WEBVTT

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Okay. It's 1 45.

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Thank you so much. Welcome back to our 1st after lunch session. I hope everybody got something delicious, and now we are on to something fun.

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I probably should not admit that the inspiration for this session was that when last year's kchatka earthquake happened.

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The earthquake. Scientists all looked at each other, and we're like wait. Is this an evacuation zone? Are we supposed to evacuate.

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Which is sub optimal. So to solve that problem. Today, we are going to talk about earthquake hazards in california.

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Well, you should evacuate when you should evacuate, and also about the kchaka earthquake.

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Both what a source was like and what its impacts were like in california, and to take us on this amazing trip. We have sean, paul lascell and stephanie ross, woo-hoo.

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你这个thanks，sir。

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So. Like. Ye thanks, sar So i'm stephanie ross. My co-fis solicitator, is sean pauliselle, and we're both with the usgs coastal marine science center.

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Our session is going to cover tsunamis from several angles, from average annualized losses in the us.

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To the event response process of the national tsunami warning center.

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Tsunami hazards in the san francisco bay area and its observations field instrental and satellite of the tsunami, generated by the july 2,025, kunchatka earthquake quake.

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So really happy to get this excellent broad group of speakers. I'll introduce the 1st 2 talks, and sean paul would introduce the others and kick off the discussion.

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So as for the other sessions, the talk videos will play back-to-back to back.

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With the live oral discussion after the last video, so feel free to enter questions in the chat during the talks.

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And to raise your hand in the oral discussion. After the last talk.

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Our 1st speaker is nate wood usgs research geographer who will be discussing a national assessment of population, exposure, evacuation, potential and average annualized losses in the us. To earthquake-generated tsunami threats.

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My name is nate wood. I'm supervisory of research geographer with the usgs, western geographic science center, and i'm here to present.

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On the national assessment of population, exposure, evacuation, potential and average annualizes in the united states. The earthquake generated tsunami threats. This was an effort done by my group working with great folks at fema.

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At, and the mit.

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So we're here to talk about characterizing us risk at the national level from earthquake-generated tsunamis.

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The main questions we had were, what kind of tsunamis threatened us. Coastal counities, how many people are in the us. Tsunami, hazard, zones.

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Will people have enough time to evacuate before tsunami waves arrived.

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Finally, how much could tsunamis cost to the united states.

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Again. This is smarizing 2. Journal articles plus a female report. So there's a lot here in 15 min.

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So how do we go about doing this? We pull together available state and territorial hazard zones.

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We also differentiated between local events and distant events, and i'll talk about that in a second.

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We use nationally, consistent residential data. We do acknowledge in the articles and in the report that there's obviously other folks that are in tsunami, hazard zones every day, employees.

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Visitors, tourists. Some are driving through a cruise ship tourists.

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But for this analysis of the national level we're currently we only currently focused on residential data.

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We then leveraged existing pedestrian evacuation modeling, or we did new, the evacuation modeling where there were gaps.

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物业assed fatalities for any place where there were residents in an area where travel time to safety was greater than wave，arrival，time。

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We worked with the national tsunami hazard mitigation program, all of the states and the territorial representatives.

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To estimate defendable recurrence intervals which would enable us to then do annualized losses, which was what schema's primary interest was for their analysis.

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And then we also use. Fema has a software to estimate building losses, and with that and the fatality assptions we calculated the average annualized losses.

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Not every tsunami source in the country was included. We included representatives, tsunamis, and talking with all the state and the territories.

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They were separated by distant events.

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他以an earthquake happened somewhere else。

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In the course of our several hours later waves do arrive, and impact coastal counities here in the us.

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So we use the mix of points which are deterministic scenarios, and then the lines represent the scenarios that all got wrapped into the california probabilistic efforts because they're currently the only state that has a probabilistic approach.

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To understanding all the various potential threats. And then for local events. That's where the earthquake happens right offshore, and then counities may have minutes to tens of minutes.

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Before they need to evacuate the safety. Again points where we had a scenarios, and then the red line was used in california to help build their cascade. Other probabilistic products.

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And in the end there were 102 earthquake-related tsunami, hazard zones, including 92 local scenarios, 8 distance scenarios and 2 probabilistic products.

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California has many more recurrence intervals. We just use the top 2.

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So. The 1st question is, how many residents might be in distance, you know i mean hazard zones.

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Tsunami hazard builds we got from states and territories.

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We estimated roughly, 3.3 million people are in these zones. Most of them are on the east coast.

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Either in scenarios associated with the puerto rican trench or the azores convergent zone, which is sitting off the coast of europe.

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That's the top graph. The bottom graph is showing the west coast and the pacific ocean.

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Here i. This area from hawaii to california. Those are all reflecting earthquakes that happen with the illusion. Alaskan subduction, zone.

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And in california. It's about a half a million residents in the.

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Average recurrence period of 2,000 422,475 years. And then, if you take a shorter time, span of 975 years, it's about 237,000.

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Known fatalities given the tsunami warning centers and the ordered evacuations and managed evacuations.

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Warning centers. And state and county and local law enforcement and emergency managers. So we asse there are no fatalities. What we don't asse that there might be a lot of challenges in evacuating that many people.

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So i'll quickly bring up 2 papers that we wrote specifically for california to discuss some of these issues, one being the potential for over-evacations.

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A paper in 2017, where we looked at. People that might be in the maxim tsunami zone used for evacuations which handles all scenarios around the pacific basin.

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Versus a scenario that only talked about the inundation related to an earthquake happening at chile.

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Showing up hours later, and a very quick take home is a place like alameda might have 45,000 people living in that mac zone.

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But only about 500 to 1,000 that would actually need to evacuate from direct impacts from a chilean related tsunami.

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Same thing for all the facilities that might be in this area of potential over over evacuation.

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There are many adult residential care, child daycare credential institutions, medical centers, schools, and even though the evacuation coordinator, in some cases.

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Might be an area that they would need to evacuate.

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The other challenge with a distance. Tsunami is that people may more likely than not will get in cars if they're told. They have several hours to evacuate.

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Obviously complicate things with traffic and potential congestion. So.

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One paper. We did back also in 2,017, was looking at bellbola island, where there was one bridge off to the mainland.

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And we with a different type of modeling, car-based evacuation modeling. We looked at it only takes about a half hour ish for folks to get off.

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But if they get their cars they could take up to 4 h. So again.

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啊。那段时间mixed in with people also walking or getting on bikes。

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啊。但obviously is，is a major challenge for anyone with a distant tsunami threat。

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All right back to our national assessment. We'll now look at local tsunamis.

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Here is the general nber of residents in local tsunami. Hazard zones, again curated from the state, has an assessment, state and territorial.

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In northern california. They'll never tell you in hble. That's roughly. 13,000 people living in something related to cascadia, subduction zone.

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61,000, and from also cascadia and oregon, 66,000 in washington. These are all just residents.

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的。These are not the same source。Parameters，the same assptions，so slightly different。

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But still give us a sense of how many people might be living in the cascadia, related zones.

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We then tried to figure out how many people may not have enough time to evacuate so pedestrian evacuation. Modeling was done to estimate clearance. Times.

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肯定会quickly。Show just。

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How this stuff is done, based on one of our very 1st papers, probably 15 years ago.

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Where you're taking elevation data imagery, land, cover, businesses, residents, and the hazard zone itself.

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This is ocean shores. Washington.

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Feeling, something called distance modeling will give us an idea of estimated travel times with a bunch of assptions built in.

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But that is what we did. Either certain states have their own modeling that we used, or we did, modeling of our own, to fill in the gaps.

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in general, about 245,000 residents in local tsunami zones, mostly in puerto rico and the pacific northwest.

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41 of the scenarios, where at least one resident does not have sufficient time.

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The highest are in puerto rico, around 21,000 from a puerto rican trench event.

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If you look at washington, oregon, and northern california.

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this graph here shows the nber of residents in a tsunami hazard zone on the x-axis.

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And the nber of residents that may not have are there in areas where travel times to safety are higher than wave arrival, time.

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And you can see here places like puerto rico.

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These are all. These are 2 related to oregon, and this is washington. So ye very high. Nbers of people living in hazard zones.

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When you look at the nber who actually may not have a sufficient time to come out.

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California, where there's 2 counties, is. Much lower in terms of oregon, washington, but the nber of folks that may not have sufficient time to get out, is actually in the same ballpark as oregon here in washington.

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Okay, if i pull out just specifically for the northwest.

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啊啊。

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10 min departure, delay from earthquake starts. Within 10 min people are actually moving the high ground, because the 1st 3 to 5 min.

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Very well could just be the the duration of the earthquake itself.

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And so, if we look at that 10 min departure, delay, you're looking at in california roughly, 13,000 that may not have time to make it out.

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That drops to 8,000, if people can leave the second, the earthquake were to stop the ground shaking so departure. Delay has a huge influence on the nber of people that may or may not have sufficient time to get out.

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If we then pivot to the annualized losses and the report and the articles get into the under the hood of how all this was done, but for the sake of time.

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We'll simply talk about the results in here. The take-home message is the average annualized losses potential.

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Not historic, but in terms of where people are living, and the recurrent intervals of these scenarios.

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And the probabilistic products, but a billion dollars on average average annualized losses.

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80% of that 794 million of average analyzed loss is actually related to the fatalities.

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And 209 million are related to the buildings. So the largest portion of savings for the country is actually in.

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saving lives, that is, there's a because of the local tsunami threat.

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And you can see california here roughly, 174 million annualized losses, 75% of that is related to fatalities.

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We get into the more of this at the report, but how we turn fatalities into dollars.

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Is, there is a rate? A nber used by fema and other agencies that put a price on a fatality or a certain nber of people injured in it. That nber changes every year due to inflation, but we used nbers, and that's in the report, and the the value that we used.

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To translate this into a financial loss. this one. I'll show also shows it annualized the fatalities on the x-axis, and then a loss ratio which is looking at that annualized fatality amount.

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Compared to per every 1,000 people exposed into a tsunami hazard zone.

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So i bring this up, because del norte and hboldt are actually come out in the top 10 counties for both.

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Some of the highest fatality losses, and the loss ratio meaning. There are other places that have a lot more folks in a tsunami hazard zone.

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But in these places that are circled for a higher ratio. That would be the red circles.

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There is a lot of folks high percentage of the people that are in the zone that may not have sufficient time to make it out. So dale norite is around. An average annual has lost so about 8 fatalities a year.

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If you look at recurrence intervals, hble this down to about 2, but their loss ratios are very, very similar, and so.

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We did this to help demonstrate these smaller coastal counties.

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Might not have the highest nbers of people in them, but the disproportionate impacts may be quite higher.

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we also are able to quantify the changes in the population loss, equivalence, that is, that.

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Economic expression of fatalities. by departure delay. So, for example, here in puerto rico.

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If everyone asses a 10 min departure delay, their average annualized fatalities are on 18 per year. If you got folks, leaving within 5 min that drops to 4.

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So that suggests outreach training, other interventions to get people moving faster out the door and up to higher ground.

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Has a significant impact to fatalities in puerto rico, california. It's evenly split, you know. It's at 10.

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In general drops to about 6, and then drops to about 3. If you make the departure delay smaller and smaller in washington.

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的meeting。Someone gets up and starts moving while the earthquake is still happening。

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There are still significant nbers of folks that may be in areas where travel times are just too high compared to wave arrival. Times.

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This is smarized. I mentioned earlier into 2 journal articles and one report. Here are the 2 articles.

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This upper one focuses on the just the population exposure, the evacuation modeling. So it's really just focusing on the people.

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That was published last year, and then a second paper got into the actual average annualized losses.

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And talking about the loss. Ratios, etc. The departure delay changes, and then this larger fema report is the larger, like 300. Page.

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They are a little far greater, which gets into a much more details about what scenarios were used, what methods were used to estimate the recurrence intervals, because that did vary across the country. There was not one consistent way to look at recurrence intervals.

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And then, finally, as part of this.

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那样，数码population，exposure paper that i led。

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But we also have a data release that you can download for free. And it's you can open it in, excel, and you can then query.

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filter things by here. I just have a screen grab of.

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California, dell, norton, hboldt.

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的counity levels，the scenario。These are all the twenty，four，seventy，five。These are all local。

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How many residents are in the zone, and then who might have insufficient time? We'll jp over here with a 10 min delay.

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5 min delay if they got up right out of the gate and left, even while the ground is still shaking.

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So that is all. That's the end of the the presentation. If you'd like to reach out to me, and and would@usgs.gov.

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Great to hear from you. If you have any questions i can send along the articles and answer any questions you might have.

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So thanks for your time.

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Thanks, nate, i've always learned so much from your talks.

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And thanks also for the great set of resources you put in the chat.

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Our next speaker is no's smer, olandore from the national tsunami warning center. Smer is going to be offering a look inside no tsunami, event, response.

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Hi. This is smer olandorf at the us. National tsunami warning center.

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And i'll be giving you a brief overview of us. Tsunami response.

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So you know, i'm using tsunami. Threats are a lot more frequent than a lot of people realize.

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You can see here that 2025 was a pretty busy year for us.

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Like earthquakes. Tsunami's occurred at a wide range of sizes and skills and generation types too.

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One of our challenges is fighting the perception of false alarms for real threats that don't end up leading to damaging tsunamis.

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But every one of these occasions is a chance to refresh education and practice response.

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To briefly orient you on the noa tsunami program.

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的includes both tsunami warning centers。

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As long as the operational learning infrastructure. However, we have supporting components and other noa line offices the focus more exclusively on things like research.

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Archives and observations. At full staffing. The national weather service. Part of the tsunami program has about 40 people total between both tsunami warning centers.

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And the internationals tsunami information center. We also have a few people at the national centers who are helping with management functions.

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But this is a pretty small group overall. And we're responsible for keeping at least 2 duty scientists on watch, 24, 7.

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With capacity to obviously surge in the case of a tsunami event.

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The 2 sonoma warning centers are the national tsunami, warning center in alaska and the pacific tsunami warning center on ford island in hawaii.

