Advances in Tsunami Warning Systems Since the Great...

LirneAsia Disaster Risk Reduction Lecture, June 19, 2014

Advances in Tsunami Warning Systems

Since the Great Sumatra Earthquake of 2004

Presented by Dr. Stuart A. Weinstein, Asst. Director

Really Cool Graphics by Dr. Nathan C. Becker

Most Awesome Simulation by Dr. Dailin Wang

All At: NOAA/NWS/PTWC


Earthquake Tsunami

Tsunami Warning Center

International

- Regional

FrameworkNational Warning System Public Awareness

National Government

Local Government

People

Mass Media

Where is

Evacuation

Route?

What is

Tsunami?

TSUNAMI Warning System

Thanks to Cabinet Office Japan


A Tsunami Warning System Has

3 Main Components

1. The Tsunami Warning Centers=>Detect Earthquakes and evaluate tsunami potential, look

for sea-level changes and issue message products. (manage technology, information)



3 Main Components

2. Disaster Management Organizations=>Develop evacuation plans, communication systems,

receive warning center message products and make decisions.



3 Main Components

3. Education of Citizens in Areas With Tsunami Hazard Risk=>Public should know what to do in the event of a tsunami

emergency.

PUBLIC

OUTREACH


TSUNAMI WARNING AND

MITIGATION SYSTEM

An EFFECTIVE system means:

All persons in vulnerable coastal communities

are prepared to respond appropriately, and

in a timelymanner upon recognition*

that a potentially destructive tsunami

may be approaching.

*Recognition Means Understanding natural signs like the

ocean drawdown or sustained, strong ground shaking as

well as what to do when the sirens sound.


• VERY RAPID

EARTHQUAKE EVAL

• VERY RAPID TSUNAMI

SEA LEVEL EVAL

• VERY RELIABLE

COMMUNICATIONS

e.g., Multi-national,

global data networks

with real-time transmission

and free/open data sharing

ALL REQUIRED FOR

TIMELY WARNING IOC GLOSS Network, incl real-time, non-real time, archive

For Tsunami Warning - 3 Basic Needs


Sumatra Earthquake Dec. 26, 2004

Mw = 9.2!

3rd

largest recorded

Rupture Length

~ 1200km

Rupture propagated

South To North for 550s

Great Chile Earthquake

of 1960 took ~300s

=> Generated Basin Wide

Destructive Tsunami that

killed > 275,000 people


Sumatra Earthquake Dec. 26 2004PTWC TIMELINE (GMT)

00:59 Sumatra EQ Starts

01:07 PTWC Duty Scientists

paged by digital alarm

01:08 Sumatra EQ Stops

01:09 PTWC has location

01:14 PTWC issues TIB

with Mw=8.0

02:04 TIB issued with

Revised magnitude 8.5

No Tide Gauges in Region

05:00 Wire reports of deaths

In Thailand and Sri Lanka


What went wrong on Dec 26, 2004?

Well, pretty much everything.

1. No Tsunami Warning System!

2. Sparse Seismic Network.

3. No real-time Sea-level Data.

4. Science wasn’t good enough!


So what went wrong on Dec 26, 2004?


1. No Tsunami Warning System

NDMO SOPs not developed.

No Reliable method to alert the

public. Could not traverse “last mile”

No public awareness.




2. Sparse Seismic Network

Took too long to detect, locate

and size up Earthquake.




3. No real-time Sea-level Data

PTWC did not understand scope of

tsunami impact until reading press

releases on the internet.




4. Science wasn’t good enough!

Took three weeks to understand just

how big the Sumatra Earthquake was.

No Real-Time Tsunami Forecasting




5. No real-time Tsunami Forecast

Could not properly gauge how

destructive tsunami would be 1000’s km

away from Sumatra within first 240 min.


So what has changed since

Dec 26, 2004?



Tsunami Warning Systems World-Wide

Most Coastlines Covered Today!

Core Seismic Network - PTWC

1999 2005

In 2014, PTWC

receiving data

from > 600 stations

in real time

2012

Core Sea Level Network - PTWC

1999 2005

In 2014, PTWC

receiving data

from > 500 stations

(coastal, deep-

ocean) in real time2012 Coastal Stations DARTs


Downloaded at Wallops Island

VA/USA and forwarded to the

US TWCs and Met. Offices.

