Communications Academy 2012
Preparing for Future Volcanic Eruptions - Mt. St. Helens Lessons Learned
Carolyn Driedger
U.S. Geological Survey, Cascades Volcano Observatory April 15, 2011
When Mount St. Helens erupted in May, 1980, we made the most of it... ;
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Contents of this talk
ide zard
ation
Helens Mount St. Helens 1980 to Monitoring present. Restless
Volcanoes
Evidence of active volcanism Multiple hazards
Economic impacts Recommendations for preparation.
Let’s take a closer look. Mount St. Helens 1980
eLack of eruption pre-planning and experience with large eruptions.
ePublic (and officials) unaware of eruption potential in Cascades.
eEruption legacy in science, eruption response, preparedness and recovery (pre- dated coordinated inter-organizational responses)
Timeline: Pre-May 18, 1980 Eruption
1978: USGS-MSH hazard assessment; states eruption Is likely within 100 years, “perhaps before the end of the century”
3/20/80: First significant earthquakes 03/25: First exclusion zones
03/25: TFR in place
03/27: First ash explosion
04/03: State emergency declaration 05/17: Some cabin owners escorted to Spirit Lake; others planned for 5/18 05/18: Eruption at 8:32 a.m.
USGS, 5/17/1980
Timeline: May 18, 1980
Eruption at 08:32 a.m.
¢ North flank landslide and lateral blast devastate 600 km? (230 mi2)
¢ Eruption column to 20 km (12.5 mi) in <10 min
¢ Eruption lightning starts hundreds of small forest fires
¢ Ash causes darkness to east for >650 km (400 mi)
¢ Lahars extend ~ 130 km (80 mi)
Timeline: post May 18, 1980
5 smaller explosive events through October 1980
Episodic ERUPTIONS! Lava dome growth from October 1980 to October 1986
1989-1991: 22 seismic swarms and 6 ash explosions
Increased sedimentation in Toutle River still an issue (2011)
USGS, 1980
Physical and Human Effects
9/7 fatalities — About 200 homes destroyed by lahars _ ~~
Extensive damage to land and infrastructure
—- devastation of 600 km2 of forest - bridges, roads, railways
—- sewage disposal/water supply re usGel so * - loss of Spirit Lake recreational area
Ash severely affects southern Washington to Montana
Economic Impacts
Estimate: (1980 $) — $1-2B ¢ $450M timber destroyed ¢ $40-100M agricultural damage e >$100M infrastructure damage
e $1B- water transportation and mitigation
e Ash cleanup costs—total unknown oe
ec aZUSGS
Lessons Learned from 1980 events
Long-duration events quickly deplete resources and patience
Recovery can be slow.
Public officials need to make safety decisions before outcomes are known
Interagency planning essential
Hazards persist long after a large eruption ends
Volcano monitoring is critical
Progress in 30 years
USGS-CVO observatory established
Research about eruption potential at OTHER Cascade volcanoes.
Interagency response plans created for most WA and OR volcanoes
National Incident Management System - a tested approach
A much more informed public
Challenge is more people living close to active volcanoes. The most recent disaster fades from memory before the next strikes.
What happened after 1980?
