Hurricane Sandy's huge size: freak of nature or climate change?
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
Reader Comments
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Little boxes on the hillside,
Little boxes made of ticky tacky,
Little boxes on the hillside,
Little boxes all the same...
(Look, I was _ordered_ to drink beer somewhere above in this thread, what?)
It would be interesting to see a study done summarizing the changing expectations of the degree of sea level rise. That is, it is the predictions that are the object of the study.
From my casual anecdotal point of view, it seems like the rate of change of worsening expectation is itself increasing.
I imagine that will make its exponential leap off the north end of the chart the day that the caps slide off into the sea, and all scientists shriek together in an odd form of harmony.
If extreme weather events seem to you to be on the rise, your powers of observation are accurate. Scientific American's latest eBook, Storm Warnings: Climate Change and Extreme Weather, gives readers the tools to better understand what is driving climate change, what might be in store in the coming decades and how we can begin to reverse the detrimental effects that human activity is having on Earth's climate systems.
----
For November, we turn our attention to our immediate environment. Hurricanes. Blizzards. Flooding. Drought. If extreme weather events like these seem to be on the rise, your powers of observation are accurate. The first three-quarters of 2012 brought the worst European winter in 25 years, massive flooding in Australia, Brazil and China, and a deepening drought in the U.S. affecting more than 50 percent of the country. And then came the superstorm Sandy late last month, inflicting billions of dollars of damage to the Northeast. The likelihood of such extreme weather events is increasingly being tied to anthropogenic -- or manmade, mostly through overproduction of carbon dioxide -- global warming. It's no longer an abstract idea; it's being experienced directly and locally, on nearly every level.
http://blogs.scientificamerican.com/at-scientific -american/2012/11/13/storm-warnings-climate-change -and-extreme-weather-sas-latest-e-book/
Individual storms then, now, and in the future will be created/steered/dissipated by weather patterns. This has not changed. Just like how at any given moment, sea level on the beach is largely a function of being in a trough or a crest of a wave.
Climate change impacts the frequency and intensity of these events, as averaged over decadal or longer timescales. It is trend on top of noise. With the beach example, it's the average sea level of many many waves. Your comments in an attempt to sound sarcastic and witty were actually not grounded in much actual scientific evidence or discussion.
I certainly agree with Neo, above (stupid people), and wonder if the presence of same is not more of a threat to the human race than rising seas. With the sea, well, you can get above the water line. But with stupid people, you can only wait for Saint Darwin to act, and gosh those saint guys are slow sometimes.
But stupid and worse, intentionally ignorant people are everywhere. There seems to be no escape!
3:37 PM GMT on November 13, 2012
+3
I have a huge question..im asking
with the fed govt 14 trillion dollars in the hole or more..WHERE is THIS
money going to come from?.............Governor Cuomo To Seek $30
Billion In Federal Aid To Rebuild New York After Superstorm Sandy
RE: Ya know dose guys up the street that make & use phoney 5s 10 20s till their caught, well same thing except the Treasury tells official don't CATCH these. aka catch22B. Were there is a will there is a Bill or vice versa. -vis0
Scientists know all about harmony, but I'm not so sure we can actually manage it.
More beer, maybe. For the audience, at least.
In seriousness, yeah, I never thought I'd see scientists putting out this level of collective shriek in my lifetime, as somebody who grew up in a family of them. That's noteworthy in itself, folks. It really is. Scientists -- scientists don't really shriek, on any reasonably large scale. We live by the caveat and the tempered statement.
--->EEEEEEEEEEEEEKKK!<---
I leave you all. G'night.
;)
(The lurkers never _actually_ leave. But we do need our beauty rests, from time to time.)
errm... no. The California coastline consists nearly entirely of steep cliffs or rapidly rising hills with beaches at some of their bases.
The direct effect on the City of LosAngeles would be almost unnoticeable.
The County of LosAngeles would lose major portions of SanPedro-thru-LongBeach along with MarinaDelRey and smaller portions of other beach communities, but that's still far less than 5% of the county's land area.
HOWEVER, significant portions of inland California would become part of the Pacific. The capitol and its suburbs would become segmented into islets within a (new) Sacramento(thruStockton)Bay, and a greatly expanded SaltonSea would occupy a healthy-sized chunk of southeasternCalifornia.
You know, opinions and orifices and all that.
I actually consider the shifts in these conversations on this blog to be a great thing and a good sign for us all.)
I wonder if Nea would ever put his many many words into action in his local/county area. Actions speak louder than words, right.
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
105 PM EST WED NOV 14 2012
...COASTAL STORM SANDY SETS SOME NEW RECORDS IN OUR AREA...
