TB 144 - Tsunami Flashcards
According to TB 144 tsunamis can reach speeds of how fast?
600 mph
In terms of consequence and frequency, TB 144 characterizes Tsunamis to be a what kind of risk?
Low frequency, high consequence events
Tsunamis are classified as local or distant. Local tsunamis are considered rare, however Travel time for a local tsunami is what?
5 to 30 minutes
Tsunamis of a distant origin are said to reach coasts in what time frame?
5 1/2hrs to 18 hrs
What 3 battalions are included in the predicted “worst case scenario” mapping for Lafd?
Battalions 3, 6 , 9
How many centers are there for alert and notifications of tsunamis? Where are they located?
2 centers
WC/ATWC = west coast/Alaska Tsunami Warning center (palmer, Alaska)
Hawaii based pacific tsunami warning center (Honolulu)
The 2 centers for alert and notifications of tsunamis are known as
WC/ATWC and the pacific Tsunami Warning center, they are warning systems for what type of tsunami, local or distant?
Effective of distant tsunamis only
California is vulnerable to what type of tsunamis? Local or distant?
Local - current warning system does not fully meet Californias needs.
According to TB 144 an earthquake felt along the coastal areas of the city lasting longer than how many seconds should be considered a warning sign ?
20 seconds
According to TB 144 what might be the first visible indication of an approaching local tsunami?
The recession of water
The WC/ATWC updates messages how often during an alert?
30min
How many types of tsunami alerts are there?
7 types - warning, watch, advisory, information bulletin, information message, cancellation, communication test.
Tsunami warning - explain it, break it down
Highest level - size of quake 7.1 - 7.5 : warning issued of 217.5 miles (350km) on either side of epicenter
7.5 or greater - issued within 3hr tsunami travel time zone
Tsunami advisory - what is it, break it down
Issues this type of advisory for an event outside its area of responsibility or threat. Basically just advising to monitor the situation but a tsunami advisory is OUTSIDE the area of threat, outside of the areas for warning or watch.
Tsunami watch - what is it, break it down
It’s the second highest level of alert.
Given to areas outside of the “warning” areas.
7.5 or greater watches are sent to areas within a 3 -6 hour tsunami travel time zone.
Tsunami information bulletins - what are they, break it down
Information bulletins are issued to participants to advise them on activity and basically evaluating the situation on 3 levels
- Earthquake happened no danger as of now
- That a tsunami Capable of causing destruction beyond local area has been generated
- There is a probability of a tsunami and to advise that a tsunami investigation is underway
Tsunami information message - what is it, break it down
Information messages are when smaller earthquakes occur (less than the warning threshold) and are felt, main objective is to assure residents that there is no tsunami threat and that they are aware of the small event
Tsunami alert cancellation - what is it, break it down
Will be sent when danger of tsunami has passed. Some strong currents may still be present
Tsunami communication test - what is it, break it down
The WC/ATWC issues unannounced test messages on a monthly basis to determine delays of the information getting out.
In the event of a local tsunami, according to TB 144 which wave will be the largest wave?
The first wave will be the largest
Who is responsible for notifying LAFD about all tsunami warning, watches and advisories? Who is the predetermined point of contact for these notifications?
LAcoFD is responsible for notifying LAFD via Metro as their point of contact
Tsunami timeline - TB 144 breaks down a timeline for tsunami arrivals. What are the 3 time groups?
0-4 hrs
4-8 hrs
8hrs or more
How many levels are there for LAFDs Tsunami modes?
Level 1 -3 : level 3 being the highest/most severe
During activation of level III tsunami mode all fireboats will go out to sea to a minimum of what depth?
1000 feet minimum
What is the highest level of tsunami alert? This alert is activated for magnitudes from _____to ______ and issued to areas within ______miles/km to either side of the epicenter. If earthquake is greater than ______magnitude alerts are given to areas within a 3 hr tsunami travel time zone.
Highest level is Tsunami Warning
7.1 - 7.5 , 217.5miles/300km
Greater than 7.5
Tsunami Watch is the second highest alert level. For earthquake magnitudes greater than 7.5, a Tsunami Watch is issued to areas within a _____to _____hour tsunami travel-time zone
3 to 6 hour tsunami travel time zone
Tsunami information message is issued when?
These messages are issued when an earthquake occurs but is less than the threshold for issuing a higher alert, less than 7.1. Basically these messages just inform the jurisdictions that they are aware of the earth quake and they do not foresee any threat.
Who issues the tsunami alert cancellation, the WC/ATWC or local management officials?
The local management officials due to the complexity in local environments
Tsunami communication tests are conducted, daily, weekly, monthly, quarterly or annually ?
Monthly
True or false .
tsunami waves from a distant source, often come as a series of waves, with the first wave not always being the largest and local tsunamis, the first wave will be the largest.
True
True or False
It is the responsibility of the Los Angeles County Fire Department (LACoFD) to provide immediate notification to the LAFD of all tsunami watches, warnings and advisories affecting the coastal areas of the City of Los Angeles. Operations Control Dispatch (MFC) is the pre-determined point of contact for the LAFD.
True
Upon activation of level 3 tsunami warning all fireboats shall go to sea exiting at LA harbor Light, strike a heading of ______for _____miles to a depth of ______
210 degrees for 3.2 miles
1000 feet
This rendezvous point is within the USCG recommended tsunami evacuation guideline of 600 to 1200’
According to TB 144 - Normal tidal shifts in the LA Harbor can range from _____to _____ feet, leaving Department fire boats with as little as _____feet of clearance from the harbor floor during low tide.
7 to 11 feet
2 feet
In general, after receipt of a Tsunami Warning, agencies can assume all-clear status when their area is free from damaging waves, strong currents and extreme tidal changes for _____ hours, unless the WC/ATWC has announced additional ETA’s, or local conditions warrant continuation of the Tsunami Warning status
2 hours
True or false
LAFD fire boats shall not re-enter the LA Harbor until given the “All Clear” from the Battalion 6 Commander.
True
Tsunami timeline coincides with tsunami modes, level 1, 2 , 3.
Level 3 is the highest most severe level.
What are the 3 timeline breakdowns?
0 - 4 hrs
4 - 8 hrs
8 + hrs
Tsunami timeline coincides with tsunami modes/levels
What are the modes/levels?
Level 3 highest
Level 2
Level 1
With a level/mode 3 tsunami alert, all fireboats will go to a minimum depth of what?
When exiting the harbor at LA light, take a heading of _____true north for _____miles.
1000 feet
210 degrees
3.2 miles
According the the tsunami TB, LA Harbor tides can range from ___to____leaving the fire boats with as little as ____feet clearance.
7 to 11 feet
2 feet
