Earthquake!

[Samurai_Jerk]

That was very surreal. My company issues iPhones so everyone's warning went off at the same time with the same alarm sound an voice saying "Jishin desu."

[matsuki]

That was very surreal. My company issues iPhones so everyone's warning went off at the same time with the same alarm sound an voice saying "Jishin desu."

My jishin app didn't do shit but the boss has an iphone....but the timing of "jishin desu" was a "no shit Sherlock" moment.

[legion]

Same here, I think the sudden eruption of alarms all over the room is more likely to cause panic than the quake itself.

Weird concept, your phone telling you the ground is shaking, like you wouldn't notice otherwise

[yanpa]

Quake was a too close to Tokyo for the warnings to be of much use. Out-of-contract garakei got a warning but I was in a different part of the house.

[yanpa]

Same here, I think the sudden eruption of alarms all over the room is more likely to cause panic than the quake itself.

Weird concept, your phone telling you the ground is shaking, like you wouldn't notice otherwise

I pity the poor sods who develop/maintain this system - if there hadn't been an alarm people would still be complaining...

[Coligny]

Nothing here... Nice knowing you guyz...

[matsuki]

Same here, I think the sudden eruption of alarms all over the room is more likely to cause panic than the quake itself.

Weird concept, your phone telling you the ground is shaking, like you wouldn't notice otherwise

I pity the poor sods who develop/maintain this system - if there hadn't been an alarm people would still be complaining...

I guess the point is the alarms are useless unless it gives you enough time to take appropriate action. Alarms during the earthquake just hollywood up the panic. (wouldn't have wanted to be at SJ's office for that)

[wagyl]

I guess the point is the alarms are useless unless it gives you enough time to take appropriate action. Alarms during the earthquake just hollywood up the panic. (wouldn't have wanted to be at SJ's office for that)

How much time becomes "enough time"? I think you are asking a little too much of what these things are technically capable of.

The biggest issue I had with the alarms three years ago Edit: four years ago. Time flies when you are having fun with mildly heightened radioisotropes is that with my model of phone, if you get into the habit of ignoring them (because they are ringing during the event, not before) then you don't get any other notifications of incoming calls or morning wake-up alarms until you look at the damn thing and clear it off the screen.

[Samurai_Jerk]

Same here, I think the sudden eruption of alarms all over the room is more likely to cause panic than the quake itself.

Weird concept, your phone telling you the ground is shaking, like you wouldn't notice otherwise

I pity the poor sods who develop/maintain this system - if there hadn't been an alarm people would still be complaining...

I guess the point is the alarms are useless unless it gives you enough time to take appropriate action. Alarms during the earthquake just hollywood up the panic. (wouldn't have wanted to be at SJ's office for that)

In theory they can give you enough time if you're far enough away from the epicenter. Saitama's just a bit too close to Tokyo.

[matsuki]

I guess the point is the alarms are useless unless it gives you enough time to take appropriate action. Alarms during the earthquake just hollywood up the panic. (wouldn't have wanted to be at SJ's office for that)

How much time becomes "enough time"? I think you are asking a little too much of what these things are technically capable of.

Even only a few seconds could probably stop you from doing a lot of things that could kill/injure you. (which is why I agree they are generally a good thing)

The biggest issue I had with the alarms three years ago is that with my model of phone, if you get into the habit of ignoring them (because they are ringing during the event, not before) then you don't get any other notifications of incoming calls or morning wake-up alarms until you look at the damn thing and clear it off the screen.

I just noticed mine locked itself down...all your keitai functions are belong to jishin warning!

[wagyl]

I guess the point is the alarms are useless unless it gives you enough time to take appropriate action. Alarms during the earthquake just hollywood up the panic. (wouldn't have wanted to be at SJ's office for that)

How much time becomes "enough time"? I think you are asking a little too much of what these things are technically capable of.

Even only a few seconds could probably stop you from doing a lot of things that could kill/injure you. (which is why I agree they are generally a good thing)

Well, in that case, you should move further from the epicenter! Don't blame your choice of location on the alarm technicians!

[Yokohammer]

I'd much rather have that alarm thing than not. Sometimes you get quite a bit of time ... if you can consider around 10 seconds quite a bit of time. Still, it does give you a chance to brace yourself and at least start moving in the right direction.

When that early-morning quake happened up in Iwate (I think it was) a couple of weeks ago the alarm went off and we were out of bed and in the hallway before shit started shaking.

Definitely a good thing, and it'll probably get more responsive/accurate as time goes on.

BTW: didn't feel a thing up here.

