Winter Coastal Storms – a Dangerous Mix of Hazards

The winter storm hitting us right now is a reminder of how coastal flooding and winter storms can mix and bring a dangerous combination of hazards.  While the winds in this storm are substantially weaker (good news) than the Blizzard of ’78, both storms hit during extreme spring tides. The 1978 storm was the worst flood event on record for places like Boston.

Winthrop Drive, in the Beachmont section of Revere, Mass., was flooded by waves and tidal surge during the Blizzard of '78 that overflowed the seawall (credit: The Boston Globe)

Winthrop Drive, in the Beachmont section of Revere, Mass., was flooded by waves
and tidal surge during the Blizzard of ’78 that overflowed the seawall and froze in the streets (credit: The Boston Globe)

The Blizzard of ’78 caused record flood levels and also multiple feet of snow.  Combined with freezing temperatures this led to a very dangerous disabling of coastal communities in the Gulf of Maine and Massachusetts Bay.

Rescue worker struggles to haul evacuation boat to the front door of this home in Revere, Mass (photograph by Paul Benoit, Boston Herald American).

Rescue worker struggles to haul evacuation boat to the front door of
this home in Revere, Mass (photograph by Paul Benoit, Boston Herald American).

The storm surge forecasts at New York City, Long Island Sound, and the New Jersey Shore for this evening’s storm are only calling for about 2 feet of storm surge, but it is coming on top of some of the year’s highest tides.  We do not provide forecasts for Boston, but our forecasts for The Battery and Kings Point, in the NYC region, suggest only a 1.5 foot and 2.0 foot surges, respectively.  NOAA’s two models predict a ~2.5 foot surge and ~3 foot surge at these same locations.


Stevens NYHOPS Storm Surge Warning System forecast for water levels at Kings Point (magenta), relative to mean lower low water (MLLW – normal daily low tide). Predicted tides are also shown (blue), as well as observed water levels (red) and two NOAA ET-Surge forecasts for comparison (green).

Above is the figure showing the astronomical tides, as well as several forecasts for water level, suggesting that moderate flooding (barely over seawalls in a few places) may occur in Long Island Sound.  Flood levels in the direst forecasts at the moment are more than 6 feet lower than those seen during Sandy for The Battery and ~3 feet lower at Kings Point, Long Island Sound.  Check for yourself as the storm proceeds, using the Storm Surge Warning System.

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Air Quality Measurements on Your Own Window Sill

[This is a guest blog post from Talmor Meir, a PhD student at Stevens Institute in the Maritime Security Laboratory.]


Good news to NYC and it’s neighbors: According to The New York Times air across our city is the cleanest it has been in at least 50 years.  The conclusions were based on the NYC Air Quality Survey, where measurements are taken at 150 locations throughout NYC metropolitan on a seasonal basis and applied regionally.  While I am in support of any effort done to improve the air we breathe, I think we, the citizens of NYC, can do better.  We can increase air quality awareness by improving our measurement resolution.  Let’s talk about air quality on a finer scale, in our own neighborhoods, on our own street, right outside our windows!

Air Quality-EGG is a project aiming to give citizens a way to participate in the conversation about air quality in their immediate environment. The egg resembles an ostrich egg that sits outside your window or inside your home. It has four sensors built in – Temperature, Humidity, Carbon Monoxide, and Nitrogen Dioxide. The Egg receives information from the sensors every minute and uploads it to a network cloud making all data accessible to the public. The idea is that if we implement such technology into our homes, schools and office spaces, we, the citizens and workers of New York, together, will be able to map the evolution of daily air quality across different neighborhoods.

Our atmospheric science and air pollution research group (Pullen, Meir, Orton, Blumberg) is trying to help encourage more citizens to join in this effort, to strengthen and broaden the network.  You can help us gain higher resolution across the NYC by implementing your own egg at home or work.  Air Quality Eggs can be ordered from for $185.  The setup is simple and I have found the support team for this project to be very responsive.  The egg is pre-assembled and you will be asked to create a profile for your egg, where you get to name it and include details such as location, what floor you live on, indoor/outdoor placement, etc.  Once you connect it to your internet router (just like you would any other computer in your home), it begins collecting data.  You can then see your specific egg and all other available active eggs across the world at:


Whether you purchase the Air Quality Egg or not, you can become part of the conversation by spreading the word and become active in chat forums and other media.  Visit this blog again soon to see some analysis of my Egg’s data, located down on Wall St, NYC, or simply follow my Egg’s measurements on your own using the map on their website.

