Tsunami watch issued for SF bay area ~8am Friday | Hacker News Reader

Tsunami watch issued for SF bay area ~8am Friday

wcatwc.arh.noaa.gov

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When you will be destroyed:

http://wcatwc.arh.noaa.gov/2011/03/11/lhvpd9/01/webetalhvpd9...

Who will be destroyed:

http://www.socketsite.com/archives/2009/12/san_franciscos_ts...

The technology we have these days and the power of the social web is mind blowing. I hope these links go "viral".

It would be advisable that if you are not directly affected, you should avoid hitting these links. The most important information appears to be static files, but it would be a horrible tragedy if affected visitors were unable to get the information they need because server capacity was exceeded. I carelessly clicked the link to the high-res map in a link above, only to find the server over capacity.

Interesting how Alaska manages to be both first and last on that list.

Mainly because of its long "tail" (stinger?).

Here is the map [1]. The Aleutian islands are hit first, but it seems the big effect is the slowing-down of the wave in very shallow waters. (Here's depth maps: [2][3]). Note the contours -- it takes ~9 hours for the tsunami to cross this small sea (Bering), the same time as it takes to cross the entire Pacific from Japan to British Columbia.

According to [4], shallow-water waves (including tsunamis) have speed proportional to sqrt(depth). Not sure how accurate this approximation is, but it seems to get the order-of-magnitude right.

This FAQ [5] says that much of the energy should be reflected off the continental slope (where it goes from deep to shallow abruptly), so the tsunamis there should be pretty small. The tsunami height-forecast [6] says the same thing.

[1] http://wcatwc.arh.noaa.gov/2011/03/11/lhvpd9/06/ttvulhvpd9-0...

[2] http://www.gebco.net/data_and_products/gebco_world_map/image...

[3] http://disc.sci.gsfc.nasa.gov/oceancolor/additional/science-...

[4] http://oceanworld.tamu.edu/resources/ocng_textbook/chapter16...

[5] http://wcatwc.arh.noaa.gov/faq/ArcticTalkingPoints.htm

[6] http://wcatwc.arh.noaa.gov/2011/03/11/lhvpd9/energylhvpd9-04...

Not just the bay area.

The readers of HN don't just live in CA you know.

It's the entire west coast of the US, Canada and Mexico, including Hawaii and Alaska.

Actually it's the entire west coast of both North and South America and any islands. Also Australia, New Zealand and Asia.

Pretty much the entire Pacific Rim...

Yes, sorry. I just popped it up as soon as I saw it, and focused on SF since I live here.

San Francisco danger is now over. I'm on a Search and Rescue team that was called up by the Sheriff's Office to be on call, but nothing notable happened and everyone is going home.

Wave energy maps http://wcatwc.arh.noaa.gov/2011/03/11/lhvpd9/energylhvpd9-04...

The Santa Cruz newspaper claims it will be quite small in the bay area, fortunately:

The warning covers coastal areas between Point Concepcion to the Oregon-Washington border. While the warning does encourage people in low-lying areas to move inland, officials don't expect the wave that hits the California Coast to be much more than a foot.

edit: Though the NYTimes says (http://www.nytimes.com/2011/03/12/us/12california.html):

Surges could reach three to seven feet along the California, Oregon and Washington coasts. Southern California is expected to be hit by three-foot waves, the authorities said.

According to the linked message, it's still a "watch" for the west coast (including SF), which is "issued to areas which will not be immediately impacted by the tsunami." I don't see where on the page it was upgraded. Can someone point this out?

Update: The updated message is on this page: http://wcatwc.arh.noaa.gov/2011/03/11/lhvpd9/04/messagelhvpd...

Yeah, I couldn't update the URL properly. http://wcatwc.arh.noaa.gov/ is the latest at all times. I'm going to go to bed soon and get up early; I don't anticipate danger here, but it's possible there will be some evacuation downhill from me (94116).

At least according to the latest reports from NOAA, the warning/watch does not apply to the US West Coast at this time:

http://www.weather.gov/ptwc/text.php?id=hawaii.2011.03.11.08...

A good general page to keep open tonight if you are following this story:

http://www.weather.gov/ptwc/

Apologies. It appears my above comment was incorrect:

http://wcatwc.arh.noaa.gov/

Definitely a warning. Here's the most current and clearest map I've seen:

http://wcatwc.arh.noaa.gov/2011/03/11/lhvpd9/05/wwareaslhvpd...

Saturday or Friday? According to the linked page it should begin arriving in Alaska 2 minutes ago, but the list of "Estimated tsunami arrival times" seems to be an empty file.

Friday. And most of the links from that page don't seem to work - their webserver may be down.

Their home page http://wcatwc.arh.noaa.gov/ has a huge warning button - but the page it links to is blank.

Friday. Sorry, it's been a long day. I live on the west side of SF near the ocean; danger unlikely at my elevation, but they're deploying police to keep people away from the beach.

With luck, they're erring on the side of caution; low tide is about 10:30am, so flooding seems unlikely...but this is such a rare event that it's a total guess. Just keep an eye on the weather sites and hope news from Hawaii is not too bad.

I live on Ocean Beach in San Francisco, and apparently there is nothing to worry about, other than to stay off the beach. I'll keep you all posted if things get crazy.

Can you stream some live video with justin.tv?

I've heard it will probably be fine in SF. That said, I'll be over here in Denver.

not much happening here in Hawaii

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