ON OCTOBER 29, 2012, COASTAL STORM SANDY SLAMMED INTO THE NEW JERSEY
COAST. A LARGE AND DAMAGING WIND FIELD ACCOMPANIED THIS STORM. A
PEAK WIND GUST TO 68 MPH WAS MEASURED AT THE PHILADELPHIA
INTERNATIONAL AIRPORT. ACCORDING TO LOCAL RECORDS, THIS GUST IS THE
SEVENTH HIGHEST WIND GUST RECORDED AT THE AIRPORT. BELOW IS A
LISTING, BY RANK, OF THE HISTORIC PEAK WIND GUSTS FOR PHILADELPHIA.
RANK PEAK WIND GUST /MPH/ AND DATE
---- -----------------------------
1 94 MPH ON OCTOBER 15, 1954 /HURRICANE HAZEL/
2 88 MPH ON JULY 14, 1931
3 75 MPH ON JUNE 24, 2010 /THUNDERSTORM/
4 71 MPH ON JUNE 1, 1998
5 /TIE/ 69 MPH ON MAY 28, 2005 /THUNDERSTORM/
69 MPH ON MARCH 18, 1989 /THUNDERSTORM/
*7 68 MPH ON OCTOBER 29, 2012 /COASTAL STORM SANDY/
8 67 MPH ON MAY 8, 1984 /THUNDERSTORM/
...RECORD LOW PRESSURE SET AT PHILADELPHIA DURING COASTAL STORM
SANDY...
AT THE PHILADELPHIA INTERNATIONAL AIRPORT, THE PRESSURE DROPPED TO
953 MB AT 932 PM ON OCTOBER 29, 2012. THIS BROKE THE PREVIOUS RECORD
OF 962 MB, WHICH WAS SET DURING THE SUPERSTORM OF MARCH 13, 1993.
...RECORD SETTING STORM TIDE AT THE SANDY HOOK, NJ NOS TIDE SITE
DURING COASTAL STORM SANDY...
PRELIMINARY DATA PRIOR TO POWER BEING LOST, THE SANDY HOOK TIDE GAUGE
RECORDED A LEVEL OF 13.3 FEET MEAN LOWER LOW WATER /MLLW/, WHICH IS
AT LEAST 3.2 FEET HIGHER THAN THE PREVIOUS RECORD OF 10.1 FEET SET
DURING HURRICANE DONNA ON SEPTEMBER 12, 1960. FUTURE REVIEW OF THIS
DATA, ONCE IT BECOMES AVAILABLE, WILL PROBABLY REVEAL AN EVEN HIGHER
TIDE DURING MONDAY EVENING OCTOBER 29, 2012.
...RECORD SETTING WAVE HEIGHTS AT BUOY 44065 AND BUOY 44025 THE
EVENING OF OCTOBER 29, 2012 DURING COASTAL STORM SANDY...
WHILE THE OFFICIAL PERIOD OF RECORD IS VERY SHORT FOR BUOY 44065,
DATING BACK TO 2008, THE WAVE HEIGHT OF 32.5 FEET REPORTED AT 850 PM
EDT MONDAY EVENING OCTOBER 29, 2012 AT THIS BUOY, EXCEEDED THE
PREVIOUS RECORD OF 26 FEET SET AT ABOUT 9 AM AUGUST 28, 2011,
ASSOCIATED WITH IRENE. BUOY 44065 IS LOCATED NEAR THE ENTRANCE TO
NEW YORK HARBOR, 15 NAUTICAL MILES SOUTHEAST OF BREEZY POINT, NY.
AT BUOY 44025, THE RECORD 31 FOOT WAVE HEIGHT AT ABOUT 8 PM EDT
MONDAY EVENING OCTOBER 29, 2012, EXCEEDED THE PREVIOUS RECORD OF
30 FEET SET ON DECEMBER 11, 1992. THE PERIOD OF RECORD AT BUOY
44025 BEGAN IN 1975. BUOY 44025 IS LOCATED 30 NAUTICAL MILES SOUTH
OF ISLIP, NY.
BASED ON THE INFORMATION PROVIDED, IT IS SAFE TO SAY THAT BOTH
NATIONAL DATA BUOY LOCATIONS NEAREST SANDY HOOK, ACHIEVED A RECENT
RECORD EXTREME SEA STATE ON TOP OF AND PROBABLY VERY CLOSE TO THE
TIME OF THE RECORD STORM TIDE AT SANDY HOOK. ONE CAN INFER FROM THE
DATA THAT THESE WAVE HEIGHTS WERE THE LARGEST SINCE RECORD KEEPING
BEGAN IN THIS PORTION OF THE WESTERN ATLANTIC IN 1975.
$$
Everytime I'm reading such numbers I am wondering how much of that could be compensated by storing water in depressions like the Death Valley, the Dead Sea and the like. But I guess, aside of technical and other issues, that nobody ever calculated that.
