[HN Gopher] Tsunami Warning for Northern California
___________________________________________________________________
Tsunami Warning for Northern California
Author : adastra22
Score : 268 points
Date : 2024-12-05 18:58 UTC (4 hours ago)
(HTM) web link (www.tsunami.gov)
(TXT) w3m dump (www.tsunami.gov)
| epicureanideal wrote:
| Any idea how far it would reach, what cities would actually be
| affected?
| mdhb wrote:
| https://forecast.weather.gov/wwamap/wwatxtget.php?cwa=usa&ww...
| mrnaught wrote:
| Google maps has this neat map :
| https://www.google.com/maps/@40.4392216,-123.0674806,6z/data...
| saltcured wrote:
| The boundaries on this look very odd to me. I wonder what
| kind of model and terrain resolution they use for this
| forecast.
|
| It seems very odd how some quite low lying shore areas in the
| SF Bay are excluded while other areas are painted over very
| high elevations including the SF peninsula and
| Oakland/Berkeley hills.
| plorkyeran wrote:
| For the East Bay it looks like they drew a very rough
| outline of the contour of the hills and then pushed it an
| extra half mile or so inland, which results in some clearly
| safe spots landing inside the line.
| anon84873628 wrote:
| The SF bay and Santa Cruz are on the south end of the effected
| area. On past occasions like this, waves have washed over low
| beaches and lagoons, but not come remotely close to overtopping
| the coastal terrace cliffs.
| photochemsyn wrote:
| > Estimated tsunami start times for selected sites are;
|
| Fort Bragg California 1110 AM.PST. December 5.
|
| Crescent City California 1120 AM.PST. December 5.
|
| Port Orford Oregon 1120 AM.PST. December 5.
|
| Brookings Oregon 1125 AM.PST. December 5.
|
| Charleston Oregon 1140 AM.PST. December 5.
|
| San Francisco California 1210 PM.PST. December 5.
|
| The tsunami warning will remain in effect until further notice.
| Refer to the internet site tsunami.gov for more information.
| milleramp wrote:
| Appears to be due to a 7.0 earthquake off the northern coast of
| California
| mdhb wrote:
| Estimated tsunami start times for selected sites are;
|
| Fort Bragg California 1110 AM.PST. December 5.
|
| Crescent City California 1120 AM.PST. December 5.
|
| Port Orford Oregon 1120 AM.PST. December 5.
|
| Brookings Oregon 1125 AM.PST. December 5.
|
| Charleston Oregon 1140 AM.PST. December 5.
|
| San Francisco California 1210 PM.PST. December 5.
| duxup wrote:
| How do Tsunami Warnings work?
|
| For a Midwesterner a Tornado Warning requires someone to see it,
| or be be detected by radar. It's usually a good indicator that it
| is highly likely that the tornado exists and it is actively doing
| its thing somewhere. Warnings are pretty specific and almost
| always involve the thing happening.
|
| Tsunami though, would it have to exist as far as seeing it on the
| coast, or is this more of a "conditions are ripe" kind of event?
|
| I wonder if the Tsunami situation with all the under water
| variables is a lot more unknown?
| whimsicalism wrote:
| i believe they have monitoring deep ocean buoys
| pageandrew wrote:
| How do these detect tsunamis? They must be observing
| elevation changes, right? Is that GPS based?
| whimsicalism wrote:
| i think they monitor pressure waves somehow
|
| here is an interactive map, looks like some of them are
| picking up something https://www.ndbc.noaa.gov/obs.shtml?la
| t=13&lon=-173&zoom=2&p...
| hinkley wrote:
| Triangulation can tell you where a point is between three
| sources but you need four to determine elevation, because
| it's not the radius of a circle but the radius of a sphere.
|
| But at sea there's not much to obscure satellite signals so
| I believe resolving buoy position was a solved problem back
| when gps car navigation still sucked balls because tall
| buildings make everything harder. You need a lot more
| satellites to see three or four at the same moment.
| adastra22 wrote:
| It is all 100% automatic based on earthquake data.
| spondylosaurus wrote:
| We collect a boatload of earthquake data, too. Years ago I
| subscribed to USGS email alerts for my area as a fun novelty
| thing, but has to unsubscribe because there were too many of
| them! (This was in SoCal, so tons of tiny quakes all the
| time.)
| netcraft wrote:
| I am no expert, but I believe they are triggered anytime there
| is an underwater earthquake. Often these still do not produce
| any tsunami, but they are issued out of an abundance of
| caution, there isnt generally a way to see if there really is
| or isnt until it actually shows up on the coast
| dragonwriter wrote:
| https://tsunami.gov/?page=message_definitions
|
| A warning, the highest level, means "a tsunami with the
| potential to generate widespread inundation is imminent,
| expected, or occurring."
|
| The actual criteria are here:
|
| https://tsunami.gov/operations/opsmanual.pdf (Section 3)
|
| Note that the level of initial alert for an area is influenced
| by both the magnitude of the quake and the distance/time from
| quake to the area the alert covers.
|
| > I wonder if the Tsunami situation with all the under water
| variables is a lot more unknown?
|
| Yeah,I don't think there is anything as clear and with the
| coverage of radar for tsunamis, and warning when you see one is
| going to be too late.
| whimsicalism wrote:
| Is it like.. still safe to be driving on 101/280 during this?
