Study: Don't blame hurricanes for most big storm surges in northeast

Pioneering Rutgers study examines atmospheric patterns during nor’easters and other extratropical cyclones

Hurricanes spawn most of the largest storm surges in the northeastern U.S., right? Wrong, according to a study by Rutgers University-New Brunswick scientists.

Extratropical cyclones , including nor’easters and other non-tropical storms, generate most of the large storm surges in the Northeast, according to the study in the Journal of Applied Meteorology and Climatology. They include a freak November 1950 storm and devastating nor’easters in March 1962 and December 1992.

A powerful nor’easter battered the US East Coast on Jan. 4, 2018. CREDIT NOAA

In a first, the Rutgers scientists found intriguing trends after searching for clusters of, or similarities among, storms, said study coauthor Professor Anthony J. Broccoli, chair of the Department of Environmental Sciences in the School of Environmental and Biological Sciences. It’s a new way of studying atmospheric circulation.

Understanding the climatology of storm surges driven by extratropical cyclones is important for evaluating future risks, especially as sea-level rise continues, the researchers said.

“The clusters are like rough police artist sketches of what surge-producing storms look like,” Broccoli said. “Like facial recognition software, clustering is trying to find storms that look like one another.”

“We wanted to understand the large-scale atmospheric circulation associated with storm surges,” said Arielle J. Catalano, the study’s lead author and a doctoral student in the Graduate Program in Atmospheric Science at Rutgers-New Brunswick. “It’s an atmospheric approach to the surge-producing storms.”

The study covered the 100 largest storm surges driven by extratropical cyclones at Sewells Point in Norfolk, Virginia, The Battery in southern Manhattan in New York City, and Boston, Massachusetts. It excluded hybrid systems, like Superstorm Sandy, that shifted from tropical to non-tropical or were tropical up to 18 hours before peak surges.

The Rutgers scientists examined tide gauge records from the early 20th century through 2010. They analyzed atmospheric circulation during storms to look for clusters, and studied climate variability patterns that influenced circulation in the Northeast. They also looked at the probability of surges linked to much larger-scale atmospheric patterns that cover vast areas.

They found that the biggest surges develop when slowly moving extratropical cyclones (low pressure systems) encounter a strong anticyclone, or high pressure system. That scenario leads to a tighter pressure gradient (the contrast between low and high pressure) and longer-lasting onshore winds, the study says.

This favorable environment for large storm surges is influenced by large-scale atmospheric patterns, including El Niño, the Arctic Oscillation, the North Atlantic Oscillation and the Pacific-North American pattern.

Though Superstorm Sandy in 2012 led to the largest storm surge on record at The Battery, extratropical cyclones spawned 88 of the 100 largest surges there.

The November 1950 “Great Appalachian Storm,” with wind gusts exceeding 140 mph in the mid-Atlantic region, generated the highest extratropical cyclone surge at The Battery: nearly 7.9 feet. That’s only 20 percent smaller than Sandy’s surge – 13 percent smaller if sea-level rise is not considered, the study says.

The water level during the 1950 storm was lower than during Sandy because the surge peaked at close to low tide. Future extratropical cyclones could cause Sandy-like flooding and coastal damages.

At Sewells Point, the highest surge was 5.4 feet in November 2009, while the highest surge at Boston was nearly 6.3 feet in February 2010. Of the 100 largest surges at those locations, extratropical cyclones were responsible for 71 at Sewells Point and 91 at Boston.

“The elephant in the room is sea-level rise,” Broccoli said. “That will likely matter more than how storms may change in the future, but what happens will be a combination of the two factors.”

