought and heat wave of 2011. Texas endured its driest 1-year period on record in 2011, and had the hottest summer ever recorded by a U.S. state. July 2011 in Oklahoma was the hottest month any U.S. state has ever recorded, and the contiguous U.S. had its third hottest summer on record. The total direct losses to crops, livestock and timber from the drought, heat wave, and record fires of the summer of 2011 are estimated at $12 billion, with a death toll of 95. Image credit: wunderphotographer BEENE.


Figure 3. Tourists wear protective face masks as they walk along the Red Square in Moscow, Russia on Aug. 6, 2010. Moscow was shrouded by a dense smog that grounded flights at international airports and seeped into homes and offices, due to wildfires worsened by the city's most intense heat wave in its history. The heat wave and fires during the summer of 2010 killed over 55,000 people in Russia and decimated the Russian wheat crop, causing global food prices to spike. (AP Photo/Mikhail Metzel)

Two fundamental atmospheric flow patterns may be resonating more often due to global warming
Earth's atmosphere has two fundamental patterns. One is a series of wave-like troughs and ridges in the jet stream called planetary (or Rossby) waves, which march west-to-east at about 15 - 25 mph around the globe. The other pattern behaves more like a standing wave, with no forward motion, and is created by the unequal heating of the equatorial regions compared to the poles, modulated by the position of the continents and oceans. A number of papers have been published showing that these two patterns can interact and resonate in a way that amplifies the standing wave pattern, causing the planetary waves to freeze in their tracks for weeks, resulting in an extended period of extreme heat or flooding, depending upon where the high-amplitude part of the wave lies. But what the Potsdam Institute scientists found is that because human-caused global warming is causing the Arctic to heat up more than twice as rapidly as the rest of the planet, the two patterns are interacting more frequently during the summer. During the most recent eleven years, 2002 - 2012, there were eight Julys and Augusts that showed this unusually extreme resonance pattern (this includes the U.S. heat wave of July - August 2012.) The two previous eleven year periods, 1991 - 2001 and 1980 - 1990, had just four extreme months apiece. Global warming could certainly cause this observed increase in the resonance phenomenon, but the researchers cautioned, "The suggested physical process increases the probability of weather extremes, but additional factors certainly play a role as well, including natural variability. Also, the 32-year period studied in the project provides a good indication of the mechanism involved, yet is too short for definitive conclusions. So there's no smoking gun on the table yet--but quite telling fingerprints all over the place."



Figure 4. The northward wind speed (negative values, blue on the map, indicate southward flow) at an altitude of 300 mb in the mid-latitudes of the Northern Hemisphere during July 2011 and July 1980. July of 2011 featured an unusually intense and long-lasting heat wave in the U.S., and the normally weak and irregular waves (like observed during the relatively normal July of 1980) were replaced by a strong and regular wave pattern. Image credit: Vladimir Petoukhov.

Commentary
The new Potsdam Institute paper gives us a mathematical description of exactly how global warming may be triggering observed fundamental changes in large-scale atmospheric flow patterns, resulting in the observed increase in unusually intense and long-lasting periods of extreme weather over the past eleven years. The paper also adds important theoretical support to the research published in 2012 by Dr. Jennifer Francis of Rutgers University, which found that the amplitude of Earth's planetary waves had increased by over 100 miles (161 km) in summer over the past decade in the Northern Hemisphere. Dr. Francis theorized that this change was connected to increased heating of the Arctic relative to the rest of the Earth, due to the observed decline in late spring Northern Hemisphere snow cover. Humans tend to think linearly--one plus one equals two. However, the atmosphere is fundamentally non-linear. What may seem to be modest changes in Earth's climate can trigger unexpected resonances that will amplify into extreme changes--cases where one plus one equals four, or eight, or sixteen. In some cases, when you rock the boat too far, it won't simply roll a bit more, it will reach a tipping point where it suddenly capsizes. Similarly, human-caused global warming is capable of pushing the climate past a tipping point where we enter a new climate regime, one far more disruptive than what we are used to.

