The City That Plans to be Flooded

By: Douglas Hill , 14:22 GMT le 02 décembre 2011

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A guest post by Douglas Hill, a consulting engineer and an adjunct lecturer at the School of Marine and Atmospheric Sciences at Stony Brook University in New York.

Hurricane Irene, remember? Irene, diminished to a mere tropical storm when it struck New York City, came and went, soon disappearing from the news. But think back to August 26 when Irene, a Category 3 hurricane with winds of more than 110 miles per hour, was approaching the North Carolina coast and headed directly for New York City. Mayor Michael R. Bloomberg called a news conference to order 370,000 people to evacuate their homes. Then he stepped aside, and MTA chairman Jay Walder stepped to the microphone and announced that public transportation--buses as well as trains--was being shut down.


Figure 1. GOES-East visible satellite image of Irene taken at 7:45 am EDT on Sunday, August 28, 2011. At the time, Irene was a tropical storm with 65 mph winds, making landfall on Long Island, New York. Image credit: NOAA Environmental Visualization laboratory.

Evacuation without transportation: a novel concept that the mayor described as "preparing for the worst and hoping for the best." Fortunately, hoping for the best worked.

Unfortunately, the City is still hoping for the best, and it is not preparing for the worst. The coastal storm plan of the Office of Emergency Management (OEM) includes strategies for storm tracking, public information, evacuation procedures, people with special needs, recovery, and restoration, but nothing to prevent flooding.

In other words, New York City is planning to be flooded--and according to the National Hurricane Center, it will be. Based on the historical record, hurricanes of Categories 1, 2 and 3 will strike the New York region on an average of every 17, 39 and 68 years, respectively. The City has been overdue for a Category 1 hurricane--Irene should have been no surprise--and we may expect hurricanes of Categories 2 and 3 within the next decade or two. In testimony to a U.S. Senate committee, Max Mayfield, the former director of the National Hurricane Center, said, "It is not a question of if a major hurricane will strike the New York area, but when" (his emphasis.)

The greatest potential for loss of life from a hurricane has historically been from the storm surge. If the eye of a Category 3 hurricane crossed the New Jersey shore, the surge could reach 24 feet--compared with 4.5 feet in Hurricane Irene's--flooding the World Trade Center site and Wall Street, with City Hall resting on a separate island south of the rest of Manhattan. The ripples from a crippled financial district in lower Manhattan would be felt worldwide. In a severe hurricane, the OEM has estimated that up to three million people would have to evacuate, if that can be imagined.



Figure 2. The height above ground that a mid-strength Category 2 hurricane with 100 mph winds would push a storm surge into New York City in a worst-case scenario. The image was generated using the primary computer model used by the National Hurricane Center (NHC) to forecast storm surge--the Sea, Lake, and Overland Surge from Hurricanes (SLOSH) model. The accuracy of the SLOSH model is advertised as plus or minus 20%. This "Maximum Water Depth" image shows the water depth at each grid cell of the SLOSH domain. Thus, if you are inland at an elevation of ten feet above mean sea level, and the combined storm surge and tide (the "storm tide") is fifteen feet at your location, the water depth image will show five feet of inundation. This Maximum of the "Maximum Envelope of Waters" (MOM) image was generated for high tide and is a composite of the maximum storm surge found for dozens of individual runs of different Category 2 storms with different tracks. Thus, no single storm will be able to cause the level of flooding depicted in this SLOSH storm surge image. Consult wunderground's Storm Surge Inundation Maps page for more storm surge images of the U.S. coast.

Other major ports have taken measures to prevent being flooded. After the 1938 hurricane, storm surge barriers were built in New England to protect New Bedford, Providence and Stamford. After a disastrous storm in the North Sea in 1953, the Thames Barrier was built to protect London, and the Delta Plan was started in the Netherlands which includes three such barriers, one protecting Rotterdam, Europe's busiest port. Following Hurricane Katrina, a long-disputed barrier was constructed at the entrance to Lake Pontchartrain along with several others, which are now considered to make New Orleans hurricane-proof to Category 3 storms. Barriers are being completed to protect St. Petersburg, Russia, and Venice, Italy.

