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Tsunami warning ends for B.C. after large earthquake strikes off Alaska

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Re: Tsunami warning ends for B.C. after large earthquake strikes off Alaska

#11

Post by wiredfool »

JorgeGT wrote: post #8
dawnerd wrote: post #7

Some buoy data: https://twitter.com/BillKarins/status/955747863140675585

Link to the actual buoy data page: http://www.ndbc.noaa.gov/station_page.php?station=46410&type... Worth noting that other nearby buoys don't show such a dramatic wave: http://www.ndbc.noaa.gov/station_page.php?station=46409&type... Here's a map: http://www.ndbc.noaa.gov/obs.shtml (click on the blinking ones) And here's a map of tsunami-capable tide stations: https://tidesandcurrents.noaa.gov/tsunami/#

I'd be _really_ suspicious of data showing a 10M tsunami in the open ocean. In deep water, they're super long wavelength low amplitude waves, it's only when they interact with the bottom that the wave piles up and gets to large amplitude.

Re: Tsunami warning ends for B.C. after large earthquake strikes off Alaska

#13

Post by mordechai9000 »

I felt it here in Anchorage when I was on my way to bed. It felt like a shallow, rolling earthquake. It reminded me of a quake I experienced in 2001 in Washington state. The shaking went on for what I thought was 30 seconds. My wife woke up but my kids did not.

Within a couple of minutes, I saw the reported magnitude, depth, and location on the USGS earthquake site, https://earthquake.usgs.gov/earthquakes/map/.

About the same time, Google started showing a tsunami alert: https://www.google.org/publicalerts/alert?aid=43774f005241ac...

We are in no danger from a tsunami here in Anchorage.

The alert shows potential tsunami waves arriving at coastal towns over the next couple of hours, with the first potential wave arriving in Kodiak in a few minutes. I have no idea how likely these waves are, but 7.9 is big. I am sure a lot of people are scrambling for high ground now.

God speed and be safe.

Re: Tsunami warning ends for B.C. after large earthquake strikes off Alaska

#15

Post by JorgeGT »

yread wrote: post #10

The tsunami alert: http://ptwc.weather.gov/ptwc/text.php?id=hawaii.TSUHWX.2018.... IF TSUNAMI WAVES IMPACT HAWAII THE ESTIMATED EARLIEST ARRIVAL OF THE FIRST TSUNAMI WAVE IS 0423 AM HST TUE 23 JAN 2018

Times for Alaska:

Estimated tsunami start times for selected sites are;

Kodiak Alaska 145 AM. AKST. January 23.

Elfin Cove Alaska 150 AM. AKST. January 23.

Seward Alaska 155 AM. AKST. January 23.

Yakutat Alaska 200 AM. AKST. January 23.

Sitka Alaska 200 AM. AKST. January 23.

Langara British Columbia 210 AM. AKST. January 23.

Valdez Alaska 215 AM. AKST. January 23.

Cordova Alaska 220 AM. AKST. January 23.

Sand Point Alaska 220 AM. AKST. January 23.

Unalaska Alaska 240 AM. AKST. January 23.

Homer Alaska 250 AM. AKST. January 23.

Craig Alaska 300 AM. AKST. January 23.

Cold Bay Alaska 300 AM. AKST. January 23.

Adak Alaska 305 AM. AKST. January 23.

Tofino British Columbia 340 AM. AKST. January 23.

Shemya Alaska 345 AM. AKST. January 23.

Saint Paul Alaska 400 AM. AKST. January 23.

Source: http://forecast.weather.gov/wwamap/wwatxtget.php?cwa=usa&wwa...

Re: Tsunami warning ends for B.C. after large earthquake strikes off Alaska

#16

Post by porker »

yread wrote: post #10

The tsunami alert: http://ptwc.weather.gov/ptwc/text.php?id=hawaii.TSUHWX.2018.... IF TSUNAMI WAVES IMPACT HAWAII THE ESTIMATED EARLIEST ARRIVAL OF THE FIRST TSUNAMI WAVE IS 0423 AM HST TUE 23 JAN 2018

Do you know why these reports mention Hawaii, rather than (say) Vancouver and other coastal cities nearer to the epicenter, where I would imagine a tsunami would reach first?