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Each tsunami warning center is monitoring globally for any potential potential tsunami threats to the areas that it covers.

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For ntwc. That's the coast of continental, us. And canada, both pacific and atlantic.

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And for a. Ptwc. That's the state of hawaii.

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The US. Territories in the pacific and caribbean. And they also have an international advisory responsibility to issue information for countries that may or may not have their own tsunami warning systems.

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Mostly now music caused by big earthquakes, but while historically specialized to respond to earthquake, generated tsunamis.

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的。

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We signed 2022, the hungatanga. Eruption tsunami, which was a pretty big surprise, for most of us.

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And within the last 5 years, especially landslide generated tsunamias have become a pretty big conversation topic, especially in alaska.

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The twcs are in the process of better generalizing our systems to more seamlessly respond to all possible tsunamis.

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And tsunami scientist is really just interdisciplinary, which keeps it fun.

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It's monitor for tsunamis. The twcs maintained in jests of about a thousand different seismic stations.

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And about 1,000 different water level stations, globally. Seismic stations, help us, detect and characterize earthquakes.

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Ocean bottom pressure sensors in the deep ocean help us detect.

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Tsunamis and forecasts. With that information before we can see impacts along the coast.

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And coastal water levels help us see real impacts.

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And also inform cancellations and changes to other org levels.

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Our internal goal. Timeframe for issuing domestic tsunami alerts is 5 min.

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Since local tsunamias can create impacts along the coast in under 15 min.

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Our operations are optimized for speed throughout. And we're always balancing, trying to be as fast as possible and using automation.

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With being able to be flexible and customize alerts, particularly for any sort of situation.

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As we analyze earthquakes, the 2 tsunami warning centers are coordinating with each other.

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And for the initial bulletin. The location of the quake determines which twc is going to be authoritative.

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With other twc following. And issuing their information with the same earthquake parameters.

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After issuing its procedure for us to also contact nieisc.

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And see what preliminary information they're getting about. The earthquake.

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In addition to coordinating with us, andtwc. Ptwtwc is also coordinating with japan for earthquakes in their area.

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And also with the south china sea tsunami advisory center.

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Later, as the authoritative nec parameters are issued for an event.

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Both twc is adopt those going forward to help minimise confusion.

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Our earthquake information is always considered preliminary. And ye i see, is the authority.

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Once we have earthquake information, we have to associate that with tsunami alerts. If any.

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Our initials, tsunami alerts are always based on pre-established procedures.

00:21:45.000 --> 00:21:49.000
And those depend on the earthquake, magnitude, depth, and location.

00:21:49.000 --> 00:21:56.000
Our procedures are informed by a suites of model runs, as well as historical earthquake, and tsunami event statistics.

00:21:56.000 --> 00:22:03.000
We're always airing on the conservative side with our initial bulletins, though, because the impacts can be great. If we don't.

00:22:03.000 --> 00:22:09.000
it's important to remember that we almost never have confirmation of a tsunami by the time of the 1st message is sent.

00:22:09.000 --> 00:22:16.000
Due to the spacing of sensors and the amount of time it takes for tsunami waves to travel.

00:22:16.000 --> 00:22:25.000
Later on, in an event we might end up adjusting lower levels, based on adjustments to the magnitude that could put us into a different procedural bin.

00:22:25.000 --> 00:22:29.000
As well as obviously a sea-level measurements as we start getting them.

00:22:29.000 --> 00:22:38.000
And we can use those to validate forecasts and monitor. What's actually going on on the coasts and make sure we change accordingly.

00:22:38.000 --> 00:22:43.000
Most coon type of message issued by the twcs is a tsunami information statement.

00:22:43.000 --> 00:22:48.000
Which is, for where there's no threats or very low probability of a tsunami threat.

00:22:48.000 --> 00:22:53.000
We issue those when we have either a domestic coastal earthquake that's big enough for people to have.

00:22:53.000 --> 00:23:01.000
To have felt, or for a larger earthquake farther away. But that, we know isn't going to impact our coastlines.

00:23:01.000 --> 00:23:09.000
We also have a tsunami watch. That's possible. A tsunami watch is when we have a big enough earthquake that it could generate impacts.

00:23:09.000 --> 00:23:15.000
But as far enough away from our coastlines that we've got time to gather more information and forecast.

00:23:15.000 --> 00:23:21.000
To better determine the level of threat. Tsunami advisory and tsunami warnings.

00:23:21.000 --> 00:23:26.000
们dangerous waves。

00:23:26.000 --> 00:23:32.000
For those we do have some water levels associated with them, and those are one to 3 feet. First, st you know, i mean advisory.

00:23:32.000 --> 00:23:38.000
And 3 feeder, but for tsunami warning. If you've been to your coast that doesn't sound like much.

00:23:38.000 --> 00:23:45.000
But remember that tsunami waves are very long, and coming in very fast, so even a couple of feet of water.

00:23:45.000 --> 00:23:51.000
And is capable of moving cars and creating damage in ports and arenas.

00:23:51.000 --> 00:24:00.000
A tsunami advisory means that the danger is primarily going to be for the nearest coastal areas. So beaches, harbors, marinas.

00:24:00.000 --> 00:24:10.000
Tsunami warning is when we do expect more serious impacts and expect people to need to be able to evacuate.

00:24:10.000 --> 00:24:20.000
Those water level thresholds are based on the extent of damage, though that have been observed at past tsunami events and various tsunami implicitudes.

00:24:20.000 --> 00:24:25.000
And tw. C. Warns by applying those different alert levels to coastal sections.

00:24:25.000 --> 00:24:37.000
Between locations that we call breakpoints. This has the advantage of being a little bit simpler for people to understand. You don't have to zoom in on a map to try to figure out what alert level you're in.

00:24:37.000 --> 00:24:44.000
it's it's pretty easy to keep track of. However, obviously, the precision. Isn't that great.

00:24:44.000 --> 00:24:52.000
However, based on the density of coastal observations and the uncertainties in forecasting.

00:24:52.000 --> 00:24:58.000
This is about as we good as we can do. I'm guessing what alert levels people need to be in, anyway.

00:24:58.000 --> 00:25:03.000
So it's it's a pretty good system for now.

00:25:03.000 --> 00:25:11.000
Once we issue a tsunami. Alert dissemination happens pretty rapidly to a nber of systems at once, with one click by duty, scientist.

00:25:11.000 --> 00:25:17.000
Afterward we're busy making notification calls and also activating our internal staff. Recall.

00:25:17.000 --> 00:25:26.000
Some important things to point out here are that only a tsunami warning goes to weia. An advisory does not, despite the fact that it can be a very dangerous.

00:25:26.000 --> 00:25:35.000
Situation for people directly at the coast. Also are sending to, and nws gateway.

00:25:35.000 --> 00:25:45.000
Is a way that the weather forecast offices can receive the message, and as the weather forecast offices, so that are responsible for transmitting that message to no weather radio.

00:25:45.000 --> 00:25:50.000
And to the ea system.

00:25:50.000 --> 00:25:58.000
During a tsunami event. One of our iediate priorities is to make sure that we're counicating our evolving understanding of the hazard.

00:25:58.000 --> 00:26:03.000
With our core partners. Those core partners are decision makers.

00:26:03.000 --> 00:26:10.000
Responsible for alerting and directly working with counities and other constituents.

00:26:10.000 --> 00:26:16.000
Our partners become extensions of us during a tsunami event, translating and amplifying our information.

00:26:16.000 --> 00:26:20.000
For their counities. All tsunami events are different.

00:26:20.000 --> 00:26:27.000
And also nomi events are unusual, so the direct counication is really important.

00:26:27.000 --> 00:26:33.000
Some of the ways we handle this counication. Is through hourly video conference calls.

00:26:33.000 --> 00:26:37.000
We start those within the 1st hour, and we keep them going. Throughout the duration of an event.

00:26:37.000 --> 00:26:48.000
And through national weather service, chat with our partners. That's on the slack platform, and enables us to counicate in real time in between those conference calls.

00:26:48.000 --> 00:26:54.000
We also, of course, do individual phone calls with partners as needed.

00:26:54.000 --> 00:26:59.000
So in the 1st part of a tsunami event, we're detecting a hazard. We're analyzing it.

00:26:59.000 --> 00:27:05.000
We're looking at pre-computed forecasts to get an idea of the range of possibilities that we're in for.

00:27:05.000 --> 00:27:13.000
And we're starting that counication cadence with our partners, preparing to send, follow up messages, as we need to.

00:27:13.000 --> 00:27:21.000
Later on we start getting ocean observations from the darts in the deep ocean, and then eventually the coastal water, level sensors.

00:27:21.000 --> 00:27:27.000
Those help us come up with better forecasts and better match our alert levels to the impacts.

00:27:27.000 --> 00:27:35.000
Throughout all of this our confidence in the forecast is increasing, and our alerts better match the hazard.

00:27:35.000 --> 00:27:44.000
We use multiple different forecast models in-house and for right now all of these are deterministic. But in our next generation of systems. We're moving towards using ensembles.

00:27:44.000 --> 00:27:55.000
Moving towards probabilistic forecasts. As we get forecasts as soon as they're validated by dart observations and other water, level observations.

00:27:55.000 --> 00:28:04.000
We incorporate those into messages and release the information to our website, so that they can be used by coastal emergency managers.

00:28:04.000 --> 00:28:10.000
Depending on the source location, though, and which darts may or may not be operational at the time.

00:28:10.000 --> 00:28:14.000
It's often one to 2 h from the earthquake origin, time.

00:28:14.000 --> 00:28:21.000
Until there's a verified tsunami forecast. That accounts for both the tsunami travel time.

00:28:21.000 --> 00:28:26.000
As well as the very long wavelengths of tsunamis.

00:28:26.000 --> 00:28:32.000
Mr. Army waves reach the coast. We're using coastal tide gauges to verify forecasts and alert levels.

00:28:32.000 --> 00:28:37.000
And trying to adjust those as needed, and cancel an appropriate.

00:28:37.000 --> 00:28:41.000
But there's a bit of an art to this. It's not at all cut and dry.

00:28:41.000 --> 00:28:49.000
Our rule of thb is to downgrade or cancel alerts. Once waves have remained below a particular threshold for at least 3 h.

00:28:49.000 --> 00:28:57.000
And that's generally because tsunami waves tend to. Bounce around in some of those coastal areas. For a while.

00:28:57.000 --> 00:29:02.000
And very UN amplitude a bit. So 3 h tends to be a pretty good.

00:29:02.000 --> 00:29:06.000
Span of time for us to see what they're. They're going to continue to do.

00:29:06.000 --> 00:29:12.000
But throughout this part of the event this is a good opportunity for collaborative decision, making.

00:29:12.000 --> 00:29:23.000
So during those hourly conference calls and on slack, we've been able to work with coastal ems to make the best decisions for their counities.

00:29:23.000 --> 00:29:32.000
For example, in the kemchaka event we were able to use specialized messaging to keep the barrier out of a tsunami warning.

00:29:32.000 --> 00:29:39.000
We were also able to work with the ems in northern california on the timing of work, cancellation, and crescent city.

00:29:39.000 --> 00:29:44.000
To make sure that we wouldn't be doing more harm than good.

00:29:44.000 --> 00:29:55.000
Mr. Ber program is in the middle of the time of great change right now, and we've finally been resourced to make a lot of the long-standing changes that we've known have been necessary.

00:29:55.000 --> 00:30:02.000
For example, that we are building a new version of tsunami gov. That'll be a lot more modern and user friendly.

00:30:02.000 --> 00:30:05.000
So people will be able to go there and easily understand.

00:30:05.000 --> 00:30:09.000
What their level of hazard is during a tsunami event.

00:30:09.000 --> 00:30:15.000
We're also making sure that the 2 tsunami warning centers are more aligned in the way we're that we're doing things.

00:30:15.000 --> 00:30:26.000
And better able to be responsive to our core partner's needs. So we're doing that through modernizing our analytic systems and our messaging systems.

00:30:26.000 --> 00:30:33.000
To once they'll be coon for both tsunami warning centers, and more able to implement new technologies.

00:30:33.000 --> 00:30:46.000
Requests as we get those. Hopefully, all resulting in more consistent operations, better backup and service coordination, and a coon operating picture during a tsunami event.

00:30:46.000 --> 00:30:54.000
I love helping people learn about what we do and hear new ideas, and i could easily go on for hours about all of these topics.

00:30:54.000 --> 00:31:00.000
So please feel free to contact me or one of my colleagues. If there's something that we can help you with, or that you want to follow up on.

00:31:00.000 --> 00:31:05.000
As in my role as the science and operations officer at ntwc.

00:31:05.000 --> 00:31:10.000
My specialties are data analysis science and staff training.

00:31:10.000 --> 00:31:15.000
If you have an alerting concern, you'll probably want to talk to ours. Tsunami, warning coordinator.

00:31:15.000 --> 00:31:20.000
And i know we've got earthquake early warning folks in the audience. So he's your go-to for that.

00:31:20.000 --> 00:31:23.000
We've got ptwc. And itic staff on here, too.

00:31:23.000 --> 00:31:32.000
But we're happy to hear your ideas and thank you for listening.

00:31:32.000 --> 00:31:42.000
Great thanks smer Super interesting talk, and i think we'll continue to talk a little bit more about the khanchakis tsunami. So we have a series of.

00:31:42.000 --> 00:31:46.000
3 talks all the way from space down to the ground.

00:31:46.000 --> 00:31:52.000
looking at observations, fascinating observations, about the 2,025 khan shocker earthquake.

00:31:52.000 --> 00:32:04.000
A tsunami, so we'll start with anger. Ruiz angolo in iceland at what's that? 1017 PMA. Local time?

00:32:04.000 --> 00:32:11.000
Hello, everyone. Thank you very much for inviting. Me to this to this event. I'm very happy to share with you.

00:32:11.000 --> 00:32:18.000
The work we've been doing. About the fantastic observations from the swath.

00:32:18.000 --> 00:32:25.000
Satellite over the toronometerinary in kansatka. Magnitude 8.8 event.