The heart of New York City could be protected in the same way. Moveable barriers, closed only when the city is threatened with major coastal flooding, could be placed at the upper end of the East River, across the Narrows and at the mouth of the Arthur Kill. Possibly, the latter two could be replaced with a single, longer barrier extending from Sandy Hook to the Rockaway peninsula. Modeling studies have demonstrated that the barriers would work. Four major engineering firms have presented conceptual designs and cost estimates for barriers at these locations. The estimated costs for these individual barriers range from $1 billion to $4.6 billion, with the total of the two or three needed less than $10 billion, comparable to other major infrastructure projects planned or underway.


Figure 3. Proposed hurricane storm surge barrier for New York City near the Verrazano Narrows Bridge. Image credit: Arcadis, Inc.

But unlike the original, the 2010 revision of plaNYC, the City's principal planning document, makes no reference to storm surge barriers. The City's latest plans are seen in the March 2011 Vision 2020: NYC Comprehensive Waterfront Plan, which calls not for protecting the waterfront, but for climate "resilience," the ability to withstand and recover from the disaster. Unfortunately, this may be the best that can be done for those living in the coastal sections of the boroughs that face the Atlantic Ocean.

So the Great Evacuation of August 2011 is a test. In its postmortem on the storm on September 5, the New York Times concluded that "by almost any measure, the evacuation was a success," but it did not report on the principal measure. How many people were left behind? Unlike New Orleans after Katrina, we won't know by counting the bodies. Not this time, anyway.

Douglas Hill, EngScD, P.E., Stony Brook University

Other posts in this series
Storm surge barriers: the New England Experience
Hurricane Irene: New York City's close call

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Quoting Hurricanes101:


Didnt they say they would also name the system that came across Florida this year?

They even acknowledged it would be classified in post-season but they did not name it at the time due to continuity since the East Coast of Florida already had high wind warnings and such.





they where but not any more
Member Since: 21 mai 2006 Posts: 5091 Comments: 115435
Quoting WxGeekVA:


Can I be a forecaster that issues TWOs and gets slammed for not putting a red circle on 3 thunderstorms?

You can do your own Tropical Weather Outlooks, but you cannot have it formatted the same or have it looking the same.
Member Since: 6 juillet 2010 Posts: 113 Comments: 32689
Quoting yqt1001:
For next hurricane season I've been planning to create my own "Liberal Forecasting Center" to at as a sorta unofficial NHC that is more liberal.

Pretty much, it's a center that names any storm that meets [S]TC standards for even just one second, as those count too. I find that the NHC is too inconsistent with all the different forecasters, and that they stay on the conservative side (which makes sense since they are a government agency).


Can I be a forecaster that issues TWOs and gets slammed for not putting a red circle on 3 thunderstorms?
Member Since: 3 septembre 2011 Posts: 13 Comments: 3477
Posted: 3:45 p.m. Thursday, Dec. 1, 2011
Sea-Tac Airport records highest atmospheric pressure reading ever

SEA-TAC AIRPORT, Washington

The highest atmospheric pressure ever recorded at Sea-Tac Airport was recorded Wednesday night, KIRO 7 Chief Meteorologist Rebecca Stevenson reports.

At midnight, the barometer hit 1043.4 millibars, breaking the previous record of 1043.0 millibars, set on January 28, 1949.

The all-time highest atmospheric pressure recorded in Seattle, with records dating back to the late 19th century, was 1043.9 millibars, or 30.83 inches of Mercury. It was recorded in downtown Seattle on December 3, 1921.

Here are a few other pressure records, courtesy of the University of Washington Atmospheric Department:


1043.4 millibars, 30.81 inches of Mercury-December 1, 2011
1043.0 millibars, 30,80 inches of Mercury -January 28, 1949
1042.3 millibars, 30.78 inches of Mercury - January 16, 1957


Seattle sets all-time record high pressure reading
Dec 1, 2011 at 5:23 PM PST

Seattle sets all-time record high pressure reading

We've managed to set a record...for calm weather.
Early Thursday morning, Seattle recorded a sea level pressure of 1043.4 milibars, or 30.81" of mercury, breaking the old record for highest pressure ever recorded at Sea-Tac Airport at 1043.0 mb set Jan 28, 1949.
The highest pressure reading ever recorded in Seattle was 1043.9 milibars (30.83") at the Downtown Federal Building almost exactly 90 years ago, on Dec. 3, 1921.

