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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.
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
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)
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?
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 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!
They aren't saying that they don't expect a storm as damaging, or as strong, to occur every 700 years. They are saying that they don't expect a storm to approach with this type of path, at this time of lunar cycle, at this time of day more than once in 700 years. That doesn't mean that we can't or won't get Nor'easter, blizzard, or hurricane with an equally high level of destruction- it's a different type of storm.
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.
Yeah, but to paraphrase Terry Pratchett, everyone knows that a 1 in 700 year chance occurs nine times out of ten.
Proverbs 21:19
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.
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.
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.