00:32:25.000 --> 00:32:29.000
Past year, and i would like to acknowledge my.

00:32:29.000 --> 00:32:34.000
Authors. I've been working a lot. With diego on.

00:32:34.000 --> 00:32:39.000
Tsunamis, and. I learned a lot about swat.

00:32:39.000 --> 00:32:46.000
Charlie and the ones that helped us to identify that the model we were using.

00:32:46.000 --> 00:32:50.000
Was very suitable for. For the for the swallop passes.

00:32:50.000 --> 00:32:56.000
Was already in, and francesco. And balla has helped us a lot to figure out the.

00:32:56.000 --> 00:32:59.000
Sort of part of the seismic that we will.

00:32:59.000 --> 00:33:02.000
Talking about in this paper.

00:33:02.000 --> 00:33:05.000
的。

00:33:05.000 --> 00:33:11.000
Introduction i would like to define or like, show what is sought for those that do not know. It.

00:33:11.000 --> 00:33:17.000
So what is a relatively new satellite. So these new satellite. It's.

00:33:17.000 --> 00:33:21.000
Been, stands for the surface, water and ocean topography.

00:33:21.000 --> 00:33:25.000
Join collaboration of space agencies between the us. France.

00:33:25.000 --> 00:33:31.000
Canada and the united kingdom. It was lunched in december 2022.

00:33:31.000 --> 00:33:35.000
For us is our new toy. As an oceanographer. We are.

00:33:35.000 --> 00:33:39.000
I'm really enjoying looking at the data and the new resolution that we have.

00:33:39.000 --> 00:33:48.000
Fantastic processes that we can observe. So swat is is a little bit like a cartoon house. Swat looks like.

00:33:48.000 --> 00:33:52.000
So he has an ultimatre like regular satellites that do.

00:33:52.000 --> 00:33:58.000
Ocean, elementary, or like ultimate, in the ocean. They do have an ultimate. It's a.

00:33:58.000 --> 00:34:01.000
But it's a single beam you want to call it.

00:34:01.000 --> 00:34:06.000
But what makes? What different is that. Next to each other, next to the next. To this.

00:34:06.000 --> 00:34:08.000
Now the that is called the ultimatter path.

00:34:08.000 --> 00:34:12.000
然后two swatts and those swaths like。

00:34:12.000 --> 00:34:19.000
2 different footprints that we have for the. For the surface of the ocean. You could think about it as the.

00:34:19.000 --> 00:34:23.000
As a boat that is measuring, but imagery in the ocean.

00:34:23.000 --> 00:34:27.000
If you would have had a single beam, you will only get the ultimate part.

00:34:27.000 --> 00:34:31.000
But if you have a multi beam, you can get actually footprints or the swats next to each other.

00:34:31.000 --> 00:34:37.000
所以stands of about a hundred and fifty kilometers in twenty seconds。It's very fast。

00:34:37.000 --> 00:34:47.000
meaning that in 20 seconds we can get Near real-time snapshot of an area that is, 120 kilometers by 100.

00:34:47.000 --> 00:34:52.000
Currently is what does something that is called repeated orbits.

00:34:52.000 --> 00:35:01.000
They happen every 21 days. And how close those orbits are next to each other. Well, it depends sort of on the latitude.

00:35:01.000 --> 00:35:05.000
Time that varies between. Between the orbits. Nevertheless, like.

00:35:05.000 --> 00:35:09.000
In 21 days he would return to the same location.

00:35:09.000 --> 00:35:15.000
This also gives us. Hint, and how lucky we were on this observation.

00:35:15.000 --> 00:35:20.000
Some examples that i want to highlight. Highlight, this in waves.

00:35:20.000 --> 00:35:26.000
In oceanography. We like internal waves a lot, and there's a particular region in the ocean in the indian ocean that.

00:35:26.000 --> 00:35:29.000
You know it's the largest internal waves on earth.

00:35:29.000 --> 00:35:33.000
And in this picture that we have here we can see.

00:35:33.000 --> 00:35:38.000
Big squares. Here those are the. Greeted products that we used to have.

00:35:38.000 --> 00:35:43.000
For ultimately, long ago, in these quarters, you cannot really see any of the internet waves.

00:35:43.000 --> 00:35:49.000
There's also generated as a. As an average, for many passes.

00:35:49.000 --> 00:35:54.000
说gets these two bands，and in these two bands we can see they。

00:35:54.000 --> 00:35:57.000
Internal waves that have been generated.

00:35:57.000 --> 00:36:00.000
Some of these like red stripes that we have here.

00:36:00.000 --> 00:36:02.000
你是不是。

00:36:02.000 --> 00:36:10.000
For example, resolution for the swot. This product. But if we go to the very, very high resolution of swat.

00:36:10.000 --> 00:36:17.000
Which is almost the raw data. We can. We teach about 250 meters? We can see actually the swell.

00:36:17.000 --> 00:36:24.000
对swell that is within this internal website。Basically，the capillary website。

00:36:24.000 --> 00:36:29.000
A lot of example of how they look like this could be like 2 passes with the ultimate.

00:36:29.000 --> 00:36:37.000
Area, 25. Whereas with swot, we can see all these details that are happening on this rather.

00:36:37.000 --> 00:36:41.000
就是说给你钱就是的。

00:36:41.000 --> 00:36:46.000
But about tsunamis and satellites, or remote sensing observatories.

00:36:46.000 --> 00:36:52.000
Is not the 1st one, so i. To my knowledge, the 1st one is the 2,004.

00:36:52.000 --> 00:36:56.000
Satra aircraft, very, very large earthquake.

00:36:56.000 --> 00:37:01.000
们。

00:37:01.000 --> 00:37:07.000
Of serving the tsunami. Here we have a picture of nerical simulation that is published in this paper.

00:37:07.000 --> 00:37:12.000
And same simulation, but around the same time that there was jason.

00:37:12.000 --> 00:37:17.000
So jason truck is in. Really serious, and like we have the sea surface hide. That's the.

00:37:17.000 --> 00:37:21.000
A function of the latitude.

00:37:21.000 --> 00:37:24.000
然后就出错了。Spatial radial。

00:37:24.000 --> 00:37:29.000
Sense here, and we can see that this the satellites they were able to.

00:37:29.000 --> 00:37:34.000
Sort of, or much more or less, the nerical model that is here.

00:37:34.000 --> 00:37:37.000
And then.

00:37:37.000 --> 00:37:44.000
我们。们。

00:37:44.000 --> 00:37:50.000
Is very close to when swat was released. And then, after swat was released in.

00:37:50.000 --> 00:37:58.000
May 2023. There was the first.st Words, when i may be recorded by swatz.

00:37:58.000 --> 00:38:03.000
The loyalty islands, and we can see here in this panel day.

00:38:03.000 --> 00:38:07.000
American model for this paper. That that is under review.

00:38:07.000 --> 00:38:13.000
And this is the main wave that was generated by the model.

00:38:13.000 --> 00:38:16.000
Where the swat track will have been able to see it.

00:38:16.000 --> 00:38:19.000
And here we are. They are overly in the the swart track.

00:38:19.000 --> 00:38:21.000
是说track on。

00:38:21.000 --> 00:38:27.000
Matching the colors and the timing of the swot with the model are relatively good.

00:38:27.000 --> 00:38:33.000
Maxim amplitude. But the 1st striking thing is all these complex.

00:38:33.000 --> 00:38:37.000
Structure that is bind the. Bind the way the main way.

00:38:37.000 --> 00:38:43.000
This structure is not reproduced by the models. And we could see here in this sort of.

00:38:43.000 --> 00:38:46.000
This is distance along the track.

00:38:46.000 --> 00:38:54.000
们，that's what has。很。This is sort of the shape of the wave that it will。

00:38:54.000 --> 00:39:00.000
们。所谓的毛泽东has the first wave。

00:39:00.000 --> 00:39:03.000
里非我们。

00:39:03.000 --> 00:39:06.000
All the waves that are trailing bind the rainbow.

00:39:06.000 --> 00:39:08.000
This is one of the main striking ones, another.

00:39:08.000 --> 00:39:10.000
Example, on tsunami's width.

00:39:10.000 --> 00:39:13.000
说this one，the dixon filled。

00:39:13.000 --> 00:39:18.000
Sort of landslide. He was not a non airway. Trigger tunami.

00:39:18.000 --> 00:39:21.000
我generated，but a massive landslide。

00:39:21.000 --> 00:39:24.000
And it resonated for about 9 days.

00:39:24.000 --> 00:39:28.000
未定的landslide。

00:39:28.000 --> 00:39:33.000
的，为什么。所以as a stationary wave，or like a。

00:39:33.000 --> 00:39:36.000
还的需要。

00:39:36.000 --> 00:39:39.000
But i was 90 days, and this wave, or the.

00:39:39.000 --> 00:39:42.000
了。

00:39:42.000 --> 00:39:48.000
Generated, or triggered. Some sites, meat, waves that appropriate all around the earth.

00:39:48.000 --> 00:39:53.000
For about 3 days. So this is another remarkable observation from swat.

00:39:53.000 --> 00:40:02.000
These actually uses the superhigh resolution, pixel size. Just to estimate, just to show more or less.

00:40:02.000 --> 00:40:07.000
The high state and the low state. That was existing that was within the.

00:40:07.000 --> 00:40:10.000
我们。

00:40:10.000 --> 00:40:16.000
So now this is our event. Updated captain sort of close to midnight. Dmt.

00:40:16.000 --> 00:40:20.000
We had like the task that. And start like simulating that one.

00:40:20.000 --> 00:40:23.000
所谓的task is just a。

00:40:23.000 --> 00:40:28.000
Curiosity task. We use usgs as our 1st source.

00:40:28.000 --> 00:40:31.000
就行的，还。

00:40:31.000 --> 00:40:35.000
Using a slap model, which was the geometry that was provided at that time.

00:40:35.000 --> 00:40:39.000
And we use geograph for the simulation. And.

00:40:39.000 --> 00:40:46.000
Then, after after the simulation was actually. Release, or published it in.

00:40:46.000 --> 00:40:55.000
In blue sky. This was. About this event. At the same time they there was a there was a sword pass.

00:40:55.000 --> 00:40:59.000
Like. I was not really aware that this road was passing up.

00:40:59.000 --> 00:41:01.000
Particular time. I was not really.

00:41:01.000 --> 00:41:08.000
的passed by here。

00:41:08.000 --> 00:41:11.000
Just about 40 min after the after the earthquake.

00:41:11.000 --> 00:41:13.000
some.

00:41:13.000 --> 00:41:15.000
们colleagues，now。

00:41:15.000 --> 00:41:21.000
In france. They looked at the at the traatic propagation that i was publishing in blueskite.

00:41:21.000 --> 00:41:25.000
They took a snapshot, and they sort of match the.

00:41:25.000 --> 00:41:29.000
Timestamp, for that, with the short paths and the.

00:41:29.000 --> 00:41:31.000
康，在民们。

00:41:31.000 --> 00:41:34.000
Me that it was really it was matching quite well.

00:41:34.000 --> 00:41:38.000
们。

00:41:38.000 --> 00:41:41.000
就是的。

00:41:41.000 --> 00:41:46.000
Actually does match quite well. So we started collaborating with them.

00:41:46.000 --> 00:41:55.000
很。跟charles of falls satellite elementary data in france。

00:41:55.000 --> 00:41:58.000
And he also made it to the newsletter.

00:41:58.000 --> 00:42:00.000
We were able to match the time quite well.

00:42:00.000 --> 00:42:08.000
I'm a very good. 1st sort of validation of the.

00:42:08.000 --> 00:42:16.000
And we started, then working on a. Well, no real paper for the real paper. Now. We wanted to.

00:42:16.000 --> 00:42:28.000
把violent stations，and we found the first。叫我什么？So they are like three stations that we were doing comparison this one，that is，forty，one，nine。

00:42:28.000 --> 00:42:32.000
41,5.

00:42:32.000 --> 00:42:36.000
We found that there was a. Late arrival, for example.

00:42:36.000 --> 00:42:44.000
The one that is, 4, 1, 9. The lines that we have here. The dark one is the dark observations.

00:42:44.000 --> 00:42:48.000
The us. Yes, sleep model. Now this is a sleep model. This noses love model.

00:42:48.000 --> 00:42:56.000
Shows that there was a. The red bavior here, and we can see that there is a late arrival for about 10 min.

00:42:56.000 --> 00:42:59.000
And the other ones. The other station. That is the.

00:42:59.000 --> 00:43:02.000
就是刚才sixteen。That is here in the middle。

00:43:02.000 --> 00:43:07.000
That one did not show any delay or. Was not late, not early arrival.

00:43:07.000 --> 00:43:13.000
However, you would match the usgs. But the other one that is below the.

00:43:13.000 --> 00:43:19.000
In the southwest. The 419 that one actually arrived early.

00:43:19.000 --> 00:43:24.000
了。

00:43:24.000 --> 00:43:33.000
Diego went on the task. Well the magnitude of the arrivals, the late arrivals, and earliest in the order of 10 min, which is a lot.

00:43:33.000 --> 00:43:39.000
And then diego sort of. They want to solve, for to.

00:43:39.000 --> 00:43:43.000
Fix the problem. So he use his iersion. So we are gonna.

00:43:43.000 --> 00:43:49.000
我们。所以的。

00:43:49.000 --> 00:43:54.000
You can see that the red patches further to the northeast.

00:43:54.000 --> 00:43:59.000
The red bunch of maxim sleep. And that one is the one that shows this.

00:43:59.000 --> 00:44:01.000
Late arrival, early arrival on the other.

00:44:01.000 --> 00:44:07.000
就是要then，if we were using only sleep，distribution from darting versions。

00:44:07.000 --> 00:44:11.000
Then we would lose it. It was losing a lot of the a lot of the.

00:44:11.000 --> 00:44:14.000
Material. That was the negative sort of sleep that was.

00:44:14.000 --> 00:44:17.000
Because he was only using that.

00:44:17.000 --> 00:44:23.000
but the patch was moving further south. Then my hybrid version that diego created.