1980-86: MSH eruption: eruption story spreads globally 1980s-2004: Update of monitoring, hazard assessment, and coordination plans throughout Cascades, but especially at MSH 1989-1991: 22 earthquake episodes, 6 with explosions
2003-04: Quietest seismic period since 1980
2004 First Sign of Unrest: Earthquakes
9/23: earthquake swarm (similar past swarms did not result in eruption) 9/24-9/25: hundreds of earthquakes, then decline
9/24: release of Information Statement triggers call down, initiation of meetings between federal, state and local officials
9/26: uptick in energy release prompts Notice of Volcanic Unrest
Alert Level Changes Draw Notice
Uptick in activity leads to major response; high uncertainty
9/27: media tsunami at CVO; high demand on scientists’ time 9/28: deformation of crater ice confirmed
9/29: 3 to 4 earthquakes per minute; alert level raised to Volcano Advisory 10/1: first steam and ash eruption; plume rose to ~12,000 feet
10/2: volcanic tremor prompts Notice of Volcanic Alert; Interior Secretary Gayle Norton visits CVO
10/3: Joint Information Center opens 10/2-10/5: more steam eruptions thrill observers
An Eruption in Real Time Explosion viewed by millions, Oct. 1,2004
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October 4, 2004
2004-2008 Slow extrusion of lava formed a ‘lava dome’
sof Mount St Helen os ~200/ 2006
Unified Command & Joint Operations Center (JOC):
Joint Operations Center in operation for two weeks. Joint Information Center located away from media crowds (800 requests in 11 days) Cost USFS $95K
—- no declaration of emergency
meant no reimbursement to USFS and local agencies
The Joint Information Center (JIC) served many functions
¢ Media Monitoring ¢ Rumor control ¢ Tracking JIC messages
¢ News releases ¢ Talking points
¢ Source for media and ¢ JIC chronology
public inquiries
Activity Level vs. Public Interest
—_-_ —_- —_- —_— (— an er aoa nN ow —
eUSFS webcam: 36 million hits 9/24 & 10/5 “USGS site: 55,000 to 1.43 million hits daily
eInternet capabilities of both exceeded
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Five lessons to apply:
V Cascade volcanoes are ‘active’ and functioning volcanoes doing what volcanoes normally do. Your volcano will erupt again. There will be a short period or warning. Multiple hazards and long-term uncertainties.
Economic impacts can last for decades.
There is demonstrated value in inter-agency preparation— anticipating needs, developing and practicing response plans, volcano monitoring, education.
_ Cascade volcanoes are active, functioning volcanoes.
Long periods of quiet punctuated by eruptions
EVIDENCE: eActive hydrothermal systems
eActive seismicity (earthquakes)
eRecentness of eruptions ~ North Zé erican Plate
ZSVolcanoes « Earthquakes
eLocation at Cascadia subduction zone with active magma generation.
Modified from Yelin and others, 1994
Your volcano will erupt again
Eruptions in the Cascade Range During the Past 4,000 Years
Mount Baker
Glacier Peak
Mount Rainier
Mount St.Helens ~~~ Mount Adams
Mount Hood
Mount Jefferson
Three Sisters Newberry Volcano Crater Lake
Medicine Lake Volcano Mount Shasta
Lassen Peak
California
2,000 Years Ago Ee Eruption or period of multiple eruptions at or near named volcano
ll erupt again
Your volcano w
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Your volcano will erupt again, but you will be warned
As magma moves to the surface:
- lt breaks a pathway
¢ It releases gases
¢ The chamber or conduit may increase or decrease in volume
These processes result in effects that we can measure:
¢ Earthquakes
¢ Emission of magmatic gases, principally CO, and S gases
¢ Ground deformation
Surface deformation
Lava dome
Taleleime)i magma
Seismicity
:
You will be warned
Tilt, Strain,
Temperature
Mudflows Rainfall
Deformation
USGS mandate is to provide warning
USGS alert-level system focuses on the state of the volcano with an emphasis on ash for the aviation community
Alert level Aviation Color Code
TERM DESCRIPTION COLOR DESCRIPTION
NORMAL Typical background, non-eruptive state
ADVISORY Elevated unrest above known background activity
Heightened/escalating unrest with increased potential for eruptive activity. timeframe variable, OR, minor eruption underway
that poses limited hazards
Highly hazardous eruption underway WARNING or imminent
USGS
You will be warned
IMAGES HAZARDS
Latest U.S. Volcano Alerts and Updates for Thursday, Oct 28, 2010 at 14:48:41 PDT“
Cieveland Advisory Yellow Kilauea Watch Orange Long Valley Volcanic Center Normal Green Cascade Range Normal Green Pagan Advisory Yellow Sarigan Unassigned Unassigned Anatahan Normal Green Mauna Loa Normal Green Yellowstone Normal Green Explanation of alert levels and color codes
Features
Websites: http://volcanoes.usgs.gov
PUBLICATIONS
OBSERVATORIES
Scientific information:
e USGS and PNSN for volcanic activity
eUSGS for warning - Alert Level System
e USGS and NWS for ash fall and lahar warnings
Response Information e NIMS/ Unified Command
e Interagency response plans
Public information e Media e Social media
Warnings will not be B&W
The 1980s eruption was about 5 times larger than the 2004 to 2008 eruption; largest MSH event about 6 to 8 times larger than the 1980-86 event.