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HUD Rebuild By Design: Plans for the Future Coast

I am honored to be part of a well-constructed, diverse-minded team for the HUD (federal Housing and Urban Development) post-Sandy “Rebuild By Design” competition, one of 10 successful teams of about 150 that applied.  The team was built and is guided by SCAPE Studios and Kate Orff, and includes designers, coastal engineers, the creators of ECO-ncrete, oceanographers, maritime high school educators, and a well-known expert on coastal fisheries, among other areas of expertise.  It brought a very wise mix of expertise and ideas on both physical and social resilience to the table.

The results of the “phase 2” set of coastal adaptation approaches are online, and four come from our team.  HUD-RBD organizers, including the Rockefeller Foundation, are seeking input on the entries, so please go and see what you think!

The entire page of entries, with a clickable map to locate one in your location, are linked here:

The entries from our team are:

Gardening The Bay: Jamaica Bay, NYC,

Living, Growing Breakwaters: Staten Island and the Inner Harbor,

More Wet Meadow, Less Land: Hackensack River, NJ (The Meadowlands),

Barnegat Bay Remade: Barnegat Bay, NJ,

You can actually leave comments and questions on the RBD website, with each entry.

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Hurricane Sandy Storm Surge Map Animations

Hurricane Sandy was a wild beast, with a powerful high pressure system, a hurricane, a nor’easter and a high tide all meeting simultaneously to cause the highest flood in NYC history.  As a result the peak flood height was poorly forecast by federal and academic scientists.  One of our main pursuits at Stevens Institute’s Davidson Laboratory (aka Center for Maritime Systems) has thus been “capturing Sandy” — creating a reproduction that is as accurate as possible.

Click to see an animation of Hurricane Sandy modeled wind and pressure driven storm surge (color shading) from Hatteras to Nova Scotia. Arrows are wind velocity vectors (see the scale arrow for a 33 m/s or 74 mph hurricane strength wind), contours are isobars - lines of constant atmospheric pressure. An inset panel shows the four day time-history of modeled surge near NYC's shoreline at Sandy Hook.

Click to see an animation of Hurricane Sandy modeled wind and pressure driven storm surge (color shading) from Hatteras to Nova Scotia. Arrows are wind velocity vectors (see the scale arrow for a 33 m/s or 74 mph hurricane strength wind), contours are isobars – lines of constant atmospheric pressure. An inset panel shows the four day time-history of modeled surge near NYC’s shoreline at Sandy Hook.

In order to do this, we needed to find the best representation available of Sandy’s winds and pressure, and accurately simulate Sandy’s storm surge using our ocean model.   We also then needed to compare the resulting flood heights around the region to verify that they are accurate (they are, to an average across several tide gauge stations of 15 cm rms error for the animation above, 16 cm rms error for the animation below).  

Above is an animation of Sandy’s winds, barometric pressure, and storm surge, which is just the wind- and pressure-driven water elevation.  Credits for our ocean modeling also go out to my colleagues Alan Blumberg and Nickitas Georgas.  It is based on the Stevens Northwest Atlantic Predictions (SNAP) model grid that we built last fall, as forced by atmospheric model forecast data from the NOAA National Center for Environmental Prediction Global Forecast System (GFS).  I also have made a 3-minute version with voice-over descriptions of what is occurring.

Note how the winds blew from the northeast across the coastal Atlantic Ocean during the three days leading up to Sandy’s landfall, and this started to pile water up against the mid-Atlantic coast.  This is due to Earth’s rotation (and the “Coriolis Effect”), which causes the net flux of water to move to the right of the wind direction.  As Sandy itself approached the New Jersey coast, higher atmospheric pressure (black lines) pushing down outside the circular center of the storm helped force water to rise under the center of the storm, where the pressure is lower. This is the “inverse barometer” effect.

Next up is an animation of Sandy’s winds, pressure and total water elevation, which is the storm surge plus the tides and plus anything else such as rainfall or river-driven freshwater flooding.  This surge modeling is on a nested smaller grid that receives inputs from the larger scale grid at its boundaries.  The smaller grid is the NYHOPS grid, used for our regular regional forecasts of storm surges and ocean conditions.  The simulation is based partly on GFS atmospheric forcing, but mainly on the best forecast we could find – a Rutgers WRF model forecast (by Greg Seroka and Louis Bowers).