00:44:23.000 --> 00:44:26.000
的，对于的。

00:44:26.000 --> 00:44:30.000
He generated this new line that we have here. The green line.

00:44:30.000 --> 00:44:36.000
And this green line has a really good match. This is the tsunami model using that blended model.

00:44:36.000 --> 00:44:40.000
Did not have any late arrival anymore. This one did not change.

00:44:40.000 --> 00:44:43.000
Lost a little bit of the amplitude, but i was about it.

00:44:43.000 --> 00:44:46.000
And the last one was not anymore out of faith. So.

00:44:46.000 --> 00:44:51.000
It was fixed. We were very happy. But we still had another problem now left.

00:44:51.000 --> 00:44:59.000
So the next problem that we had. Was that there was something that we call dispersion.

00:44:59.000 --> 00:45:06.000
Nerical models for tsunami, if they are only. They don't really have this.

00:45:06.000 --> 00:45:11.000
These bundle is what we are showing is the swath observation here.

00:45:11.000 --> 00:45:16.000
And we can see that after the main. The main way. There's a lot of structure bind.

00:45:16.000 --> 00:45:22.000
Then we generated a synthetic swot track, using 60,000 tight gauges.

00:45:22.000 --> 00:45:25.000
给大约，也就是times as well。

00:45:25.000 --> 00:45:28.000
And we don't see any of that dispersion here, or any structural.

00:45:28.000 --> 00:45:34.000
我们的。能够recover a little bit more of that structure。

00:45:34.000 --> 00:45:38.000
So apparently including this person, is quite.

00:45:38.000 --> 00:45:41.000
比如说我们。

00:45:41.000 --> 00:45:45.000
we could. Talk about it. Offline any time.

00:45:45.000 --> 00:45:50.000
But definitely they need to have that discretion seems to be important.

00:45:50.000 --> 00:45:55.000
And let's take a little bit more of a look at the structure of that expression that is, of social.

00:45:55.000 --> 00:45:58.000
Swat on just as light.

00:45:58.000 --> 00:46:00.000
书名都在。

00:46:00.000 --> 00:46:10.000
We looked at the elevation over time. Then we could see that there is the main wave, and then there's a little bit.

00:46:10.000 --> 00:46:16.000
Along the the. But if we looked at 2 sides of the swats.

00:46:16.000 --> 00:46:20.000
So one like on the. The eastern on the west, or that.

00:46:20.000 --> 00:46:23.000
That has a lot more resolution, and we can see.

00:46:23.000 --> 00:46:26.000
High, high resolution.

00:46:26.000 --> 00:46:28.000
还availability，我们还能。

00:46:28.000 --> 00:46:31.000
Mainly that just the regular ultimate.

00:46:31.000 --> 00:46:37.000
Which is similar to. And i'll just dive a little bit more into this one.

00:46:37.000 --> 00:46:39.000
These zoom out in this window.

00:46:39.000 --> 00:46:42.000
我们的问题。

00:46:42.000 --> 00:46:45.000
We have in the orange and in the green line.

00:46:45.000 --> 00:46:51.000
That we do not see han in the. Even in the in the regular ultimate.

00:46:51.000 --> 00:46:55.000
And this is something that is possibly knows, and we're still working on that.

00:46:55.000 --> 00:46:57.000
Hopefully. We'll get that.

00:46:57.000 --> 00:47:01.000
我已经in the end。We had a very nice model。

00:47:01.000 --> 00:47:04.000
The model that we had the models.

00:47:04.000 --> 00:47:07.000
小子using this person。

00:47:07.000 --> 00:47:11.000
It actually includes more of that viability that we're seeing.

00:47:11.000 --> 00:47:15.000
什么的。

00:47:15.000 --> 00:47:19.000
Legal created these videos a fantastic movie. I think.

00:47:19.000 --> 00:47:24.000
nevertheless, like the model sort of. Gets better with that.

00:47:24.000 --> 00:47:29.000
But we still have work to do. And here quickly, just jp into smary.

00:47:29.000 --> 00:47:32.000
We have a new pair of glasses from sky swots.

00:47:32.000 --> 00:47:37.000
的。

00:47:37.000 --> 00:47:42.000
Sort of data for showing the observations for the tsunami wave field.

00:47:42.000 --> 00:47:45.000
Tsunamis are way more complex. That's what it's showing us what.

00:47:45.000 --> 00:47:50.000
And it's exposing some gaps. There's. Some things that we don't know.

00:47:50.000 --> 00:47:54.000
There was a lot of talking about why these super big magnitude.

00:47:54.000 --> 00:47:57.000
Did not do that much destruction, so it seems that.

00:47:57.000 --> 00:48:05.000
Not only the rock, not the magnitude, only. But the route to his style. It's also important, nevertheless, it's.

00:48:05.000 --> 00:48:11.000
A good example to study. And we have future work definitely what.

00:48:11.000 --> 00:48:16.000
说的是，在。我们的。

00:48:16.000 --> 00:48:18.000
The mothers.

00:48:18.000 --> 00:48:24.000
Going to help us, probably to understand what is missing in the forecast and the physics about.

00:48:24.000 --> 00:48:36.000
Around tonight so we have a lot of work to do and thank you very much for your attention.

00:48:36.000 --> 00:48:46.000
Great. Thank you, angle. up. Next we have pipeline at at use usc with observations of the.

00:48:46.000 --> 00:48:59.000
2025 contracts, tsunami in california, and a story about being in pretty much the right time, pretty much the right place at pretty much the right time.

00:48:59.000 --> 00:49:03.000
Everyone. My name is patrick lynette, from the university of southern california.

00:49:03.000 --> 00:49:10.000
I'd like to talk about today is a few rapid response. Observations in california harbors.

00:49:10.000 --> 00:49:16.000
During the 2025 kamchatka earthquake. So what we're going to focus here on crescent city in santa cruz.

00:49:16.000 --> 00:49:22.000
I got 2 pretty valuable datasets from these locations. What you're seeing here in this 1st video.

00:49:22.000 --> 00:49:28.000
Is that some of the the later waves, when the sun rose in crescent city.

00:49:28.000 --> 00:49:31.000
earlier in the morning. We'll get more into that as we go through.

00:49:31.000 --> 00:49:36.000
So the 1st event i do want to talk about is this tsunami.

00:49:36.000 --> 00:49:41.000
The impact in crescent city harbor. So this is a kind of an interesting story.

00:49:41.000 --> 00:49:47.000
One of these situations, where it just happened to be in a place where i could go to see the tsunami.

00:49:47.000 --> 00:49:51.000
So i had traveled from LA. Up to corvallis.

00:49:51.000 --> 00:49:55.000
During the day in july 29, th and i had just about gotten to my hotel room.

00:49:55.000 --> 00:49:59.000
Late afternoon i was starting to work on my talk for the next day.

00:49:59.000 --> 00:50:04.000
That around 4 30. The 1st email from the pacific tsunami warning centre came in.

00:50:04.000 --> 00:50:11.000
And it showed a magnitude. 8. When you see magnitude 8 kind of used to this on this this 1st advisory.

00:50:11.000 --> 00:50:18.000
A pretty solid chance that it's not going to stay at an 8 and a decent chance that it goes up potentially, significantly. So at that point.

00:50:18.000 --> 00:50:23.000
You start email chatting with my cgs colleagues, jay, patten and nickrail.

00:50:23.000 --> 00:50:26.000
about what the response in california might look like.

00:50:26.000 --> 00:50:31.000
In particular, what in northern california the tsunami impacts may be.

00:50:31.000 --> 00:50:35.000
So at that point i do start thinking about the drive. So i'm up in corvallis again.

00:50:35.000 --> 00:50:39.000
I'm looking at this in army travel time, maps that the warning centers post and.

00:50:39.000 --> 00:50:43.000
Doing some of my own calculations, and it's about 8 h.

00:50:43.000 --> 00:50:46.000
So from source to crescent city. We have about 8 h of time.

00:50:46.000 --> 00:50:51.000
By the time i'm looking about this we're only about 30 min in, so i also look at crescent.

00:50:51.000 --> 00:50:55.000
City travel time, so it's not close by any stretch, but it's.

00:50:55.000 --> 00:51:06.000
It's 5 h away, meaning that if i hopped in the car right then, and drove all the way down to crescent city. I'd be there a few hours before this tsunami. So at that point i realized, hey.

00:51:06.000 --> 00:51:10.000
It's a potential observation of a tsunami which you don't really get.

00:51:10.000 --> 00:51:14.000
To do that often, especially in a place like crescent city.

00:51:14.000 --> 00:51:18.000
So i'm starting to think about it. Get myself together.

00:51:18.000 --> 00:51:22.000
Talking to the workshop organizers to say, hey, i might not be there.

00:51:22.000 --> 00:51:28.000
For the workshop in the morning the next day, and then the 1st dark time series come in and.

00:51:28.000 --> 00:51:35.000
We see the signal over here on the right. So if you're not familiar with these that red signal.

00:51:35.000 --> 00:51:43.000
Is kind of a typical earthquake signal at 15 second sampling frequency, and then the green line follows on about 1 min sampling frequency, so.

00:51:43.000 --> 00:51:47.000
We're we're looking at that green line, and it's got a period of.

00:51:47.000 --> 00:51:51.000
Something in the ballpark of. 5 ish minutes. It's got an amplitude.

00:51:51.000 --> 00:51:55.000
Something on the order of a meter. Could that be the tsunami.

00:51:55.000 --> 00:52:02.000
Well, if you, if you look at travel time, it's too early, so it's probably not the tsunami, but at that point. We're also thinking. Well.

00:52:02.000 --> 00:52:06.000
That's not the tsunami. It's probably a pretty long earthquake.

00:52:06.000 --> 00:52:14.000
And so i'm thinking, all right. I'm getting in the car. This is gonna be one worthwhile seeing. And so by 5 20, about an hour. After that 1st email.

00:52:14.000 --> 00:52:17.000
I just get myself in the car, and that's when.

00:52:17.000 --> 00:52:22.000
The actual tsunami shows up on that closest dart, and it's a big signal. And so whenever you see a.

00:52:22.000 --> 00:52:27.000
Crest to troughs, tsunami in the deep ocean. greater than a meter.

00:52:27.000 --> 00:52:32.000
You know that the game is on, so to speak, and there will be a tsunami. So i was.

00:52:32.000 --> 00:52:40.000
Pretty confident at that point that i would get to crescent city, and there would be a tsunami there to observe at this point i didn't quite know how big it would be.

00:52:40.000 --> 00:52:45.000
at 6 pm. Just about to eugene. At this point.

00:52:45.000 --> 00:52:55.000
The earthquake gets upgraded to an 8.7. i looked through my google maps. And i say, all right. Well, i'm going to get to christmas city. It's gonna be dark.

00:52:55.000 --> 00:53:03.000
it'd be cool to be there, but it would be nice to at least take some video measure measurements. So i stopped at best, buy a hardware store, and eugene.

00:53:03.000 --> 00:53:09.000
get a bunch of cameras and lights and batteries, some memory cards, clamps, and tape.

00:53:09.000 --> 00:53:15.000
So ye anything that i could get that would allow me to take some visual measurements of the tsunami.

00:53:15.000 --> 00:53:22.000
With. There's really no lead time. Plan was to meet john all's walled at citizens dock.

00:53:22.000 --> 00:53:25.000
And at this point, and as i'm driving down a couple of hours away.

00:53:25.000 --> 00:53:30.000
crescent city is in a tsunami warning. They're at a fairly high evacuation phase.

00:53:30.000 --> 00:53:37.000
I'm a little bit concerned that access will be restricted to the harbour, since they probably don't want people down there.

00:53:37.000 --> 00:53:50.000
No. As we're going down. I'm talking to nick and jay as well, and we're looking at the forecasts for chris and city, and these are coming in at somewhere between 2 and a half to 5 foot.

00:53:50.000 --> 00:53:54.000
wave heights. And so i'm looking at those nbers, and i'm.

00:53:54.000 --> 00:54:02.000
I'm not too concerned about inundation at the harbor, recognizing that these aren't perfect, but they're probably going to be quite good, so i felt.

00:54:02.000 --> 00:54:06.000
Confident that we would be all right to set up some cameras at the harbor, and do some observations.

00:54:06.000 --> 00:54:11.000
Arrive at the harbor about 1130, about 30 min before the forecasted 1st waves.

00:54:11.000 --> 00:54:15.000
And there is no one's stopping, no one checking the harbor's open.

00:54:15.000 --> 00:54:19.000
We just drive right in. And we start to set up some cameras.

00:54:19.000 --> 00:54:26.000
A little bit about crescent city before we get into the details. So crescent city it's a well-knowns, tsunami hotspot. There are.

00:54:26.000 --> 00:54:35.000
A nber of amplification. Lenses, so to speak, which focus energy right on crescent city, and inside the harbor.

00:54:35.000 --> 00:54:46.000
The harbor itself was largely destroyed in 2,011. And it was real rebuilt to be an example. Tsunami, resistant harbor. You have very large.

00:54:46.000 --> 00:54:54.000
Piles. New docs. There's a tremendous amount of capacity and strength at creston city harbour.

00:54:54.000 --> 00:54:59.000
The doc. I'll focus on a little bit. Here is this so-called h. Doc right here.

00:54:59.000 --> 00:55:08.000
So h. Duck is a unique duck in the harbor. It's a deflector duck. It's meant to diffuse the tsunami energy kind of to protect the docs bind it.

00:55:08.000 --> 00:55:14.000
What we expect to happen during a tsunami is the current jet in through the entrance, like. So following this blue line.

00:55:14.000 --> 00:55:19.000
You put this deflector doc here, which has a relatively large draft here, about 2 feet.

00:55:19.000 --> 00:55:25.000
so that it blocks the current, diffuses it, pushes it around It did show to be quite effective.

00:55:25.000 --> 00:55:30.000
At protecting the docs bind it. We'll talk more about that in a second.