EMs will need to make decisions long before outcomes are known
_- “Decision window” for public officials
Shape, character, duration very irregular
Build-up suggests eruption is likely
Cannot guarantee that eruption will not occur
Intensity of monitoring parameters
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EMs will need to make decisions long before outcomes are known
Decision rs window for ehfier 5 Sas eG Eruption 3 p 7 officials = © © foe oy) < 9 (e fe) = Oo ran € ® Serr Back to (FS
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Time —~ ZUSGS
~ Multiple Volcano hazards and long-term uncertainties
Volcanic events can last for weeks, months, decades
Hazardous Warning Event Duration : Event Weeks to Days Days Weeks to Months months to years
months Flood
Hurricane
Earthquake /tsunami Wildfire
Eruption
Multiple Volcano hazards
Proximal areas ( $15 mi) subject
: 55 i to multiple lethal hazards: ee Eruption Cloud
Eruption Column
: Tephra (Ash) Fall Intermediate areas (> 15 <100) ae
Lahars, tephra fall and floods affect L river valleys:
¢ Distal hazards (>100 mi) - Tephra fall affects areas downwind:
Excess sediment in watersheds reduces flood capacity:
Lahar hazards
¢Know which volcanoes are up valley of your community.
eAsk scientists where the most likely vent area will be and what rivers it might affect
¢Have a plan to deal with reservoirs on potentially affected rivers
EXPLANATION Ba Debris flow hazard zone
CJ Lahar hazard zone
Post-lahar sedimentation zone in Green-Duwamish valley
- Cc] Lava flow and pyroclastic flow hazard zone
| 0 5 10 Kilometers |
Lahar at Semuru volcano, Indonesia Video by Franck LaVigne
Lahar hazards
Hazards can persist long after an eruption Is over
Fill tevel 2 yr after eruption
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Lahar hazards
Hazards can persist long after an eruption is over
Bridge crossing immediately affected by the eruption; months later
Some communities in the Philippines were not affected until years to a decade after the eruption
Volcanic Ash
e Particles of shattered rock.
e Falls at normal air temperature at distance from the volcano.
e Non poisonous to touch or breathe.
e lrritates eyes, breathing difficult, reduces visibility, abrasive, clogs filters.
Tephra (ash) hazards
MOUNT\(— 98509) or eel — ‘ag
} Portland
OREGON IDAHO
300 KILOMETERS
200 MILES
Pdcatello : _ 1816+
Figure 341.—Isochron and isomass maps compared. Black lines, isomass of fallen-ash lobe: and red dashed lines, trol. Time in PDT. See figures 332, 338, and text
isochrons of airborne-ash plume; red lines, inferred positions of isomass lines extended beyond area of con- for further explanation.
aZUSGS
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Radio, TV and Telephone Communications...
...are extremely vulnerable to disruption during volcanic ash fall and may fail completely in eruption-effected areas.
However, there are many examples of
functional communication during ash fall.
ZUSGS
Impacts of Volcanic Ash on Communications
e Disruption of signal during eruptions
e Overloading of telephone/computer communication systems.
e Disruption of electrical supplies
e Cooling systems challenged
e Electrical shorting of equipment e Long-term abrasion of equipment
ZUSGS
Examples of Communication System Overloads
e Overloaded Telephone Systems — Mount St. Helens 1980 — Mount Spurr Alaska 1953, 1992 — Mount Ruapehu NZ 1995-96
e Overloaded Internet Systems — Mount Ruapehu NZ 1995-96 — Nisqually Earthquake 2001
ZUSGS
Examples of Signal D1
e Katmai Alaska 1912—Radio communications inoperative.
