Hurricane Sandy's huge size: freak of nature or climate change?

By: Dr. Jeff Masters , 1:10 PM GMT on November 13, 2012

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Hurricane Sandy was truly astounding in its size and power. At its peak size, twenty hours before landfall, Sandy had tropical storm-force winds that covered an area nearly one-fifth the area of the contiguous United States. Since detailed records of hurricane size began in 1988, only one tropical storm (Olga of 2001) has had a larger area of tropical storm-force winds, and no hurricanes has. Sandy's area of ocean with twelve-foot seas peaked at 1.4 million square miles--nearly one-half the area of the contiguous United States, or 1% of Earth's total ocean area. Most incredibly, ten hours before landfall (9:30 am EDT October 30), the total energy of Sandy's winds of tropical storm-force and higher peaked at 329 terajoules--the highest value for any Atlantic hurricane since at least 1969. This is 2.7 times higher than Katrina's peak energy, and is equivalent to five Hiroshima-sized atomic bombs. At landfall, Sandy's tropical storm-force winds spanned 943 miles of the the U.S. coast. No hurricane on record has been wider; the previous record holder was Hurricane Igor of 2010, which was 863 miles in diameter. Sandy's huge size prompted high wind warnings to be posted from Chicago to Eastern Maine, and from Michigan's Upper Peninsula to Florida's Lake Okeechobee--an area home to 120 million people. Sandy's winds simultaneously caused damage to buildings on the shores of Lake Michigan at Indiana Dunes National Lakeshore, and toppled power lines in Nova Scotia, Canada--locations 1200 miles apart!

Largest Atlantic tropical cyclones for area covered by tropical storm-force winds:

Olga, 2001: 780,000 square miles
Sandy, 2012: 560,000 square miles
Lili, 1996: 550,000 square miles
Igor, 2010: 550,000 square miles
Karl, 2004: 430,000 square miles



Figure 1. Hurricane Sandy’s winds (top), on October 28, 2012, when Sandy was a Category 1 hurricane with top winds of 75 mph (this ocean surface wind data is from a radar scatterometer on the Indian Space Research Organization’s (ISRO) Oceansat-2.) Hurricane Katrina’s winds (bottom) on August 28, 2005, when Katrina was a Category 5 hurricane with top winds of 175 mph (data taken by a radar scatterometer on NASA’s defunct QuickSCAT satellite.) In both maps, wind speeds above 65 kilometers (40 miles) per hour are yellow; above 80 kph (50 mph) are orange; and above 95 kph (60 mph) are dark red. The most noticeable difference is the extent of the strong wind fields. For Katrina, winds over 65 kilometers per hour stretched about 500 kilometers (300 miles) from edge to edge. For Sandy, winds of that intensity spanned an region of ocean three times as great--1,500 kilometers (900 miles). Katrina was able to generate a record-height storm surge over a small area of the Mississippi coast. Sandy generated a lower but highly destructive storm surge over a much larger area, due to the storm's weaker winds but much larger size. Image credit: NASA.

How did Sandy get so big?
We understand fairly well what controls the peak strength of a hurricane's winds, but have a poor understanding of why some hurricanes get large and others stay small. A number of factors probably worked together to create a "prefect storm" situation that allowed Sandy to grow so large, and we also must acknowledge that climate change could have played a role. Here are some possible reasons why Sandy grew so large:

1) Initial size of the disturbance that became Sandy was large
Sandy formed from an African tropical wave that interacted with a large area of low pressure that covered most of the Central Caribbean. Rotunno and Emanuel (1987) found that hurricanes that form from large initial tropical disturbances like Sandy did tend to end up large in size.


Figure 2. The initial disturbance that spawned Sandy, seen here on October 20, 2012, was quite large.

2) High relative humidity in Sandy's genesis region
The amount of moisture in the atmosphere may play an important role in how large a hurricane gets (Hill and Lackmann, 2009.) Sandy was spawned in the Caribbean in a region where the relative humidity was near 70%. This is the highest humidity we saw during 2012 during the formation of any Atlantic hurricane.