Hiva Oa

CHANNEL 32

GOESW

Part of the GTS

Coastal Sea-Level Stations:1. Situated in shallow water

2. Typically installed along piers.

3. Usually first to detect tsunami

4. Provide “facts on the ground”


DEEP OCEAN, REAL TIME

TSUNAMI REPORTING SYSTEMThe tsunami signal is

detected by a pressure

sensor on the ocean

floor. That signal is

relayed by acoustic

telemetry to the buoy.

The buoy in turn

transmits the signal

via satellite back to

the warning centers.

Can measure changes

in sea-level as small

as 1mm!

DART Buoy

Deep Water

5000m

Potential Epicenters of Tsunami Generating Earthquakes

Epicenters spaced ~120km apart


The CMT characterizes the geometry of the earthquake and can be used to compute the surface deformation.

Fits shape and amplitude of seismic waves to synthetics to model moment tensor and energy released.

Usually based on longer period and very slow surface waves. CMT required ~90 minutes of wait until there was enough data to compute.

Centroid Moment Tensor (CMT)

Strike-Slip

Pure horizontal

motion

Thrust

Pure Vertical Motion

Oblique, motion

has horizontal and

vertical components


Problem with using CMT for tsunami hazard:

=> It took too long.

That changed with the introduction of the W-phase CMT by Kanamori and Rivera in 2008. W-phase travels several times faster than surface waves.

W-phase CMT method gives both the fault geometry and an authoritative magnitude 20-25 minutes after the earthquake. It is the primary reason why PTWC can now quickly issue a reliable forecast.

Centroid Moment Tensor (CMT)

Strike-Slip

Pure horizontal

motion

Thrust

Pure Vertical Motion

Oblique, motion

has horizontal and

vertical components


CMT via Wphase

Inversion

Japan 2011,

Mw=9.1

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-----####### T ########------------

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---################-------- P ---

---##############--------- --

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08:52Z

09:17Z

10:16Z

Great Sumatra Earthquake Apr. 11, 2012

C. Best Agreement with

Tsunami measurements.

Mw 8.7

Mw 8.8

Mw 8.6


April 11, 2012 Sumatra Tsunami (Mw=8.6)

Forecasts vs. Observations

Thrust and too big

Strike Slip

Oblique

Tsunami Warning < 3 hrs, Watch 3 – 6 hrs from arrival

Status based on time until wave arrival

Status based on time until wave arrival

Tsunami Warning < 3 hrs, Watch 3 – 6 hrs from arrival


Real-Time Tsunami Forecasting

This forecast took just

A few seconds to create!

Red and Orange Correspond to

Areas in a Warning

The forecast would place much

less coastline in a warning

status then a determination

based on time to wave arrival.

Thousands of kms of coastline

are spared being placed in a

warning.


The Past Ten Years Have Witnessed:

1. The proliferation of Tsunami warning systems.

2. A tremendous increase in Seismic and

Sea-Level Monitoring Networks

3. Scientific progress in determining earthquake

characteristics and Tsunami forecasting.

Anything else?

6th CAP Workshop, Negombo Sri Lanka, June 19, 2014

Message Pathways

AFTNairports

AFTNairports

GTS/NMCinternational

GTS/NMCinternational

NWWUSA & Canada

NWWUSA & Canada

IDNHawaii

IDNHawaii

HAWASHawaii

HAWASHawaii

NAWASUSA & Canada

NAWASUSA & Canada

Telephonewarning points

Telephonewarning points

FAXwarning points

FAXwarning points

Websiteanyone

Websiteanyone

Emailanyone

Emailanyone

RSS Feedsanyone

RSS Feedsanyone

EMWINwarning points

EMWINwarning points

SMSRANET

SMSRANET

Text

Phone

Internet

Sate

llit

e

CAPCAP


The Rise of Social Media and Personal

Communication Devices

CAP (Common Alert Protocol)

Facebook

Twitter

Youtube

All of these Applications help to extend the reach

Of Emergency Management Agencies.


PTWC Twitter Page


PTWC YouTube Page


CAP

CAP can easily drive geographically aware alerting systems:

• IPAWS/WEA from FEMA

• Google Public Alerts

And other systems that are fast, robust, and viral:

• SMS text messaging

• Social media (twitter, facebook)

• Citizen-led initiatives such as #hitsunami


Questions

?

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