Surtsey, Iceland 1963—Clicks of radio static common.
Pinatubo, Philippines 1991— Disruption of radio and telephone communications.
ZUSGS
Mitigation Measures Communication Systems
¢ Seal facilities including Repeater Stations — Shut air intakes
— Use internal air circulation — Seal all equipment that is not already watertight.
ZUSGS
Mitigation Measures Communication Systems
¢ Remove Ash from external electrical systems and from /insulators/antennae/
microwave dishes.
— Shut down electrical systems and vacuum, dust, and blow ash from electrical equipment.
— Replace Teflon with ceramic insulators.
— Install covers; plastic tarps work well in emergency.
Mitigation Measures Communication Systems
¢ Factors affecting electrical flashover 14
— Weather conditions (high air moisture content increases ash adherence).
— Presence of electro-static charge.
— Grain size and ash fall thickness.
— Soluble components on ash (conductivity).
— Insulator condition and orientation.
Mitigation Measures 4 Communication Systen<
e Further Cleanup
— Plastic switches abrade quickly; Replace.
— Clean equipment daily with =-"a 3
compressed air or vacuum. ~~ — Keep moisture out of Be as ecicidelog i
~ is
Mitigation Measures Communication Systems
e Practical Advice e Protect yourself and others.
e Recognize potential for ash fall locally.
e Assemble items required for
sealing facilities and for
cleaning equipment.
Maintain backup electrical and
communication systems.
ZUSGS
Most serious issues
e Most serious problems result from the conductive and abrasive properties of ash.
e Ash may be resuspended by human activity for months after an eruption.
e Expect disruptions of signals, overloading of telephone/computer communication systems, and of electrical power, electrical shorting of equipment, abrasion of equipment.
e Most effective measure is to reduce input of ash into systems.
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a USGS
Tephra (ash) hazards
Tephra affects aviation, which may impede recovery efforts
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¢ ~2000 flights over the Cascades daily
¢e Ash can reach cruise altitudes in a matter of minutes
How would reduced aviation affect your recovery?
Tephra (ash) hazards
Partners
Volcano H s Program Site
Tranporaion | Wate Sune | eter | Aslons | Cleans
What is Volcanic Ash? Volcanic ash brochures
Volcanic ash consists of tiny jagged pieces of | Two ash fall hazards pamplets published by the International Volcanic rock and glass. Ash is hard, abrasive, mildly Health Hazard Network (IVHHN) are available on the IVHHN corrosive, conducts electricity when wet,and Pamphlets webpage. does not dissolve in water. Ash is spread over broad areas by wind. | Ash properties & ash distribution | GUIDELINES ON THE HEALTH HAZARDS PREPAREDNESS What Is it like during an ash fall? OF VOLCANIC ASH BEFORE, DURING AND Falling ash can turn daylight into complete A guide for the public AFTER AN ASHFALL darkness. Accompanied by rain and lightning, a [Ss | the gritty ash can lead to power outages, wy prevent communications, and disorient people. Image as of 2 ]
bean for homes, businesses, & communities Taking action before, during, and after an ash fall can prevent or reduce many of the damaging effects of ash. Removing ash requires disposal sites and coordination among individuals and households, community organizations, and businesses. | Actions to take | Ash clean-up | Volomnia ail i. Managing ash fall in Yakima, Washington, from the 1980 eruption of Information relating ote — hazards of Mount St. Helens: Overview by Dick Zais, City Manager gases and aerosols typically emitted during volcanic activity are also available from the International Volcanic Health Hazard Network References and Web Links é : : ; < Raleeesianl be Sas wide = wa (IVHHN).See introduction to volcanic gases