[Coligny]

Same here, the big T is in such a different motion pattern that if the alarm ring and the quake is strong enough to be felt we have a good 5-10 second delay.
Enough to shutdown cooking tables, or climb down a ladder or get away from a know unsecured zone of the house.
But hey, if it don't give a 5 days reminder send a fax and clean the shitter might as well shut down the system...

[yanpa]

Definitely a good thing, and it'll probably get more responsive/accurate as time goes on.

Until there's a quantum leap in reliable earthquake *prediction*, it won't be physically possible to provide advance warnings of nearby quakes...

One use-case for providing an alarm even if it arrives at the same time as (or a few milliseconds before) the quake is for people in places where the shaking may not be immediately apparent. Such as outside.

[Yokohammer]

Definitely a good thing, and it'll probably get more responsive/accurate as time goes on.

Until there's a quantum leap in reliable earthquake *prediction*, it won't be physically possible to provide advance warnings of nearby quakes...

One use-case for providing an alarm even if it arrives at the same time as (or a few milliseconds before) the quake is for people in places where the shaking may not be immediately apparent. Such as outside.

This isn't a case of "prediction," it's a matter of how fast you can detect when a quake has started and broadcast that information to an alarm system.

[Coligny]

Ehmmm it's a matter of delta between the speed of the p and s waves. Like lightning and thunder.
The closer you are from the event, the closer together both happens.

The further you are... P waves much quicker reach you much earlier than the slower s waves. Since alarms are triggered by p waves... Those at the point of the quake are fucked...

[Yokohammer]

Ehmmm it's a matter of delta between the speed of the p and s waves. Like lightning and thunder.
The closer you are from the event, the closer both happens.

The further you are... P waves much quicker reach you much earlier than the slower s waves. Since alarms are triggered by p waves... Those at the point of the quake are fucked...

And where are the P waves currently being detected?

I'm guessing it's at or near the surface, and the speed of "detection" will depend on how close one of the detectors happens to be to the epicentre. The closer the faster, no? Increasing the density of the detector network is the obvious first step ... and I believe they're working on that.

And for the future, how about detecting the event closer to the point of occurrence, say 50km below the surface like the quake today? This is where I'm saying I think the technology will improve. Land based sensors may not be the answer. Some form of satellite detection, perhaps?

The system will be refined.
There is still room for improvement.
We're not done yet.
You can count on that.

[Coligny]

In japan the # of monitoring post is quite consequent. The wiki say need a p wave detection from at least 2 of the 4200+ stations with a ~5 expected strength to trigger an alarm...

Good wiki dere :
http://en.m.wikipedia.org/wiki/Earthqua ... ing_(Japan)

[Taro Toporific]

Damn that was big long one!

[Taro Toporific]

Damn that was big long one!

Japan Earthquake
Magnitude 8.5 Intensity 5+ earthquake 20:24 May-30 JST at Ogasawara-shoto Seiho-oki (27.9N/140.8E) http://bit.ly/1PUzNzr

緊急地震速報]20:25:03現在
第8報　予報
発生：20:23:11
震源：小笠原諸島西方沖　28.0N 140.1E　560km
規模：M8.0　最大不明
予想：-　-　-
確度：-

CGQBHMjUQAEQf2D.png

[Yokohammer]

Even felt that one up here. Big but distant-slow.


~ Tapatalking ~

[Taro Toporific]

Even felt that one up here. Big but distant-slow.

Started as just a jiggle, but it ended up no giggle.

The Japan Times
BREAKING: Strong long earthquake shakes Tokyo area; no tsunami alert issued. M8.5, +5 on shindo scale, with epicenter near Ogasawara Island.

[Coligny]

image.jpg

Need a recount...
Felt absolutely nothing ... While reading in my bunk.

[wagyl]

I don't think I have ever seen an epicenter depth of 590 km before.

[Yokohammer]

I don't think I have ever seen an epicenter depth of 590 km before.

Surprised me too. That is really deep.


~ Tapatalking ~

[yanpa]

migjt only have been shindo 4 in Tokyo, but felt mighty powerful.

[Coligny]

5 days between them quakes ...

[wagyl]

Yanpa, do you have that "¿Qué?" script operating yet? viewtopic.php?f=11&t=29654&p=328471#p328471

[Russell]

Just switched on the TV and got surprised.

That was a strong one. Didn't feel anything here, though.

How is the situation in Tokyo? Any damage?

[yanpa]

I noticed some lightweight goods on a shop shelf had forfeited their vertical position.

Other than that the Yamanote line and all the other JR lines running down its eastern part are still out of service. Presumably they're out looking for fallen catenery masts.