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Hurricane Sandy a 1-in-700-Year Event Says NASA Study
Rebecka writes "Hurricane Sandy, which pelted multiple states in Oct. and created billions of dollars in damage, was a freak occurrence and not an indication of future weather patterns, according to NASA's Goddard Institute for Space Studies via LiveScience. The study (abstract), which calculated a statistical analysis of the storm's trajectory and monitored climate changes' influences on hurricane tracks, claims that the tropical storm was merely a 1-in-700-year event. 'The particular shape of Sandy's trajectory is very peculiar, and that's very rare, on the order of once every 700 years,' said senior scientist at NASA and study co-author, Timothy Hall. According to Hall, the extreme flooding associated with the storm was also due to the storm's trajectory which was described as being 'near perpendicular.' The storm's unusual track was found to have been caused by a high tides associated with a full moon and high pressure that forced the storm to move off the coast of the Western North Atlantic."
... is that it is possible to flip a coin and have it land heads up 1,000 times consecutively - it can happen and is increasingly likely to happen in a larger number of trials. Same can be said for a "Sandy" occurring in consecutive (or near neighbor) years. One thing is evident - the east coast, sand bars, outer banks, etc, were formed and shaped by this type of storm. I expect the 700 year estimate is fanciful.
A feeling of having made the same mistake before: Deja Foobar
That's funny because the year BEFORE Sandy, we had a "Once in a Hundred Year Storm" hit the northeast. And then next year, the exact same thing happened again, but it was worse.
And this year, I expect the weatherman to say the exact same thing....
If telephones are outlawed, then only outlaws will have telephones.
Does that take into account that the weather has changed due to climate change (global warming) and these rare events will become more probable in this new climate?
... when another Sandy hits next year (or the next)? I think we are all seeing too many "one-in-x years" climate-related events (where "x" is 50, 100 or 700 years) lately!
we've been getting these once-in-a-lifetime storms every ten years or so nowadays
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
if you look at wikipedia, NYC gets hit by Category 3 storms once every 70 years on average. Sandy was barely a Cat 1 when it hit us.
the last one was in 1938. 135 mph winds when the storm made landfall at Long Island. we are actually overdue for a very powerful storm here
People who constantly blame everything on climate change - even events like hurricanes, where there is no scientific consensus on the matter - are as big a problem as the "I don't believe in global warming" crowd.
#DeleteChrome
Then we had some bad luck. Or God hates us. You pick.
You can't mitigate every single potential risk, you have to look at the odds of a given risk occurring and prioritize response based on that.
Those evil climate change deniers at NASA are up to their old tricks again!
Maybe you should visit the source, NASA's Goddard Institute for Space Studies http://www.giss.nasa.gov/ and see if you think this particular branch of NASA is soft pedaling global warming.
It's been James E. Hansen personal pulpit for the last 30 years.
Sig Battery depleted. Reverting to safe mode.
I have to commend GISS on this analysis. I would be to their advantage to say:
Climate Change Caused Hurricane Sandy!!!
But they took the data, and analyzed it and came to a scientifically sound conclusion that it was not purely a Climate Change caused event.
This is exactly how things should be done.
Also, the next time people get all up in arms saying:
This huge cold weather snap is proof against Climate Change!!
GISS can study that too and prove that no, the cold snap in one particular large region has nothing to do with Climate Change either.
Honest science kind of tends to fall in the middle on a lot of different issues. Our currently wild political hyperbole from both sides is where all these all encompassing gross generalizing and completely wrong statements come from.
On the other hand, natural disasters that make those who want to cut disaster relief look like hearless fools right before a presidental election are a 1-in-4 year event.
So, if we get another one like these in our lifetime, what then? NASA just says oops and people keep pretending like there isn't climate change happening?
One supposes that with new data the NASA scientists would revise their theories. If NASA's models are broken, then attack the models. Short of that, data-less speculation is just that.
My God, it's Full of Source!
OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
Well, the problem with that statement is that except for the "I do not believe in global warming" crowd, there's an awful lot of scientific consensus on the topic.
Lost at C:>. Found at C.
Agreed. One of the other posters pointed out that Sandy did as much damage as it did in part because of the effect of the moon and the tides. Now, I'm no climate scientist, but I was completely unaware that global warming was affecting the moon's gravitational pull.
