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 Some1Has2BtheRookie:


I believe that what bappit is saying that no one individual's efforts will help to mitigate the CO2 on a global scale. When someone asks, "Well, what are you doing to mitigate the CO2?" is trolling. (Look up the definition of "blog troll")

"IF you are big into believing that man is 100% cause . then you should set an example to people who dont completely buy into it !" - This is another trollish comment. Setting examples for safe flying, swimming or driving habits are not based upon if you believe in them or not. You may not believe in them but when you do not practice them you are putting everyone within your reach at risk. When you do this on a global scale you are putting everyone on the globe at risk. .. Have you never reasoned through the thought that one should always err on the side of caution? Do you understand the ramifications when you do not do so and more than just you are being put at risk?


Asking these kinds of questions also can be a form of logical fallacy- tu quoque. Link
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Quoting AussieStorm:

Good Evening to you and TWPR and of course IRG
I'll take a big glass of Orange Juice thanks. If it freshly squeezed?


Freshly squeezed just this morning!
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Everyone have a wonderful Wednesday. Aussie, have a wonderful Thursday!
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Quoting aislinnpaps:
Morning, everyone. Evening, Aussie. 44 degrees with a wind chill of 38 here. Woke up to no internet, glad it's back on now.

Breakfast's on the sideboard. French toast with syrup, bacon and eggs, orange juice. Enjoy!

Good Evening to you and TWPR and of course IRG
I'll take a big glass of Orange Juice thanks. If it freshly squeezed?
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Good morning to all,evening Aussie.

After the dry weather that Puerto Rico has been thru for the past few weeks, some relief is comming by the weekend but will not be suficient to turn the deficit of rainfall that PR has been thru so far this year into a surplus.


AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
547 AM AST WED MAR 13 2013

.SYNOPSIS...AT MID AND UPPER LEVELS...HIGH PRESSURE WILL CROSS
THROUGH THE AREA TODAY AND INTO THE TROPICAL ATLANTIC TOMORROW. A
TROUGH WILL CROSS THROUGH THE ATLANTIC WATERS NORTH OF THE AREA
OVER THE WEEKEND WHILE HIGHER PRESSURE CONTINUES TO DOMINATE THE
SOUTHERN CARIBBEAN EARLY NEXT WEEK. THE TAIL OF A WEAK JET AND A
SHORT WAVE TROUGH IS FORECAST TO CROSS THROUGH THE AREA EARLY IN
THE FOLLOWING WEEKEND. MOISTURE AT 600 MB REMAINS BELOW 20 PERCENT
UNTIL TUESDAY NIGHT.

AT LOWER LEVELS...CLOUDS HAVE FILLED IN OVER THE AREA OVERNIGHT
BUT SHOULD DIMINISH WITH HEATING DURING THE DAY. A SHEAR LINE WILL
MOVE INTO THE AREA ON FRIDAY NIGHT OR SATURDAY AND BRING INCREASED
MOISTURE WITH A LITTLE MORE CHANCE OF RAIN...AND AS HIGH PRESSURE
FILLS IN JUST TO THE NORTH OF THE AREA NEXT WEEK THE FLOW BECOMES
EASTERLY...LEAVING THE DISSIPATING BOUNDARY OVER OR NEARBY THE
AREA WITH MODEST MOISTURE.


&&

.DISCUSSION...THE MOST PROMINENT FEATURE ON THE RADAR THIS MORNING
WAS A FIRE BURNING ABOUT 5 MILES EAST SOUTHEAST OF THE AIRPORT.
SMOKE FROM THE FIRE COULD BE SEEN MOST OF THE NIGHT AND EXTENDED
AS FAR WEST SOUTHWEST AS GUAYANILLA UNDER THE INVERSION BASED NEAR
4800 FEET AND THE CLOUDS. ABOVE THE INVERSION...TOPPED OUT AT NEARLY
6400 FEET...THE AIR WAS MOSTLY DRY. THIS HAS KEPT THE CLOUD LAYER
QUITE SHALLOW AND INCAPABLE OF CREATING SHOWERS. AS THE RIDGE OF HIGH
PRESSURE ALOFT APPROACHES AND THE SHEAR LINE MOVES SOUTHEAST THROUGH
CUBA...SHOWERS WILL BE DIFFICULT TO GENERATE...THOUGH CLOUDS WILL
FORM BETWEEN 4 TO 5 THOUSAND FEET FROM TIME TO TIME DURING THE
NEXT TWO TO THREE DAYS. THE NEXT SHEAR LINE LOOKS LIKE IT WILL
MOVE INTO THE LOCAL AREA ON SATURDAY AND STALL...LEAVING SOMEWHAT
BETTER MOISTURE AND A SLIGHT INCREASE IN SHOWER ACTIVITY. BETTER
MOISTURE IS FOUND IN THE GFS SOLUTION FOR THE WEEKEND AFTER NEXT
WITH THE APPROACH OF THE TAIL END OF A STRONG JET AND ANOTHER
SURFACE COLD FRONT.