Click to see an anmation of water elevation (color shading) in the New York City, New Jersey and Long Island region. Also shown are wind velocity vectors (arrow) and isobars.  The right panel shows a zoom to the NYC region.  The axes on the top right show water elevation at The Battery over four days.

Click to see an animation of water elevation (color shading) in the New York City, New Jersey and Long Island region. This simulation includes both storm surge plus tides.  (NOTE: Time is in GMT here, four hours later times than EDT. Fixing that …)  Also shown are wind velocity vectors (arrows) and white lines are isobars. The right panel shows a zoom to the NYC region. The axes on the top right show water elevation at The Battery over four days.  The methods used for this simulation are very similar to a recent peer-reviewed published paper.

Now that we have created simulations with good accuracy, we can show people a new perspective on what happened, and we can also do experiments on Sandy to better understand hurricane storm surges and better forecast them in the future.  Beyond that we can even use the storm surge modeling to test out adaptations that reduce or prevent flooding, as we’re doing for the federal HUD’s Rebuild by Design competition.

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Next Mayor: Continue to Lead on Climate

This is an Op-Ed published in the New York Times Room for Debate forum .  It was solicited by the RfD editor, with the topic being “transportation challenges for the next mayor”. It was eventually published under a somewhat different debate topic, without my permission or consultation (strange!):

How to make New York City More Livable

The next mayor of New York faces some tough challenges that go to the core of what keeps the city livable. Challenges that he or she will have to address include basic infrastructural issues like electricity, water, flooding, waste management, housing and development, to name a few. What should be the new mayor’s priorities?

Continue to Lead on Climate

The next mayor’s biggest challenge will be to expand upon Bloomberg’s efforts to reduce our climate footprint. After Sandy, flood adaptation will take center stage, and now we’ll have the will to tackle all the sensible, efficient defense measures we’ve been neglecting. Yet, protections against ever-rising seas are not enough, and they must be paired with aggressive efforts to stop the root of the problem – carbon emissions.

The New York City Panel on Climate Change (NPCC) projects our local sea level to rise by 7-31 inches by the 2050s, bringing regular monthly tidal flooding to some low-lying neighborhoods and making extreme floods like Sandy as much as five times more likely to occur. These sea level changes will be a challenge for NYC, yet they will be a humanitarian crisis for low-lying nations of the world such as Bangladesh, and other climate change effects like drought could lead to global food shortages.

It is crucial that we continue to take steps to limit our impact on our climate by reducing carbon emissions, even if these changes are often initially unpopular or difficult. In the transportation sector, examples already underway include the Second Avenue Subway, Select Bus Service, the bike share program, and increased use of energy efficient marine transportation, all of which should be continued or expanded in the next mayor’s tenure. Also, new strategies are needed to help fund improved public transit, such as the Schwartz Tolling Plan.

Lastly, the next mayor needs to continue to partner with other cities worldwide, particularly now that China has overtaken the United States in carbon emissions – Bloomberg is the chair of a coalition of 58 major global cities taking action as the Cities Climate Leadership Group. As has often been the case before, the steps we’re taking in NYC are having a much broader, global influence.

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Not a Priority: Federal Funding to Improve Flood Forecasting

Dear Dr. Orton:

Thank you for your submission of the proposal [(censored) title relating to improving our Storm Surge Warning System’s forecasting of storm surges] to the [(censored) federal program].

Although your proposal ranked in the top group and was very highly regarded by the review panel, we do not have the funds available this year to fund the project. Since we did not receive the increase from the President’s Budget request, we can only fund a couple of proposals from the [other environmental disaster] priority through [same federal program] [other sub-program] funds.

We are carrying over into fiscal year 2014 the top ranked proposals, including yours, with the expectation that we will fund your proposal in the late summer of 2014 pending the availability of funds. We are likely not going to know what the [federal program] budget is for 2014 until spring of 2014, and all funds are subject to Congressional appropriations. However, we do view this proposal and project to be a strong one that would benefit [federal program] and our federal partners. Thus, we will do our best to honor our commitment in 2014.

A panel of experts reviewed your proposal based on the criteria listed in the Federal Funding Opportunity. I will be sending to you a summary of the comments from the panel when I return to the office in a few weeks.

Thank you for your patience during what is a very busy time of year for us.


[program manger]


Was this a result of the sequester, or did they actually (as implied) plan a funding opportunity purely around the President’s budget request?

This proposal took a week of my time, and several days for several other scientists, all likely for naught. It is very difficult to find funding for academic flood forecasting, especially in the era of the sequester, when little or no judgement is utilized on what is worthy of funding.