700 years seems oddly specific. I wonder how that was worked out. It isn't like we have any real reliable date past say 100 years for example. How are they extrapolating 700 years statistically?
The entire US is overdue for a Category 3, not just New York.
A quick google search...
http://images.google.com/search?site=&tbm=isch&q=category+3+landfall+USA
http://4.bp.blogspot.com/-bJhUmJyxrQs/ULy7NL1QbAI/AAAAAAAACQw/RlSJLqrsz5Y/s1600/hurrdrou0613.jpg
looks promising.
Anyway. Pretty obv been awfully lucky recently.
-- perl -e'print pack"H*","6e656d6f406d38792e6f7267"'
These estimates are not based on counting the number of storms that actually occur, they are based on simulations of storm paths.
The probability that another one of these happens in our lifetime is about 10%.
The probability that another once-in-700-year event happens somewhere in the US even just next year is nearly 100%, since there are many more than 700 sites that keep and report these statistics. In different words, you expect multiple extreme weather events to be reported in the US every year.
Does that answer your question?
http://xkcd.com/605/
Lets not fall into the Gambler's fallacy, it don't mean that won't happen next year, and the next after it, or that should happen for sure in the next 700, 1000, or 10000 years. Also, odds of taking a certain, specific path are pretty low, as the odds of hitting a particular point of a dartboard, but that don't mean that no point of the dartboard will be hit, and the same for potential paths of destruction.
if it happens every 700 years then how can we blame global warming?
I think the key is if 1 in 700 year events start happening every second Tuesday, then I might be convinced.
I haven't thought of anything clever to put here, but then again most of you haven't either.
If NASA's models are broken, then attack the models. Short of that, data-less speculation is just that.
The (re)insurance industry has more or less admitted that its statistical models are broken and that "1 in X00 years" is a meaningless metric based on information that is no longer relevant.
The future trend is for the insurance industry to require mitigation for extreme weather events or you won't get (cheap or any) insurance.
https://www.google.com/search?q=it+is+rather+obvious+that,+for+many+regions,+hazard+risk+can+no+longer+be+seen+as+stationary
[Fuck Beta]
o0t!
Except the models claim that arctic zones should warm more than the equatorial zones, so that should reduce the amount of energy available to power storms.
i've lived in NYC on and off for over 30 years and this is my 3rd hurricane
gloria in 1986 or so
irene in 2011
sandy
lots of hurricanes hit NYC usually every few years. its quite normal
These records get broken as a matter of routine these days in exactly the way climate sciences has predicted for quite a while now: Things get more extreme and less stable is the main prediction. So while Sandy may have been once in 700 years for the past, it could well be 1 in 50 years or even worse in the future.
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.
I agree, people have already forgotten about Katrina it seems. And there are other models that imply that weather SHOULD be different as the earth moves from ice age to ice age. Sounds like a "keep calm" statement from the government so we don't lose sleep over what's to come.
"Sandy was barely a Cat 1 when it hit us."
True, if you look at it in a very simplistic fashion, i.e wind speed only. However, if you look at it in terms of size, Sandy was a MONSTER, and it hit in conjunction with another weather system of hard weather.
The total energy potential of Sandy, due to sheer size, was greater than quite a few Cat 3's etc.
As I recall Sandy was a tropical storm when it hit.
Found a pic of Sandy
http://en.es-static.us/upl/2012/10/Hurricane-Sandy-on-October-29-2012.jpg
Compared to...
https://upload.wikimedia.org/wikipedia/commons/thumb/8/81/Tropical_storm_irene_aug_27_2011_at_1059_est.jpg/932px-Tropical_storm_irene_aug_27_2011_at_1059_est.jpg
The size doesn't seem that dramatic.
So. Not sure what the monster part was. Apart from, ofc, the fact that it hit at an unusually high tide.
I believe most of the damage was storm surge, not due to land covered, or rain fall.
-- perl -e'print pack"H*","6e656d6f406d38792e6f7267"'
If I heat the polar regions (more than?) the tropics, how will this reduce the energy warming the tropics?
They feared that it could be used to suppress protest or support unpopular rule.
Erm. Right. Point of pic, really, was that as hurricanes fall apart into tropical storms, they are almost always huge things that cover like most of the east coast.
Compared to pics of hurricanes falling apart into a tropical storm as they track up the coast that I recall and could find of the past, Sandy seems pretty typical.