&&

.AVIATION...VFR CONDITIONS EXPECTED ACROSS THE LOCAL TERMINALS FOR
THE NEXT 24 HOURS. BKN-OVC AT AROUND FL050 EXPECTED UNTIL
13/13Z...FEW-SCT AFTER THAT. EAST NORTHEAST WINDS BETWEEN 10 TO 15
KTS WITH SOME SEA BREEZE VARIATIONS AND A FEW HIGHER GUSTS.


&&

.MARINE...SEAS ARE EXPECTED TO DIMINISH WITH DIMINISHING SWELL
FROM THE NORTH NORTHEAST. MODELS DO NOT SHOW SEAS BELOW 7 FEET
FOR MUCH OF THE ATLANTIC AND THE CARIBBEAN PASSAGES UNTIL AFTER 8
PM AST FRIDAY. HIGH SURF CONDITIONS WILL CONTINUE THROUGH AT LEAST
THURSDAY AND WILL CONSIDER EXTENDING THE HIGH SURF ADVISORY BEFORE
7 AM AST TO INCLUDE THURSDAY THROUGH 6 PM AST.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 83 71 80 71 / 0 0 0 0
STT 84 70 83 71 / 0 0 0 20
Member Since: April 29, 2009 Posts: 75 Comments: 14279
Evening Aussie.. didn't see you about mate.

757. aislinnpaps 6:36 AM EDT on March 13, 2013

mmmm bacon :)

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Morning, everyone. Evening, Aussie. 44 degrees with a wind chill of 38 here. Woke up to no internet, glad it's back on now.

Breakfast's on the sideboard. French toast with syrup, bacon and eggs, orange juice. Enjoy!
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Quoting indianrivguy:
Morning everyone!


Evening Mate. I see Sheldon is still his arrogant best.
Opps did I say that out loud
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Morning everyone!

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Member Since: August 6, 2011 Posts: 4 Comments: 38541
Member Since: August 6, 2011 Posts: 4 Comments: 38541
Quoting Neapolitan:
In my long experience dealing with climate change, I've found one of the most common denialist tactics is to repeatedly ask, "If you believe the planet is warming, what are you doing about it?". Now, I--and others--have answered that question dozens, perhaps hundreds, of times. I myself have gone into great detail on numerous occasions with details about my lifestyle, my carbon footprint, my own conservation efforts, and so on. And every time I've done so--literally every time--the immediate denialist response has been, "You know, if you really thought climate change was happening, you'd do more." So it wasn't too long before I realized that the question was almost always being asked as a distraction, and very seldom was it asked in earnest. And since I figured that out, I've responded to it with decreasing frequency.

The thing is, if a Michael Mann or a Kevin Trenberth or a Grant Foster or a James Hansen or a Jeff Masters or a Bill McKibben does something that adds to climate change--takes a ride in a jumbo jet, say, or forgets to turn off the light when leaving the house one morning, or sets the office thermostat to 72 instead of 76 one July afternoon--that does nothing to throw the science of climate change into doubt. Nothing. There are many who will jump up and down, shout "Gotcha!!!", and claim that it does, but that doesn't make it so. So repeatedly asking a supporter of climate change theory to explain what they do to combat that change is nothing but a disingenuous--and, let's face it, very unoriginal--ploy to get them to admit to doing something that creates CO2. And for that reason, I--and many others--refuse to waste any further time answering it. We've simply got far more important things to do...