00:55:30.000 --> 00:55:36.000
Alright. So the tsunami finally gets there. The 1st few waves arrive at around 1230.

00:55:36.000 --> 00:55:46.000
and a relatively small and long in period. There are a handful of others at the harbor, there to see the tsunami.

00:55:46.000 --> 00:55:51.000
Some of them are in a slightly more. celebrative mode.

00:55:51.000 --> 00:55:56.000
Maybe not fully aware of the situation that they were in.

00:55:56.000 --> 00:56:09.000
ye We tried to educate them for a little bit, while we realized We maybe we're wasting our breath. But after the 1st hour and change of nothing significant, essentially the water level and the harbor going up and down.

00:56:09.000 --> 00:56:16.000
About a foot over the course of. Tens of minutes. They're mostly disappointed, and all but a few of them leave.

00:56:16.000 --> 00:56:19.000
So you can see here the total signal for the event.

00:56:19.000 --> 00:56:25.000
A comicing about 10 h. and the wavelet below it.

00:56:25.000 --> 00:56:33.000
You see these initial waves come in with 2 dominant piers around 20 and 35 min, and then, after a while, you see the.

00:56:33.000 --> 00:56:38.000
The basin scale resonance setup, and you have this very strong band of energy.

00:56:38.000 --> 00:56:43.000
At around 25 min, which is controlling these. These these highly persistent.

00:56:43.000 --> 00:56:46.000
Fairly significant ways. Right? These are crust. The trough of 6 feet.

00:56:46.000 --> 00:56:52.000
Waves in creston city harbor that went on for many, many hours after the 1st wave.

00:56:52.000 --> 00:56:57.000
Actual. About 1 30, the larger of the waves begin. This is a time lapse video.

00:56:57.000 --> 00:57:11.000
field of view here in this. Purple triangle, kind of looking at the center of the harbor, and you'll see what a seven-foot crested trough looks like on these floating docs, and this is exactly what floating docs are supposed to do.

00:57:11.000 --> 00:57:15.000
They rise and fall with the tsunami. As long as the tsunami doesn't rise and fall.

00:57:15.000 --> 00:57:24.000
Too quickly. So again, this is that 1st big wave. No damage occurred during this big wave. Everything kind of goes up and down throughout the harbor.

00:57:24.000 --> 00:57:29.000
Can see we weren't too worried about our safety. We're out there inspecting the pile of guides and the piles.

00:57:29.000 --> 00:57:40.000
Now at 2 30 a m. We get a big wave that comes in quite quickly, so you'll see in this time lapse. So now you're looking at h. Doc a little bit further to the south.

00:57:40.000 --> 00:57:47.000
You have a drawdown, and then a very large flooding wave.

00:57:47.000 --> 00:57:52.000
This will go back down again. And the next wave that comes in.

00:57:52.000 --> 00:58:00.000
if you look closely in the background, you will see it right at the end of the video it will submerge one of these sections in hdoc.

00:58:00.000 --> 00:58:07.000
We overtops it and goes down. And so that is the the point. In time where the 1st significant damage occurred to hdoc.

00:58:07.000 --> 00:58:13.000
Again. This is 1230 a. M. This is 2 h after the 1st waves arrived.

00:58:13.000 --> 00:58:24.000
What is particularly fascinating about this event? And it underscores a bit why, it's so important to get out in the field and look at things as they happen.

00:58:24.000 --> 00:58:32.000
Is that this section of h. Doc which failed, and jay is going to give you a little bit more detail in the next presentation, because he he checked it out the day after.

00:58:32.000 --> 00:58:37.000
you will see. We zoom in right on hdoc.

00:58:37.000 --> 00:58:40.000
if you focus on this white, and it kind of looks like a.

00:58:40.000 --> 00:58:44.000
Fire hydrant. It's an electric panel that's connected to the floating dock.

00:58:44.000 --> 00:58:47.000
You will see that as the water level is rising.

00:58:47.000 --> 00:58:53.000
Initially the dock rises with it, but then at some point the dock just goes down. It sinks.

00:58:53.000 --> 00:58:57.000
And it quite literally thinks it gets pulled down.

00:58:57.000 --> 00:59:04.000
The only obvious explanation for this is that because you have have this.

00:59:04.000 --> 00:59:13.000
Relatively large draft on the dock. The tsunami current gets pushed underneath that dock. It accelerates.

00:59:13.000 --> 00:59:24.000
That speed up decreases the pressure. So you have a pull down, or a suction force underneath it, and that negative pressure was large enough to overcome the residual buoyancy of the dock.

00:59:24.000 --> 00:59:29.000
Pulling the whole dock underneath it. So again, important to be there and see these things.

00:59:29.000 --> 00:59:35.000
If no one was there to videotape this event, and they just looked at the docs after the.

00:59:35.000 --> 00:59:38.000
Fact, in the morning when the sunlight came up.

00:59:38.000 --> 00:59:44.000
They would have looked at the docked and said, oh, well, the guide must have stuck to the pile, or something got kinked.

00:59:44.000 --> 00:59:53.000
or some sort of traditional failure happened. Where, in fact, the video shows that it wasn't really a traditional failure. It was this negative buoyancy failure.

00:59:53.000 --> 01:00:03.000
Which should be relatively straightforward to design against. if you can truly understand and isolate the mechanism.

01:00:03.000 --> 01:00:14.000
so these waves Again like i said. They persisted for many hours. This is that 1st video. As soon as the daylight comes up, and so keep in mind at this point.

01:00:14.000 --> 01:00:20.000
Stolen a tsunami warning, still seeing waves, crescent trough of greater than 6 feet.

01:00:20.000 --> 01:00:32.000
but Mariners fishing fleet. I guess they're built a little different in northern california, and so what we would see in the morning. Were these fishing vessels that would time. The slack currents.

01:00:32.000 --> 01:00:35.000
Of the tsunami to get back into the harbour.

01:00:35.000 --> 01:00:40.000
and inside the harbor. If you were away from h. Doc, you were pretty safe.

01:00:40.000 --> 01:00:49.000
So what you will see as this boat comes in is that he's kind of skidding a little bit on the currents, but he's also very clearly in this slack current phase.

01:00:49.000 --> 01:00:54.000
and he will dart through and within.

01:00:54.000 --> 01:01:02.000
30 seconds bind him. The currents are bridging at somewhere around 6 knots, and you'll start to see that come in. So there he goes in.

01:01:02.000 --> 01:01:09.000
Then i'll just zoom this forward a little bit, see the current start to build, start, to build, start, to build, start, to build.

01:01:09.000 --> 01:01:13.000
And there you go. So that's about 45 seconds after he came in. That's what the currents looked like.

01:01:13.000 --> 01:01:19.000
So all the credit to him. He timed it well. Whether it was safe or not, i would say it not.

01:01:19.000 --> 01:01:24.000
but just to the point these currents in crescent city, harvard did persist for quite a long time.

01:01:24.000 --> 01:01:29.000
I i stayed conscious through most of the morning.

01:01:29.000 --> 01:01:35.000
And then right around 9 a. M. And i get back on the road, make it up to.

01:01:35.000 --> 01:01:42.000
Corvels. Give him a talk of the workshop and give everyone an update on what i saw. So it was a. It was a busy day, but i think very important observations, particularly on the.

01:01:42.000 --> 01:01:49.000
Engineering side on marine structures. Alright. So that was kristen city. Let's talk about santa cruz harvard. So.

01:01:49.000 --> 01:01:57.000
This particular dataset. I expect. From santa cruz harbor is going to turn into something extremely useful, both in terms of understanding.

01:01:57.000 --> 01:02:03.000
some of the hydrodynamics, the physics of tsunamis in harbors, but also just for general model, bencarking.

01:02:03.000 --> 01:02:09.000
So the usgs had installed an 80 cp near the entrance to santa cruz harbor. Down here.

01:02:09.000 --> 01:02:14.000
And this was done by a team of people who are noted in the banner at the bottom of the slide.

01:02:14.000 --> 01:02:20.000
But also in the couple hours before the event, similar to how i got down to crescent city.

01:02:20.000 --> 01:02:27.000
Sean, paul desel and jay padget got a couple of hobo's, put one on the bridge and put one on a pile in the northern part of the harbor.

01:02:27.000 --> 01:02:36.000
And between this data set we now have inside a harbor we have 2 free surface elevation time series and one full adcp. So it's.

01:02:36.000 --> 01:02:48.000
Velocities and velocity, profiles in time. That adcp recorded about 12 h of tsunami currents in a harbor. So this is extremely rare instrental data.

01:02:48.000 --> 01:02:58.000
almost one of a kind. One of the things that you see interesting is that before the tsunami arrived here, you do see these oscillations in the current.

01:02:58.000 --> 01:03:08.000
So you have this pre-sunami about 16 min resident mode, and if you look in the literature, you have a whole lot of bay, wide, resonant modes in crescent city. That's 16.5 is one of them.

01:03:08.000 --> 01:03:16.000
And so there's probably an anti-note of that mode outside of santa cruz harbor, always bouncing around at about 16 and a half minutes.

01:03:16.000 --> 01:03:19.000
When you look at that wavelet, you can also see this.

01:03:19.000 --> 01:03:24.000
Blob of energy at slightly higher frequencies, higher frequencies, lower periods, and these are probably.

01:03:24.000 --> 01:03:30.000
harbor of resonant modes. So i'll end with just this animation.

01:03:30.000 --> 01:03:37.000
Showing this adcp data that we have, and these these profiles of velocity.

01:03:37.000 --> 01:03:46.000
That we have in the water coln. It's gonna be very useful to understand some of these dynamics and some of the turbulence and some of the mixing.

01:03:46.000 --> 01:03:49.000
That we we expect to see when these currents are strong inside harbors.

01:03:49.000 --> 01:03:56.000
So in there thanks very much.

01:03:56.000 --> 01:04:02.000
Great. Thank you, pat, And last but not least, we have jay, pat, california, geological survey.

01:04:02.000 --> 01:04:08.000
Who's going to talk about how tsunami hazards in san francisco bay are determined, and.

01:04:08.000 --> 01:04:15.000
We'll expand on the fever dream of of responding to an event such as the conchaka snobby.

01:04:15.000 --> 01:04:23.000
The california geological survey and the california governor's office of emergency services comprised the california tsunami program.

01:04:23.000 --> 01:04:28.000
We also partner with doctors pat lane at and honky theo.

01:04:28.000 --> 01:04:34.000
Drinks, tsunami events. We work together with the national tsunami warning center and the national weather service weather forecast offices.

01:04:34.000 --> 01:04:39.000
To provide guidance to the 1st responders that have authority to respond to tsunami events.

01:04:39.000 --> 01:04:47.000
We 1st present present the probabilistic tsunami hazards, analyses we conducted in the san francisco bay area.

01:04:47.000 --> 01:04:53.000
Then we discussed the tsunami from the magnitude 8.8 kamchaka, russia earthquake.

01:04:53.000 --> 01:04:59.000
There are about 85% of tsunami are caused by large earthquakes below the seafloor.

01:04:59.000 --> 01:05:04.000
Thrust can be caused by landslides, volcanic eruptions, blood impacts.

01:05:04.000 --> 01:05:11.000
Like asteroids and meteorological phenomena. This is a map of earth's main tectonic plates.

01:05:11.000 --> 01:05:16.000
The red arrows indicate the direction of relative movement at the plate. Boundaries.

01:05:16.000 --> 01:05:22.000
There are 3 3 types of plate batteries. Divergent, convergent.

01:05:22.000 --> 01:05:33.000
And transform, like the sand and race vault. Each type can generate tsunami, though convergent, plate, battery, earthquake, generate the largest and most devastating.

01:05:33.000 --> 01:05:42.000
There are other falls in california that are capable of generating tsunami, but the cascadia seduction zone has the potential for generating the largest tsunami waves.

01:05:42.000 --> 01:05:48.000
In the lower right animation. We see how the cos seismic motion can generate tsunami waves.

01:05:48.000 --> 01:05:54.000
On the left is a map, showing where the oceanic plates seduct beneath the continental plate.

01:05:54.000 --> 01:06:03.000
In the upper right note the cross. Section 8. A prime shows how the ground moves between, and during earthquakes.

01:06:03.000 --> 01:06:09.000
Ptha is a process used to develop a framework to inform tsunami modeling and hazards, analyses.

01:06:09.000 --> 01:06:19.000
This process uses a logic tree approach to. Collate the entire suite of possible and probable sonomagenic bavior of tsunami sources relevant to the area of interest.

01:06:19.000 --> 01:06:24.000
A logic tree is a way to calculate the relative likelihood for each of all possible scenarios.

01:06:24.000 --> 01:06:35.000
For a given phenomenon. This map shows the main subduction zones around the pacific basin. These blue rectangles, called fault elements, are generally the tsunami sources we used.

01:06:35.000 --> 01:06:45.000
To develop the ptha for california. Tsunami modelers inherit the greens function method developed by seismologists.

01:06:45.000 --> 01:06:49.000
To apply slip distributions to unit tsunami model results.

01:06:49.000 --> 01:06:55.000
Though sometimes tsunami greens, functions are done in the reverse direction, from the wave to the source.

01:06:55.000 --> 01:07:03.000
Steps, one through 3. Use unit slip on a single fault. Element to generate okada style, uplift of the seafloor.

01:07:03.000 --> 01:07:07.000
Which is basically the initial wave size of the surface of the ocean.

01:07:07.000 --> 01:07:11.000
Step 4 is to model this way of transport across the ocean basin.

01:07:11.000 --> 01:07:19.000
The resulting amplitude represents this unit slip. Step 5. Consider a slip distribution, a multiple of the unit slip.

01:07:19.000 --> 01:07:25.000
Step 6. Use them that multiplicative factor to scale the waveform for each fault element.

01:07:25.000 --> 01:07:32.000
And finally step 7, some all waveforms to get the resultant tsunami wave.

01:07:32.000 --> 01:07:37.000
The logic tree is used to constrain the slip distributions for thousands of tsunami simulations.

01:07:37.000 --> 01:07:42.000
The outputs from these tsunami models result in a suite of offshore. Tsunami heights.

