I have been through a number of cyclones at least as large, & much stronger than Sandy, in our tropical east coast area. During much of this time my home was not much more than 30Cm above the spring high tide line.

I have often wondered, rather idly, why the US east coast has such high cyclone surges. I have assumed it is to do with their gently shelving continental shelf, & the topography of coastal districts, but never known.

We are lucky in that our lack of Gulf Stream heating of our non tropical waters saves us from these things in the latitudes that the US experiences them. Still even where we are prone to them we don't get such huge surges.

I have wondered if the Barrier reef helps protect us there.

So there it is folks, my ignorance laid bare, & my laziness too I guess, asking you to hand me the information I am too lazy to research. It was a photo of water gushing into an underground station, & & another of the depth of water in New York that triggered my interest, so I thought of all the expertise on here going to waste.

Good topic, Hasbeen.

Here's a little something to chew on:

http://en.wikipedia.org/wiki/Storm_surge

I presume much of the coast affected by Sandy is low-lying and gently sloping. I heard someone refer to some of the flooded area around New York as being "reclaimed"

Population, building and Infrastructure Density, the answer in a line.
Then Poirots truth about the location, add the circumstances, the clash of weather pattens.
If a tree falls in the forest, and no one is there, will it still make a noise?
We can be happy past storms did not kill thousands, who did not live in its path.

@ Poirot,

New York (Manhattan and surrounds) is the most heavily populated low-lying area in America. Central Park is built on swampland and much of the shore line of Manhattan, with its cycle ways, paths and parks, is ‘reclaimed’.

@ Hasbeen

I don’t really understand the title of this thread. Are you asking why a Category 1 Hurricane, usual in August but rare in late October, sent inland by a polar front from the northeast rather than being able to continue its normal northward journey offshore, as well as coinciding with a lunar full tide, should cause so much damage to the densely populated and low-lying northeast US coastline? If so, I would have thought the answer was obvious.

Apart from the seaside cities and towns that line the shore, from the Carolinas all the way to Boston, many of which are merely a metre or so above sea level, Manhattan, the Bronx, Queens and Staten Island are low lying areas surrounded by water, namely the Hudson and East rivers. When the storm surges caused by Sandy (regardless of its category or wind speed) flowed north up the Hudson and East rivers as well as south, the waters 'met in the middle' and swelled further. That water had to go somewhere – in this case across the land, much of which by now was below sea level due to the storm surges and the high tide. This water, driven by wind gusts of up to 85mph, wreaked havoc.

Sandy was not “downgraded” when it reached land, as some have claimed. It was instead categorized as a “post-tropical storm”, not because its intensity lessened, but because, under the influence of the freezing northeasterly pushing it inland, it was cold. The nature of Sandy has been commented on by many on-scene reporters and residents as being unusual because a) the wind gusted, rather than blew constantly, b) the weather was cold, with bands of sleet and ice accompanying rain, c) the sheer size (measuring up to 400 miles across).

Given that, it is easy to see why Sandy caused so much damage.

Excellent summary, scribbler.

Thanks for clarifying a few points in such a succinct manner.

The title is confusing, mainly i think someone was trying to get in before it was blamed on climate change.
Best to say ocean temperatures don't exist and nothing has changed.

There is another major, perhaps primary factor, not mentioned by
scribbler.
It was reported that the air pressure dropped, from memory, to 960mb.
This caused the ocean to rise pushed up by higher pressures elsewhere.
The comment I saw said it was the lowest ever recorded pressure.

Found this on surges by NOAA

http://www.nhc.noaa.gov/surge/

Three reasons;

a) The Patriarchy
b) The Misogynist Tony Abbott
c) The military Industrial complex

Thanks for the answers, however none have given any answer to the original question.

Why do much stronger cyclones, of similar or even larger size not produce similar storm surges in our waters?

I saw some reports of surges of 4 meters & more in some areas from Sandy, where none of our larger & stronger cyclones in a 20 year period in the Whitsundays, generated more than a few inches.