I am so glad your so smart and arrogant!
Now, I can have a good day!
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7-day for the Tampa Bay area..........
Member Since: August 6, 2011 Posts: 4 Comments: 38541
not much going on today in the southland huh...
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good morning folks!....................
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Quoting HadesGodWyvern:

I find that forecast map interesting. They expect a decoupled cyclone to intensify back to a Cat 2 before Lord Howe Island?
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747. HadesGodWyvern (Mod)
Fiji Meteorological Services
Tropical Disturbance Advisory #15
TROPICAL CYCLONE SANDRA, CATEGORY ONE (17F)
18:00 PM FST March 12 2013
=========================================

At 6:00 AM UTC, Tropical Cyclone Sandra (990 hPa) located at 24.6S 161.8E has 10 minute sustained winds of 40 knots. Position good based on multi-spectral visible imagery and peripheral surface reports.

Gale Force Winds
================
120 NM from the center in northeast quadrant
210 NM from the center in southern semi-circle
90 NM from the center elsewhere

Deep convection has decreased significantly in past 24 hours with overall organization deteriorating. Low level circulation center exposed. System lies in a high sheared environment. Sea surface temperature is around 25C. SANDRA tracking along the western periphery of the subtropical ridge positioned to the east.

Dvorak analysis based on shear pattern with low level circulation center about 66NM from dense overcast, yielding DT=2.0, PT=2.0, and MET=2.5. Final Dvorak number based on DT.

Dvorak Intensity: T2.0/3.0/W2.0/24 HRS

Most models agree on a southward movement with gradual weakening.

Forecast and Intensity
======================
12 HRS: 26.9S 161.6E - 40 knots (CAT 1/Tropical Cyclone)
24 HRS: 29.3S 161.1E - 35 knots (CAT 1/Tropical Cyclone)

This is the final tropical cyclone advisory from RSMC Nadi.. next advisory will be handled by TCWC Wellington at 14:30 PM UTC..
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746. HadesGodWyvern (Mod)
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745. HadesGodWyvern (Mod)
Tropical Cyclone Warning Center Brisbane
Tropical Cyclone Advisory
TROPICAL LOW 14U
4:47 PM EST March 13 2013
=========================================

At 4:00 PM EST, Tropical Low (997 hPa) located at 12.3S 144.4E or 130 km east northeast of Lockhart River and 535 km north northwest of Cairns has 10 minute sustained winds of 20 knots. The low is reported as moving east southeast at 13 knots.

Dvorak Intensity: T2.0/2.0/D1.0/24 HRS

Forecast and Intensity
========================
12 HRS: 13.3S 147.1E - 30 knots (Tropical Low)
24 HRS: 14.3S 149.6E - 40 knots (CAT 1/Tropical Cyclone)
48 HRS: 16.3S 154.0E - 55 knots (CAT 2/Tropical Cyclone)
72 HRS: 18.2S 155.1E - 50 knots (CAT 2/Tropical Cyclone)

Additional Information
========================
T2.0 based on poorly defined wrap of 0.3 to 0.5 over the past 6 hours with generally moderate convection. MET and PAT agree. The system lies in a region of northwest shear, though movement to the east southeast should result light system-relative shear over the next 2 to 3 days. Dry air on the southern side may also result in slowed development if it entrains into the system center.
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Quoting Levi32:


The difference is the two other periods you mentioned had low tropical activity period, whilst the recent U.S. hurricane drought has occurred amidst a rather active period in the Atlantic overall.

Yeah, there's that too. Makes me wonder if there's not some sort of unforeseen climatic signal that's altering the mean Atlantic storm track, related to AGW or otherwise.


Quoting Levi32:

And please, Sandy counts as a hurricane landfall and always will, even if not officially.


As much as Ida does.
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Quoting KoritheMan:
After mulling it over a bit in my head, I believe this is the most inactive four-year period for United States landfalls since 1990-1993. A total of 8 named storms have hit the US during the most recent 2009-2012 period (Claudette, Bonnie, Don, Irene, Lee, Beryl, Debby, and Isaac; Sandy doesn't count because she wasn't an actual hurricane), whereas a total of 5 struck the US during the previous period (1990-1993). Bonnie and Don were barely tropical cyclones at US landfall, so if we exclude them, that brings the tally up to 6 during this period. Pretty remarkable, but not without historical precedent. In addition to the aforementioned period, the 1970s were also relatively inactive US landfall wise, with only 5 such landfalls from 1972-1975.