And yet another thought: How many water nowadays is in the ocean instead of held back somewhere in the native woods? How many litres can hold a grown-up tree? How many cubic kilometres of water are in the Atlantic because in the 19th century in the U.S. many forests had been logged and still are logged in the tropics nowadays. I can't really imagine but it must be big, big numbers.
Don't forget the tides and waves on top of that.
None of the runs have shown that cold of air, but they do bring some arctic air down. Should get interesting in the next couple weeks.
It is fun to think about orders of magnitude. Here is a graphic showing how water is stored on earth. Biological water is over 1000 cubic kilometers, surely an enormous amount. Compared to my few liters of personal H2O that is indeed a big number, but compared to the total biological water is about .0001 % of the total which is pretty small in comparison, just a drop in the bucket (if that).
The Unknown
As we know,
There are known knowns.
There are things we know we know.
We also know
There are known unknowns.
That is to say
We know there are some things
We do not know.
But there are also unknown unknowns,
The ones we don't know
We don't know.
You know, it's the old glass box at the—
At the gas station,
Where you're using those little things
Trying to pick up the prize,
And you can't find it.
It's—
And it's all these arms are going down in there,
And so you keep dropping it
And picking it up again and moving it,
But—
Some of you are probably too young to remember those—
Those glass boxes,
But—
But they used to have them
At all the gas stations
When I was a kid.
GFS 1 week:
Euro 1 week, not quite as far out to sea as the GFS but much more so than its previous runs:
Assuming there's no surprise shift back this will provide a little redemption for the GFS which was beaten badly by the Euro on the previous Nor'easter, as well as Sandy of course.
Snow all the way to the Outer Banks of NC if that happened, lol.
"I still think the southern and eastern U.S. winter will end up warmer than some are forecasting. The PDO remains solidly negative, which has a more direct influence on the large scale wave pattern in the northern hemisphere than the ENSO does. Even if a weak El Nino holds on, the pattern is more likely to resemble La Nina across North America during the next 3 months. The current National Multi-model Ensemble forecast has progressively become more supportive of this idea since September."
That would be a change for them but I doubt the Outer Banks will be seeing snow this early.
Zachary Labe (Blizzard92) has an excellent winter weather blog if you're interested. It's primarily targeted towards the mid-Atlantic/NE however.
Where did I mention faith or ideology? I'm talking ways of knowing and understanding the human condition, communicating it and acting to change it. Mythology applies to all insight expressing the human quest that is not science - not just old stories from religion but all insight and non-scientific ways of knowing. In that I would include all arts, literature, music, film and some aspects of the social sciences, the healing arts, mathematics and theoretical physics. Lots more.
With that in mind, think for a minute who and what will have to change depending what goals are set for reducing the human contribution to climate change. Every single state, city, country and dwelling. Worldwide. And all humans living now and in the future. Societies will not change based on science. Societies are made of human beings who by and large don't understand or care to understand science. Other values take precedence, whether it be religion or just plain life experience. e.g. The hurricane evacs. Scientists made forecasts. People were asked to leave but they did not. Simple.
A bridge is needed - one that weaves science and human understanding. Scientists of all disciplines are capable of recognizing that but they're much better at creating new stuff than at communicating with non-scientists.
Apparently flooding in some neighborhoods in and around Laplace was comparable to Katrina. That being said, Isaac's areal damage was much more localized, and I'm still of the opinion that it doesn't merit retirement. Sandy is a different kettle of fish.
ETA: Though if you were talking about size, then yes, we can add Isaac to the growing list of unusually larger Atlantic tropical cyclones.
Read more here: http://www.charlotteobserver.com/2012/11/04/364402 7/nc-coast-a-hot-spot-of-rising.html#storylink=cpy
The link doesn't work, I'd like to read it, and send it a couple places, can ya help please sir?
Link
[citation needed]
Sure, lots of times, no doubt -and please, when it happens in something I have written, let me know. Mistakes detract, as well as distract, from an argument (a fact I spent a lot of years trying to get students to take to heart). And if we are having a contest about it, then context will tell. (That was a small, very small joke.)
I'm pretty sure you just fed a troll with this answer, because the answer is so obvious, and it was such a silly question ("I wanna be prepared" riiiight).
But whatever. Keep fightin' the good fight Neapolitan. :)
Have to commend this guy for his patience with the deniers. I would have been at wits end by now.
Thank you Mr. Northeyewallneveragain :)
I made you your own Wikipedia tag...
I come here to learn about meteorology, and tropical weather.
Pardon me for a weak moment in dealing with someone who refused believe that the bible doesn't represent observable, provable phenomenon.
Go ahead throw me under the bus.
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