3) Passage over Cuba
Sandy struck Cuba as an intensifying Category 2 hurricane with 110 mph winds. While the core of the storm was over Cuba, it was cut off from the warm ocean waters surrounding Cuba. Most of Sandy's large circulation was still over the ocean, though, and the energy the storm was able to extract from the ocean went into intensifying the spiral bands over water. When Sandy's core re-emerged over water, the hurricane now had spiral bands with heavier thunderstorm activity as a result of the extra energy pumped into the outer portion of the storm during the eye's passage over land. This extra energy in the outer portions of Sandy may have enabled it to expand in size later.

4) Interaction with a trough of low pressure over the Bahamas
As Sandy passed through the Bahamas on October 25, the storm encountered strong upper-level winds associated with a trough of low pressure to the west. These winds created high wind shear that helped weaken Sandy and destroy the eyewall. However, Sandy compensated by spreading out its tropical storm-force winds over a much wider area. Between 15 and 21 UTC on October 25, Sandy's area of tropical storm-force winds increased by more than a factor of two.

5) Leveraging of the Earth's spin
As storms move towards Earth's poles, they acquire more spin, since Earth's rotation works to put more vertical spin into the atmosphere the closer one gets to the pole. This extra spin helps storms grow larger, and we commonly see hurricanes grow in size as they move northwards.

6) Interaction with a trough of low pressure at landfall
As Sandy approached landfall in New Jersey, it encountered an extratropical low pressure system to its west. This extratropical storm began pumping cold air aloft into the hurricane, which converted Sandy into an extratropical low pressure system, or "Nor'easter". The nature of extratropical storms is to have a much larger area with strong winds than a hurricane does, since extratropical storms derive their energy from the atmosphere along a frontal boundary that is typically many hundreds of miles long. Thus, as Sandy made landfall, the hurricane's strongest winds spread out over a larger area, causing damage from Indiana to Nova Scotia.

Are we likely to see more such storms in the future?
Global warming theory (Emanuel, 2005) predicts that a 2°C (3.6°F) increase in ocean temperatures should cause an increase in the peak winds of the strongest hurricanes of about about 10%. Furthermore, warmer ocean temperatures are expected to cause hurricanes to dump 20% more rain in their cores by the year 2100, according to computer modeling studies (Knutson et al., 2010). However, there has been no published work describing how hurricane size may change with warmer oceans in a future climate. We've seen an unusual number of Atlantic hurricanes with large size in recent years, but we currently have no theoretical or computer modeling simulations that can explain why this is so, or if we might see more storms like this in the future. However, we've seen significant and unprecedented changes to our atmosphere in recent decades, due to our emissions of heat-trapping gases like carbon dioxide. The laws of physics demand that the atmosphere must respond. Atmospheric circulation patterns that control extreme weather events must change, and we should expect extreme storms to change in character, frequency, and intensity as a result--and not always in the ways our computer models may predict. We have pushed our climate system to a fundamentally new, higher-energy state where more heat and moisture is available to power stronger storms, and we should be concerned about the possibility that Hurricane Sandy's freak size and power were partially due to human-caused climate change.

References
Emanuel, K. (2005). Increasing destructiveness of tropical cyclones over the past 30 years. Nature, 436(7051), 686-688.

Hill, Kevin A., and Gary M. Lackmann (2009), "Influence of environmental humidity on tropical cyclone size," Monthly Weather Review 137.10 (2009): 3294-3315.

Knutson, T. R., McBride, J. L., Chan, J., Emanuel, K., Holland, G., Landsea, C., ... & Sugi, M. (2010). Tropical cyclones and climate change. Nature Geoscience, 3(3), 157-163.

Rotunno, R., & Emanuel, K. A. (1987). An air–sea interaction theory for tropical cyclones. Part II: Evolutionary study using a nonhydrostatic axisymmetric numerical model. J. Atmos. Sci, 44(3), 542-561.