The difference is the two other periods you mentioned had low tropical activity period, whilst the recent U.S. hurricane drought has occurred amidst a rather active period in the Atlantic overall.

And please, Sandy counts as a hurricane landfall and always will, even if not officially.
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After mulling it over a bit in my head, I believe this is the most inactive four-year period for United States landfalls since 1990-1993. A total of 8 named storms have hit the US during the most recent 2009-2012 period (Claudette, Bonnie, Don, Irene, Lee, Beryl, Debby, and Isaac; Sandy doesn't count because she wasn't an actual hurricane), whereas a total of 5 struck the US during the previous period (1990-1993). Bonnie and Don were barely tropical cyclones at US landfall, so if we exclude them, that brings the tally up to 6 during this period. Pretty remarkable, but not without historical precedent. In addition to the aforementioned period, the 1970s were also relatively inactive US landfall wise, with only 5 such landfalls from 1972-1975.
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Quoting Skyepony:
96P taking on the shape of a shrimp.








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740. HadesGodWyvern (Mod)
Tropical Cyclone Warning Center Brisbane
Tropical Cyclone Advice #3
TROPICAL CYCLONE SANDRA, CATEGORY ONE
3:01 PM EST March 13 2013
===========================================

TROPICAL CYCLONE SANDRA, CATEGORY 1, is situated over the central Coral Sea and is moving to the south. The latest forecasting guidance suggests a weak category 1 system will continue tracking south over the next 24 hours. It is then expected to re-intensify into a system with category 2 impacts during Thursday afternoon as it approaches Lord Howe Island.

Very rough seas, heavy swells and abnormally high tides are expected to develop about Lord Howe Island during Thursday and persist into Friday. This may lead to beach erosion.

Gales with damaging gusts to about 60 knots are expected to develop on Lord Howe Island during Thursday. Destructive wind gusts up to 80 knots will then possibly develop late Thursday.

Areas of heavy rain which may lead to flash flooding are also expected to develop over Lord Howe Island during Thursday and persist into Friday.

Tropical Cyclone Warnings
=============================

A Cyclone WARNING has been declared for Lord Howe Island
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Quoting Skyepony:
When the water is cooler in the the Arabian sea..

1. More moisture is present because it's raining &

2. Cooler sea has cooler air above that gets swept over the hot land of Africa causing further instability & enhanced waves..


Sandra..




Sandra is not looking to good now due to increasing shear.
Where is Sandra on this shear image....
looks like 20-30kts of shear over Sandra.


Yet the BOM has Sandra intensifying up to a Cat 2 in 24hrs.



TXPS26 KNES 130012
TCSWSP

A. 19P (SANDRA)

B. 12/2332Z

C. 23.3S

D. 161.5E

E. THREE/MTSAT

F. TOO WEAK

G. IR/EIR/VIS/SSMIS

H. REMARKS...SHEAR PATTERN GT 1.25 DEG FROM CONVECTION YEILDS A DT
OF 0.0. MET = 3.0. PT = 2.5. FT IS BASED ON RAPID WEAKENING AND IS
JUSTIFIED BY AVERAGE DT BEING LT 1.0 OVER PAST 6 HRS. THIS WILL BE THE
FINAL BULLETIN UNLESS SYSTEM REGENERATES.


I. ADDL POSITIONS

12/1845Z 22.0S 161.3E SSMIS


...GUILLOT

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738. Skyepony (Mod)
96P taking on the shape of a shrimp.


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I wish PSD Reanalysis offered correlations to Atlantic basin ACE. Guess monthly hurricane total will have to do.
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736. Skyepony (Mod)
Quoting Levi32:


Yeah, but it's hard to tell whether the shutting down of the monsoon contributes to the impact on the Atlantic, or if the Atlantic mostly responds to the ENSO itself.


I kind of think it's atleast both, plus the effects warmer Arabian Sea plays into the dust..another inhibitor.
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alright... Gnite. My pillow wants me now...
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734. HadesGodWyvern (Mod)
Tropical Cyclone Warning Center Brisbane
Tropical Cyclone Outlook
2:30 PM EST March 13 2013
========================================

A tropical low situated over the far northwest Coral Sea, near 11.9S 143.6E at 1:00 PM EST, is moving to the east southeast away from the Queensland coast. The tropical low is expected to deepen and continue moving east southeast across the Coral Sea in the next few days.