Bazz may have come close with a 960 central pressure reading. Going from memory, even much stronger cyclones I have experienced in Queensland have not got that low. I have a memory of considering 980+ as very low. Problem is it's a few years back. Of course it is the difference in pressure that generates the winds, not the pressure itself.

Poirot thanks for the reference, but nothing there to differentiate between US & Oz surge levels, for similar events.

Scribbler Sandy had wind speeds well below cyclone strength for over 12 hours before crossing the coast, with it's huge surge, what it was categorized as has more to do with the message authorities wished to convey.

What I am interested in is the reason for those destructive surges on the US east coast, front events which would generate little if any surge on the Queensland coast.

I wonder if it is a matter that like the oil add, "cyclones ain't cyclones" & I am comparing apples with oranges.

579 do try to grow up a bit.

http://www.nytimes.com/2012/10/29/science/earth/shallow-waters-and-unusual-path-may-worsen-surge.html?_r=0

Hasbeen,

The above may help to answer your query then. A combination of counterclockwise rotation, extensive shallow offshore waters around the New York area, the unusual path of the hurricane (trapping water against the shores of New Jersey and New York), and the direct head-on landfall, all created a perfect environment for mayhem.

Quote: " 'As it moves west, the hurricane is expected to make landfall in New Jersey, perpendicular to the coast. Such a head-on hit can produce worse surges than a glancing blow because more water can be driven into estuaries and harbors.
“The bottom line for New York and New Jersey and Long Island Sound is that they are going to have the worst of the surge and coastal inundation,' Mr. Uccellini said."

As said earlier, if you look at a map of the affected area, you will see a huge number of rivers, basins, bays, harbours and estuaries - most particularly around the NJ and NY areas. As Sandy headed inland, it literally pushed the water ahead and around it, causing massive swells and surges. At one point, a buoy in the Hudson Bay recorded a 32 ft wave, which is a record breaker. When so much water is slushing around in narrow areas, it has to go somewhere.

Not really sure what else we can say.

Hasbeen Wonders why this was a double wammy, of hot wild wind seas from the SW merging with with icy cold wind from Canada. The answer is simple. It was caused by a ridge of high pressure from Canada created by reduced sea ice in the arctic by the October 2012 sea ice melt over a fast area of water, that absorbs solar energy and puts more moisture that creates a new warming weather patterns over a huge area where 80 million americans Live.

With only 15 people dead in NY City is over the worst of their Problems . But with 200 billion worth of damage It's going to take years to fix that. NY has problems with underground electricity supply to many major buildings because most the tunnels which carry the electricity cables are flooded, as are the underground railway and some bridges. Fire destroyed many fine old wooden houses in Queens . In other places and on the Island and coast that felt the power of 30 feet high waves, all that is left of many homes is the stumps.
I
Over 3 states 200 mm of rainfall fell. A dam broke flooding three town and in virginia . West Virginia has still had blizzards at 6 this morning (31-10-2012) CNN showed electric power lines *toppled by wet snow falling on trees and then on then bringing down the power lines. it could take up to six weeks to reinstate them on minor roads.

Thank god that that OBAMA created a national emergency organization with 1500 staff who have been creating local networks of volunteers to deal with the this problem. CNN interviewed governors and city majors who are working him Obama and praising him because of his foresight in employing so many people devoted to this problem. In this disaster it has been good to see so many Americans want a bipartisan approach.

Even so Romney last week said the national emergency organization with 1500 staff was not necessary, as he was opposed more federal programs

Hasbeen,

FYI - found this, which may help too:

http://www.ga.gov.au/hazards/cyclone/cyclone-basics/what.html

Most notably, it says: "Storm surge, or coastal inundation by seawater, is a lesser known phenomenon but can be the most dangerous element of a cyclone."