The Atlantic is quiet, but a Nor'easter expected next week
The Atlantic is quiet, with no threat areas to discuss. An area of low pressure is predicted to develop just north of Bermuda on Wednesday, and the GFS model predicts that this low could become a subtropical cyclone as moves north-northeastwards out to sea late in the week.

The long-range models are in increasing agreement that a Nor'easter will develop near the North Carolina coast on Sunday, then move north to northeastwards early next week. High winds, heavy rain, and coastal flooding could affect the mid-Atlantic coast and New England coasts next Monday and Tuesday due to this storm, but it appears likely that the Nor'easter will stay farther out to sea than the last Nor'easter and have less of an impact on the region devastated by Sandy. Ocean temperatures off the coast of North Carolina were cooled by about 4°F (2.2°C) due to the churning action of Hurricane Sandy's winds, but are still warm enough at 22 - 24°C to potentially allow the Nor'easter to acquire some subtropical characteristics. I doubt the storm would be able to become a named subtropical storm, but it could have an unusual amount of heavy rain if it does become partially tropical. The Nor'easter is still a long ways in the future, and there is still a lot of uncertainty on where the storm might go.

Jeff Masters

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My link didn't work- try anotherLink
Member Since: December 17, 2009 Posts: 0 Comments: 1230
410. yoboi
Quoting RussianWinter:


You know, there are many rocks out there!

You, out of all people, should know that life has been driven to near extinction once on this planet before...


...But hey, we survived!

Go team life!


i know like noah and the ark....
Member Since: August 25, 2010 Posts: 7 Comments: 2337
Quoting yoboi:


"big burning ball of gas" is that gas your talking about fossil fuels??? does shell, exxon etc own that burning ball of gas??? so in your words the bible is a hoax??


The day someone claims legitimate ownership of the sun... Is probably the day we'd be in trouble...

I wouldn't say it can't happen though ;).
Member Since: Posts: Comments:
Quoting yoboi:


so life could reform again??? good point...


You know, there are many rocks out there!

You, out of all people, should know that life has been driven to near extinction once on this planet before...


...But hey, we survived!

Go team life!
Member Since: Posts: Comments:
Quoting yoboi:


i answered your question without a question is it a hoax??

Parts of it are, yes. But how does that relate to global warming?
Member Since: Posts: Comments:
406. yoboi
Quoting goosegirl1:



As I said, I haven't worked around snow geese, only seen them on occasion. Does this help? Link


thanks for sharing the link...
Member Since: August 25, 2010 Posts: 7 Comments: 2337
405. yoboi
Quoting AegirsGal:
Not a who, a what. Physics. The dynamic combination of matter, gravity, and electromagnetism. Oh yeah, and that big burning ball of gas in the sky called a star. All observable, provable phenomenon.


"big burning ball of gas" is that gas your talking about fossil fuels??? does shell, exxon etc own that burning ball of gas??? so in your words the bible is a hoax??
Member Since: August 25, 2010 Posts: 7 Comments: 2337
Quoting AegirsGal:
Not a who, a what. Physics. The dynamic combination of matter, gravity, and electromagnetism. Oh yeah, and that big burning ball of gas in the sky called a star. All observable, provable phenomenon.
got swallowed on the previous page.
Member Since: August 2, 2011 Posts: 0 Comments: 291
Quoting yoboi:


lol it was not a test i have no clue to the answer thought maybe you had some insight.....



As I said, I haven't worked around snow geese, only seen them on occasion. Does this help? Link
Member Since: December 17, 2009 Posts: 0 Comments: 1230
402. yoboi
Quoting RussianWinter:


The earth is a rock that is still hot. Besides holding life (and other things) it's not much different than other rocks.

One thing for sure, the earth won't end. Life will, but the atoms in the rock will be atoms used in formation of stars, dust... and more rocks!


so life could reform again??? good point...
Member Since: August 25, 2010 Posts: 7 Comments: 2337
Quoting yoboi:


i answered your question without a question is it a hoax??