Julys and Augusts since 1980 when quasiresonant extreme conditions were observed
The Potsdam Institute's research lists sixteen July and August periods since 1980 that have had extreme atmospheric flow patterns due to quasiresonance. These months featured severe regional heat waves and destructive floods in the Northern Hemisphere midlatitudes, detailed below. Half of these months occurred in the most recent 11-year period, 2002 - 2012. During most of these extreme months, there was not a moderate or strong La Niña or El Niño event contributing to the extremes. Summers when a La Niña or El Niño event was present are listed in parentheses, based on the Oceanic Niño Index (ONI).

July and early August 2012: Catastrophic floods in China and Japan, as well as record-breaking temperatures during heat waves in the United States and southern Europe (weak summer El Niño)

July 2011: Record heat wave in the United States, resulting in the fourth warmest July on record nationally and the driest conditions in the southern United States ever (weak summer La Niña)

July/August 2010: Russian heat wave and the Pakistan flood, with the strongest and most persistent extreme weather conditions and the highest death tolls from heat waves and floods ever for these two regions (strong summer La Niña)

July 2006: Temperatures higher than 100°F for only the second time in Britain’s history and much of Europe experiencing a serious heat wave (weak summer El Niño)

August 2004: Much of northern Europe hit by very low winter-like temperatures and sporadic snowfalls (moderate to strong summer El Niño)

August 2003: European summer 2003 heat wave, causing a highly persistent drought in western Europe (weak summer El Niño)

August 2002: Catastrophic Elbe and Danube floods (strong summer El Niño)

July 2000: Destructive floods in northern Italy and the Tisza basin and a simultaneous heat wave in the southern United States, smashing all-time high-temperature records by that time at many sites (strong summer La Niña)

July/August 1997: Disastrous Great European Flood, which caused several deaths in central Europe, and the destroying floods in Pakistan and western United States (strong summer El Niño)

July 1994: Very strong heat wave in southern Europe, with a national temperature record of 47.2°C set in Spain (weak summer El Niño)

July 1993: Unprecedented great flood in the United States that reigned over the country from April (weak summer El Niño)

July 1989: Unusually intense and unprecedented widespread drought in the United States (weak summer La Niña)

August 1987: Severe drought in the southeastern United States (strong summer El Niño)

August 1984: Continuation of the severe heat of summer 1983, with serious drought in the United States (weak summer La Niña)

July and August 1983: Very dry conditions, severe heat, and substandard crop growth (5–35% below normal) in the Midwest United States (weak summer El Niño)

Links
Petoukhov, V., Rahmstorf, S., Petri, S., Schellnhuber, H. J. (2013), "Quasi-resonant amplification of planetary waves and recent Northern Hemisphere weather extremes" Proceedings of the National Academy of Sciences, (Early Edition) [doi:10.1073/pnas.1222000110]. No subscription required, but understanding this article requires a graduate-level understanding of the mathematical theory of atmospheric dynamics. Try reading instead this easy-to-read description of the paper by the authors, published at http://theconversation.edu.au.

Press release issued in March 2013 by the Potsdam Institute for Climate Impact Research (PIK), "Weather extremes provoked by trapping of giant waves in the atmosphere."

In this 40-minute lecture presented in 2013 at the University of Arkansas, Dr. Jennifer Francis of Rutgers University explains the linkage between warming in the Arctic due to human-caused global warming and an observed shift in Northern Hemisphere jet stream patterns.

Linking Weird Weather to Rapid Warming of the Arctic, a March 2012 article by Dr. Jennifer Francis in the Yale Environment 360.

Francis, J.A., and S.J.Vavrus, 2012, "Evidence linking Arctic amplification to extreme weather in mid-latitudes", GEOPHYSICAL RESEARCH LETTERS, VOL. 39, L06801, doi:10.1029/2012GL051000, 2012

Jeff Masters

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Quoting StormTrackerScott:
El-Nino may be on the rebound. Nino 1&2 are up to .04 and Nino 3 is up to .01


The MJO is in the western Pacific so warming is to be expected. We may see a return of warm Neutral by the end of this month, but an El Niño is just as likely as a La Niña at this point--that is, very unlikely.