| adastra22 wrote:
| 280 is for sure safe.
| erik_seaberg wrote:
| The warning went at least as far as the inland side of
| Fremont, which seemed extreme.
| reducesuffering wrote:
| I, as another Eric in Fremont, also seemed bewildered when
| I got this warning
| adastra22 wrote:
| This webcam should let us know in a few minutes if this is real:
| https://www.pacificblue.biz/noyo-harbor-webcam/
|
| Edit: arrival time has come and gone. No indication of movement
| in water level.
| duxup wrote:
| Looks nice, I want to go have lunch there (without the
| Tsunami).
| adastra22 wrote:
| For sure!
| stickfigure wrote:
| I have had lunch there, can confirm. Though I think the best
| food in the harbor is at Noyo Harbor Inn. The Wharf was
| pretty good for an old-school seafood restaurant.
| jjulius wrote:
| Likewise. Stopped in on a whim, and was pleasantly
| surprised. Delightful little area in that harbor, and the
| food was better than expected. I appreciate the surprise
| nostalgia from this webcam. :)
| choppaface wrote:
| There are a handful of good restaurants (e.g. Sea Pal Cove)
| and a nice off-leash beach beach there despite it being a
| very sleepy corner of the small city.
| whalesalad wrote:
| Lots of boats beginning to move out
| kccoder wrote:
| I'm seeing lots of boats exiting the harbor, presumably to
| enter the ocean where any tsunami effects will be lessened?
| topher515 wrote:
| From the link in other threads: https://www.tsunami.gov/event
| s/PAAQ/2024/12/05/so1aq0/1/WEAK...
|
| * Boat operators, * Where time and
| conditions permit, move your boat out to sea to a
| depth of at least 180 feet. * If at sea avoid
| entering shallow water, harbors, marinas, bays,
| and inlets to avoid floating and submerged debris
| and strong currents.
| adastra22 wrote:
| Presumably, but this is near the focal point of the
| earthquake, and surge should have arrived 8 minutes ago as I
| write this. No indication of any water level change. I think
| this was a false positive.
| chrisbrandow wrote:
| typically, yes. Tsunamis are usually unnoticeable away from
| the shore. They aren't like a massive, traveling, cresting
| wave. They are usually a pulse of high energy that can move a
| lot of water just a few feet, which can be devastating when
| it reaches the shore because it is relentless as it moves up
| to that height.
| andrewinardeer wrote:
| How does one livestream a nest camera feed?
| DiggyJohnson wrote:
| Down now. Went out around 14:21 ET
| gbnwl wrote:
| It's back
| jazzyjackson wrote:
| I think it just times out after a while, comes back up
| refreshing the page, but the page seems to be getting hugged
| now. A twitch stream it ain't.
| sitkack wrote:
| Here is a yt link if that site gets overloaded
| https://www.youtube.com/watch?v=ESsx4MdloQw
| gbnwl wrote:
| Well I didn't see a Tsunami but thanks to this thread I do have
| a few nice live streams of pleasant water views going. Kind of
| relaxing tbh.
| dylan604 wrote:
| That's pretty much how I felt about the surfing portion of
| this year's Olympics
| jrnichols wrote:
| I loved the days when people could/would set up webcams like
| this. Just to see outside and share it with others. They're
| getting so much harder to find.
|
| This is quite relaxing, I agree. Here's a couple from
| Pacifica, CA for you.
|
| https://www.pacificaview.net/livecam/
| hindsightbias wrote:
| https://www.window-swap.com/Window
| danenania wrote:
| surfline.com has them all over the world, but you have to
| pay $9/mo to watch them (I have a sub for surfing info).
| They have a 24h rewind feature which is pretty cool. People
| use it sometimes for video of themselves surfing, but I
| guess it would also be useful for random events like
| tsunamis.
|
| On that note, I checked feeds at both Ocean Beach and Linda
| Mar at the predicted time but didn't see anything unusual,
| except that they apparently made all the surfers get out
| (first time I've ever seen Linda Mar empty of surfers
| during daylight hours apart from big storms/flat spells).
| OB had a bunch of spectators lined up on the dunes... an
| interesting reaction to a tsunami warning is "let's go to
| the beach and watch!".
| dboreham wrote:
| Minor point, but the web site (under "Origin time:") displays a
| time stamp in _local_ time (local to the web browser viewing the
| page), but doesn 't tell the user that's what it's doing. imho
| very confusing.
|
| Edit. Noticed it says in small print lower down the page: "Note:
| Times are local to your browser, unless otherwise indicated" so
| either I missed that before, or someone on this thread fixed
| it...
| postepowanieadm wrote:
| Stay safe people.
| whalesalad wrote:
| FORECASTS OF TSUNAMI ACTIVITY
| ----------------------------- * Tsunami activity is
| forecasted to start at the following locations at the
| specified times. FORECAST
| START SITE OF TSUNAMI ----
| ---------- * California Fort Bragg
| 1110 PST Dec 5 Crescent City 1120 PST Dec 5
| San Francisco 1210 PST Dec 5 * Oregon
| Port Orford 1120 PST Dec 5 Brookings 1125
| PST Dec 5 Charleston 1140 PST Dec 5
|
| via
| https://www.tsunami.gov/events/PAAQ/2024/12/05/so1aq0/1/WEAK...