Re: Tsunami warning ends for B.C. after large earthquake strikes off Alaska

#17

Post by JorgeGT »

porker wrote: post #16
yread wrote: post #10

The tsunami alert: http://ptwc.weather.gov/ptwc/text.php?id=hawaii.TSUHWX.2018.... IF TSUNAMI WAVES IMPACT HAWAII THE ESTIMATED EARLIEST ARRIVAL OF THE FIRST TSUNAMI WAVE IS 0423 AM HST TUE 23 JAN 2018

Do you know why these reports mention Hawaii, rather than (say) Vancouver and other coastal cities nearer to the epicenter, where I would imagine a tsunami would reach first?

The page is specific to Hawaii, but you can go to http://www.weather.gov/ and in the map, click your region and then "tsunami warning" or "tsunami watch" to see estimated times for other states. This is the tsunami watch notice for coastal areas of Oregon, Washington & California: http://forecast.weather.gov/wwamap/wwatxtget.php?cwa=sew&wwa...

Re: Tsunami warning ends for B.C. after large earthquake strikes off Alaska

#18

Post by porker »

JorgeGT wrote: post #17
porker wrote: post #16

Earlier quoted context omitted.

Do you know why these reports mention Hawaii, rather than (say) Vancouver and other coastal cities nearer to the epicenter, where I would imagine a tsunami would reach first?

The page is specific to Hawaii, but you can go to http://www.weather.gov/ and in the map, click your region and then "tsunami warning" or "tsunami watch" to see estimated times for other states. This is the tsunami watch notice for coastal areas of Oregon, Washington & California: http://forecast.weather.gov/wwamap/wwatxtget.php?cwa=sew&wwa...

Thanks. I hadn't realised that these pages would exclude the coast of Canada either, and they'd have their own site.

https://weather.gc.ca/warnings/index_e.html

Re: Tsunami warning ends for B.C. after large earthquake strikes off Alaska

#19

Post by onnoonno »

JorgeGT wrote: post #8
dawnerd wrote: post #7

Some buoy data: https://twitter.com/BillKarins/status/955747863140675585

Link to the actual buoy data page: http://www.ndbc.noaa.gov/station_page.php?station=46410&type... Worth noting that other nearby buoys don't show such a dramatic wave: http://www.ndbc.noaa.gov/station_page.php?station=46409&type... Here's a map: http://www.ndbc.noaa.gov/obs.shtml (click on the blinking ones) And here's a map of tsunami-capable tide stations: https://tidesandcurrents.noaa.gov/tsunami/#

What I don't get is that nearly all the buoys that have that moving icon "Tsunami alert" show some excitation at the ~9:45GMT mark.

But I would of course expect the buoys that are farther away to only show some kind of peak when the wave actually reaches them. And it looks like they are thousands of km away, so some of them should not even have been reached yet.

Some what is going on there? Is the data time actually shifted and not in GMT but 'earthquake propagation time'? Am I reading the plots wrong?

Re: Tsunami warning ends for B.C. after large earthquake strikes off Alaska

#20

Post by [deleted] »

porker wrote: post #16
yread wrote: post #10

The tsunami alert: http://ptwc.weather.gov/ptwc/text.php?id=hawaii.TSUHWX.2018.... IF TSUNAMI WAVES IMPACT HAWAII THE ESTIMATED EARLIEST ARRIVAL OF THE FIRST TSUNAMI WAVE IS 0423 AM HST TUE 23 JAN 2018

Do you know why these reports mention Hawaii, rather than (say) Vancouver and other coastal cities nearer to the epicenter, where I would imagine a tsunami would reach first?

[deleted]
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