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M8.7 earthquake in Western Pacific, tsunami warning issued

earthquake.usgs.gov

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Re: M8.7 earthquake in Western Pacific, tsunami warning issued

#161

Post by timr »

BalinKing wrote: post #143
timr wrote: post #125

Earlier quoted context omitted.

No. That's the predictions. Biggest wave so far has been 60cm (EDIT: as of 6am UTC it's 1m30cm, but that's still relatively small. It came up almost exactly to the top of the pier in Kuji.)

I've updated my comment, I indeed misunderstood what I read.... Unfortunately it's too late for me to delete the comment, so everyone please feel free to flag/downvote it (both to push it down for the sake of clutter, and also to punish my carelessness :-P).

No worries -- the way they present it is confusing, particularly if you're watching the NHK World stream, which layers poorly translated English versions on top of the Japanese.

Re: M8.7 earthquake in Western Pacific, tsunami warning issued

#162

Post by brazzy »

nessex wrote: post #158
TylerE wrote: post #79

Earlier quoted context omitted.

Despite the common vernacular calling them "waves" they're really more like really really high tides. You're talking about something that happens over, say, 10-90 minutes, not seconds.

It's a distinction without value I think. There are waves, and many of them. There is a rise in the sea level. For anywhere affected, both certainly matter. Like you mentioned, tsunami isn't a brief event. And here in Japan, they are talking about tsunami waves, not a singular tsunami. And talking about sea level rise and checking the local power poles for sea level indicators from previous tsunami events and floods.

I is absolutely a VERY valuable distinction because the behavior as it affects humans (up to and including killing them) is VERY different.

Regular waves that are a little higher than your seawall might cause some water damage to the buildings right next to it. A tsunami that is a little higher than your seawall will flood your entire town and drown people who are caught in basements.

Re: M8.7 earthquake in Western Pacific, tsunami warning issued

#163

Post by nessex »

brazzy wrote: post #162
nessex wrote: post #158

Earlier quoted context omitted.

It's a distinction without value I think. There are waves, and many of them. There is a rise in the sea level. For anywhere affected, both certainly matter. Like you mentioned, tsunami isn't a brief event. And here in Japan, they are talking about tsunami waves, not a singular tsunami. And talking about sea level rise and checking the local power poles for sea level indicators from previous tsunami events and floods.

I is absolutely a VERY valuable distinction because the behavior as it affects humans (up to and including killing them) is VERY different. Regular waves that are a little higher than your seawall might cause some water damage to the buildings right next to it. A tsunami that is a little higher than your seawall will flood your entire town and drown people who are caught in basements.

Sure, but if you insist it's like a tide you downplay the risk of the initial hit of the wavefronts and the potential for it to slam up the coast or a seawall becoming a larger local wave. And if you insist it's like a wave, you downplay the persistent risk of both follow-up waves and ongoing flooding that won't subside quickly.

So saying it's not waves is dangerous, and saying it's not a sea level rise is dangerous. It's not useful to try and delineate between a tsunami being one of the two when it's in reality an event that consists of both.

(Ignoring that a sea level rise and a long-wavelength wave are the same thing)

Re: M8.7 earthquake in Western Pacific, tsunami warning issued

#164

Post by thenthenthen »

Shanghai has relocated 280.000 people from its coast according to this article: https://mp.weixin.qq.com/s/HLf3PM29IqaWajMhflo_uA

Unclear if its related to the tsunami that is about to hit or the typhoon it is currently experiencing. Wild. Stay safe everyone!

Re: M8.7 earthquake in Western Pacific, tsunami warning issued

#165

Post by jrflowers »

refactor_master wrote: post #69
Waterluvian wrote: post #56

Earlier quoted context omitted.

Sadly we won’t hear from the partners of everyone whose manga didn’t successfully predict a real disaster in a month.

