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8.2 magnitude earthquake off Russia with potential to generate a tsunami

wcatwc.arh.noaa.gov

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Re: 8.2 magnitude earthquake off Russia with potential to generate a tsunami

#51

Post by Le_SDT »

pjungwir wrote: post #50
marquis wrote: post #26

Earlier quoted context omitted.

Supplementary data to your link in case of a change: historical tsunami travel times in hours: http://www.ngdc.noaa.gov/hazard/tsu_travel_time_events.shtml... Most relevant: http://www.ngdc.noaa.gov/hazard/icons/1923_0203.jpg

How can a tsunami cross the Pacific in 10 hours? Isn't that as fast as an airliner? Of course I'm not questioning the maps, but isn't that shocking? How does it work?

Such a wave travels at well over 800 kilometres per hour (500 mph) -quoted from wikipedia http://en.wikipedia.org/wiki/Tsunami

Re: 8.2 magnitude earthquake off Russia with potential to generate a tsunami

#53

Post by sp332 »

pjungwir wrote: post #50
marquis wrote: post #26

Earlier quoted context omitted.

Supplementary data to your link in case of a change: historical tsunami travel times in hours: http://www.ngdc.noaa.gov/hazard/tsu_travel_time_events.shtml... Most relevant: http://www.ngdc.noaa.gov/hazard/icons/1923_0203.jpg

How can a tsunami cross the Pacific in 10 hours? Isn't that as fast as an airliner? Of course I'm not questioning the maps, but isn't that shocking? How does it work?

It's not a wave that physically moves as a single mass of water across the ocean. It's a shockwave that propagates through the ocean.

Re: 8.2 magnitude earthquake off Russia with potential to generate a tsunami

#55

Post by cema »

Grue3 wrote: post #40
thresh wrote: post #8

Being in Moscow, which is 6000+ km away from the epicentre of the earthquake, we still felt the tremors... Fascinating.

I am also in Moscow and I call bullshit on this.

Why? I have heard (I mean, read) people reporting having felt slight tremors. Example ([ru]): http://nina-petrovna.livejournal.com/797021.html

Re: 8.2 magnitude earthquake off Russia with potential to generate a tsunami

#56

Post by Thrymr »

sp332 wrote: post #53
pjungwir wrote: post #50

Earlier quoted context omitted.

How can a tsunami cross the Pacific in 10 hours? Isn't that as fast as an airliner? Of course I'm not questioning the maps, but isn't that shocking? How does it work?

It's not a wave that physically moves as a single mass of water across the ocean. It's a shockwave that propagates through the ocean.

It's not a shock wave, it's a shallow water wave (because the wavelength is much larger than the depth of the ocean). The speed depends on depth [v = sqrt(g*H)]; for typical deep Pacific (5000 m), that is ~220 m/s or 500 mph.

Re: 8.2 magnitude earthquake off Russia with potential to generate a tsunami

#57

Post by slashedzero »

vsbuffalo wrote: post #19

We felt a small earthquake in Davis, CA earlier tonight. Active day for our earth! I quite like earthly events like this — they really make one realize how minuscule we are.

Only half of us felt it here in Sacramento, CA. It seriously just felt like someone slammed a door very hard.

Re: 8.2 magnitude earthquake off Russia with potential to generate a tsunami

#58

Post by runjake »

tricolon wrote: post #30
toddrew wrote: post #27

Earlier quoted context omitted.

These messages are always in caps to send faster over slower systems. http://www.alternatewars.com/BBOW/Computing/Capital_Letters.... I spent a decade as a communicator in the navy and radio teletype is still the primary method of communication at sea.

That makes sense. However, I argue that the NOAA could serve their warnings on the web in all lowercase for the sake of readability. Then again, that could be a quick hack for someone.

It's more readable in all caps, which is why they and the military do it this way. If it were all lowercase thing like Is and ls and 1s would get confused.

Re: 8.2 magnitude earthquake off Russia with potential to generate a tsunami

#59

Post by btilly »

Grue3 wrote: post #40
thresh wrote: post #8

Being in Moscow, which is 6000+ km away from the epicentre of the earthquake, we still felt the tremors... Fascinating.

I am also in Moscow and I call bullshit on this.

I have experienced plenty of earthquakes where one person felt it quite strongly and another living nearby didn't.

How easy it is to feel varies depending on what floor you're on, how well constructed your building is, what kind of ground you're standing on, etc, etc, etc.

Furthermore at that distance the earthquake should be a slow roller, which means that someone who is focused on something might not notice while another person in the same room could notice, realize how much motion there is, and freak out. I've been there as well - as the person watching a movie who ignored an earthquake that everyone outside of the movie was quite aware of.

So the fact that you live in Moscow and didn't feel it is not grounds to call BS on someone else claiming that they felt it.

Re: 8.2 magnitude earthquake off Russia with potential to generate a tsunami

#60

Post by tomkarlo »

tricolon wrote: post #30
toddrew wrote: post #27

Earlier quoted context omitted.

These messages are always in caps to send faster over slower systems. http://www.alternatewars.com/BBOW/Computing/Capital_Letters.... I spent a decade as a communicator in the navy and radio teletype is still the primary method of communication at sea.

That makes sense. However, I argue that the NOAA could serve their warnings on the web in all lowercase for the sake of readability. Then again, that could be a quick hack for someone.

NOAA / NWS advisories tend to have a lot of proper names. It looks really wacky if you just lower-case them (and it's non-trivial to convert them to proper capitalization automatically.)

(I tried to do this back in about 1999. I don't think it's gotten much easier, although having geo APIs might help somewhat.)

Also, apparently there's some international standards around this kind of info that require it to be upper case: http://www.motherjones.com/kevin-drum/2012/10/blame-united-n...

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