The dramatic part was the high tide and pushing that storm surge up against New York City which was woefully unprepared despite warnings in the past (shades of Katrina).
-- perl -e'print pack"H*","6e656d6f406d38792e6f7267"'
Anecdotally speaking, I think that meteorological records are being broken at an unprecedented historical level. Just what I've noticed, and I have been fooled by evidence in the past.
They feared that it could be used to suppress protest or support unpopular rule.
These estimates are not based on counting the number of storms that actually occur, they are based on simulations of storm paths.
The probability that another one of these happens in our lifetime is about 10%.
The probability that another once-in-700-year event happens somewhere in the US even just next year is nearly 100%, since there are many more than 700 sites that keep and report these statistics. In different words, you expect multiple extreme weather events to be reported in the US every year.
Does that answer your question?
Its not even separate sites. Its that "type of storm". One area can be hit with multiple "types" of storms that break the 1 in model. 2005 New Orleans was hit with Katrina a 1 in 400 year storm 2008 New Orleans was hit with Gustav 1 in 100 years 2012 New Orleans was hit with Isaac 1 in 100 years The events were different... Gustav was really strong, Katrina had the massive storm surge, Isaac sat over the city instead of moving on, etc... So the 1 in whatever is pointless.
Even less certain are changes in hurricane tracks due to climate. As the Arctic warms up, some scientists suggest the temperature difference between higher and lower latitudes will drop and weaken the jet stream, making storms less likely to follow this stream out into the Atlantic.
"First they came for the slanderers and i said nothing."
Yeah, but to paraphrase Terry Pratchett, everyone knows that a 1 in 700 year chance occurs nine times out of ten.
Proverbs 21:19
Storms are essentially heat engines, but they do not run on the differential between the poles and the equator, they run on the differential between the surface and the upper reaches of the troposphere.
Given that, I see no mechanism for polar warming to offset warming of the oceans in the tropical zone.
You are missing knowledge about what the phase of the moon is, and how it applies. Tides are more complicated than "follow the moon" because the ocean/sea floor has considerable impact. But the thing with tidal forces isn't that the size changes, but that the distance changes. That is, tidal force is the differential between two points and that is a function of distance. If its night and the moon is full it is closer to you than when its night and it is a new moon (e.g., already set and on the other side of the earth). This variation in proximity causes change in the tidal forces.
I haven't followed this, but the argument seems to be that all forces combined to bring water higher than normal, ergo the greater flooding.
How useful is this to know? It's not like New York is now definitely safe from hurricanes for the next 700 years.
systemd is Roko's Basilisk.
I thought the main thing about the phases of the moon was to do with the sun-earth-moon angle - higher tides when the moon and sun are opposed or in conjunction, lower tides when they're at 90 degrees to each other in the sky*.
*roughly
systemd is Roko's Basilisk.
Perhaps without so much polar differential, they can linger and pick up/drop more rain along the way. ;)
They feared that it could be used to suppress protest or support unpopular rule.
The NASA paper does not say that Sandy was not influenced by climate change. What they actually calculate is that Sandy-like hurricanes occur once in 700 years under pre-industrial conditions. Here is one of many relevant quotes:
Someone should have RTFA.
...as a claim that storms as damaging as Sandy occur in this area with only a 1-in-700-year probability. As the article says, however, this was an unusual storm in a number of ways, and a more conventional storm causing at least as much damage is more probable than a repeat of Sandy.
Seriously, look at those pics again... And compare the scale of the pictures themselves... Then you'll see that Sandy absolutely dwarfed Irene... Hint: In the Sandy pic, the scale is such that you see a sizeable portion of Florida.. The Irene pic, you have the Norfolk area as the southernmost part...
We have such an opportunity to expand our vocabulary - new words, like haboob, and dericho.
So I measured the two pics in google maps for an approximate estimate of what to my eyeball looked like two pretty big storms, only Irene with a more definite central eye.
From the bottom of Sandy to the top (where, admittedly there's clearly a bit of weak storm cropped, but Irene is clearly a lot wider and more of a spiral, so would win on width)
versus
From the bottom of Irene to the top of the pic.
Both were (very approximately) ~915 miles from top to bottom in those pics.
From the far left of the storm sweep of Sandy to the eye (which is out on its lonesome in the ocean), measured horizontally.
~740
The width of Irene in the shot is massive, and hard to work out due to the coastline being obscured, and similar to the case of Sandy, goes off frame to the right.