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Lee Sandlin, author of "Storm Kings: The Untold Story Of America's First Tornado Chasers" and Harold Brooks, research meteorologist at NOAA's National Severe Storms Laboratory were interviewed on WAMU's Diane Rehm Show today. The interview is not very technical, but has some interesting stories about tornado encounters and tornado history.

Audio link and book excerpt can be found here.
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So everyone is talking about the '93 superstorm... are the models suggesting a repeat of this, or is all the chat just due to the anniversary coming up?
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Quoting KEEPEROFTHEGATE:


Early reports of 5.0 mag Qada'Talkif, Iran..
Member Since: August 13, 2009 Posts: 13 Comments: 6877
Actually July and August 1980 were extremely hot with an almost unbreaking stuck ridge in the southern half of the U.S. 1980 and 1983 were the worst "Death Dome" summers (after the 1950s and 1930s) until the second decade of the 21'st century. 1988 started worse but the ridge broke in late summer. And 1980 was remarkable for extreme persistence of that ridge, perhaps the worst of any summer
of record. It was not notably hot in the northern third of the U.S in
contrast to summers of the 30s, 50s and this century

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Quoting LargoFl:
just look at the sheer size of that monster in 1993...


The lightning from that system was insane as it moved thru Seminole County. At my house there were many trees down as the squall line came thru. Also a tornado hit 10 minutes west of me. That tornado was rated F3 to F4.
Member Since: February 28, 2013 Posts: 7 Comments: 3754
Floridians will never forget 1993.............Along Florida's Gulf Coast, the no-name storm damaged or destroyed 18,000 homes and caused more than $500-million in property damage, more than double that of Hurricane Elena in 1985. Statewide, it killed at least 26 people, more than Hurricane Andrew. Among the dead: six members of one family, washed away as they attended a reunion.
Member Since: August 6, 2011 Posts: 4 Comments: 40832
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Thanks Doc,
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Quoting LargoFl:
just look at the sheer size of that monster in 1993...


Key is it took the southern route, which makes these systems powerful.

Notice the cold air pouring over the entire GOM causing the low clouds

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I remember flying home (at the time) to Wisconsin from Tampa the day after the front went through. Sunshine bridge was closed due to high winds. Even though winds were extremely high, they were from one direction, so no problems taking off into it. Was actually one of the smoothest and most rapid ascents I have experienced.
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U.S. summer of 2012 was even more extreme. Only the Dust Bowl summer of 1936 was hotter, and drought conditions were the most extensive since the 1930s.

A question - do we have any idea how pronounced quasiresonance was during the Dust Bowl era? Or is this something we have only been able to measure with any accurancy in the more-recent satellite era?
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just look at the sheer size of that monster in 1993...
Member Since: August 6, 2011 Posts: 4 Comments: 40832
El-Nino may be on the rebound. Nino 1&2 are up to .04 and Nino 3 is up to .01

Member Since: February 28, 2013 Posts: 7 Comments: 3754
Member Since: August 6, 2011 Posts: 4 Comments: 40832
My mom was at UGA during the blizzard....
She has pictures of parking lots with 8" of snow.
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storm of the century..............Link
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Quoting LargoFl:
I have to say, that was the very first time I boarded up the windows and was for the first time in florida i was scared..that storm was a monster,my area got spared somewhat when it went in further north of us into the nature coast but for awhile there it sure looked like i was going to get whacked big time..from then on, i closely followed each storm in the gulf heading anywhere near florida...a monster it was.


I remember over in Florida, it was spring training and the Astros Jeff Bagwell and Craig Biggio was interviewed and they were saying the sky was a tint greenish blue at night when it plowed into there, major damage to the ballparks, light poles down at the parks, was crazy.
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Quoting FtMyersgal:


How low did the pressure get?