Link
Member Since: Posts: Comments:
For next hurricane season I've been planning to create my own "Liberal Forecasting Center" to at as a sorta unofficial NHC that is more liberal.

Pretty much, it's a center that names any storm that meets [S]TC standards for even just one second, as those count too. I find that the NHC is too inconsistent with all the different forecasters, and that they stay on the conservative side (which makes sense since they are a government agency).
Member Since: 19 novembre 2010 Posts: 1 Comments: 1286
108. Skyepony (Mod)
Quoting hydrus:
This was a mean storm they had about 6 months ago...


LOL~ well I started off watching the recent wind storm. You know how youtube goes for me..my weather perusing there tonight ended with this serious warning for tornado chasers.
Member Since: 10 août 2005 Posts: 208 Comments: 39047
Quoting TropicalAnalystwx13:

No, in the end they determined it was "something else" and did not meet either requirements of a Tropical or Subtropical cyclone.


Which makes no sense. If you had to call it something, might I suggest calling it a Micro-Subtropical Storm?
Member Since: 3 septembre 2011 Posts: 13 Comments: 3477
Quoting Hurricanes101:


Didnt they say they would also name the system that came across Florida this year?

They even acknowledged it would be classified in post-season but they did not name it at the time due to continuity since the East Coast of Florida already had high wind warnings and such.


No, in the end they determined it was "something else" and did not meet either requirements of a Tropical or Subtropical cyclone.
Member Since: 6 juillet 2010 Posts: 113 Comments: 32689
Quoting TropicalAnalystwx13:
Breaking:

The Unnamed Tropical Storm Tropical Cyclone Report is out


Didnt they say they would also name the system that came across Florida this year?

They even acknowledged it would be classified in post-season but they did not name it at the time due to continuity since the East Coast of Florida already had high wind warnings and such.

Member Since: Posts: Comments:
Quoting Skyepony:
There is some crazy videos out of Calgary of this wind!
This was a mean storm they had about 6 months ago...
Member Since: 27 septembre 2007 Posts: 1 Comments: 22254
hmm...good convergence for the area of concern (6S, 95E)
Link to Lower Level Convergence from 21:00UTC
Member Since: 4 août 2011 Posts: 46 Comments: 4488
102. Skyepony (Mod)
There is some crazy videos out of Calgary of this wind!
Member Since: 10 août 2005 Posts: 208 Comments: 39047
Quoting SPLbeater:
and i do not want to speak to cleverbot, all it will do is ask me my name 30 times lol
cleverbot is not clever at all........it makes me vomit.
Member Since: 27 septembre 2007 Posts: 1 Comments: 22254
and i do not want to speak to cleverbot, all it will do is ask me my name 30 times lol
Member Since: 4 août 2011 Posts: 46 Comments: 4488
Quoting hydrus:
made you laugh...
I hope we're talking about the same period like in the end of a sentence.ROFLMfAO.
Member Since: Posts: Comments:
Quoting SPLbeater:
im bored
I,m Chris....Pleasure meeting you Bored. Ever been through a full blown hurricane?
Member Since: 27 septembre 2007 Posts: 1 Comments: 22254
Quoting washingtonian115:
Lol.
made you laugh...
Member Since: 27 septembre 2007 Posts: 1 Comments: 22254
im bored
Member Since: 4 août 2011 Posts: 46 Comments: 4488
Quoting hydrus:
Stop quoting my period dammitt..:)
Lol.
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Quoting hydrus:
Stop quoting my period dammitt..:)

Well you quoted her period....nevermind...
Member Since: 22 octobre 2011 Posts: 0 Comments: 2553
Quoting washingtonian115:
.
Stop quoting my period dammitt..:)
Member Since: 27 septembre 2007 Posts: 1 Comments: 22254
Quoting CaicosRetiredSailor:
Evening Pottery, if you are around... I am having way too much fun here in Jamaica!

Imagine so. I wanna be there!
Member Since: 22 octobre 2011 Posts: 0 Comments: 2553
Evening Pottery, if you are around... I am having way too much fun here in Jamaica!
Member Since: Posts: Comments:
Updated track for Tropical Storm Harvey:

Member Since: 6 juillet 2010 Posts: 113 Comments: 32689
Quoting hydrus:
.
.
Member Since: Posts: Comments:
Cleverbot hates me. :(

User: I hate my camera.