| sytse wrote:
| I should have hit Fort Bragg by now but I'm not seeing that on
| https://www.noyocenter.org/live-web-cam
|
| The earthquake was real but it is probably really hard to
| predict if that leads to a tsunami.
| lumost wrote:
| Is that webcam guaranteed to be a live/up to date feed?
| regardless I'd imagine there to be some confirmation by now.
| OsrsNeedsf2P wrote:
| There's a timestamp in the top right, so yes. Looks like no
| tsunami
| lawlessone wrote:
| I just seen two people walk by... seems like a bit of a
| gamble to do that.
| s1artibartfast wrote:
| I was watching the crescent city webcam and watched the
| fishing boats rushing out of the harbor after the quake. The
| webcam is now down, so I hope they made it.
|
| Crescent city has a long history of being devastated by
| norcal quakes due the the bathymetry and costline profile.
| pimlottc wrote:
| Direct link to their live cam on YT:
|
| https://www.youtube.com/live/ESsx4MdloQw?si=PQSwV06GsYfwOZPj
| Polizeiposaune wrote:
| There is now an updated notice timestamped at 11:24 Pacific
| time:
|
| https://www.tsunami.gov/events/PAAQ/2024/12/05/so1aq0/2/WEAK...
|
| which (still) says:
|
| * No tsunami observations are available to report.
|
| And another one at:
| https://www.tsunami.gov/events/PHEB/2024/12/05/24340001/2/WE...
|
| intended for a worldwide audience which says: *
| THERE IS NO LONGER A TSUNAMI THREAT FROM THIS EARTHQUAKE.
| Polizeiposaune wrote:
| Appears to be due to this M7.0 earthquake off the coast of
| California near Eureka, CA:
|
| https://earthquake.usgs.gov/earthquakes/eventpage/us7000nw7b...
|
| (early estimates of magnitude tend to vary; looks like magnitude
| estimates are currently ranging from 6.0 to 7.3)
| mkolodny wrote:
| PRELIMINARY EARTHQUAKE PARAMETERS
| ---------------------------------
|
| * The following parameters are based on a rapid preliminary
| assessment of the earthquake and changes may occur.
|
| * Magnitude 7.3 * Origin Time 0944 AKST Dec 05 2024 1044 PST
| Dec 05 2024 1844 UTC Dec 05 2024 * Coordinates 40.3 North 124.7
| West * Depth 8 miles * Location 45 miles SW of Eureka,
| California 215 miles NW of San Francisco, California
| sytse wrote:
| Cool to see that Google Docs gives me this warning too
| https://imgur.com/a/B6qSboV
| WhereIsTheTruth wrote:
| That's it? "Tsunami Warning", no context? no advice on what to
| do to avoid panic?
| andrewinardeer wrote:
| I would suggest that this is based on location of the IP
| address. I'm not getting it on the other side of the world.
| Pigalowda wrote:
| Presumably a person receiving such an alert would have a
| heightened sense of self preservation and would investigate
| further..
| clueless wrote:
| any chance of a live feed of an affected beach?
| sbohacek wrote:
| Crescent city live web cam. Currently showing boats going out to
| sea.
|
| https://www.iplivecams.com/live-cams/crescent-city-harbor-di...
| quietthrow wrote:
| Interesting observation: I am in a circumstance where I am
| transitioning from an Android phone (Samsung Galaxy) to a iPhone.
| I observed that android phone alerted me about an earthquake and
| that I should be ready to feel tremors. To my surprise as I was
| pondering how this system works - especially wrt to latency -
| where it alerts me head of time, I then fell small tremors in 2
| or 3 seconds after the alert. The tremors were very small and I
| would not have noticed it if it weren't for the alert. ~10 (may
| 15 minutes) later, the IPhone gave a tsunami warning which I take
| it was due to the earthquake.
|
| What I was surprised by is how behind the iPhone was. I expected
| iPhone to be on par with android in terms of safety alerts.
|
| Anybody know if there is a way to get the early alerts on iPhone
| like I did on the android phone?
|
| In general my impression of Android is that it's quite 'leaky'
| and apps can abuse it quite easily and iPhone is more secure.
| Would love to hear thoughts on this or point me to resources that
| address this question.
| tshaddox wrote:
| Sounds like it could have just been a quirk. I've had a couple
| of iPhone earthquake alerts around 0-2 seconds before feeling
| it, so it's definitely not a general problem with iPhones. I've
| also had many more of the AMBER alerts and test broadcast
| alerts where everyone in the room receives them at the same
| instant regardless of phone manufacturer.
| trial3 wrote:
| The Verge's Vergecast podcast did a pretty in-depth story in
| the second half of an episode about this that was fascinating
| [0]
|
| tldl: I do think the recommendation was installing the official
| ShakeAlert app
|
| [0] https://podcasts.apple.com/mu/podcast/two-possible-
| futures-f...
| HuoKnight wrote:
| I have an android (pixel 7), and I got not alert for earthquake
| or tsunami. IOS users around me got alerted for the magnitude
| 7, not entirely sure about the tsunami
| therein wrote:
| My iPhone was 3-4 minutes behind my Android device on this
| one.
| raggi wrote:
| yep, the iphone is comparably terrible in this area, even with
| the myshake app
| whimsicalism wrote:
| i've also observed android to be consistently faster on these
| alerts
| dekhn wrote:
| google maintains an open TCP connection on every android
| device (IIRC it's part of GMSCore) which allows them to push
| to phones with extremely low latency.