But I got, approximately:
~845
Soo. On those pics, again very approximately, ~900x~750 for Sandy and ~900x~850 for Irene. I think they are comparable.
I can tell you that in our part of Maryland, Sandy was mostly a dud. The derecho did more damage to the house and trees - the winds didn't really feel like much at all. I don't think we got any gusts that came close to tropical storm strength.
Not to minimise what happened to New York and New Jersey, just because Sandy clearly covers all of Maryland, to mention that it didn't really feel like much of a storm to us experiencing it in eastern Maryland. The power went out for maybe... 5 minutes. I checked the outtage map along the shore from BGE. There were a number of outtages, but again, not as bad as the derecho.
-- perl -e'print pack"H*","6e656d6f406d38792e6f7267"'
http://m8y.org/tmp/temp.jpeg
A rough approximation of shapes, as near as I can make out from landmarks.
Sandy is larger, but, doesn't seem to be that much larger to me.
And, as noted in comment to AC, my experience of Sandy in maryland was *very* different from that of people in NJ and NY (as in, barely felt like a tropical storm in the impact on our counties in terms of power loss and damage).
-- perl -e'print pack"H*","6e656d6f406d38792e6f7267"'
I guess I should say, didn't even feel like a...
Anyway. Sandy was definitely spread over a large area, which helped diffuse it further.
You can talk about total energy, but if the storm is spread over the entire continent, it isn't very interesting.
Most places make clear the storm surge was the worst damage, and that would certainly have been helped by having been spread out, while, the results inland would have been significantly less.
The need for storm surge protection for New York City had been known for years prior.
-- perl -e'print pack"H*","6e656d6f406d38792e6f7267"'
First, the research extrapolates to a 700 year period from data that at best can be considered to cover 150 years. Of that period we have well defined hurricane tracks for perhaps 80 years. And it's only with meteorological satellites in the past 40 or so years that we've seen hurricanes from birth to death. There are plenty of stochastic models that will give you whatever outcome you desire.
Hurricanes with Sandy's characteristics may have always been, for example, 1 in a century hurricanes due to dynamics that the stochastic model above completely fails to anticipate. But we had so little data that this is the first one we have seen with these characteristics.
Second, we are ignoring the consequences of observation bias. Given the many hurricanes that have happened, I bet we'll find that most have tracks that would be similarly infrequent. Consider the case of flipping a fair coin ten times. No matter what the outcome of heads and tails in sequence, it will be a 1 in 1,024 event. There are a fair number of hurricanes that hit the mid-Atlantic states. Each one may take an infrequent path. I see nothing unusual in hurricane Sandy being rare or for that matter not particularly rare.
I think we'll find that these 1 in 700 events never were 1 in 700 or perhaps that there are many hundreds of 1 in 700 hurricane events. I find this sort of research to be remarkably flawed logically and statistically.
In fact, the only use I can see for this research is to provide an easy talking point for extreme weather advocates. Sandy was a 1 in 700 year hurricane therefore extreme weather from "climate change" is real.
Forgot what about Katrina? New Orleans gets hit by hurricanes. It got hit by a hurricane. There's nothing to "forget".
I would like to point out that NASA considers a quantitative risk assessment to be a +/- order of magnitude tool. So if the actual frequency turns out to be within 70-7000 years, the QRA is as acceptable.
... really, _700 years_ of records? And the margin of error on those early 'records' would be? And the margins of error on your model's assumptions would be? Oh, and did all your models agree on this or were they in agreement +/- some margin?
Vague hand waving at best, attempt to placate/influence at worst.
What should have been said, "We _guess_ that _maybe_ it was a 1 in 700 hundred-ish year-ish event. But that could be totally wrong. Thanks for listening."
"Consensus" in science is _always_ a political construct.
I described how tidal forces work and how distance varies that. IIRC (I haven't read anything on the topic in years) the sun has greater tidal force than the moon, but traditionally people always say the moon and historically sailors have often viewed the moon as special.
With respect to moon/sun opposed or in conjuction that would be full moon and new moon respectively, with the 90 degree points the quarter moons. GP wondered why, if the moon's size (mass, I'm assuming was meant) that anything changed. Distance matters and with tidal forces it is particularly the differential acting on a body. A basic answer. Introducing the sun's influence serves to illustrate how it is even more complicated. But it is all part of the same thing.