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Sandy’s Staten Island Flooding Deaths: A Man-Made Disaster?

Ask people how fast the water came into New York Harbor with Hurricane Sandy, or how fast it rose, and you get a wide range of answers. Many people think it was like a tsunami that came in quickly, with dangerous currents. In some cases it was violent, particularly at the beaches where waves brought it on in abrupt fronts. However, in the harbor, the waves were small and the water rose at a maximum of only 2.1 feet per hour, with maximum currents in most places below 5 miles per hour. You would need a fair amount of patience to detect water rising at 2.1 feet per hour (about an inch every two minutes) if you were to stand and watch, and it is not a dangerous rise rate if there are areas of high ground or higher levels to your home or building.

So where did the most people die from Sandy’s floodwaters? New York Times published a map showing this information across the region. from which this zoom image is taken:

Map showing the south-east shore of Staten Island, fatalities (dots), and descriptions of cause-for-death.

Map showing the south-east shore of Staten Island, fatalities (dots), and descriptions of cause-for-death.

The Times map tool shows that the regions with the strongest spatial clustering of fatalities anywhere in Sandy’s path were (1) Staten Island’s southeast shore, shown above, and (2) Rockaway Beach.

I discussed this extensively with Matthew Schuerman, a reporter from WNYC, and his story is a very good and detailed study of one of the neighborhoods on Staten Island, complete with interviews, audio, and maps. The story I explained to him is one of topography, and I could never put it into as good words, so here is his text:

The square mile bounded by Midland Avenue, Father Capodanno Boulevard, Seaview Avenue and Hylan Boulevard turned out to be the most dangerous place to be in New York City the night of Sandy, in terms of deaths.

It also is a topographical “bowl”: the streets are several feet below Father Capodanno Boulevard, the thoroughfare that separates the neighborhood from the Atlantic Ocean.

Sandy brought with it an exceptionally high storm tide that reached almost 14 feet at Manhattan’s Battery. But it was a relatively slow-moving storm, and the water level rose gradually.

Phil Orton, a research scientist at Stevens Institute of Technology in Hoboken, analyzed U.S. Geological Survey data and found that even at the peak of the storm, the water at the edge of Staten Island rose by just about 2 feet an hour.

But that surge would not have reached the streets of Midland Beach until after the water exceeded the level of Father Capodanno Boulevard. Only when the water overtopped the boulevard, as it did at about 6:30 p.m. Oct. 29—the night of Sandy—would people notice it. And, while it is difficult to know exactly what led to any individual victim’s death, the rush of water appears to have caught people off guard.

“Then you have a whole ocean pouring into your neighborhood in minutes,” Orton said, “and it can be much more dangerous.”

If you are having trouble imagining what happened, take a heavy mixing bowl from your kitchen and put it in your bathtub. Fill up the bathtub while holding down the bowl, so it doesn’t float away. The water rises gradually outside the bowl, while the inside stays dry. But once the water level reaches the lip, it will come rushing into the bowl.

Once the water overtopped the shoreline berm, it filled in neighborhoods like Midland Beach with water very quickly, within tens of minutes, much like what happened in New Orleans and has since been labeled part natural disaster and part “man-made disaster”.

Looking back at how this dangerous topography could have come to exist, one has to look back to the 1950s. Due to susceptibility to flooding during moderate storms, likely two severe nor’easters that occurred in 1950 and 1953, the waterfront berm was raised in the 1950s to better protect the neighborhood from flooding. This protection was good enough to stop a moderate storm surge like Hurricane Irene’s, and that recent storm likely contributed to the sense of people in this neighborhood that they were adequately protected from the ocean’s waters.  Unfortunately, the insufficient level of protection also transformed Sandy’s flood rise from an inch every few minutes to 6-8 feet in a few tens of minutes, making it deadly.

Building permanent walls or berms successfully reduces risk for smaller flood events, leads to temporary safety, additional development in floodplains, and eventually, complacency. However, it also dramatically raises human risks when “surprise” large events go higher than the design height of the barriers (see New Orleans). Choosing a design height for barriers becomes especially problematic when sea level rise is accelerating, as we know they are now doing.

This relates to the recent term coined by Nassim Taleb, antifragile. Our great challenge is to create antifragile floodwater protections that bend but don’t break. Or put more directly, that help stop or reduce flooding, but when they fail they don’t make a more deadly hazard such as rapid-rising waters.

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