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30 thoughts on “Study: Don't blame hurricanes for most big storm surges in northeast

  1. in all objectivity: Sandy was an extratropical cyclone when it hit New york. So Sandy was transitioned into a nor’easter.
    it just had the baroclinic forcing and intensicication while it was nearing landfall. it’s path was also just right for a high storm surge.
    as a rule of thumb: the more perpendicular a storm hits the coastline the higher the storm surge will be.
    there are exceptions though as forward speed does also count as a very important parameter of course.
    just to give an idea we had 2 gales this winter: one from the southwest that was the strongest and one from the northwest that was weaker. The strongest storm barely made a difference in tides but just because of the right angle the weaker one was the one that caused minor coastal flooding.
    the southwestern storm had gale force 11 for over 2 hours, the weaker one had just a 10 minute peak of gale force 10.
    in 1953 a “sandy -like” storm hit here (meaning big storm, right angle of impact, reasonably slow forward speed). also exactly at the spring tide peak. That’s why in the Netherlands they built the delta works.

    • Another issue with Sandy is that some of the most prominent damage was done in areas where it made no sense to build. Hoboken, NJ is on a flood plain. The dunes on the Jersey Shore that were wiped clean were unstable frontal dunes. At least in the Netherlands people know what they’re getting into, and, although I think it’s crazy to build at or near sea level it is an impressive piece of engineering.
      FYI: My brother-in-law is from Groningen, and I’m all-to-familiar with what a good NNW Wind will do along the coast in that area

  2. The elephant in the room is sea-level rise,” Broccoli said.
    Such metaphoric elephants are studiously ignored. Sea-level rise however is brought up incessantly.

    • It is a three millimeter tall elephant, and it has been again growing smaller the last couple of years. According to Gavin Schmidt, quadratic fit to the sea level rise underestimates the future development. It remains to be seen if a pubic hit I mean cubic fit works better or is the problem a maths problem at all. I’d assume engineering could solve what maths can’t.

    • Yes, they got the size order wrong. The storm surge is the elephant, but sea level rise is the flea on the back of the elephant. Which are you really more worried about?

    • The largest elephant in the at-risk area, 90-ton Lucy in Margate, NJ, https://en.wikipedia.org/wiki/Lucy_the_Elephant survived both the 1962 storm and 2012’s Sandy. It’s 65 feet tall, so at 3 mm per yer, sea levels will need 6,500 years to drown ol’ Lucy. By then the next ice age will probably move the east coast back out towards Bermuda.
      Meanwhile, Jumbo, a Lucy knock-off a few miles down the shore in South Cape May, NJ http://www.capemay.com/Editorial/february06/southcapemay.htm was demolished for non-performance in 1900. While Jumbo survived all meteorological comers, the town itself disappeared in the 1944 hurricane.
      As a kid in the 1950s I’d scavenge bricks and tea cups from the sand-filled ruins, and now South Cape May is a bird sanctuary (and a very nice beach).

  3. So once again. skeptics are correct: Sandy’s storm surge was terrible but not unprecedented or indicative of “climate change”.
    And since skeptics have also been proven correct about the non-crisis of slr, one wonders about the paper’s raising that as a bogeyman.
    Coastal issues like erosion and subsidence, as well infrastructure ageing and wearing out are actually relevant and honest. slr is neither.

  4. Off topic but interesting:
    Several days ago WUWT had a piece on scientists falsely claiming the Nobel Peace prize, in this case Dr Peter Stott of the Met Office. I sent a message via the Met Office’s feedback form. I received two very civil replies. The second, received today:
    “Good Afternoon Mr Wright,
    Thank you for your email and for taking the time to provide feedback concerning the content of Dr Peter Stott’s web page: https://www.metoffice.gov.uk/research/people/peter-stott
    I can confirm I have forwarded your information to the content owner for the page and requested an amendment. With regret I am unable to provide a timescale for this change but rest assured matters are in hand.
    Yours sincerely,………………”
    When I checked, I was very pleased that Dr Stott has amended the entry:
    “Contributed to the reports of the IPCC which was awarded the Nobel Peace Prize in 2007”
    This is a completely truthful statement and I would commend Dr Stott for quickly taking action.
    What a contrast with Michael Mann!
    Chris

    • Yes, all of their study sites are north of Cape Hatteras. Tropical cyclones north of the Cape are usually transitioning into hybrid or extratropical systems or are recurving out to sea. In addition, extratropical cyclones tend to be larger and more spread out. This means a greater fetch over a longer length of coast than compact tropical storms.

