There is another important factor in the surge’s ultimate impact: coastal geography. "Storm surge is like real estate: location, location, location," Rhome says. In New York Harbor, the surrounding coastline acted as a funnel, channeling more and more of the incoming water into a narrower and narrower region. When a massive volume of water gets confined in that way, "it has no choice but to spill out and flood the surrounding land," Rhome notes. And, in places where the shore gently slopes out to sea, rather than precipitously drops off, an even larger storm surge results. New York City, with some 305 square miles of area, is particularly vulnerable to storm surge because of its more than 500 miles of coastline feature small bays, inlets and other potential funnels that can channel rising seawaters far inland.
The art of surge prediction
An important part of coping with such floodwaters is knowing how likely they are to hit, and how high they will be when they do come ashore. The National Hurricane Center's Storm Surge Unit bases its projections on the amount of water that will physically move atop land, called the "wet" line above sea level. Of course, predictions can never be perfect, Rhome (who is also a former hurricane specialist) notes of his unit, as the parameters that influence storm surge change hour to hour: precise location of landfall, strength of the winds, the angle of approach to the coast, how fast the storm is moving, how big it is, among others.
In fact, the NHC is one of the few such facilities in the world that offers multiple predictions of storm surge to help emergency planners cope. It starts with a computer model that takes into account data on the coast itself, including its contours, its depths, natural structures and man-made ones, and where the rivers enter and other factors. The computer then simulates storm surge based on input wind speeds, the speed of the storm itself and its total size, which are in turn based on the best projection of the NHC's human hurricane specialists. That single best guess is where most storm surge predictions end.
But even the best meteorologists with the best tools and the most experience cannot precisely predict any of those things, so the NHC runs the model multiple times with multiple variations of the storm inputs, such as wind speed or the total area of the storm. The level of a storm surge can change quickly with relatively small fluctuations in such factors. "It's very tricky," Rhome says. "Just a subtle change in the meteorology makes a huge difference."
For example, Hurricane Ivan in 2004 shifted its track, and its eye passed to the east of Mobile Bay rather than just to the west, where it had been expected based on forecasts. This directional change of less than 30 miles cut the actual storm surge by 10 feet, according to Rhome, pushing water out of the bay rather than into it. "Anyone who thinks they can predict landfall within 30 miles two to three days in advance doesn't know what they're doing," Rhome says.
Or take Sandy, which remained only the weakest level of hurricane, boasting sustained winds above 74 mph, despite having the lowest pressure ever recorded for any storm north of North Carolina—943 millibars just prior to landfall in New Jersey. Instead Superstorm Sandy's sheer size—with winds spread over a massive area of more than 1,000 square miles—generated the enormous surge of ocean waters. To appreciate the difference, think of a smaller storm as like running a finger through a bathtub—it won’t disturb much water—whereas a larger storm is like moving a whole arm through—you can make a significant swell.
Rights & Permissions
See what we're tweeting about
17 Comments
Add CommentThe best part of having wetlands, forest, dunes, and barrier islands as buffers is they become homes to wildlife and give urbanites an area where they can relax and enjoy wild places when the weather is good.
Reply | Report Abuse | Link to thisI expect that New Jersey's boardwalks will be rebuilt but there's no better time than this to build the buffers that will help people weather the coming storm of Climate Change. The wild areas of Louisiana are so impressive that a visit there is like going back in time.
Building, or rebuilding oyster reefs, will be a good thing as well in spite of the pollution which will prevent people from using the resource for food. New York City is going to need hard defenses but the coast has had barrier islands in the past. Homes should be prohibited but camping, day use areas and marshes would improve NYC life immensely. All options for a buffer zone need to be considered, although property rights will most likely be a sticking point it will not get better to engineer change than now.
it is really sad news, and my thoughts and prayer gose to to people of sandy,New Jersy and New York. It seems natural disaster occuring more frequently than ever. i think the flooding happened in Sandy, is caused by wind and plate shift. Hopefully they all recover from this disaster and return to their normal life.
Reply | Report Abuse | Link to this
Reply | Report Abuse | Link to thisThe time is not for 'going back to normal'. This new freak storm (storms of which I have often spoken about here) should be a wake up call. Warming is here, it is not geting better, the tipping point was the Artic thaw and the methane being outgassed from the shallow sea floors, which has already doubled sum GHG emissions.
The longer it takes for action to address the unavoidable changes that must be made, as amply described by conservationists, it will simply make things worse. We must Clean Our Act Up – but not for fear. We must clean up for logic, for good sense, because it's the right thing to do, because the post-oil transition would only have to be done at a later date anyhow inevitably, while if we shift now there are still some reserves, we may leave a bit for posterity, regardless of warming, as a safeguard.
An extensive public geothermal program across most of the western US, as proposed by the MIT, would be the single largest step in this shift. Even a conservative could see the beauty of ceasing to regularly pay vast sums to one’s sworn enemies, and reaching self-sufficiency in energy.
http://geothermal.inel.gov/publications/future_of_geothermal_energy.pdf
http://www1.eere.energy.gov/geothermal/pdfs/evaluation_egs_tech_2008.pdf
Wind + solar + sea (as a portfolio), and deep geothermal (very stable, great jobs), complemented by nuclear thorium (far more abundant than uranium, almost no proliferation issues, great for mini-plants the size of a house) and the myriad gizmos that are sure to be invented, while nuclear fusion is perfected… WILL do the job.