That's a question.
Member Since: September 18, 2008 Posts: 0 Comments: 616
400. etxwx
California's Cap and Trade Auction Begins Wednesday

Via McClatchy News - 11.13.12

Excerpt: Despite fierce opposition from much of the business community, California's grand experiment in taming global warming begins in earnest Wednesday.
Carbon trading isn't new. Polluters in the European Union have been subject to a greenhouse gas market since 2005, and a similar program covers power plants in the northeastern United States and eastern Canada.
But until Wednesday, when carbon trading comes to California, it's never been tried on a large scale in America.

Read complete article here.
Member Since: Posts: Comments:
Quoting yoboi:


ok i will go with that; who created nature???
Not a who, a what. Physics. The dynamic combination of matter, gravity, and electromagnetism. Oh yeah, and that big burning ball of gas in the sky called a star. All observable, provable phenomenon.
Member Since: August 2, 2011 Posts: 0 Comments: 291
398. yoboi
Quoting TropicalAnalystwx13:

Have you looked recently?



It's evolving just like the GFS said it was. If this is going to become a subtropical storm, look for it to just north of the island.


i answered your question without a question is it a hoax??
Member Since: August 25, 2010 Posts: 7 Comments: 2337
Quoting yoboi:


is there only certain books that we can use to determine how the earth was formed and will end???? if so please share the list we go by...


The earth is a rock that is still hot. Besides holding life (and other things) it's not much different than other rocks.

One thing for sure, the earth won't end. Life will, but the atoms in the rock will be atoms used in formation of stars, dust... and more rocks!
Member Since: Posts: Comments:
Quoting TropicalAnalystwx13:

Have you looked recently?



It's evolving just like the GFS said it was. If this is going to become a subtropical storm, look for it to just north of the island.


I said that based on what Stacey Stewart didn't do at TWO by adding a circle and we know he is bullish many times.
Member Since: April 29, 2009 Posts: 75 Comments: 14267
395. yoboi
Quoting Neapolitan:
Which one?

Anyway, the CPC is still calling for a mostly above normal United States for the remainder of the month:

CPC

CPC



neap if we debate can we do it in a timely fashion??? no need to call cleo or looking up old talking points mono mono....
Member Since: August 25, 2010 Posts: 7 Comments: 2337
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393. yoboi
Quoting AegirsGal:
Nature is as old as time, needing no book, but rather observation and and intellect with which to glean its patterns.


ok i will go with that; who created nature???
Member Since: August 25, 2010 Posts: 7 Comments: 2337
Quoting TropicalAnalystwx13:
The NAO is currently positive but leveling out. It should begin to plummet within the next few days, yielding a significant nor'easter next week.




So something like this?


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391. yoboi
Quoting goosegirl1:




Was it a test? Did I pass?


lol it was not a test i have no clue to the answer thought maybe you had some insight.....
Member Since: August 25, 2010 Posts: 7 Comments: 2337
Quoting yoboi:


i was just asking because ya said ya knew about habitat




Was it a test? Did I pass?
Member Since: December 17, 2009 Posts: 0 Comments: 1230
Quoting Tropicsweatherpr:
TA13,it looks like NHC will not have a circle afterall as nothing is trying to develop near Bermuda at this time.

Have you looked recently?



It's evolving just like the GFS said it was. If this is going to become a subtropical storm, look for it to just north of the island.
Member Since: Posts: Comments:
Quoting yoboi:


neap i use a book that is over 2000 yrs old; do you use a book newer or older just wondering....
Nature is as old as time, needing no book, but rather observation and and intellect with which to glean its patterns.
Member Since: August 2, 2011 Posts: 0 Comments: 291
Quoting TomTaylor:
If those people are stupid enough to believe they'd be better off succeeding from the most powerful nation in the world, I'd be more than happy to see them leave. Our nation would certainly be better off without those ridiculously unintelligent people.