| mort96 wrote:
| It doesn't sound like the iPhone was behind, but rather warning
| about something else? It's interesting that Android didn't warn
| about the tsunami at all, even though that sounds more
| important than the barely noticable tremors you describe.
| gamblor956 wrote:
| Why would the Android give a notification for a tsunami that
| never happened?
|
| Androids also give tsunami warnings, when appropriate. There
| was 1 issued just a few weeks ago after an off-shore
| earthquake in SoCal.
| powersnail wrote:
| My Android did give me a tsunami warning this morning
| though, but no earthquake warning.
| lern_too_spel wrote:
| The tsunami warning was in effect all the way down to
| Santa Cruz. The earthquake alert is sent only if you are
| expected to experience some particular level of shaking
| or higher in your location.
| JCharante wrote:
| I'm not sure what you need to configure, but you can definitely
| get iPhone alerts to arrive before you feel the earthquake. Not
| sure why your iPhone didn't alert you while your android did as
| it should be from the same local data source.
|
| I really wish we had something like NERV but for SF, NERV works
| so well whenever I'm in Japan. It will literally show you a
| countdown of exactly when you'll feel it and it's very
| accurate, and you can see a livemap of monitoring stations
| reporting it in real time as the wave makes its way towards
| you.
| numpad0 wrote:
| LTE ETWS/PWS is mandatory feature, iPhones has the same thing.
| Maybe you've explicitly disabled it, considering (IIUC) US used
| it for AMBER alerts and had annoyed lots of people at some
| point.
|
| Generally an earthquake warnings are issued by someone always
| automatically correlating sensors everywhere, USGS and/or NOAA
| in case with US, and then cellular carriers broadcasting the
| alert through LTE feature. This does not work without
| participating local equivalent of USGS deploying a sensor
| network and running its computers wired to carriers.
|
| This feature is carrier agnostic, enabled by default, and
| mandatory on phones; it's specifically designed to deliver
| earthquake early warnings. It does not matter if it's Android,
| iOS, or something else altogether. Any phones, SIM locked or
| unlocked, with or without SIM, _should_ start blaring the alert
| so long it hears the signal.
|
| ref: https://en.wikipedia.org/wiki/Cell_Broadcast
| kccqzy wrote:
| I think OP is describing a different feature. It's not a
| carrier feature like Amber alerts but an OS feature. Google
| documents this feature here:
| https://crisisresponse.google/android-alerts/ I'm fairly
| certain this is due to some Android-specific code inside
| GMSCore. It has nothing to do with carriers.
|
| On iOS you have no such thing and you either rely on the
| carrier alert (there won't always be one) or install an
| earthquake alert app such as MyShake.
| Rebelgecko wrote:
| The wireless emergency alerts (like what you see for amber
| alerts) that go over cell towers have pretty high latency
| (IIRC on the order of a minute or two for the alert to
| disseminate). The native Android earthquake alerts are much
| faster
| numpad0 wrote:
| Carrier alerts is the fastest. Not only the whole process
| from detecting tremors to alerts take 30 seconds or so,
| there aren't other data sources than what those carriers
| use anyway, so there's just no way Google can be faster
| than carriers.
|
| PWS is also a broadcast, meaning the phones don't have to
| wait for cellular timeslots, so it's faster and bandwidth
| efficient in that regard too.
| Bratmon wrote:
| Android alerts got there way before carrier alerts today.
|
| Reality doesn't care what you think should be the
| fastest.
| Melatonic wrote:
| When I was on Android the integrated Google system was
| always much faster than anything else
| mgsouth wrote:
| For folks jumping on saying "that's not a carrier thing".
| _All_ comms are a carrier thing. Whether it 's ETWS, SMS, or
| IP, it's going through the carrier, they process it, and they
| do extensive traffic management. Carriers absolutely can and
| will inspect, proxy, aggregate, and do anything else that
| will tease out another few % of "free" capacity.
|
| [Edit:] All too real scenario: Carrier knows about particular
| IP addresses and ports used by alert service. Carrier makes
| provision for separate path for it. Carrier also tries to
| shave said provisioning to the bone, calculates a worst-case,
| and adds 5% capacity. Which doesn't get updated when that
| particular app gets a 6% boost in subscriptions. Back in the
| old days the traffic management folks would be on top if it,
| but that's all been outsourced...
| sib wrote:
| In this case, there is a separate service that Google
| developed for early warning.
|
| (Source, worked at Google in Android team.)
| numpad0 wrote:
| PWS is tower based broadcast. Everyone within range of a
| tower gets the alert. Data source is supposed to be local
| government weather authority, I think USGS and NOAA in US.
| Or the Meteorological Agency in Japan.
|
| You can do a location-based two way warning system and
| there are such services, but it's going to be laggy and
| won't scale to 100M+ simultaneous subscribers. One-way
| broadcast scales to the planet if wanted.
| eek2121 wrote:
| I use carrot weather with the critical alerts feature on the
| iPhone. It works great.
| Ancapistani wrote:
| Sigh.
|
| I've lost 15 minutes already because of your comment, and am
| on track to lose CARROT only knows how much more.