  5. It panders to the alarmists to continue to call tropical storm Sandy “Superstorm.” They made that term up from nothing, The name does not exist. It makes TS Sandy sound worse than a hurricane.
    We need to start calling things by their correct descriptors if we want to be accurate in our science and observations.

    • We should also note that TS Sandy ended up being a combination of two storms, a joining of Sandy and a very strong storm coming in from the northwest. So two strong storms hit the northeast U.S. at the same time on this occasion.

  6. “They analyzed atmospheric circulation during storms to look for clusters, and studied climate variability patterns that influenced circulation in the Northeast. They also looked at the probability of surges linked to much larger-scale atmospheric patterns that cover vast areas.
    They found that the biggest surges develop when slowly moving extratropical cyclones (low pressure systems) encounter a strong anticyclone, or high pressure system. That scenario leads to a tighter pressure gradient (the contrast between low and high pressure) and longer-lasting onshore winds, the study says.”
    How would you do all of the above analysis without using a computer model?
    Impossible. Another fake “science” report using computer simulations that are always wrong.

    • The boundary between the high pressure to the north(west) and low pressure to the south(east) is where the bang for the buck comes into play. The tighter the pressure gradient, the stronger the winds and strong winds with a long fetch gives you a big surge. It’s that simple. That’s been known for years and you don’t need computer models to tell you that.
      I would think (hope) they used the computers just to tabulate and compare the results of the exact meteorological conditions that brought about each storm’ surge.
      I spend part time on the western side of the southern Chesapeake Bay and it’s pretty easy to tell when the rollers are coming just by the wind speed and direction. A 25kt northeast wind over 35 nm of open water will give us teeth shattering waves in my sailboat plowing into them. A 25kt west wind gives me a rocket ride until I get about 8 miles out where the rollers start forming, then it becomes a surfing trip.
      Additionally wind direction and speed controls the amount of tide anomaly in our creek, which is very common there. Give us a nor’easter and a full moon and you need to be sure to loosen the dock lines.

      • rbabcock – February 15, 2018 at 8:22 am

        The boundary between the high pressure to the north(west) and low pressure to the south(east) is where the bang for the buck comes into play. The tighter the pressure gradient, the stronger the winds and strong winds with a long fetch gives you a big surge.

        I don’t think it matters which compass direction a “pressure” area is moving toward or attempting to move toward …….. if an opposing (opposite) “pressure” area is moving toward the former or is stalled in place blocking the path of the former, …….. then the boundary between those two opposing pressure areas is where you are gonna get “the big bang for your buck”.
        When those opposing “pressure” areas …… keep right on “trucking” across the landscape, there is seldom any great or devastating commotion at their boundary layer. Worse case, a few “thunder boomers” and a couple rain squalls.

      • SCG – I think we are talking about Nor’easters here which by definition is a deep low off the coast bumping into a high pressure to it’s Northwest. Low pressure to the north and High pressure to the south funnels air off the East Coast and you get no “bang for your buck”. As far as motion, a lot of the very devastating Nor’easters were basically cut-off lows the slowly eek their way up the coast, and the worst ones seem to occur in October when the water is still warm feeding the low.
        I’ve been flying airplanes and sailing for over 40 years and understand very much how all this effects the one spot you are in.