...keep in mind I'm not encouraging a succession, nor do I think it will occur. I'm just encouraging those individual idiots to leave my country.
Umm--"succeeding"? "succession"? I think you need to check your vocabulary. The relevant words are "seceding" and "secession."
Member Since: Posts: Comments:
TA13,it looks like NHC will not have a circle afterall as nothing is trying to develop near Bermuda at this time.
Member Since: April 29, 2009 Posts: 75 Comments: 14267
385. yoboi
Quoting wxchaser97:
How did religion get into the subject?

Anyway...
It is supposed to be warm in SE MI this weekend. Should be great weather for football this weekend. Also, I believe the system southwest of Bermuda should've had a circle by now.


is there only certain books that we can use to determine how the earth was formed and will end???? if so please share the list we go by...
Member Since: August 25, 2010 Posts: 7 Comments: 2337
384. yoboi
Quoting goosegirl1:



I'm not sure of the mechanics of this.... sounds baffling. But snow geese were in danger of overhunting and came under management around 1970. 40 years of protection have allowed them to recover and thrive, and thus they are in need of management again to keep numbers in check, by hunting and controlled harvest.


i was just asking because ya said ya knew about habitat
Member Since: August 25, 2010 Posts: 7 Comments: 2337
How did religion get into the subject?

Anyway...
It is supposed to be warm in SE MI this weekend. Should be great weather for football this weekend. Also, I believe the system southwest of Bermuda should've had a circle by now.
Member Since: Posts: Comments:
382. yoboi
Quoting VaStormGuy:


I believe is science and what can be proven beyond a reasonable doubt if you look at facts. And by looking at facts, climate change being accelerated by CO2 emissions is real, while the bible is a very good work of fiction. And that's my opinion, and everyone is entitled to their own, and shouldn't push it on others.



i am not pushing anything on anyone if you belive it's a hoax that's your opinion....that's what is still great about this country freedom of speach you belive in your book and i belive in mine....i am in no position to judge your views....
Member Since: August 25, 2010 Posts: 7 Comments: 2337
Quoting yoboi:


what is causing the snow goose over population??? if they eat out the tundra no more green grass too feed turns into water and more ice coverage is this a good thing?



I'm not sure of the mechanics of this.... sounds baffling. But snow geese were in danger of overhunting and came under management around 1970. 40 years of protection have allowed them to recover and thrive, and thus they are in need of management again to keep numbers in check, by hunting and controlled harvest.
Member Since: December 17, 2009 Posts: 0 Comments: 1230
Quoting yoboi:


not being funny at all just wonder if people think the book of revelations is a hoax...i belive in the bible....


I believe in science and what can be proven beyond a reasonable doubt if you look at facts. And by looking at facts, climate change being accelerated by CO2 emissions is real, while the bible is a very good work of fiction. And that's my opinion, and everyone is entitled to their own, and shouldn't push it on others.
Member Since: Posts: Comments:
378. yoboi
Quoting Neapolitan:
Which one?

Anyway, the CPC is still calling for a mostly above normal United States for the remainder of the month:

CPC

CPC


neap i use a book that is over 2000 yrs old; do you use a book newer or older just wondering....
Member Since: August 25, 2010 Posts: 7 Comments: 2337
Quoting yoboi:




how does it not?

I'd appreciate it if you didn't answer my question with a question?
Member Since: Posts: Comments:
376. etxwx

Workers knock snow off trees at a park in Hegang, Heilongjiang province, on Tuesday after snowstorms hit the city. FANG BAOSHU / FOR CHINA DAILY

Power and water supplies disrupted, traffic at a standstill after storm
2012-11-14
By ZHOU HUIYING in Harbin and WANG QIAN in Beijing (China Daily)
Excerpt: After squeezing through a door blocked by snow, 56-year-old Kang Chuanguo and his family have been working tirelessly to salvage what is left of their farm. Of the four 400-square-meter greenhouses providing the family's sole source of income, only one has survived unscathed from blizzards that have hit Northeast China. One collapsed, while minor damage was caused to the others. "This snowstorm has cost us at least 40,000 yuan ($6,400)," said Kang, of Qianjin village, Hegang, Heilongjiang province. Although snowstorms are common in the region in winter, Kang said: "I've rarely experienced the kind of blizzard we're seeing now."