|
| Not only did you prompt me to download CARROT weather, I was
| foolish enough to set it on the "overkill" personality
| setting. I was amused by the banter until I found the
| "achievements" section. Then I saw that there was an
| achievement for downloading the Vision Pro app, so of course
| I had to get that one.
|
| I thought it was going to be difficult resisting enslaving
| myself to the will of CARROT on my iPad... woo boy. I wasn't
| prepared for the Neal Stephenson-flavored counterfeit GLaDOS
| that awaited me in visionOS.
| mgsouth wrote:
| It varies, a lot, and depends upon a lot of things. I'm not
| current on all the current details, but many moons ago was
| involved in push notification development.
|
| * Notification path. IoS at the time was pretty protective of
| the user's battery, and had specific services you had to use. I
| imagine there's special treatment now for emergency
| communications.
|
| * Phone state. How deeply asleep is it? Are there other
| background apps frequently contacting the mothership? Multiple
| apps can get their requests batched together, so as to minimize
| phone wake-ups. You can also benefit from greedy apps--VoIP
| apps, for example, might be allowed/figured out a hack to allow
| frequent check-ins, and the other apps might see a latency
| benefit.
|
| * Garbage carriers. Hopefully emergency alerts have a separate
| path, but I've noticed my provider (who shall remain nameless
| but is a three-letter acronym with an ampersand in the middle)
| sometimes delays SMS messages by tens of minutes. (TBF, in my
| case there might also be a phone problem [Android], but since
| nameless provider forced it on me when they went 4G-only
| they're still getting the blame.)
|
| In your case, my money would be on the carrier. Pushing a
| notification to all phones in an area can be taxing, and
| cheaping out on infrastructure is very much a thing.
|
| For docs, your best bet would be to go to the developer sites
| and pull up the "thou shalt..." rules, particularly regarding
| network activity, push notification, and permitted background
| activities. And yeah, Apple was much more dictatorial, for good
| reasons.
| dylan604 wrote:
| > a three-letter acronym with an ampersand in the middle
|
| wasn't the official name switched to no longer use that
| ampersand so it is just the three letters now (and for some
| time)?
| toast0 wrote:
| I believe they did announce that, and also claim that the
| letters no longer mean anything (which makes sense as
| telegraph is long dead, and the telephone network is
| primarily spam), however their website including investor
| relations has the ampersand everywhere, so maybe they
| backpedaled.
|
| Or maybe ampersand was dropped before SBC bought the
| remaining parts of the old business and reformed T-1000
| with the ampersand?
| dylan604 wrote:
| I thought that was when they dropped the ampersand when
| the biggest baby bell bought the remain baby bells to
| reform the mothership but couldn't use the ampersand
| since that was the entity that got broken up in the first
| place. You can't be too obvious about it and flaunt it in
| everyone's face. Subtlety is an art. And that art is
| clearly lost on the FTC
| whalesalad wrote:
| some great camera resources up and down the coast here -
| https://cameras.alertcalifornia.org/?pos=38.9615_-123.6676_8...
| andrewinardeer wrote:
| This is the biggest earthquake in California since when?
| joshuahedlund wrote:
| - 7.1 on 2019-07-05
|
| - 7.2 on 2010-04-04
|
| - 7.3 on 1992-06-28
|
| https://en.wikipedia.org/wiki/List_of_earthquakes_in_Califor...
| fckgw wrote:
| Looks like Ridgecrest 7.1 in 2019.
|
| https://en.wikipedia.org/wiki/2019_Ridgecrest_earthquakes
| some-guy wrote:
| Not how many other HNners live in Humboldt County, but that was
| certainly the most intense earthquake I've ever felt. Thankfully
| we are inland with modern(ish) construction.
| genter wrote:
| Really? I thought the one 2 years ago hit harder. This one was
| longer, though.
| some-guy wrote:
| To be fair I'm a recent transplant from the Bay Area.
| tonymet wrote:
| these systems were set up about 20 years ago after the Thailand
| tsunami. Have there been notable results from their application?
| dboreham wrote:
| Takes about 300 years to find out.
| Rebelgecko wrote:
| The western US was warned of tsunamis after the 2011 earthquake
| in Japan.
|
| They also released a warning before the 2009 tsunami in
| American Samoa but I'm not sure how effective it was due to the
| short timeframe and speed of disseminating the info
| latchkey wrote:
| https://nixle.us/FZ3E9
| cossatot wrote:
| Based on the location and focal mechanism of the earthquake (http
| s://earthquake.usgs.gov/earthquakes/eventpage/nc75095651...),
| this is a strike-slip earthquake on the plate boundary between
| the Pacific and Gorda/Juan de Fuca plates. Strike-slip
| earthquakes occur when two plates slide beside each other during
| an earthquake, usually along a steeply-dipping if not vertical
| fault. These kinds of earthquakes almost never produce damaging
| (or even really noticeable) tsunamis because there is no real
| displacement of sea water by seafloor movement, unlike a thrust
| or subduction zone earthquake.
|
| The USGS's automated systems calculate the location and focal
| mechanism/moment tensor pretty much instantly from the seismic
| network. The system should know that a significant tsunami is
| unlikely based on the parameters of the earthquake. On the one
| hand, it's good to be cautious, but on the other hand, a system
| designed to cry wolf is also self-undermining. Maybe they should
| have a tiered warning system?