Cleverbot: Who do you like?

User: Why...

Cleverbot: Yes. You're really dumb.
Member Since: 22 octobre 2011 Posts: 0 Comments: 2553
.
Member Since: 27 septembre 2007 Posts: 1 Comments: 22254
Quoting SPLbeater:
how the heck does a bug land an incondesant lightbulb that is like 300 degrees? why doesnt its feet get burned?

You should ask an expert. Here:

User: How the heck does a bug land an incondesant lightbulb that is like 300 degrees? Why doesnt its feet get burned?
Cleverbot: Know that your aunt has had double walking pneumonia? We're friends.
Member Since: 8 novembre 2009 Posts: 4 Comments: 13725
Quoting pottery:
How many people were actually evacuated from NewYork during Irene?
Good evening Pott..Check out this link..Link
Member Since: 27 septembre 2007 Posts: 1 Comments: 22254
how the heck does a bug land an incondesant lightbulb that is like 300 degrees? why doesnt its feet get burned?
Member Since: 4 août 2011 Posts: 46 Comments: 4488
How many people were actually evacuated from NewYork during Irene?
Member Since: Posts: Comments:
Quoting allancalderini:
It was Lee or Maria what the unnamed tropical cyclone would have been named

It would have been named Lee, which would have made the actual Lee be Maria, and all other storm names would be pushed down the list.
Member Since: 6 juillet 2010 Posts: 113 Comments: 32689
Quoting allancalderini:
It was Lee or Maria what the unnamed tropical cyclone would have been named


most likely Lee, Lee was a TD when the Un-named TS was probably peak intensity, close to call
Member Since: 4 août 2011 Posts: 46 Comments: 4488
Quoting allancalderini:
It was Lee or Maria what the unnamed tropical cyclone would have been named

Katia was named on 8/30, and Lee on 9/2. The unnamed cyclone became a tropical storm on 9/1, so would have been Lee if classified at the time.
Member Since: 8 novembre 2009 Posts: 4 Comments: 13725
It was Lee or Maria what the unnamed tropical cyclone would have been named
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the 850mb vorticy with the area around 6S 95E looks less like an oval opposed to dis mornin
Member Since: 4 août 2011 Posts: 46 Comments: 4488
Quoting HuracanTaino:
Religion an ideology, but first of all control, power, upon the weaker..
religion and ideology are control brokers.. logic is behind it all... which is to say, truth is in the eye of the beholder.. crazy people raise a gun at cops and fight invisible demons with swords at public intersections... war is calculated.
Thanks for the TCR memo... should help with my TPS reports over the weekend :P
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Quoting hydrus:
And religion...They argue the subject right here.
Religion an ideology, but first of all control, power, upon the weaker..
Member Since: Posts: Comments:
Quoting hydrus:
And religion...They argue the subject right here.
Those in power use religion to control and manipulate the populace.. war is about money and power.... period.. read your history and not the readers digest condensed version..
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new convective bursts over the area of concern near 95E 6S, lets see how longs this burst will last with the high wind shear:
Member Since: 4 août 2011 Posts: 46 Comments: 4488
Quoting JupiterKen:


No...most wars are based upon ideology
And religion...They argue the subject right here.
Member Since: 27 septembre 2007 Posts: 1 Comments: 22254
Quoting TropicalAnalystwx13:

Some interesting statistics, especially the one in bold.

Yes, that one really stuck out. And I just added this one to the list:

--This year's Lee is tied with 2005's Maria for the earliest formation of tropical storm #13; and this year's Nate is tied with 2005's Ophelia for the earliest formation of tropical storm #15.
Member Since: 8 novembre 2009 Posts: 4 Comments: 13725
Quoting Xandra:
A different kind of Santa Ana winds!