The meteorological department in Heilongjiang reported snowfalls averaging 50 cm deep in Hegang on Tuesday morning, equaling record figures recorded in the past five decades.

The snow, which began falling on Sunday, disrupted power and water supplies, caused traffic chaos and severe damage to hundreds of greenhouses. Hegang city's civil affairs bureau said that by Monday the snowstorms had affected 6,450 people, destroyed 145 greenhouses and 173 houses, causing estimated economic losses of 12.3 million yuan.

Power and water supplies were restored in most parts of the province on Monday evening.

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The NAO is currently positive but leveling out. It should begin to plummet within the next few days, yielding a significant nor'easter next week.



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373. yoboi
Quoting TropicalAnalystwx13:

How does this relate to global warming?




how does it not?
Member Since: August 25, 2010 Posts: 7 Comments: 2337
Diaster reliIef Team flies out of Palm Beach International Airport to help Hurricane Sandy victims

Florida DMAT Assisting Hurricane Sandy Victims

WEST PALM BEACH, Fla. - Seven members of the FL5 Disaster Medical Relief Team flew out of Palm Beach International Airport Monday morning and headed to New York to help Hurricane Sandy victims.

The team consists of 39 people who have experience in the medical field including doctors, practitioners, mental health specialists, logistics etc.






(A wonderful friend of mine from the Florida Keys is a member of the DMAT team)
http://www.wptv.com//dpp/news/region_c_palm_beach _county/west_palm_beach/Diaster-Relief-Team-flies- out-of-Palm-Beach-International-Airport-to-help-Hu rricane-Sandy-victims
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371. yoboi
Quoting Neapolitan:
Which one?

Anyway, the CPC is still calling for a mostly above normal United States for the remainder of the month:

CPC

CPC



why do you always post the USA map????? try posting the global map.....
Member Since: August 25, 2010 Posts: 7 Comments: 2337
Quoting yoboi:


not being funny at all just wonder if people think the book of revelations is a hoax...i belive in the bible....

How does this relate to global warming?
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369. yoboi
Quoting VaStormGuy:


Is that a serious question, cause I think you're being funny?


not being funny at all just wonder if people think the book of revelations is a hoax...i belive in the bible....
Member Since: August 25, 2010 Posts: 7 Comments: 2337
Quoting Xulonn:

Yes I do, but I try to not display my doomer feelings here.


Relax. As I said... Adaptation is probably a far more realistic option. Despite the stupidity of the many...

I do not have doubts on the creative capacities of smart or motivated individuals.
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367. yoboi
Quoting Neapolitan:
Which one?



i am glad you hitt the f5 key and found the courage to consult with me....kudos
Member Since: August 25, 2010 Posts: 7 Comments: 2337
Quoting yoboi:



does GOD count????


Is that a serious question, cause I think you're being funny?
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Quoting yoboi:



does GOD count????
Which one?

Anyway, the CPC is still calling for a mostly above normal United States for the remainder of the month:

CPC

CPC
Member Since: Posts: Comments:
Quoting TomTaylor:
If those people are stupid enough to believe they'd be better off succeeding from the most powerful nation in the world, I'd be more than happy to see them leave. Our nation would certainly be better off without those ridiculously unintelligent people.

...keep in mind I'm not encouraging a succession, nor do I think it will occur. I'm just encouraging those individual idiots to leave my country.
please. Its secession not succession( to be successful)
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Quoting RussianWinter:
Do you have any idea what it takes to stop a MASSIVE amount of energy?

Yes I do, but I try to not display my doomer feelings here.
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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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