| 0xffff2 wrote:
| Looking at https://tsunami.gov/, it seems like they do have a 4
| tier system, but they jumped straight to the highest tier in
| this case?
| throw83838 wrote:
| HN has good SnR generally, but I would default to trusting
| their automated system more than Random Internet Guy. Even if
| the warning gets canceled after measurements become
| available.
| cossatot wrote:
| I'm a Random Internet Guy who is a professional in the
| field (earthquake hazards, not tsunamis in particular).
| rootusrootus wrote:
| You definitely sound like it. But man, I've met some
| convincing liars online so I try to be cautious when
| someone makes claims and I have no proof that they are
| who they claim to be (especially when they didn't make
| that claim explicitly, and just sound very intelligent).
|
| It's a complication that will never happen, but sometimes
| I think it would be cool if HN had a way of
| authenticating experts and giving them flair. So many
| legit smart people here.
| jerlam wrote:
| It's a three-tier system, I was confused when I was looking
| at it. The fourth item is "threat" which you would think is
| higher than "warning", but "threat" is only used outside of
| the US.
| teaearlgraycold wrote:
| The system is training me to ignore it already. I'm in SF and
| we had a flash flood emergency alert. I never heard of or saw
| any floods. I could believe a street or two might have had a
| few inches of water at most. But honestly I'd bet against even
| that.
|
| And then there's this tsunami alert today.
| wbl wrote:
| SF topography means some places like the Mission and Dogpatch
| can have severe floods and the rest be fine.
| BurningFrog wrote:
| I really doubt an ocean Tsunami could have much of an
| impact in the Bay.
| OnlineGladiator wrote:
| I really doubt you know what you're talking about.
| s1artibartfast wrote:
| It is also unclear to me how someone is supposed to
| differentiate a real emergency from an "Extreme
| threat/danger" and what authority they should look to,
| besides their common sense.
|
| I guess people can go on twitter and read some random posts.
| taatof wrote:
| > I never heard of or saw any floods.
|
| There was a ton of flooding on flat roads and highways during
| the last week+ long storm session. I saw several lanes
| impassable on 101, and several spots in SF where a car could
| easily have gotten flooded.
|
| All the alerts I got were basically "please don't drive" and
| not "you're gonna die!", which I think is totally reasonable.
| crazygringo wrote:
| Flash floods depend on your elevation.
|
| I've gotten the warning and my street is perfectly fine...
| and then I look at social media and cars on the street are
| half-submerged just 20 blocks away.
|
| You might not even be aware of elevation differences when
| they're gradual.
| sib wrote:
| This is similar to the "severe weather alert" I just received
| on my phone when the temperature will range from 47' to 67' F
| (8' to 19' C) in Los Angeles today, December 5, with clear,
| sunny skies and no noticeable winds.
|
| Of course, when I tap on the notification and open the app, I
| see that it's actually driven by an air quality alert because
| the AQI will be 112 (which isn't even that high.)
|
| Come on guys - the dictionary defines weather as, "the state
| of the atmosphere with respect to heat or cold, wetness or
| dryness, calm or storm, clearness or cloudiness."
| bsder wrote:
| Flash flood alerts are one of the few that I don't get
| annoyed about seeing. A big rain up in the mountains can
| result in a huge chunk of water somewhere downstream a couple
| of _hours_ later. This significant displacement of time and
| space between cause and effect warrants caution and
| notification.
| rz2k wrote:
| Doesn't any earthquake, regardless of fault type increase the
| immediate risk of a submarine landslide?
|
| There are many steep canyons on the Pacific coast, and here is
| just one example of mass casualties from a tsunami resulting
| from a submarine landslide triggered by a strike-slip fault
| earthquake:
|
| Caltech, 2018[1]: "Contrary to Previous Belief, Strike-Slip
| Faults Can Generate Large Tsunamis"
|
| [1] https://www.caltech.edu/about/news/contrary-to-previous-
| beli...
| cossatot wrote:
| Yes, the probability of tsunamogenic landslides do increase
| during earthquakes, but it's still quite unlikely for an
| event of this magnitude tens of km from the continental
| slope; this is why a properly-calibrated tiered system would
| be better.
|
| The reason that the Palu event is so notable is precisely
| because it's uncommon. It's also a very different system: the
| causative fault is running along the axis of a shallow bay
| that is only a few km across, so even if the landslide did
| occur, rapid movement of the steep, shallow coastlines would
| surely have generated a smaller tsunami. It's a geographical
| and tectonic situation in which at least a minor tsunami is
| expected _a priori_ conditional upon an earthquake, so a
| warning system would account for that in principle. (In
| practice there isn 't time enough to mobilize because the
| tsunami hits while the ground is still shaking). The bay at
| Palu is like a somewhat larger Tomales bay--an earthquake
| right there is going to make some waves. Very different
| situation than one far off shore.
| gosub100 wrote:
| Those can even happen in bodies of fresh water. There's
| evidence of one at Lake Tahoe discovered by robot
| submersibles.
| LeoPanthera wrote:
| > The USGS's automated systems calculate the location and focal
| mechanism/moment tensor pretty much instantly from the seismic
| network.
|
| According to a USGS guy on the news just now, this isn't true.
| They know the location, and the magnitude, but the moment
| tensor takes time. Therefore any ocean earthquake 7.0 or above
| triggers an immediate tsunami warning.