By early afternoon on March 13th the central pressure of the low was lower than had been observed with any historic winter storm or hurricane across the interior Southeastern United States. All-time low pressure records were established in Columbia, Charlotte and Greensboro, even beating out the pressures observed just a few years earlier during Hurricane Hugo's visit in September 1989.
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for the 93 Storm, here in Eastern NC, we got ICE! Power lines and car motors frozed up. I had come home for the weekend for college and couldnt return to school until a week later. I discovered kerosene heaters during that time as we had no fireplace. You couldnt travel anywhere and most all stores were closed..It was awful because it was so bitter cold and there was no heat.
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Quoting RitaEvac:


Yea I remember hearing about the storm surge going into Florida, that was crazy, that's how powerful that low pressure was and how strong the winds were.
I have to say, that was the very first time I boarded up the windows and was for the first time in florida i was scared..that storm was a monster,my area got spared somewhat when it went in further north of us into the nature coast but for awhile there it sure looked like i was going to get whacked big time..from then on, i closely followed each storm in the gulf heading anywhere near florida...a monster it was.
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Quoting FtMyersgal:


How low did the pressure get?


Don't remember, sure google has that info
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Quoting RitaEvac:


Yea I remember hearing about the storm surge going into Florida, that was crazy, that's how powerful that low pressure was and how strong the winds were.


How low did the pressure get?
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See how much Nino 3.4 warmed in the CPC 3/11/13 Update at my blog.
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Quoting LargoFl:
The '93 Superstorm. The Storm of the Century. The Great Blizzard of 1993. The No-Name Storm.

These are all monikers for the storm that holds the record as the worst winter storm in U.S. history. And while the storm has no official title in Florida, it has accurately been dubbed the Storm of the Century in and out of our state.

The Storm of the Century affected 40 percent of the nation's population, dumping snow from Mobile, Ala., to the Florida Panhandle and also from Chicago to Nova Scotia.

The March 12, 1993 storm killed more than 300 people - three times more than hurricanes Hugo and Andrew combined, whipped Cuba with 130 mph winds and shut down every major airport along the U.S. east coast.

It killed 44 people in Florida - 28 directly during the storm. Damages totaled $1.6 billion in Florida alone, with 18,000 homes destroyed and 11 confirmed tornadoes. The storm also established a permanent place in memories of longtime Floridians and the history books.

"Why was this thing so deadly?" said Bay News 9 Chief Meteorologist Mike Clay. "I think a lot of people did not believe how bad it was going to be. No one had ever seen a storm surge from a winter storm in the Gulf of Mexico like that.

"So it was beyond the realm of thinking for meteorologists at that time."


Yea I remember hearing about the storm surge going into Florida, that was crazy, that's how powerful that low pressure was and how strong the winds were.
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Thanks Doc!
Member Since: September 16, 2010 Posts: 0 Comments: 1219
The '93 Superstorm. The Storm of the Century. The Great Blizzard of 1993. The No-Name Storm.

These are all monikers for the storm that holds the record as the worst winter storm in U.S. history. And while the storm has no official title in Florida, it has accurately been dubbed the Storm of the Century in and out of our state.

The Storm of the Century affected 40 percent of the nation's population, dumping snow from Mobile, Ala., to the Florida Panhandle and also from Chicago to Nova Scotia.

The March 12, 1993 storm killed more than 300 people - three times more than hurricanes Hugo and Andrew combined, whipped Cuba with 130 mph winds and shut down every major airport along the U.S. east coast.

It killed 44 people in Florida - 28 directly during the storm. Damages totaled $1.6 billion in Florida alone, with 18,000 homes destroyed and 11 confirmed tornadoes. The storm also established a permanent place in memories of longtime Floridians and the history books.

"Why was this thing so deadly?" said Bay News 9 Chief Meteorologist Mike Clay. "I think a lot of people did not believe how bad it was going to be. No one had ever seen a storm surge from a winter storm in the Gulf of Mexico like that.