01:07:42.000 --> 01:07:48.000
The blue lines in the left plot that represent the chance for tsunami sizes on the horizontal axis.

01:07:48.000 --> 01:07:52.000
For a given annual probability of exceedance on the vertical axis.

01:07:52.000 --> 01:07:57.000
This amplitudes are calculated for points along the 100 meter isobath.

01:07:57.000 --> 01:08:00.000
Where the shallow water wave equation is still valid.

01:08:00.000 --> 01:08:07.000
Using these results plotted on the right, we calculate the mean offshore wave amplitude. This is the offshore hazard curve.

01:08:07.000 --> 01:08:14.000
With a unique point. The next step is to choose sources that generate waves that match the hazard curve for.

01:08:14.000 --> 01:08:27.000
Or arps. Inundation models where we need to use nonlinear bozemesque wave models.

01:08:27.000 --> 01:08:32.000
The cgs worked with calories and local partners to prepare tsunami hazard area maps.

01:08:32.000 --> 01:08:41.000
Based on these ptha results. Most all of california. The tha. Is based on the 975 year arp tsunami, model.

01:08:41.000 --> 01:08:47.000
This maps can be viewed and downloaded from tsunami ca.gov.

01:08:47.000 --> 01:08:54.000
These evacuation maps show the tsunami hazard area and one color, and the area outside of the hazard area and a different color.

01:08:54.000 --> 01:09:00.000
To avoid harm from a tsunami wave move outside of the tsunami hazard area.

01:09:00.000 --> 01:09:04.000
Let's look at some ptha data for the sfbay area.

01:09:04.000 --> 01:09:12.000
Show from left to right the 100 475, 975, and 2,475 year arp maxim amplitudes.

01:09:12.000 --> 01:09:20.000
Dark of blue, represents larger wave amplitudes. There's a legend in the upper left, showing the difference between wave height and amplitude.

01:09:20.000 --> 01:09:26.000
Places with blue landward of the black line. The coastline represent places where there is inundation.

01:09:26.000 --> 01:09:36.000
Note how the 2 maps on the right show how the golden gate constricts tsunami flow, reducing the amplitude within the san francisco bay.

01:09:36.000 --> 01:09:41.000
Here's a profile through the golden gate, across the 2475 data.

01:09:41.000 --> 01:09:49.000
Note. There's a reduction in amplitude of about 5 meters over a 5 kilometer span.

01:09:49.000 --> 01:09:56.000
These larger-scale maps show how these 4 arp amplitude models compare to the usgs campus at moffat field.

01:09:56.000 --> 01:10:02.000
The map on the left has the tsunami hazard area transparently overlaying upon the rest of the map.

01:10:02.000 --> 01:10:09.000
Remember yellow represents the tha. And know how the usgs campus is fully outside of the tha.

01:10:09.000 --> 01:10:19.000
It may be difficult to see, but the 100 year arp amplitude data are represented by sliver of blue within a tidal canal on the upper left.

01:10:19.000 --> 01:10:24.000
Also note how the 2 maps on the right show inundation beyond the tha boundary.

01:10:24.000 --> 01:10:30.000
This is because the tsunami modeling is course at 1 3rd arc, second, nominally 10 meters in a resolution.

01:10:30.000 --> 01:10:36.000
The modeling cannot see features like levies. Jackie bought who mapped the THA. Here.

01:10:36.000 --> 01:10:43.000
And verify by rick wilson in the field, use lighter data and field verification to show that the tsunami.

01:10:43.000 --> 01:10:52.000
Likely won't inundate beyond the tha boundary. You receive the maxim tsunami velocities for the same arps.

01:10:52.000 --> 01:10:56.000
Lower velocity is a lighter color, and higher velocity is a darker color.

01:10:56.000 --> 01:11:02.000
Based on empirical evidence, damage to harbours and marinas can initiate at velocities around 3 knots.

01:11:02.000 --> 01:11:06.000
which is about one and a half meters per second.

01:11:06.000 --> 01:11:11.000
Larger vessels travel between 6 and 12 nights within the bay, so we highlighted.

01:11:11.000 --> 01:11:18.000
The 5 meter per second contour, which is about 10 knots. Let's zoom in.

01:11:18.000 --> 01:11:22.000
You're a larger-scale mouse, for the golden gate north is not always up.

01:11:22.000 --> 01:11:26.000
We labeled some of the 5 and 10 metres per second contours.

01:11:26.000 --> 01:11:31.000
The safe threshold for vessel traffic is lower than the 6 to 12 knots.

01:11:31.000 --> 01:11:43.000
Eddie's, from. Form and make things more complicated than simply the maxim velocity. It is not a smart plan to attempt to traverse this region during tsunami events.

01:11:43.000 --> 01:11:51.000
The 29, july 2025, magnitude 8.8. Earthquake slipped along the mega thrust fault that forms of kamchaka subduction, zone.

01:11:51.000 --> 01:11:55.000
Let's take a look at the earthquake and the tsunami.

01:11:55.000 --> 01:12:01.000
And the usgs illustration. On the left we see how the pacific plate subducts beneath the octoesk plate.

01:12:01.000 --> 01:12:06.000
The map in the upper right shows us lab contours, with a yellow star showing the 8.8.

01:12:06.000 --> 01:12:12.000
Epicenter. Below the map is a low angle, oblique view of from the north.

01:12:12.000 --> 01:12:19.000
在wards。 Using inversions of GPS data on the left.

01:12:19.000 --> 01:12:24.000
Bergmann and others show on the right that coupling of the mega thrust is likely to be heterogeneous.

01:12:24.000 --> 01:12:33.000
Higher rates of coupling are in red. This is a map from mckins at l. 2010, showing outlines of historic earthquake ruptures.

01:12:33.000 --> 01:12:40.000
Their research, sought to refine the slip distribution for the 1952 magnitude 8.8 to 9 kamchaka earthquake.

01:12:40.000 --> 01:12:46.000
The 1952 epicenter as a white star, and the rupture area is the largest gray polygon.

01:12:46.000 --> 01:12:51.000
These geologists explored different possible slip distributions to create tsunami models.

01:12:51.000 --> 01:12:56.000
Then they compared tsami model results with field observations from tsunami run-up.

01:12:56.000 --> 01:13:02.000
The 1952. Trans. Pacific tsunami generated significant damage across the pacific basin.

01:13:02.000 --> 01:13:13.000
Including in hawaii and in california. This is what we at the ctp had in our minds as we went to work responding to the 2,025 tsunami.

01:13:13.000 --> 01:13:19.000
Earlier, johnson and sataki use inversions of taige data to estimate the slip distribution.

01:13:19.000 --> 01:13:25.000
For this 1,952 earthquake. Color in red, represents a slip distribution and note the largest slip.

01:13:25.000 --> 01:13:29.000
Was on the downtip part of the mega, thrust.

01:13:29.000 --> 01:13:32.000
On the left are mckins, at l. Slip distributions.

01:13:32.000 --> 01:13:36.000
Now on the right are the 5 best-fit distributions of slip.

01:13:36.000 --> 01:13:41.000
To the right of each slip. Distribution are the tsunami and model results plotted along the coast.

01:13:41.000 --> 01:13:51.000
Symbols represent tsunami, run-up elevations, and the color of each bar represents, whether the model results are an underestimate in cream and approximate match in dark blue.

01:13:51.000 --> 01:13:58.000
Or an overestimate in red, and note that the maxim slip may have been up to 28 meters.

01:13:58.000 --> 01:14:03.000
This poster shows that tectonic setting and impacts from the magnitude 8.8 earthquake.

01:14:03.000 --> 01:14:08.000
Note the cross-section c. To c. Prime, shown on as line on the map.

01:14:08.000 --> 01:14:13.000
This usgs. Cross-section is the upper. So in the upper center shows historical seismicity.

01:14:13.000 --> 01:14:17.000
Associated with the subducting plate going down to the west.

01:14:17.000 --> 01:14:23.000
On the main map. The orange circles in the center represent aftershock locations from the 8.8 earthquake.

01:14:23.000 --> 01:14:27.000
We plot the largest magnitude after sharks and aftershocks.

01:14:27.000 --> 01:14:32.000
And foreshocks in green and blue, which coincides especially with the main shock.

01:14:32.000 --> 01:14:40.000
This is like. There's likely a reason for this, such as a seamout, fracture, zone, or some other feature on the seducting pacific plate.

01:14:40.000 --> 01:14:45.000
Also applauded are the usgs gram failure and intensity data products.

01:14:45.000 --> 01:14:53.000
Here we overlay this. The sataki johnson slip distribution, which almost perfectly alliance with the 2025 aftershock pattern.

01:14:53.000 --> 01:15:00.000
The gray slip is down, dip. And here we overlaid the usgs slip. Distribution also aligned with the aftershocks.

01:15:00.000 --> 01:15:09.000
The gray slip is in the uptip part of the mega thrust, though these 2 slip models were constrained by inversions based on quite different data, sets.

01:15:09.000 --> 01:15:17.000
And a vastly different resolutions. Note, the slip may has been as much as 40 meters.

01:15:17.000 --> 01:15:25.000
We at the state were to nonstop for 39 h between earthquake and the final cancellation by the ntwc.

01:15:25.000 --> 01:15:28.000
My personal lesson was to have food and my work desk.

01:15:28.000 --> 01:15:37.000
But i refuse to wear diapers. Here's a comparison between the 1952 on top and the 2025 on bottom, camchaka tsunami.

01:15:37.000 --> 01:15:43.000
As recorded at the crescent city tie gauge. The maxim wave heights were nearly identical.

01:15:43.000 --> 01:15:49.000
2 2.0 3 meters and 1952 and 2.0 1 meters and 2025.

01:15:49.000 --> 01:15:55.000
This was a coon observation. At other locations throughout the pacific.

01:15:55.000 --> 01:16:01.000
Here are the tigee data from the sfba area, where the tsunami was much smaller in size.

01:16:01.000 --> 01:16:08.000
Note how the wave is largest at the sf. Tide gauge and smaller at alameda enricent.

01:16:08.000 --> 01:16:15.000
This plot shows tsunami water surface elevation. Observations from tight gauge has plotted north to south, left to right.

01:16:15.000 --> 01:16:21.000
The maxim wave height is plotted in light green, the maxim amplitude in in dark green.

01:16:21.000 --> 01:16:27.000
And the maxim observed water surface elevation. Data are plotted as light yellow circles.

01:16:27.000 --> 01:16:34.000
The crescent city arena cove. In santa barbara. Tai gauges were the hotspots. For this tsunami.

01:16:34.000 --> 01:16:42.000
The cgs prograatically gathers fragile and perishable information, following earthquake, volcanic corruption and tsunami events.

01:16:42.000 --> 01:16:51.000
The field data collected can be used to better understand these hazards. These data are collected under coordination by the california earthquake clearing house.

01:16:51.000 --> 01:17:02.000
Chaired by kate thomas at the cgs. Dr. Patelinette was at a workshop in corvallis when the earthquake happened, and we iediately started recording coordinating his field visit.

01:17:02.000 --> 01:17:06.000
To the kristen city harbor, where lynette met with cgs staff.

01:17:06.000 --> 01:17:13.000
This video shows some of the observations they made, including how a dock got sucked down beneath the water surface.

01:17:13.000 --> 01:17:18.000
Note the electrical explosions.

01:17:18.000 --> 01:17:31.000
As part of the cgs postedomi response program. I sent myself to the harbor the next day. Here's a photo showing the imprecation of the docs. Here. These docs are termed attenuator docs, by the manufacturer.

01:17:31.000 --> 01:17:36.000
Extending a half a metre below the water surface to attenuate currents. Entering the basin.

01:17:36.000 --> 01:17:45.000
In our recently published paper. Led by lynette, we hypothesized that these deeply floating docs formed a nearer opening into the boat basin.

01:17:45.000 --> 01:17:52.000
Creating a venturary effect. This curves the duct to be sucked down below the water level.

01:17:52.000 --> 01:17:56.000
Here we see how the metal flaps that are attached between each dock.

01:17:56.000 --> 01:18:06.000
Broke through the cable installation, causing the explosion seen in the earlier video.

01:18:06.000 --> 01:18:09.000
Hopefully. I've been able to answer questions in the chat.

01:18:09.000 --> 01:18:18.000
Thanks for listening and watching.

01:18:18.000 --> 01:18:22.000
Great thanks, joe. Alright. So i think we have.

01:18:22.000 --> 01:18:35.000
27 min, or the discussion session till 3 30. Don't have any unanswered questions in the chat from jay's talk. Maybe we'll start there and work backwards.

01:18:35.000 --> 01:18:39.000
please raise your hand. If you'd like to ask a.

01:18:39.000 --> 01:18:55.000
Question right now, or type something into the chat.

01:18:55.000 --> 01:19:00.000
Well, okay, i could talk. I could ask a question starting. This is maybe for pat and jay.

01:19:00.000 --> 01:19:11.000
super interesting paper, and observations of that. Of that h. Doc and preston city, sinking.

01:19:11.000 --> 01:19:20.000
Are there plans To redesign the dock. To avoid this situation in the future.

01:19:20.000 --> 01:19:26.000
i would, i would hope so. I i know that the folks there.

01:19:26.000 --> 01:19:30.000
Aware of the mechanism, and there was an engineering team.

01:19:30.000 --> 01:19:38.000
You may have been led by muffin and nicol, and they're probably working with others that went up there to do the engineering inspections and and come up with a plan to fix it.

01:19:38.000 --> 01:19:45.000
So i would. I would expect that the answer is yes, but i don't have a confirmation of that. I mean in the end. It's a.

01:19:45.000 --> 01:19:54.000
Rarely straightforward fix. You just have to add some extra buoyancy on that dock, and if you go through the calculations of the paper. It turns out that.

01:19:54.000 --> 01:20:00.000
The the net force to get that, doc to think was just a few pounds.

01:20:00.000 --> 01:20:07.000
Per foot of dock length so it was right there on the threshold, and so you don't have to put a whole lot of buoyancy on it to keep.