What is described as not typical Santa Ana winds caused heavy damage in Southern California. Jim Cantore has looks at some of the destruction

For some reason I can't view videos from the weather channel.
Member Since: 22 octobre 2011 Posts: 0 Comments: 2553
Quoting WeatherNerdPR:
So the TCR is out...

yup
Member Since: 22 octobre 2011 Posts: 0 Comments: 2553
Quoting JNCali:
Hey Rookie.. wars are most often based on greed. Some one wants someone elses land or resources or whatever. China is making all its money off of the Western consumer and so long as that is the status quo they have no motivation to shoot the missles (they stole from us) at us. The media loves to get everyone all upset so we stay on their channel and listen to their commercials.. and they make money.. it's all a game...IMHO


No...most wars are based upon ideology
Member Since: 3 mai 2010 Posts: 0 Comments: 306
Quoting Neapolitan:
As TropicalAnalystwx13 mentioned below, the Tropical Cyclone Report (TCR) for September's unnamed tropical storm was released a short while ago.

--The cyclone officially became a tropical storm at 1200z on 9/1, meaning it would have taken the name "Lee" (which formed the next day) had it been classified;

--The unnamed storm's maximum wind speed was 40 knots;

--The storm's ACE was just 0.8475, but that's high enough for 17th place on the season, ahead of both Jose and Franklin.

--September 2 is now the first of just five days this year during which two or more tropical storms existed. (The others were 9/7 through 9/10, with Katia, Maria, and Nate.) (No days had four or more storms, as we saw in 2010.)

--15 (79%) of this season's tropical storms formed before the statistical "peak", September 10th; just four (21%) formed afterward.

--With the unnamed storm, four TCs became tropical storms in just five days (Jose, Katia, Unnamed, and Lee); six became tropical storms in only 10 days; and ten became tropical storms in just a single 26-day span.

And now you know.

Some interesting statistics, especially the one in bold.
Member Since: 6 juillet 2010 Posts: 113 Comments: 32689
Quoting VAbeachhurricanes:


the people in power are smarter than you think, unlike afganistan, Iraq, and Iran (apart from Tehran) china has so much more infrastructure to worry about losing in a war. There is also a reason loan sharks never commit murder, dead people dont pay. China has nothing to gain, but everything to lose by going to war with us.


I can easily agree with your assessment.

I always keep to the thought that wars are seldom based on logic. Should China decide they could build a better future for themselves with the U.S. out of the picture, they may decide to proceed in that direction.
Member Since: Posts: Comments:
As TropicalAnalystwx13 mentioned below, the Tropical Cyclone Report (TCR) for September's unnamed tropical storm was released a short while ago.

--The cyclone officially became a tropical storm at 1200z on 9/1, meaning it would have taken the name "Lee" (which formed the next day) had it been classified;

--The unnamed storm's maximum wind speed was 40 knots;

--The storm's ACE was just 0.8475, but that's high enough for 17th place on the season, ahead of both Jose and Franklin.

--September 2 was the first of just five days this year during which two or more tropical storms existed. (The others were 9/7 through 9/10, with Katia, Maria, and Nate.) (No days had four or more storms, as we saw in 2010.)

--15 (79%) of this season's tropical storms formed before the statistical "peak", September 10th; just four (21%) formed afterward.

--With the unnamed storm, four TCs became tropical storms in just five days (Jose, Katia, Unnamed, and Lee); six became tropical storms in only 10 days; and ten became tropical storms in just a single 26-day span. (13 formed during just August and September, beating out the 12 that formed during those two months in 2010 and 2004. The average since 1995 is 8.4.)

--This year's Lee is tied with 2005's Maria for the earliest formation of tropical storm #13; and this year's Nate is tied with 2005's Ophelia for the earliest formation of tropical storm #15.

And now you know.
Member Since: 8 novembre 2009 Posts: 4 Comments: 13725
"Operationally, advisories were not issued on this system due to the intermittent nature of
the convection and the somewhat frontal nature of the satellite presentation. On a couple of
occasions advisories were prepared, but withheld when the convection began to diminish."

So we were very close to getting Maria from this....
Member Since: 19 novembre 2010 Posts: 1 Comments: 1286
So the TCR is out...
Member Since: 7 juillet 2010 Posts: 0 Comments: 5725
Quoting TropicalAnalystwx13:
Breaking:

The Unnamed Tropical Storm Tropical Cyclone Report is out

Awesome. Going to have to read it.
Remember the cleverbot stuff yesterday?
Member Since: 22 octobre 2011 Posts: 0 Comments: 2553

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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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