| dataviz1000 wrote:
| I've been subscribing to tsunami warning system emails since
| the mid or late 2000s. They send the first email about the
| earthquake as a warning that something happened. Then after ,if
| a tsunami isn't detected they send an email saying that. If
| there is a tsunami they will send the first warning and as soon
| as sensors and satellites start to track the wave they will
| update at intervals with a table of expected arrival times and
| magnitude or height. So, yes, they send a warning that
| something happened, then they send information if there is a
| threat.
|
| Here is an example of the first message sent 9 minutes after
| 2011 Tohoku earthquake https://imgur.com/a/1mwAKqc.
| caseyf7 wrote:
| Also confusing when the SF Fire captain is on the radio telling
| people to evacuate to 100 ft above sea level right after a
| CalTech seismologist says it is unlikely to cause much of a
| tsunami due to being a strike-slip earthquake.
| jboy55 wrote:
| From
| https://www.tsunami.gov/events/PHEB/2024/12/05/24340001/2/WE...
|
| TSUNAMI THREAT FORECAST...UPDATED
| --------------------------------- * THERE IS NO
| LONGER A TSUNAMI THREAT FROM THIS EARTHQUAKE.
| psophis wrote:
| This message is for Hawaii.
|
| Edit:
|
| Now as of "1154 AM PST Thu Dec 5 2024" the warning is canceled:
|
| https://www.tsunami.gov/events/PAAQ/2024/12/05/so1aq0/3/WEAK...
| slwvx wrote:
| The "Pacific Tsunami Warning Center" is in Hawaii, which is
| why it is mentioned at the start of the message. Did you by
| chance just misread this? See the page below:
|
| https://www.tsunami.gov/?page=history
| neonate wrote:
| It's unfortunately hard to tell what regions that message is
| for, or whether it contradicts the other one saying the
| warning is still in effect: https://www.tsunami.gov/events/PA
| AQ/2024/12/05/so1aq0/2/WEAK....
|
| It looks like
| https://tsunami.gov/?p=PHEB/2024/12/05/24340001/2/WEPA40 is
| the 11:29 PST message saying there is _no_ tsunami warning
| for "Non-US/Canada Pacific".
|
| And it looks like
| https://tsunami.gov/?p=PAAQ/2024/12/05/so1aq0/2/WEAK51 is the
| 11:25 PST message saying there _is_ still a tsunami warning
| for "AK/BC/US West Coast".
|
| But it's not easy to tell what one's looking at if one
| doesn't already understand the system, and conditions of
| "extreme danger" (which is what my phone told me about half
| an hour ago) are not a good moment to figure these out.
|
| Edit: here we go:
| https://tsunami.gov/?p=PAAQ/2024/12/05/so1aq0/3/WEAK51 now
| says "No Tsunami Warning, Advisory, Watch, or Threat" for
| "AK/BC/US West Coast" as of 11:55 PST.
| colesantiago wrote:
| Why couldn't we predict this?
|
| If AGI is coming in 2025, why couldn't we see or predict this
| days ago?
|
| Edit: May I kindly ask why this is being downvoted? This is a
| valid question?
| bagels wrote:
| My machine learning model says that there is a 0.0047% chance
| of a 6.7 earthquake tomorrow.
| dekhn wrote:
| Why do you believe that AGI would affect earthquake
| predictions?
| colesantiago wrote:
| > earthquake predictions
|
| because we can't currently predict earthquakes?
|
| and if we can with AGI we would be saving lives?
| dekhn wrote:
| Let's unpack what you're saying.
|
| You seem to believe that AGI would be able to predict
| something that we have been actively researching for
| decades. I do not see how AGI would suddenly be able to
| solve a problem that smart people have already been working
| on, unless the AGI was also "superintelligent" in ways that
| contributed. AGI proper is merely artificial intelligence,
| not necessarily superintelligence.
|
| Second, I question that earthquake prediction would make a
| big difference in saving lives. In particular, earthquake
| prediction would come with a wide range of risks. It would
| have to balance true positives with false positives- after
| a few "OMG everybody leave SF" that didn't pan out, people
| would just tune out the tsunami warning. Also, telling
| everybody to leave a large urban area is prone to massive
| other problems such as increased accidents, disruption of
| delivery of food and emergency services, and increased
| overall stress. Likely, more people would die in response
| (increased road accidents) to your intervention, than were
| saved.
|
| It seems far more likely that investing effort into
| identifying actual risks (such as infrastructure that is
| likely to fail, or individuals living in places that are
| highly prone to flooding), and addressing those issues
| through systemic improvements would be a much more useful
| way to use the machine learning technology we have. And
| even that isn't necessary; we know what the problems are,
| we just don't invest in improving it.
| colesantiago wrote:
| lets pack this altogether.
|
| so you don't believe it would save lives?
|
| prevention is better than a cure and with AGI this would
| significantly a lot of people, not just SF.
|
| > smart people have already been working on,
|
| If they were so smart why haven't they found it yet? We
| now have weather prediction and protein folding now
| solved problems which were extremely difficult problems.
|
| I don't see how this doesn't apply to earthquake
| prediction, if it has to take AGI to solve it then so be
| it.
| dekhn wrote:
| I think it's unlikely having better earthquake prediction
| would save lives in an economically justifiable way.
|
| Neither weather prediction or protein folding are solved
| problems; that's the press misrepresenting the advances
| here.