It gives deep understanding of Science behind Sandy's Hurricane.
Reply | Report Abuse | Link to thisDr.A.Jagadeesh Nellore(AP),India
E-mail: anmakonda.jagadeesh@gmail.com
julianpenrod's rants should be archived as reference material for the next article on the topic of paranoia.
Reply | Report Abuse | Link to thisSuch an all-powerful conspiracy let's you post the 'truth' here for all to see? Convenient, isn't it?
Somebody thought access to the Internet might be therapeutic...
Reply | Report Abuse | Link to thisMaybe...I seem to have been deleted, but that not as important as the fact that they deleted the penrod, too! Think of how valuable the penrod's lunatic commentary could be for psychologists! Think of the loss to science! ;)
Reply | Report Abuse | Link to thisThough dealing with climate change is essential in the long run, places like New York and new Jersey need to find quicker, more local solutions to protect themselves from big storms and storm surges (and also, potentially, tsunamis). It seems like all the barrier systems proposed, whether "natural" (barrier islands, dunes, wetlands, and forests) or "artificial" (sea walls, tidal barriers, etc.) are both expensive and disruptive. I wonder why no one has proposed what seems to me like a simpler solution. Require new building to be built on raised land (or possibly sturdy pilings) so it is above the threat level. Unlike New Orleans, New York and New Jersey have access to nearby rocky hills and mountains which could be quarried to be used for fill. I don't know how the expense would compare. But fill has some great advantages. It does not require maintenance, and it can be done piecemeal, building by building, without having much impact on surrounding areas. If all the low structures were raised above the threat level, there would be no need for dikes or sea walls. (Port facilities and underground facilities would still need to be protected or engineered to survive flooding.) In addition to using fill to raise new construction above the threat level, maybe some low lying areas should be converted to parks and natural areas, and closed to development. The cities could buy back the land. Now would be the ideal time to do this, rather than rebuilding.
Reply | Report Abuse | Link to thisAs well as tide and wave power as well as Ocean Thermal Energy Conversion (OTEC).OTEC uses the temperature difference between cooler deep and warmer shallow or surface ocean waters to run a heat engine and produce useful work, usually in the form of electricity.
Reply | Report Abuse | Link to thisStorms happen, our land use practices determine whether there is a disaster or not. Few remember Reagan's plan to buy back the sand dune and island areas of the northeast coast back in the 1980's. Had we done so this storm would have been more of a curiosity than a disaster.
Reply | Report Abuse | Link to this
Reply | Report Abuse | Link to thisI'm from Russia.
Unfortunately, members of the government in our countries cannot be called intellectuals.
But, Your country often suffers from hurricanes.
I suggested the method of dealing with hurricanes, which is to make cyclones free from atmospheric precipitation in the ocean and not to make flood in the mainland.
At the same time - cost-no, but it turns out a lot of compressed and very cheap hydrogen.
Your rulers did not even deign to delve into the project.
I wait for the relevance will increase and when You regularly nature will make the world a flood in one single country.
Then, if I am alive - помогу. vetto@nm.ru
Do expect that such storms would surge in frequency and magnitude. carbon-oxygen dances at very intricate manner. Solution is not very simple - make oil/gas through carbon signaling technology and pump it back within 'empty' reservoirs where it has been 'sucked' out. Adapting to climate changes is not an option, reversing it would be if appropriately done by occupying work force in the right sense. Natural resources are constantly released by every human being and animal. Just let bacs work for us via the origin. If Nature have had locked energy stored in carbon matter, it has its purpose to serve Earth as a whole unity of interfering particles/strings/waves. We should learn from it, but abusing it. Life is not about money, life is about life's secrets. Energy is the potential difference of chained entangled interfering states. "God does NOT play dices" A.E.
Reply | Report Abuse | Link to thisWhy does the Facebook/Twitter window obscure the article's text. Is there a way to remove it?
Reply | Report Abuse | Link to thisThe corrupt government should not allow people to build at less than 100ft above sea level.there is other uses for the land,such as agriculture and forrests.
Reply | Report Abuse | Link to thisI think that stan e m has a point but perhaps we can put a sharper point on it. Instead of "big government" interfering, simply allow private insurance companies to scale their homeowner and property insurance fees according to the individual risk involved in a given property (just like auto insurance) and eliminate national flood insurance. Thus, those who choose to own structures in high risk areas will have to pay more, perhaps much more in premiums and the rest of us will not have to supplement their losses to the degree that we do now. Those who wish to build in an exceptionally high risk area might be denied insurance completely. Thus, the market place will ultimately decide where people build and what the price of repeated washouts will be for all of us.
Reply | Report Abuse | Link to thisMy guess is that within a few storm cycles, when people find that they must pay the entire cost of replacement entirely out of their own pockets, a lot fewer structures will be built below, say, 30 vertical feet above mean high tide.
Since the insurance companies will jack up the rates on everyone if unregulated, it would be better to fix the underlying problem of global warming.
Reply | Report Abuse | Link to this100 ft would cover sea level rise and tsunami
Reply | Report Abuse | Link to this