      • rbabcock, I live in north-central WV and I can attest to the fact we receive kinda violent weather noninfrequently. Normally, precipitation producing “low pressure” area tracks up along the Little Kanawha River channel from the West-Southwest and then on to the East-Northeast.
        But now, ever so often a “mean” low-pressure area tracks down along the Little Kanawha River channel from the East-Northeast and buts head with a high-pressure area that is overtop of us and all “ell” erupts with strong winds, lightening, thunder and heavy rain squalls. A typical “nor-easter”.
        But then, at other times, the “low pressure” remnant of a Gulf hurricane will come ashore and track Northward up the Mississippi River channel, producing copious amounts of rainfall along the way, …… and then Northeastward up the Ohio River channel into Pennsylvania. It will not directly “track” into West Virginia because the mountainous terrain prevents that from happening. Prevents it from happening EXCEPT, ….. except when there is a “high pressure” area located to the North or Northwest and tracking toward the East or Southeast.
        The aforesaid Eastward tracking “high pressure” ….. will force the aforesaid Northeastward tracking “low pressure” …… directly into West Virginia and then up over the mountains into Virginia (Maryland and Delaware) and producing copious amounts of rainfall along the way, resulting in minor to severe flooding.
        But major flooding and/or “flash flooding” will occur, especially in the Eastern and Southern mountains of WV, …… iffen when the above scenario occurs and there is a “blocking” or stationary “high pressure” area situate overtop Virginia and/or the East Coast. The aforesaid stalled “low pressure” will generate massive amounts of rainfall in the mountains of WV, ….. kinda equivalent to a large Holstein milk cow “peeing” on a flat rock. Most all of that rainfall will quickly flow off the steep mountains and down the stream and river channels ……. like someone “flushing” a commode.
        Cheers

  7. Sandy made landfall at the Battery at high tide AND with a full moon. I believe it was some kind of a super moon.
    “The elephant in the room is sea-level rise,” Broccoli said. Is he discussing the the so-called sea-level rise of the sea rising downward at the bottom?

  8. The USA has very poor sea flood defences compared with Europe. I live in south east England and Kent is 80% sea defence or sea cliff. Having seen the flood defences of New York and pictures of Galveston where there are hurricanes, it comes to no surprise that America gets flooded by the sea. Its time to spend and then floods will be a thing of the past.

    • @ philip middleton
      Philip M, ….. the total length of Great Britain’s shoreline is calculated to be 11,073 miles (17,820 km).
      The total tidal shoreline of just the US Atlantic Coast, from Maine to Florida, was calculated to be 28,673 statute miles. And that doesn’t include the US shoreline in the Gulf of Mexico which is 1,631 miles in length.
      And you think Americans should be building “floodwalls” to protect 30,000 mile of our coastline, ….. HUH?

      • But, but, but …… Eric Stevens, the building of flood walls and dykes also creates and/or exacerbates “flooding” problems.
        The upper Mississippi and Missouri River dykes are testimony to that fact.
        The constructing of dykes “narrow” the natural width of the “flood plain”, thus causing the flood waters to stall and/or “back-up” until they eventually overflow the dykes resulting in massive flooding.

  9. They found that the biggest surges develop when slowly moving extratropical cyclones (low pressure systems) encounter a strong anticyclone, or high pressure system. That scenario leads to a tighter pressure gradient (the contrast between low and high pressure) and longer-lasting onshore winds, the study says.

    I sure hope that’s not part of the Pioneering Rutgers study.

    They include a freak November 1950 storm and devastating nor’easters in March 1962 and December 1992.

    Don’t forget the Northeast Blizzard of 1978. My apologies for not having time to write up something for the 40th anniversary. I did attend an event sponsored by the Blue Hill Weather Observatory. This remains the definitive storm in living memory for people in Southern New England.
    I did write something for the 1962 storm which devastated Long Beach Island and destroyed my grandparent’s summer home, see
    https://wattsupwiththat.com/2012/03/06/50-years-ago-the-great-atlantic-storm-of-1962/
    https://wattsupwiththat.files.wordpress.com/2012/03/1962-mar-06-synoptic.jpg

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