That's because the other mangas forgot to adjust by +/- some 1000 km for location, 25 days, 365 days, 1825 days, or some other arbitrary but possibly nicely divisible number, for when and where it strikes. You also have to conveniently forget the things that don't sell mangas such as annual typhoons, heatwaves, and of course thousands of premature deaths from man-made causes such as pollution and poor lifestyle. Othe…

I’m pretty sure they sell mangas about deaths from man made causes. I’m not an expert but I am fairly certain about this

Re: M8.7 earthquake in Western Pacific, tsunami warning issued

#166

Post by ehnto »

Kozmik1 wrote: post #105
supportengineer wrote: post #94

I have family members who were in Hawaii (Haleiwa) today and they are wondering if they should try to beat the tsunami and get back to their hotel in Waikiki. I am afraid Waikiki will see flooding. I know Duke's and some other restaurants were closing early.

Do not stay in Haleiwa or go to Waikiki. Consult a map, and find some uphill areas above 100ft to drive to. Drive towards Mililani and wait it out in the upland areas. My kids are at camp right now on the North Shore and are being evacuated by bus to Mililani.

I'm sorry you're going through that, it sounds like they will be safe in Mililani.

Re: M8.7 earthquake in Western Pacific, tsunami warning issued

#167

Post by ninetyninenine »

K0balt wrote: post #150
ninetyninenine wrote: post #124

Earlier quoted context omitted.

I don't think he's even right. Like what he is saying is in actuality wrong. He's surprised because he's ignorant. I'm all for people saying stuff the way he says it. He believes it's true, then he should stand behind. But then the consequence is that he needs to be accepting of when people call him out for being utterly wrong.

The difference is that people know what 2m (wind driven) waves look like at their cities seawall. A 2m tsunami is a -completely- different phenomenon, because of its length. Depending upon the underwater geography, a 2m tsunami might flood right over their 3m seawall, and wipe out entire parts of the city, sweeping hundreds of people out to sea. A 2m wind wave will get saltwater spray on cars driving by. They are bot…

I think you’re out of touch. A tsunami is a wave both from a pedantic perspective and an intuitive one and most people aren’t deceived into thinking that tsunamis aren’t dangerous at all because it’s a wave. That’s just made up garbage.

You’re like coming up to me and saying hurricane is not wind because it’s dangerous to think of a hurricane as only wind.

Dude. Nobody is thinking hurricanes are just chill just because hurricanes are wind. This is a fucking non-issue.

I think what you’re trying to say is that the wave length of a tsunami is much longer than the amplitude even though the amplitude is still epically high. But don’t try to conflate this with a safety issue of people dying because somebody called it a “wave” that’s just garbage.

Re: M8.7 earthquake in Western Pacific, tsunami warning issued

#168

Post by Barbing »

refactor_master wrote: post #69
Waterluvian wrote: post #56

Earlier quoted context omitted.

Sadly we won’t hear from the partners of everyone whose manga didn’t successfully predict a real disaster in a month.

That's because the other mangas forgot to adjust by +/- some 1000 km for location, 25 days, 365 days, 1825 days, or some other arbitrary but possibly nicely divisible number, for when and where it strikes. You also have to conveniently forget the things that don't sell mangas such as annual typhoons, heatwaves, and of course thousands of premature deaths from man-made causes such as pollution and poor lifestyle. Othe…

Reminded of the available $1m award from James Randi’s org that was never claimed b/c no one could ever do anything supernatural under reasonable testing conditions.

(Woo is surely possible but all those who can pull it off were gifted abilities that are deactivated by non-monetary incentives)

Re: M8.7 earthquake in Western Pacific, tsunami warning issued

#169

Post by Tor3 »

ninetyninenine wrote: post #130
TylerE wrote: post #79

Earlier quoted context omitted.

Despite the common vernacular calling them "waves" they're really more like really really high tides. You're talking about something that happens over, say, 10-90 minutes, not seconds.

These things are 100% waves. It's not a misnomer. It fits the scientific definition of waves and it fits our intuition of what waves are. These are NOT tides. https://www.noaa.gov/explainers/science-behind-tsunamis

A tsunami absolutely does not fit our intuition of what waves are. It looks like a wave. But it does not stop. It just continues. That little wave goes on an on, farther and farther inland. After an hour it may still go on. It's a nightmare wave, because it doesn't not fit one's intuition of what waves are.
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