And:
"Potentially the most dangerous hazard associated with tropical cyclones which make landfall is storm surge. Storm surge has been responsible for more deaths than any other feature of tropical cyclones. Storm surge is a raised dome of water about 60 to 80 kilometres across and typically about two to five metres higher than the normal tide level. It is caused by a combination of strong winds driving water onshore and the lower atmospheric pressure in a tropical cyclone. In the southern hemisphere the onshore winds occur to the left of the tropical cyclone's path. In Australia, this is the east side on the north west and north coasts and the south side on the east coast.

The largest surge usually extends between 30 and 60 kilometres from the crossing point of the tropical cyclone centre, or eye. Its influence also depends on the local topography of the seafloor and the angle at which the cyclone crosses the coast. If the surge occurs at the same time as a high astronomical tide the area inundated can be extensive, particularly along low-lying coastlines."

And on top of all that it occurred at high water springs !

Hasbeen,

I doubt this link will answer your fundamental question, however, it's related to the subject....obviously the north-east of the US is vulnerable to storm surge. Anyway, you may be interested in this analysis of paper published in Nature this year:

http://www.princeton.edu/main/news/archive/S32/98/37G63/

its a co-incidence..of 4 events..
key of which is the timming of it..[at the full moon..indicating a matriarchal warning sign..

the flood damage is the only really bad fruit
of a super high/full moon\..tide..mixing with a cyclical spiral arm of cyclonic surges..

the huge tide surge..at EGSACTLY..the right time..AND PLACE*

i discussed it before the event here
http://www.celestinevision.com/celestine/forum/viewtopic.php?t=3379

http://www.celestinevision.com/celestine/forum/viewtopic.php?t=3337&start=30

and pretty much over perceptions of it
but those ignoring the signs..dont say you wernt told

but to return to why
all i can offer is HOW*
storm surge/full moon..timming.

Hi Hasbeen I followed up your URL and found the following which argues that Hurricane Sandy is the shape of things to come as predicted by most scientists regarding climate change and it effect on the US and Canada.

"The researchers found that the frequency of massive storm surges would go up in proportion to an increase in more violent storms and a rise in sea level, the researchers reported. They noted that climate models predict that the sea level around New York City could rise by 1.5 to nearly 5 feet by the end of the 21st century.

Hi all.

The mayor of New York did some thing this morning to deal with traffic chaos that takes effect from tomorrow morning. Cars with be stopped from entering NY City unless it has at least three occupants. This should cope with todays on e two hour long at wait bus stops and the flooded underground railway with its flooded tunnels and their burnt out electricity systems . Provide all other with better support service

As a practical way to reduce the global warming that is underway, mandatory peak hour shared cars could solve road congestion problems in austrlaia by deferringmore more freeway and main road construction thus freeing up funds to renovate urban railways and speed up buses on the existing roads they use

US Republican strategists have discovered that there is no pool so shallow that several million people won't drown in it. The latest one is that FEMA emergency organization set up by Obama to deal and according to CNN FEMA has 2000 experienced peoplein 8 states helping people to deal with this catastrophy.

Remember when started promoting the idea that Barack Obama was not born in the US, that man-made climate change is an Eco-fascist-communist-anarchist conspiracy, or that the deficit results from the greed of the poor, they now appeal to the basest, stupidest impulses, and find that it does them no harm in the polls. Nown the tide is turning foagainst them

Don't take my word for it. Listen to what two former Republican ideologues, David Frum and Mike Lofgren, have been saying. Frum "warns that conservatives have built a whole alternative knowledge system, with its own facts its own history, its own laws of economics". The result is a "shift to ever more extreme, ever more fantasy-based ideology" which has "ominous real-world consequences for American society" and the world

I think its time both Americans and Australians got on their knees and asked forgiveness for their wickedness. Then again you won't read that in the press. The warmist religion will take the higher moral ground deceiving the gullible.

Investigate the US Military HAARP program.I wrote off theories of this being able to change weather but am now having second thoughts.