01:20:07.000 --> 01:20:10.000
Floating for that gate.

01:20:10.000 --> 01:20:11.000
Nice.

01:20:11.000 --> 01:20:17.000
we do have a question in the chat. I think this is for jay. You mentioned surprisingly how this is from julian loses.

01:20:17.000 --> 01:20:23.000
You mentioned surprisingly large waves in santa barbara any sense of why that happened there.

01:20:23.000 --> 01:20:33.000
Well, santa barbara, like some of other locations, are frequently hotspots like point san louis.

01:20:33.000 --> 01:20:42.000
And santa cruz, and they're, you know, maybe, because they're south facing, and that had something to do with it. Maybe there was some shoaling.

01:20:42.000 --> 01:20:49.000
I don't know why those are are always. Places where the higher amplitudes are are recorded.

01:20:49.000 --> 01:20:52.000
If does anyone else have any ideas about that.

01:20:52.000 --> 01:21:02.000
So there's that section of that that embayment north when you get to santa barbara, basically between santa barbara and and carpenteria down to ventura, where.

01:21:02.000 --> 01:21:11.000
There's a really strong shelf mode at about 18 min, and so if you can excite that shelf mode, you just keep it rocking and pping and.

01:21:11.000 --> 01:21:14.000
Santa barbara harbor is right at the end. It's at.

01:21:14.000 --> 01:21:19.000
An anti-node of that mode. So if you can get that.

01:21:19.000 --> 01:21:24.000
That mode going which is tsunami can very easily, because that's right. In the wheelhouse of tsunami periods.

01:21:24.000 --> 01:21:41.000
You wind up getting a very persistent strong tsunami in santa barbara. We'd see the same thing even with Big wind wave events where you get infra gravity can PP long periods onto that shelf, and you also get santa barbara harbor residue.

01:21:41.000 --> 01:21:55.000
Tyler. Lodinsky just dropped the question in the chat. Oh, great talk to you. How did the 2025 contracts on me feel data. Compare with tsunami models for california. Where does this event fall within the 9 75 year? Return period? Do you think.

01:21:55.000 --> 01:22:01.000
Alright, that's a great question, and of you know, of course i'd like to spend a little bit more time looking at that.

01:22:01.000 --> 01:22:10.000
But something, you know, 1st order. the 9 75 model shows inundation in most every location along the coast.

01:22:10.000 --> 01:22:21.000
And this kemchaka tsnami didn't. Have much, if all, if at all, any, we didn't observe any inundation.

01:22:21.000 --> 01:22:24.000
It might be that some people did so, it would. It would.

01:22:24.000 --> 01:22:45.000
Probably be much smaller than 975. but something that They were looking into that pat has been helping to work on is using the is taking a look at the forecast amplitudes that the national weather service off. The national tsunami warning center.

01:22:45.000 --> 01:22:52.000
Provides, and we can compare those with the return periods and those offshore locations.

01:22:52.000 --> 01:23:02.000
And so that's a project that we're that we're working on right now. But We haven't. I don't think we've done that yet for kimchaka.

01:23:02.000 --> 01:23:09.000
I hope that helps tyler, said.

01:23:09.000 --> 01:23:14.000
So it so it's much smaller. It was probably much smaller than a 9 75.

01:23:14.000 --> 01:23:17.000
Tsunami.

01:23:17.000 --> 01:23:23.000
Ye and if you look at just the return period of the currents in the harbor, we've had currents that strong.

01:23:23.000 --> 01:23:32.000
Unfortunately, the large nber of times in the past few decades. So it's it's a fairly coon event for crescent city. What we saw for kamchaka.

01:23:32.000 --> 01:23:35.000
Less than 50 years, i would say.

01:23:35.000 --> 01:23:36.000
Right.

01:23:36.000 --> 01:23:42.000
Ye i guess i'm just surprised, because it's such a large event. I would anticipate. It would be larger on the return.

01:23:42.000 --> 01:23:46.000
Period. But that's why i was wondering so.

01:23:46.000 --> 01:23:50.000
Ye And it's also interesting that this same rupture patch.

01:23:50.000 --> 01:23:57.000
Ruptured, you know, 70, with a 75 year spam, you know, from 1952 to 2025.

01:23:57.000 --> 01:24:04.000
And so that's something that you know, we're really sort of confused about also is why was there, you know, a.

01:24:04.000 --> 01:24:10.000
Seduction, zone, earthquake of roughly, a magnitude 9 plus or minus.

01:24:10.000 --> 01:24:17.000
That has basically a whole cycle and 75 years where we typically think of, you know, centuries.

01:24:17.000 --> 01:24:22.000
For a return period for something like that.

01:24:22.000 --> 01:24:34.000
Think it's also interesting. The looking at the run ups from the 1952 event in hawaii they seem to be pretty big compared to the one last year in hawaii, and i.

01:24:34.000 --> 01:24:36.000
I don't know if anyone has thoughts on. Why, that is.

01:24:36.000 --> 01:24:39.000
Maybe just the mode of slip or something.

01:24:39.000 --> 01:24:47.000
And and but and then, if you look at the tiges, some of the tai, most of the tigers in hawaii were all so were identical from between comparing.

01:24:47.000 --> 01:24:48.000
Ye

01:24:48.000 --> 01:24:54.000
52. So ye it's really interesting.

01:24:54.000 --> 01:24:58.000
i don't know if i see any raised hands, i guess one last or another question. Oh, go ead.

01:24:58.000 --> 01:24:59.000
Pretty chris christopher podougo has a raise hand.

01:24:59.000 --> 01:25:01.000
Okay?

01:25:01.000 --> 01:25:02.000
Ye i just wanted to underscore that. What you're looking at would potentially be useful.

01:25:02.000 --> 01:25:07.000
Oh, perfect.

01:25:07.000 --> 01:25:17.000
jay, when we're up all night in our eoc, waiting for the 2 nami to come in. We've got your maps, the state maps, and then we've got those amplitudes.

01:25:17.000 --> 01:25:18.000
Right.

01:25:18.000 --> 01:25:26.000
And we see an amplitude of a few feet or fractions of a foot. And we're like, what does this mean? How does this relate to the 9, 75.

01:25:26.000 --> 01:25:27.000
Ye

01:25:27.000 --> 01:25:32.000
And we don't have that much infrastructure within the tsunami zone. But it would help us make.

01:25:32.000 --> 01:25:40.000
Decisions on whether we should be concerned or not, to have maps like that, or an understanding of how those 2 relate.

01:25:40.000 --> 01:25:47.000
So that's what we're. We? We wanna do is as part of our faster process.

01:25:47.000 --> 01:25:58.000
where we take the amplitudes that the ntwc. Provides, and then we combine that with the tides, the c state that has storm surge.

01:25:58.000 --> 01:26:11.000
And an error, and run up. Values, and then take that output, and and then also Produce a return period estimate for each of those offshore locations.

01:26:11.000 --> 01:26:18.000
And and then we could provide that to the cities and counties and other people that conse those data. And then they could.

01:26:18.000 --> 01:26:29.000
You know, take a look and compare. they're either, if if they have their own pta models, or they could compare it with our ptha models to.

01:26:29.000 --> 01:26:36.000
You know, make an estimate of the impact and make their own decisions. You know we wouldn't make any recoendations, so that what to do.

01:26:36.000 --> 01:26:42.000
But people could conse those data to make their own decisions on on what to do.

01:26:42.000 --> 01:26:47.000
That would be great.

01:26:47.000 --> 01:26:48.000
Alright, we have another chat question from zoe in.

01:26:48.000 --> 01:26:50.000
Thanks for the feedback as well.

01:26:50.000 --> 01:27:01.000
It's also about kamshaka and it's for ongo I'm curious if your experimentation with the source models gives you any intuition on how much near trench slip occurred.

01:27:01.000 --> 01:27:11.000
Slip near the trench was not something that the usgs model was particularly sensitive to. So i'm curious if you're a tsunami observations, provide any constraints.

01:27:11.000 --> 01:27:23.000
Ye i think. Ye thank you for the question. I think it's Definitely one of the main puzzles that we had with the 1st time we run the usgs model.

01:27:23.000 --> 01:27:29.000
And we have a delay and a. On one side, and then we have a early arrival on the other one.

01:27:29.000 --> 01:27:33.000
One of the discussions we had with the edwan with valley was that.

01:27:33.000 --> 01:27:41.000
Basically, the there's not a lot of land in the area where the missing sort of sleep was.

01:27:41.000 --> 01:27:52.000
And we believe that a lot of these inversions from uses might actually have some information from the land, and because there's no land to get more information than it could not.

01:27:52.000 --> 01:27:58.000
Retrieve that information only with the with relying on observations on land.

01:27:58.000 --> 01:28:02.000
Whereas luckily there was this one dart station that was.

01:28:02.000 --> 01:28:06.000
Giving the misfit. Further in the south.

01:28:06.000 --> 01:28:11.000
Southwest. That actually is the one that constrained the model in the end. So.

01:28:11.000 --> 01:28:15.000
我在questions that were like，if that will be。

01:28:15.000 --> 01:28:19.000
No longer needed, for in case of swat or something well.

01:28:19.000 --> 01:28:26.000
的depends on what。我们you are on the track。

01:28:26.000 --> 01:28:33.000
You might get the data in 3 days, 5, 8, depending where you are on earth.

01:28:33.000 --> 01:28:41.000
But that one, that that station is the one that in conjunction with the with the model and the other inversions is the one that actually.

01:28:41.000 --> 01:28:48.000
And i think. I don't know. How would you guess?

01:28:48.000 --> 01:28:51.000
That that was missing there with some other real.

01:28:51.000 --> 01:28:57.000
Data that that can support. That's right. I think that would be my coent on that one.

01:28:57.000 --> 01:28:58.000
I just like to follow, and then we'll go to bell. Let me but.

01:28:58.000 --> 01:29:01.000
对，对，对，对。

01:29:01.000 --> 01:29:09.000
We have a question from both angela and smer. Do you envision swad or other satellite data eventually helping the tsunami warning centers in real time, and.

01:29:09.000 --> 01:29:17.000
How, how much would it take to like. For that to happen. What changes need to happen.

01:29:17.000 --> 01:29:22.000
first, and then follow up.

01:29:22.000 --> 01:29:31.000
Okay, so i'll i'll do that. I i do think it's a it's a great tool, and it's definitely fantastic to be able to.

01:29:31.000 --> 01:29:36.000
To that. But from the time that. The other day i was looking at.

01:29:36.000 --> 01:29:42.000
How much data swot sense compared to starling other satellites, or something like that. And i think.

01:29:42.000 --> 01:29:52.000
This one was on the 3rd place of. The coercials or worldwide that are counicating to land that are open source.

01:29:52.000 --> 01:29:57.000
And it's just it's just an insane amount of data. What what it sends, i think, unless.

01:29:57.000 --> 01:30:03.000
I know that. One of the dangers is that what may be discontinued soon.

01:30:03.000 --> 01:30:07.000
Which is not a very good news. Hopefully. It's not gonna.

01:30:07.000 --> 01:30:14.000
Hopefully, he gets more support. But they are plan b and plan c for different type of satellites that are coming. That will.

01:30:14.000 --> 01:30:19.000
Covers similar for that, but i. I would guess that.

01:30:19.000 --> 01:30:25.000
For tsunamis that are in the entire pacific. Like in the like.

01:30:25.000 --> 01:30:27.000
我们的near fields。

01:30:27.000 --> 01:30:32.000
Is not a very good early warning. In the far field is a great warning. So in the near field.

01:30:32.000 --> 01:30:35.000
The warning is like, i will agree with whatever we.

01:30:35.000 --> 01:30:41.000
We heard here you feel an earthquake. You cannot stand, and you are near the coast. Just run.

01:30:41.000 --> 01:30:44.000
That's just what you have to do. I mean.

01:30:44.000 --> 01:30:53.000
And in the far field. I definitely think that's what our satellites they could. They could be a great tool for warning.

01:30:53.000 --> 01:31:00.000
Ye Certainly You can't beat having that much data about what the ocean is actually doing.

01:31:00.000 --> 01:31:06.000
you know, we start from pretty course forecasts as tsunami, warning centers, and.

01:31:06.000 --> 01:31:20.000
Then, as we get data observations, we're able to constrain those a lot better, and that's kind of the the turning point for us is, when do we have a dark, constrained forecast? And typically, we need 2 or 3 different darts to.

01:31:20.000 --> 01:31:24.000
Observe a full tsunami waveform before we get to that point which can take.

01:31:24.000 --> 01:31:32.000
An hour and a half, 2 h, depending on where the source is with respect to the dark constellation, and which darts are working at the time.

01:31:32.000 --> 01:31:38.000
And in this case. That dark, constrained forecast was really spot on so.

01:31:38.000 --> 01:31:44.000
We might not have gotten, you know, much additional improvement from using a swot.

01:31:44.000 --> 01:31:55.000
for this event, but. you know, swat would really shine with. We have more unusual sources that are pre-computed models, or a poor match for.

01:31:55.000 --> 01:32:02.000
Or if the the darts are mostly out near the source area, for a particular event. Things like that.

01:32:02.000 --> 01:32:08.000
you know, there's a lot of work to operationalize a new technique like this, but.

01:32:08.000 --> 01:32:16.000
it. It's certainly attractive down the road for us if if we can kind of speed things up.

01:32:16.000 --> 01:32:23.000
Thanks.

01:32:23.000 --> 01:32:30.000
Hi, my question is for jay and smer. I came up quite a bit in the chat, but it's very.

01:32:30.000 --> 01:32:40.000
clear from jay's map that, and it really makes sense to have some kind of a breakpoint in alerting. Basically at the mouth of san francisco bay, where every.

01:32:40.000 --> 01:32:50.000
The amplitudes really decrease significantly, and in smer's talk i believe she mentioned that there were some efforts to reduce alerting for some of the.

01:32:50.000 --> 01:32:58.000
more recent Sitting on me warnings, so i wondered if you could talk a little bit more about how that's being.

