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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

#251

Post by K0balt »

lief79 wrote: post #246
K0balt wrote: post #231

Earlier quoted context omitted.

So, I’m sorry that I evidently didn’t manage to convey my point effectively. The problem is that wave is accompanied by a measurement that deceptively buries the lede. Everyone knows hurricanes are wind. So they look for the wind speed to understand the threat. And it’s effective at characterizing the threat. A 100mph wind is going to be similarly destructive as any other 100mph wind. It works and is semantically and…

My understanding is the most deadly/destructive parts of hurricanes are usually: 1. the storm surge, the potential wall of water brought by the continuous winds and waves near the shore, followed by 2. the flooding from heavy rains, then 3. followed by the wind. So your example might also be hitting the same issue you're trying to avoid. Note, the worst storm surge is from the eye towards the side where the winds are…

Good points. Where I am at it’s mostly the wind because I am a well drained higher elevation, so I’m sure that coloured my perception. But you are right, the storm surge and flooding also do a great deal of damage.

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

#252

Post by K0balt »

throwup238 wrote: post #250
K0balt wrote: post #150

Earlier quoted context omitted.

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…

Nitpick: while what you say is generally true, there are several scenarios that can create true dramatic “wall of water” tsunami waves that have leading slopes of 45-90 degrees and heights in the tens of meters. The most obvious (but relatively rare) are tsunamis amplified by submarine canyons and other coastal bathymetry like the Nazare submarine canyon famous for the biggest waves on the planet (50+ footers are com…

Oh yes! It’s absolutely true that underwater geography can steepen the wave front and amplify the height, sometimes by orders of magnitude. The deep water height of a tsunami wave is often a lot different from what you will see at the coastline.

An entertaining anecdote from the pre- smartphone era:

I sailed to the site near Chenega bay where the earthquake wiped out the village in 1958. We got permission from the elders at the Chenega bay village to land at the island, and it was extremely humbling to see the high water mark from the coastline, and to see the wreckage of boats far, far up on mountainsides.

I’m not a big believer in supernatural stuff, and there are plenty of alternative explanations, but it still freaks me out a bit that the photos we took (aside from the digital ones) did not develop any images of the village site. It was white as if it had been overexposed, even in the case of 1/2 frames. On both disposable cameras. Other photos from the same day, taken in other directions, turned out fine. The digital camera fell overboard in 500 fathoms, so we lost those photos the next day.

As for how exactly this could happen in any reasonable version of events, I’ve got nothing. I guess sometimes chance events line up just right to make for a good story.

Interestingly, there are big tidal bores frequently in Turnagain arm, with 1-3m being common. I’ve seen people surfing it with wetsuits in the ice cold water, getting a run of several miles lol.

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

#253

Post by smcin »

dehrmann wrote: post #153
lordswork wrote: post #6

https://www.conservation.ca.gov/cgs/tsunami/maps is getting a hug of death :( If anyone gets on, please post a screenshot.

This also happened during the tsunami last year. Does anyone know of a map app that works offline and can save overlays like this?

No, but an archive.org for US govt webpages like tsunami.gov (including dynamic content) seems like something that is currently needed.

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

#255

Post by throwup238 »

K0balt wrote: post #252
throwup238 wrote: post #250

Earlier quoted context omitted.

Nitpick: while what you say is generally true, there are several scenarios that can create true dramatic “wall of water” tsunami waves that have leading slopes of 45-90 degrees and heights in the tens of meters. The most obvious (but relatively rare) are tsunamis amplified by submarine canyons and other coastal bathymetry like the Nazare submarine canyon famous for the biggest waves on the planet (50+ footers are com…

Oh yes! It’s absolutely true that underwater geography can steepen the wave front and amplify the height, sometimes by orders of magnitude. The deep water height of a tsunami wave is often a lot different from what you will see at the coastline. An entertaining anecdote from the pre- smartphone era: I sailed to the site near Chenega bay where the earthquake wiped out the village in 1958. We got permission from the el…

> Interestingly, there are big tidal bores frequently in Turnagain arm, with 1-3m being common. I’ve seen people surfing it with wetsuits in the ice cold water, getting a run of several miles lol.

That’s going on the bucket list! How dangerous is it? If you biff it and get caught by the wave can you just dive under the wavefront and come up behind it like on a beach?

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

#256

Post by somat »

tracerbulletx wrote: post #242
Thrymr wrote: post #141

Earlier quoted context omitted.

So are tides.

Perhaps we can just go back to calling them tidal waves. Which is also ambiguous. I guess if I had any point it's just that it's not colloquial to call tsunami waves, its technical. If anything distinguishing based on how they feel compared to regular wind waves is more colloquial.

Honestly tidal wave, a wave that comes in like the tide, might actually be a better term than tsunami (lit Harbor Wave) A wave that destroys your harbor? A wave found in your harbor(a place where there are usually no waves)? What if you are not in a harbor, do you still get a wave?

I am just having a bit of linguistic fun. Tsunami is a great clear distinct term for what can be a very destructive event.

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

#257

Post by indigodaddy »

smcin wrote: post #254
indigodaddy wrote: post #48

Agenda-free TV channel on YouTube has pretty good live/current coverage right now

Which TV channel please? Link or name?

He doesn't look to be live right now, but here is the channel: https://youtube.com/@agendafreetv?si=ROE1VAC1D6IlCcXl

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

#258

Post by smcin »

indigodaddy wrote: post #257
smcin wrote: post #254

Earlier quoted context omitted.

Which TV channel please? Link or name?

He doesn't look to be live right now, but here is the channel: https://youtube.com/@agendafreetv?si=ROE1VAC1D6IlCcXl

Oh that's actually the name, I thought it was a diss on most media! Thanks.

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

#259

Post by JCharante »

Amadiro wrote: post #209
sugarpimpdorsey wrote: post #45

Earlier quoted context omitted.

Japanese news reporting during disaster scenarios is something to behold. The screen is filled with data and blinking like a Bloomberg Terminal.

Also when you visit most japanese websites you can see this phenomenon. I've read an explanation once that this is because culturally, japanese people perceive a wealth of information and choice as being re-assuring and trustworthy, while most westerners feel more re-assured by seeing less content and choice presented in a more minimalist kind of way.

oh I hate minimalistic UIs, I think I might have just found my people

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

#260

Post by pezezin »

Symbiote wrote: post #245
ccozan wrote: post #240

Earlier quoted context omitted.

and the cables, the cables hanging from everywhere! ( btw, has anyone noticed in anime there are always frames of street cabling? Like those cylindrical transformes and thick cables. Almost cyberpunk! )

The transformers are a result of a the lower voltage (also used in America), for efficiency and to keep the required voltage the transformer needs to be nearer to the house.

We also have transformers in Europe, but they are hidden. Which incidentally makes them more reliable, as they are not exposed to the elements.
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