Most of these extreme weather patterns are happening in the USA.This one has happened just before the elections in the USA.

They are now on the verge of using printing technology to create a human kidney.What else is possible that is beyond our conception?

GAWD!

...but thanks, Arjay. I've been seriously contemplating an extended holiday from OLO - and I think you might have just helped me to make up my mind.

Cheers : )

Arjay, having been working with RF since I was 15 I have heard every
possible thing blamed on RF.
I have not grown two heads, have been burnt to a crisp, not developed
a multitude of cancers and I am in the very best of health.
I suggest you buy your self a radar set and stand in front of it all day.
It will be the most efficient heater for the next winter.

I must admit however I have never heard of elections being affected by RF.
Next you will tell me that mobile phone towers cause everything !

"...but am now having second thoughts." There was a first?

Please don't, Poirot... it's nearly the Christmas season - what will we do if there's no sanity clause?

Alan Parker.

Arjay you just don't get it do you. Half the problem with the NY super storm was it was reinforced with ice cold wet winds coming from through Canada via the North atlantic where the artic ice melt a month before previous month and creating the bigest open sea through which suns the rays penetrate and warm the sea water. There much more moister in the air as consequence which intensifies the cold weather from Canada. Thats why the the warm rain in NY disapeared further flooding 4 states with cold rain. A double whammy , the like of which had never happened before and will only get worse as the artic ice sheet gets smaller next summer and in future summers with climate change the double whammies are even more damaging on the east of the US. Thank god that Obama employed 2,000 people to look after the victims. As snows has brought so power lines down in the rural areas the threat hiperthermia will kill a lot of older people.

WmTrevor,

"....what will we do if there's no sanity clause?"

Well seeing as you put it like that, I can't resist : )

Poirot finds his sensibilities challenged occasionally around here - especially as many of his long-time allies appear to be disappearing into the cyber ether.

Perhaps he'll just waft around a bit and not take things too seriously.

: )

Or perhaps he might like to exercise those little grey matter.

Bazz,

Absolument!...that goes without saying : )

That's just so funny. You guys are comic geniuses!

Posted by runner, Thursday, 1 November 2012 9:35:52 AM

followed up by

Posted by Arjay, Friday, 2 November 2012 6:46:33 PM

Bravo!

How can you not stick around Poirot, you cant not be amused by that old one-two.

Houellie,

Actually I meant to include runner's post in my lament.

Besides....I find your posts highly entertaining (and WmTrevors, amongst a few others) - worth sticking around for.

: )

Alan Parker •OAM

The mayor of New York did some thing 5 day to deal with traffic chaos and oil shortages. Cars have been stopped from entering NY City unless it has at least three occupants. This helped cope with two hour long at wait bus stops and the flooded underground railway with its flooded tunnels and their burnt out electricity systems . Which has stopped so many petrol station from being able to sell the petrol in their storage tanks. God knows what it will end up costing.

That not the real issue. Half the problem with the NY super storm was it was reinforced with ice cold wet winds coming from through Canada via the North atlantic where the arctic ice melt a month before previous month and creating the biggest open sea through which suns the rays penetrate and warm the sea water. There much more moister in the air as consequence which intensifies the cold weather from Canada. Thats why the the warm rain in NY got cold and further flooding 7 states with cold rain. A double whammy , the like of which had never happened before and will only get worse as the arctic ice sheet gets smaller next summer and in future summers with climate change the double whammies are even more damaging on the east of the US. Thank god that Obama employed 2,000 people to look after the victims. As snows has brought so power lines down in the rural areas the threat hyperthermia will kill a lot of older people and that risk has not gone away

Long term urban and coastal planning need to encourage car sharing and more efficient public transport is a practical way to cope with disrupted oil supplies global warming that is underway, mandatory peak hour shared cars could solve road congestion problems in Austraiia by deferring more more freeway and main road construction thus freeing up funds to renovate urban railways and speed up buses on the existing roads they use.is needed in Australia.