| bagels wrote:
| They should really name these like storms/tornados: "warning"
| means there is actually a tsunami, "watch" means there might be a
| tsunami. The map showed the warning extending to >1000ft
| elevation. That is a little over the top.
| toast0 wrote:
| The ever present taco distinction.
|
| https://www.stevenscountywa.gov/pview.aspx?id=21417&catid=0
| bagels wrote:
| I had not seen it applied to tacos before, but it's the
| perfect metaphor.
| ahi wrote:
| The problem is that the proper response to a tornado is very
| different than that of a tsunami. In the case of a tornado,
| everyone moves to an interior room of a well built structure. A
| tornado warning means keep on an eye on the sky. In the case of
| a tsunami, thousands of people may need to evacuate many miles
| away. Expected landfall of any tsunami was something like 20
| minutes after this earthquake so they can't exactly wait until
| confirmation to get people moving.
| tj-teej wrote:
| I am riding the Caltrain south, we slowed to a snail's pace and
| they said it would take 2hr+ to get to Palo Alto (from SF).
|
| A bunch of people got off, and then the conductor comes back on
| the PA system to say the speed limitation had been limited and
| "we'll be going back to 79 MPH, hold on to your hats"
| mosdl wrote:
| First earthquake for the new electric trains probably, I can
| see why they would be cautious.
| toast0 wrote:
| A 7.0 earthquake nearby is a pretty good reason to slow down
| trains, regardless of propulsion.
|
| The easily found page about Caltrain's response to
| earthquakes [1] doesn't include magnitude 7, but also doesn't
| include earthquakes more than 100 miles from the tracks
| either. So I think a brief reduction in speed is reasonable
| for a large quake within the larger area and quickly ending
| the restriction as its confirmed the quake was outside the
| policy scope.
|
| [1] https://www.caltrain.com/rider-information/safety-
| security/e...
| nu2ycombinator wrote:
| you are happy because speed limit is lifted off or because of
| those people got off turned out to be wrong
| hash07e wrote:
| Ride the wave baby!
| jeffbee wrote:
| Canceled: BULLETIN Public Tsunami Message
| Number 3 NWS National Tsunami Warning Center Palmer AK
| 1154 AM PST Thu Dec 5 2024 ...THE TSUNAMI WARNING IS
| CANCELLED... * The Tsunami Warning is canceled for
| the coastal areas of California and Oregon
| joshlittle wrote:
| It has been cancelled.
| neonate wrote:
| https://tsunami.gov/?p=PAAQ/2024/12/05/so1aq0/3/WEAK51 as of a
| few minutes ago (11:55am PST) says there is no more warning for
| AK/BC/US West Coast, which would include northern California.
|
| This was confusing because the warning was called off earlier for
| a different region while still in effect for this one
| (https://news.ycombinator.com/item?id=42331931).
| alxjsn wrote:
| Final update:
| https://www.tsunami.gov/events/PAAQ/2024/12/05/so1aq0/3/WEAK...
|
| > * The Tsunami Warning is canceled for the coastal areas of
| California and Oregon
| wooten wrote:
| Two observations:
|
| 1) The blanket warning for areas that are clearly outside
| inundation zones drives a lot of confusion/fear. We can vastly
| improve our warning infra by utilizing better geo data to drive
| more effective alerts. For example, Tsunami inundation zone data
| is well known. Why not send only to phones currently in and maybe
| within 250m of those zones?
|
| 2) A lot of 'am I in a tsunami inundation zone?' sites were
| broken when I checked. them. Official government sites too. Of
| course that could be a function of traffic, but if so, it
| demonstrates a lack of resilience in their systems. We need
| better.
| sparky_z wrote:
| >Why not send only to phones currently in and maybe within 250m
| of those zones?
|
| There's often significant lag between the earthquake and the
| arrival time. You don't just want the people in the inundation
| zone to know, you also want everyone else to know to stay away.
|
| That's not just a theoretical edge case. If this had been a
| major tsunami your system would have killed me just now. I
| would have been outside of your suggested range and alone at
| the time of the alert, but was planning to walk my dog along
| the water front at noon, which was just around the projected
| arrival time.
| wooten wrote:
| ah yes excellent point.
| not_your_mentat wrote:
| I'm waiting for the big one to come and go before I'm willing to
| relocate to the west coast again. I was about to start looking
| for real estate and they they called the whole thing off.
| jrnichols wrote:
| Cancelled as of 1201 PST.
| alsetmusic wrote:
| I live in Oakland and the warning was cancelled about forty
| minutes ago. I did drive inland and put some large hills between
| me and the coast, however.
| unit149 wrote:
| Mass casualties stemming from a tsunami are predicated on the
| geographical significations of the region that it is hitting. One
| instance is the 2004 Indian Ocean tsunami and the havoc it
| wrought on the coast on much of the coastline of Thailand. There
| were coastal resorts that managed to avoid damage due to being
| situated in crescent shaped coves.
| jmward01 wrote:
| Of course, the elephant in the room here is how does this impact
| the risk of a Cascadia earthquake. This had to have just added a
| lot of stress to the southern segment.
| johnea wrote:
| Cancellation The tsunami Warning is canceled for the coastal
| areas of California and Oregon.
___________________________________________________________________
(page generated 2024-12-05 23:01 UTC)