The low is likely to strengthen to tropical cyclone strength on Thursday.

There is currently no direct threat to the Queensland coast throughout the outlook period.

Tropical Cyclone Formation Potential
====================================
Thursday: HIGH
Friday: HIGH
Saturday: HIGH
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Quoting Skyepony:
ENSO is a big player too. El Nino years the high tends to shift east over India shutting down the monsoons. El Nino years we usually don't see a higher number of storms.


Yeah, but it's hard to tell whether the shutting down of the monsoon contributes to the impact on the Atlantic, or if the Atlantic mostly responds to the ENSO itself.
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732. Skyepony (Mod)
ENSO is a big player too. El Nino years the high tends to shift east over India shutting down the monsoons. El Nino years we usually don't see a higher number of storms.
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To answer (address an opinion) Doc's question in a word ....
yes

g'eve
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The 2005 Indian monsoon season was one of the wettest and most destructive on record. We know what happened with tropical cyclone activity.

The correlation does seem to be there.
Member Since: July 6, 2010 Posts: 113 Comments: 32080
Quoting AussieStorm:

Levi, is there any correlation between the strength of the Indian Monsoon and the ATL Hurricane season?


As I said, the only direct connection between the two is likely African waves, and their interaction doesn't seem to be well known yet from what I've read. It would seem to make sense that a stronger Indian monsoon would enhance African wave activity, but the question is how much.

As Tom demonstrated, historical data seems to suggest that a cooler Arabian Sea, and thus likely a stronger Indian monsoon, seems to correlate with higher Sahel rainfall.
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Quoting TomTaylor:
I'm not Levi, but in general a warm Arabian sea is a bad thing.

The top 10 ACE years all featured cooler waters in the Arabian Sea




Furthermore, the Sahel precipitation Index has a negative correlation with SSTs in the Arabian Sea. This means we want cooler SSTs there for above average Sahel precipitation.



it's like the pacific El nino... in 2009 for example, the Atlantic was below average activity while the eastern Pacific bombed... we got 180 mph Rick out of there

That's alright Tom, you're an expert at this weather matter too.
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I'll have my chart tomorrow with the new add ins..
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Quoting TomTaylor:
I'm not Levi, but in general a warm Arabian sea is a bad thing.

The top 10 ACE years all featured cooler waters in the Arabian Sea




Furthermore, the Sahel precipitation Index has a negative correlation with SSTs in the Arabian Sea. This means we want cooler SSTs there for above average Sahel precipitation.



That was the next thing I was going to check. That seems to make sense given that oceanic convection and continental convection often change at the detriment of each other. It's just that African convection and Indian convection often vary together in the summer. That's why MJO octants 2 and 3 are usually good for African waves.
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Quoting KEEPEROFTHEGATE:
Does anyone think the big one is about to hit Calf. There was a story on CNN or FOX today about all the small quakes there yesterday.
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724. Skyepony (Mod)
When the water is cooler in the the Arabian sea..

1. More moisture is present because it's raining &

2. Cooler sea has cooler air above that gets swept over the hot land of Africa causing further instability & enhanced waves..


Sandra..


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Quoting Levi32:


As far as I can tell the interactions between that region of the world and Africa are not very well known.

There is a paper (Janicot, 2009) that uses a dry primitive equation model to demonstrate a possible relationship between the Indian monsoon and Sahel convection due to monsoon waves breaking off over Asia and propagating westward over northern Africa.

However, without including interactions with deep, moist convection, the results are uncertain.

The Indian monsoon seems to me to be the only significant means by which Arabian SSTs could influence African easterly waves, it seems to be a loose connection at this point. It is also possible that warm Arabian water may reduce convection over the adjacent continent, and vice versa. The MJO is by far the biggest modulator of Africa's multi-week convective cycle.

Levi, is there any correlation between the strength of the Indian Monsoon and the ATL Hurricane season?
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Quoting trHUrrIXC5MMX:
Score card a little expanded....Still looking for anyone else who would like to join it..
9 people already!.... give it a try...!
Just tell me that you think the outcome of this season is, anyone's opinion counts!