"So it was beyond the realm of thinking for meteorologists at that time."
Member Since: August 6, 2011 Posts: 4 Comments: 40832
Quoting GeorgiaStormz:


I hear it was great.
Unfortunately I had no chance of seeing it


I remember waking up to a roar, and we all were tuned in to the TWC and saw radar of a large thick orange red line moving in, it was already way behind because radar was showing it NW of us, and the line had already blasted thru us outside, so that line must of been moving some 50mph SE. That's my estimate. Remember limbs down, branches down, was wild...and that was only just the beginning of the actual storm.
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34. Skyepony (Mod)
Dr Masters~ Great blog, though I think more than just the hotter Arctic/less heat difference is playing into this.. With the loss of Arctic Sea Ice getting to the point where Greenland & just north of there has become the one remaining frozen spot, this has caused the center high that all the lows & waves undulate around to become stagnant & stuck to Greenland. This used to traipse the whole Arctic frozen multi-year sea ice through out the summer. Without the center moving about, wobbling around the Arctic~ the waves don't get that added movement or whip, which in turn adds to the quasiresonance.

Here's the anomaly for jul & aug of last year.. The trend holds pretty much like this for the whole melt season but is most amplified these two months.
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Quoting GeorgiaStormz:


I hear it was great.
Unfortunately I had no chance of seeing it


In my case I was almost 4 months old... no chance at all!
:(
Member Since: April 23, 2011 Posts: 104 Comments: 14873
Storm of the Century just about 20 yrs later.......
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Quoting RitaEvac:
I remember that squall line in 93'coming in during the middle of night in SE TX, woke the whole family up, which was extremely rare for all of us to be up, wind was roaring. Too bad there isn't a radar archive out there of that.





I hear it was great.
Unfortunately I had no chance of seeing it
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Quoting goosegirl1:


Nor'easter I can handle, as long as it doesn't snow again :)


for sure...so can I....

What I can't are storms like Nemo...
Member Since: April 23, 2011 Posts: 104 Comments: 14873
Quoting StormTrackerScott:
It looks as if March is going to go out with a BANG this year. Very interested in seeing the 12Z GFS later today.


Nor'easter I can handle, as long as it doesn't snow again :)
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That 93' storm was one of the most memorable squall lines ever that I can recall, there hasn't ever been one close to it ever.
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I remember that squall line in 93'coming in during the middle of night in SE TX, woke the whole family up, which was extremely rare for all of us to be up, wind was roaring. Too bad there isn't a radar archive out there of that.



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Wow.. gonna take a while to digest this one... some new vocabulary too.. hmmm.. maybe we should start naming winter storms meteorology terms instead of well, what they are using now.. that way people could actually learn something useful, sic. "Winter Sotrm Quasiresonance is heading toward the North East and expected to bring high winds and at least 4 inches of wet snow later tomorrow evening..."
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resembles yesterday afternooon ecmwf

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@ GA...

Great job with that!
Member Since: April 23, 2011 Posts: 104 Comments: 14873
it moved on:



to the next day










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Quoting GeorgiaStormz:
blizzard of 93 beginnings:


do you find a correlation between the 93 and this upcoming "possible" nor'easter?
Member Since: April 23, 2011 Posts: 104 Comments: 14873
Quoting StormTrackerScott:
It looks as if March is going to go out with a BANG this year. Very interested in seeing the 12Z GFS later today.
I haven't had a chance to see it yet since I'm at work. Mind describing what it shows?
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blizzard of 93 beginnings:
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Did You Know? #Sandy generated 30 million weather tweets.

At #tornadosummit learning about social media & severe weather
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Quoting Waltanater:
...resonation :)


TY.. :)
Member Since: August 13, 2009 Posts: 13 Comments: 6877
Big rain wed (it's not today)...I'll be using one of my new maps later today. Can't wait to get out of work get started..

Member Since: April 23, 2011 Posts: 104 Comments: 14873
Thanks for the entry Dr. Masters.
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I hope for some DECENT rains and tropical waves this year!!! The Leewards are so dry...
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Thanks Doc.
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Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.

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