01:32:58.000 --> 01:33:04.000
Approached, and how it's going to be addressed in the future.

01:33:04.000 --> 01:33:08.000
I'm gonna let smer take the lead on this one.

01:33:08.000 --> 01:33:11.000
I i don't want to step on your toes, so.

01:33:11.000 --> 01:33:18.000
Sure and apologize the background noise because i am still in an operational center right now. So if you can hear that sorry.

01:33:18.000 --> 01:33:31.000
let's see where it even start here. We're trying to work with the weather service right now to produce different style, cap messages that would allow us to.

01:33:31.000 --> 01:33:36.000
kind of specify this tsunami alert zones differently in the future.

01:33:36.000 --> 01:33:43.000
that's 1 approach. talked about how we were changing, that we, a message itself.

01:33:43.000 --> 01:33:49.000
To be a little less specific about where the receiver is with respect to the hazard.

01:33:49.000 --> 01:33:56.000
That's another approach. We're in constant talks with our partners about.

01:33:56.000 --> 01:34:01.000
where breakpoints should be, and everyone wants more breakpoints and.

01:34:01.000 --> 01:34:11.000
things a little bit. You know. Less course. But The systems that the twcs have had over the last.

01:34:11.000 --> 01:34:17.000
Couple of decades have been in great need of upgrading and.

01:34:17.000 --> 01:34:24.000
That's what we're trying to do right now. Building systems that are a lot more agile, and can take partner requests into accounts.

01:34:24.000 --> 01:34:38.000
on a much more palatable timeline. so we're we're we're taking all those notes right now, and you know, similar to california's request for the bay area. We've got a request from washington for.

01:34:38.000 --> 01:34:49.000
Straight of wanda fuka, and we can have situations right now where that is a breakpoint, and we've got a different, alert, level for the canada side. As for the washington side, so.

01:34:49.000 --> 01:35:04.000
These are all well-known issues, and. We're. We're doing our best to find solutions that meet the needs of the partners, but they're always drawbacks to you know you've got to draw the lines on the map somewhere.

01:35:04.000 --> 01:35:12.000
And you know at some point you're going to step over a line and be in a different alert than the other side of the line. So it's all about trying to.

01:35:12.000 --> 01:35:17.000
Find the places where that's least impactful and and the best overall solution for everybody but.

01:35:17.000 --> 01:35:22.000
I am optimistic that we're closer to being able to do that.

01:35:22.000 --> 01:35:30.000
Ye and we and it sounds like that. We'll be able to add breakpoints once this new system is in place.

01:35:30.000 --> 01:35:34.000
And that might it might take a couple of years plus or minus to get that.

01:35:34.000 --> 01:35:43.000
to work. But ye i think that will. At some at that point we'll probably have. We'll need 2 breakpoints, one on either side of the golden gate.

01:35:43.000 --> 01:35:49.000
You know you sort of like need two breakpoints to be able to have a separate area. There.

01:35:49.000 --> 01:35:58.000
and then also. something that. So we the california tsunami program, so calus and cgs, we have.

01:35:58.000 --> 01:36:03.000
The california steering coittee, where we bring in cities and counties.

01:36:03.000 --> 01:36:09.000
And national weather, service, weather, forecast offices, and we invite.

01:36:09.000 --> 01:36:14.000
Smer, and dave from the ntwc. To participate in those meetings twice a year.

01:36:14.000 --> 01:36:25.000
And one of the things that we've been focusing on, especially after the kamchaka and the december 5th came into fall earthquake.

01:36:25.000 --> 01:36:32.000
Is, we've been strongly suggesting that. These the cities and counties.

01:36:32.000 --> 01:36:38.000
develop and advance some prescripted follow-on messaging that they can.

01:36:38.000 --> 01:36:43.000
You know, broadcast, after the the weia alerts have gone out.

01:36:43.000 --> 01:36:48.000
And so that is, you know, then they are.

01:36:48.000 --> 01:36:55.000
You know some of them are concerned about contradicting what the national the ntwc. Sends out so.

01:36:55.000 --> 01:36:59.000
They have to be very, you know. They have considerations.

01:36:59.000 --> 01:37:14.000
when in crafting those. But ye we got great news just today that the updated wheel language has been accepted and is going to be in place sometime, and maybe in the next month or so.

01:37:14.000 --> 01:37:19.000
Oh, and what was the other thing?

01:37:19.000 --> 01:37:28.000
Ye if i remember, i'll put in the chat.

01:37:28.000 --> 01:37:34.000
Thanks good question bill.

01:37:34.000 --> 01:37:38.000
let's see any other questions in the chat.

01:37:38.000 --> 01:37:45.000
Oh, okay, tyler asked. Are there specific seismic sources that define the 975 year event.

01:37:45.000 --> 01:37:54.000
so. North of so so i mentioned the development of the offshore hazard curve.

01:37:54.000 --> 01:38:02.000
And how we look for. specific sources that fit that hazard curve.

01:38:02.000 --> 01:38:08.000
In the in every location, and so north of cape mendocino.

01:38:08.000 --> 01:38:13.000
The sources for 9 75, the de aggregated sources for 9, 75.

01:38:13.000 --> 01:38:23.000
Our dot that's dominated by cascadia. And then south of cape mendocino. The night, the de aggregated sources for 9, 75.

01:38:23.000 --> 01:38:29.000
Are from the alaska seduction zone.

01:38:29.000 --> 01:38:33.000
Awesome. Thanks, jay. That's super interesting.

01:38:33.000 --> 01:38:43.000
i've got a question for nate So alameda kind of stood out in that i think it was 2017 paper of the over evacuation.

01:38:43.000 --> 01:38:54.000
is alameda only over evacuated in that chile case? Or does it always does it tend to always be over, evacuated.

01:38:54.000 --> 01:39:01.000
That's a good question, shawn, and i will. And we'll start off by saying like, this is a term i started, you know, out with, but like.

01:39:01.000 --> 01:39:06.000
Over evacuate is kind of. Value, laden so like.

01:39:06.000 --> 01:39:09.000
We'll put that. We'll just leave it at that.

01:39:09.000 --> 01:39:15.000
But in general i think that the the the potential for having more people that.

01:39:15.000 --> 01:39:20.000
May not be impacted. It's definitely possible for every tsunami, because.

01:39:20.000 --> 01:39:25.000
You know, and that's what jay was mentioning earlier about their faster, which is an acronym.

01:39:25.000 --> 01:39:29.000
To kind of have stage levels of. Hey? You're in a phase, one or a stage one, and you're in a stage 2.

01:39:29.000 --> 01:39:34.000
but a tsunami zone, especially a probabilistic, is like.

01:39:34.000 --> 01:39:39.000
Every tsunami on the pacific basin. This is kind of where we think there would could be water from.

01:39:39.000 --> 01:39:48.000
But that doesn't happen with every unique scenario or every event like it's just from chile. It's just from alaska. It's just from japan, or just from russia.

01:39:48.000 --> 01:40:01.000
So every place has that potential and to arm wave a little bit, you know, with the chilean event we were seeing massive differences between the max zone and the.

01:40:01.000 --> 01:40:11.000
the chilean related foundation from an alaskan event. It might be something where, or a cascading event. You would see the opposite like, if you're in southern coast, like.

01:40:11.000 --> 01:40:17.000
Coronado, san diego. The max zone, might be more reflecting. Something in japan.

01:40:17.000 --> 01:40:21.000
Or somewhere west in the pacific, and so a cascadia event.

01:40:21.000 --> 01:40:28.000
Is probably not going to likely not to inundate as much as something coming from a whole totally different direction. So.

01:40:28.000 --> 01:40:40.000
Direction really matters and how much time they have, and how far they have to get to save to you really matters. So ye i'm not picking on alameda. We just did a paper there for bay farm, and we did a paper.

01:40:40.000 --> 01:40:46.000
For balboa down on the south coast, and that potential is everywhere.

01:40:46.000 --> 01:40:50.000
which is why, having like a faster again, an acronym, faster approach.

01:40:50.000 --> 01:40:56.000
To say, this is from coming from chile. This speech is in a stage one, whereas.

01:40:56.000 --> 01:40:59.000
8 counties over, you might be in a phase 4.

01:40:59.000 --> 01:41:07.000
I think that's to me. That's pretty important for, and not just california. Every state i mean. Hawaii city is always the proverbial bullseye.

01:41:07.000 --> 01:41:12.000
But where it's coming from matters greatly whether you get tons of inundation, and conan, big island.

01:41:12.000 --> 01:41:20.000
Where you get inundation up in honolulu, like. Location and time matter hugely, and and the tsunami realm.

01:41:20.000 --> 01:41:21.000
Hugely. I'll say it's probably not a word.

01:41:21.000 --> 01:41:27.000
Thanks, ye no super interesting to me. Just cause, you know, there's.

01:41:27.000 --> 01:41:35.000
A pretty good historical record there, and i don't recall anything big and alameda, and of course that's why you're doing the probabilistic thing. You don't want to just rely on that. But Ye that's pretty interesting.

01:41:35.000 --> 01:41:42.000
Right book. That paper that well, the the national, the state level paper, looking at chile versus.

01:41:42.000 --> 01:41:50.000
The the max zone. I couldn't get into it, but it, you know, gets into like how much money is being spent by american red cross to open up shelters that.

01:41:50.000 --> 01:41:56.000
No one needs to go. How much money is being spent by that family that has to go inland for 12 h.

01:41:56.000 --> 01:42:03.000
2 days. Maybe they got a hotel. You know, because they're they were told they should have looked at. They'd evacuated, and then they're spending money on hotels and.

01:42:03.000 --> 01:42:11.000
And food at the diners. All the law enforcement that's gonna be pushed out the door to help navigate something. So there's a lot of, and then.

01:42:11.000 --> 01:42:15.000
Just the economic impacts. I think it was like 220 million.

01:42:15.000 --> 01:42:25.000
Dollars lost per like 4 h For, you know, because people stop warouses. You leave the restaurant all of a sudden, and maybe don't come back.

01:42:25.000 --> 01:42:29.000
so there's a lot of lost expenditures for manufacturing retail.

01:42:29.000 --> 01:42:35.000
but i don't really captured. If if the goal is, we're hay saving as many lives as we can, that's great.

01:42:35.000 --> 01:42:46.000
But there are definitely disruptions to the economic and the social system to do that, to have that as your leading assption.

01:42:46.000 --> 01:42:55.000
啊i had a question for。啊pat about stratification on the water coln，and i love it when speakers ask each other questions。

01:42:55.000 --> 01:43:04.000
Ye Ye No, i i answered it, for in the in the chat, but it it's a it's a shallow harbor. There's There's a diurnal.

01:43:04.000 --> 01:43:10.000
Temperature, variation, but vertical. It's pretty weak, so you wouldn't expect it to be able to sustain.

01:43:10.000 --> 01:43:17.000
Any sort of sheer-induced. Mixing on that interface. It's a few degrees.

01:43:17.000 --> 01:43:23.000
Nick, you want to ask your question out loud.

01:43:23.000 --> 01:43:33.000
Sure. Why not hey, everyone. I was curious to ask the panel. How does c-level rise and fluent tsunami hazard.

01:43:33.000 --> 01:43:43.000
Well, that's a great question. And We we just finished 18 month study on that working with pat lynette yourself.

01:43:43.000 --> 01:43:53.000
call louis to do some hasus analysis. And the and of some fema contractors, doug, doug, bauish and and ashley.

01:43:53.000 --> 01:44:05.000
And oh, gosh, oh, i can't believe him. I have a brain far on his name, and then and so we did hazis. And then we did. Esri infographics risk analysis to to look at that.

01:44:05.000 --> 01:44:19.000
So we've got. It's coming out in the 5th climate change assessment report later this year. It was just approved by the editors. It was the first.st Paper to be approved.

01:44:19.000 --> 01:44:26.000
And so we have about 500 pages in that in those reports, because we did so many different things. But we basically looked at.

01:44:26.000 --> 01:44:34.000
between 103,000 year arps, and we looked at 0 point 1 half one and 2 meters of sea level rise.

01:44:34.000 --> 01:44:42.000
And one of the interesting outcomes that. Pat figured out is that.

01:44:42.000 --> 01:44:49.000
The the main damage to harbors. So we did some harbor analysis.

01:44:49.000 --> 01:44:53.000
Looking at the fragility of harbors. Is that the mean.

01:44:53.000 --> 01:44:58.000
Hazard, or the mean damage to hat, to, to harbors.

01:44:58.000 --> 01:45:08.000
Was pretty flat line, but that the that the as the as with the sea level with greater sea level, rise the variation in the damage.

01:45:08.000 --> 01:45:20.000
Was larger. And so with that heightened, highlighted is that that we need to do site specific analysis to really take a look to really understand what the impact of sea level rises.

01:45:20.000 --> 01:45:30.000
On tsunamis. So i think that's probably one of our biggest outcomes.

01:45:30.000 --> 01:45:31.000
Oh, i have. I have. I have lots, but i think we're at a time.

01:45:31.000 --> 01:45:32.000
Pat. Do you have anything else to add.

01:45:32.000 --> 01:45:33.000
I think i think. Ye right out of the time. Thanks, matt.

01:45:33.000 --> 01:45:35.000
Alright.

01:45:35.000 --> 01:45:40.000
Alright great discussion. Everyone. That's. Thanks for all the questions and answers.

01:45:40.000 --> 01:45:42.000
Ye thanks for all the great talks.

01:45:42.000 --> 01:45:46.000
This was wonderful. Thank you, to all of our great speakers.

01:45:46.000 --> 01:45:53.000
Thank you to all wonderful moderators, an extra big hand for international speaker ongo for staying up so late. Let's let him go to sleep and or go outside to enjoy the aurora boy. Alice.

01:45:53.000 --> 01:45:57.000
Take your content. So john.

01:45:57.000 --> 01:46:02.000
And now let's take a quick break. Of no more than 15 min. Come back sooner, if you can, so that we can get to our final amazing session. As soon as we wake up.

01:46:02.000 --> 01:46:14.000
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