Or go to my blog and give me your numbers...
If you want to make changes let me know as well.
Thanks to those who have already! :)



click on image for larger view.

Max, I left my thoughts and number on your blog.
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Quoting trHUrrIXC5MMX:


I have seen very strong waves over eastern Africa, some of them make their way across sometimes weaker. And they emerge into E Atl and some do develop... could we say the Arabian Sea has an influence as to waves making their way from there into Atl...besides what you estated?


As far as I can tell the interactions between that region of the world and Africa are not very well known.

There is a paper (Janicot, 2009) that uses a dry primitive equation model to demonstrate a possible relationship between the Indian monsoon and Sahel convection due to monsoon waves breaking off over Asia and propagating westward over northern Africa.

However, without including interactions with deep, moist convection, the results are uncertain.

The Indian monsoon seems to me to be the only significant means by which Arabian SSTs could influence African easterly waves, it seems to be a loose connection at this point. It is also possible that warm Arabian water may reduce convection over the adjacent continent, and vice versa. The MJO is by far the biggest modulator of Africa's multi-week convective cycle.
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Quoting aspectre:
695 gulfbreeze: Now if we could get China & India to do these things that would make a big difference!!

They'd use about 8times as much fossil fuel as they currently do.
And there'd be a heck of a lot less recycling going on.
We do not need that China is putting so much co2 in the air now but i get your point.
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719. Skyepony (Mod)
Here's a new way to go green~ divest your funds away from fossil fuels.

Taking it a step farther groups of people can divest their funds as a whole as this college just did. Behold..the power of students..

At a special meeting of College of the Atlantic’s Board of Trustees on Monday, March 11, the trustees accepted a student proposal to divest the college from all fossil fuel-related investments. The divestment of all stocks goes into effect immediately.
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Member Since: July 15, 2006 Posts: 171 Comments: 53866
717. HadesGodWyvern (Mod)
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Quoting trHUrrIXC5MMX:


I have seen very strong waves over eastern Africa, some of them make their way across sometimes weaker. And they emerge into E Atl and some do develop... could we say the Arabian Sea has an influence as to waves making their way from there into Atl...besides what you estated?
I'm not Levi, but in general a warm Arabian sea is a bad thing.

The top 10 ACE years all featured cooler waters in the Arabian Sea




Furthermore, the Sahel precipitation Index has a negative correlation with SSTs in the Arabian Sea. This means we want cooler SSTs there for above average Sahel precipitation.

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715. HadesGodWyvern (Mod)
Tropical Cyclone Warning Center Brisbane
Tropical Cyclone Advice #2
TROPICAL CYCLONE SANDRA, CATEGORY ONE
12:23 PM EST March 13 2013
===========================================

Tropical Cyclone Watches
===========================

A Cyclone WATCH has been declared for Tropical Cyclone Sandra for Lord Howe Island

TROPICAL CYCLONE SANDRA, CATEGORY 1, is situated over the central Coral Sea and is moving to the south. The latest forecasting guidance suggests a weak category 1 system will continue tracking south over the next 24 hours. It is then expected to reintensify into a system with category 2 impacts during Thursday afternoon as it approaches Lord Howe Island.

Very rough seas, heavy swells and abnormally high tides are expected to develop about Lord Howe Island during Thursday and persist into Friday.

Gales with with damaging gusts to about 110 km/hr are expected to develop on Lord Howe Island during Thursday. Destructive wind gusts up to 150km/hr will then possibly develop late Thursday.

Areas of heavy rain which may lead to flash flooding are also expected to develop over Lord Howe Island during Thursday and persist into Friday.
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Quoting Levi32:


It has a very strong positive correlation with ENSO, but I'm not sure what else. It may affect the Indian monsoon circulation, which may affect African easterly waves, but I have not researched it much.


I have seen very strong waves over eastern Africa, some of them make their way across sometimes weaker. And they emerge into E Atl and some do develop... could we say the Arabian Sea has an influence as to waves making their way from there into Atl...besides what you estated?
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Quoting Gearsts:
What implication does the arabian sea SST have on the atlantic for hurricane season?


It has a very strong positive correlation with ENSO, but I'm not sure what else. It may affect the Indian monsoon circulation, which may affect African easterly waves, but I have not researched it much.
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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.