° International Volcanic Health Hazard Netw ork poker sedcettial pollation rr guidelines based on international urban and
http: rroleanece! usgs.gov/ash/
A distal volcano may affect you the most
Tephra (ash) can affect communities far from source
124°W
400 MILES )
400 KILOMETERS & Mount Seager Annual
{inset map of Novarupta ash fall is at same scale,) ; a Mourt Cayley Probability | & Mount Garibaldi > 10cm
Arey howl 2h-cantury erupt ash fall thicker than about 0.2
Glacier Peak 4 ~ “4 ,
feast ciel eriphornes ¢ } y a Hereer. et) Gepomity, mist Pecks é hh , A Nout Baker
s Glacier Peak A Mt St Helens
YELLOWSTONE ASH Crater Lake erupted 666,000 years agc Mt Mazama)
MAZAMA ASH ee vellowstone erupted 7,600 yearn, ayo Caldera Complex
~ a 4 Wocunt Jetierson & Three Sisters ray Long Valley
Caldera ; & Crater Lake Anchorage e
Area al mag Mt Spurr,
A Newberry Volcano
ALASKA
BISHOP ASH erupted 760,000 years ago
from Long Valley "ACTE Novarupta """ A Medicine Lake Volcano cs A ce 4 Woont Shasta
OCEAN .SH 191 ; Lassen Volcanic Carter
Economic Impacts can last for decades Resuspension of volcanic ash, dredging sediment from lahars
ee ath 5% Me - ae <A ~s sl Oe e «s Uo wanes GALL os
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Eruption duration
Your volcano may be above or below average
Mount St. Helens, WA: 1980-86 Mount St. Helens: 2004-08
Eruption Duration n=39%4
Kasatochi, AK 2008: 20 hours Okmok, AK 2008: 3 weeks Redoubt, AK: 1989-1990; 5 months Crater Peak, AK: 1992, 3.5 months
<1 1-7 631 16 612 12 2-5 610 10:20 20
<—— ap ——> ¢- mows» <r ——_—_> Unzen Volcano, Japan: 1991-1994 Sourftriere Hills, Volcano, Montserrat: 1995 - present Santa Maria Voclano, Guatemala: 1923 - present
Small eruptions can be disruptive
Even small explosive eruptions have had world-wide affects
E-15 eruption was small, but affected 4 millions in Europe
Lightning often
occurs during ash e
eruptions; canaffect = = = s— CS A gee
nearby power and ” aE
communications x ——
Naa
Re-suspension of ash affected Icelandic communities for months afterwards
Small eruptions can be destructive
Hot rocks interacting with snow and ice can generate large lahars
23,000 people lost their lives hours after a small eruption at Nevado del Ruiz, Colombia in 1985
ere
Above: Nevado del Ruiz Right: The town of Amero after the about 1 month after the catastropic eruption on 13 November 1985
Prepare now! Educate your community.
¢ Get to know the hazards in your community
¢ Know the interagency response plan for your community
¢ Know what materials are available for training your CERT team
¢ Include volcanoes in your multi- hazard training
¢ Know how to inform your community (learn, inquire, plan)
Bringing it home to your community
Are you affected by lahars? [Explanation | Volcano Hazard Zones ¢ Do you have a regional lava flow Mi Proximal hazard | for Western Washington hazard? wi pane |_ and Northern Oregon ¢ Are you directly or indirectly affected [Dhtavastow nazar | eC Mount Baker by volcanic events? recningeon tnd’ ee >
Northern Oregon
¢ How could ash affect your recovery plans/ability to help a neighboring jurisdiction?
ae - - Glacier Peak py Seattle
HESS Ay Ss
i> Olympia ra Mount : > Rainier
Mount St. Helens r Mount 7 = cr Adams
oe
Mount Hood
Prepare!
yth Fo Birch roe a > “& Nooksack River “ . e Bay Ny Glacier
Ferndale Ke : PX . ‘ Be | ‘, =
Bellingham ®
Zz - Samish’ oks ‘
Bay < Lake f J Shannon
Concrete
Whatcom
Baker Lake
Skagit River ae elAnacortes S Ss 3 Hamilton Burling
\ ‘ <=: | aa a 20 % Glacier “Swinomi ot Peak
Indian@ Mount Hazard Res. ¢ -l\ r; 3) Vernon
Skagit . . . . Oak : ork Stillazuamish Rive ja Bay / Nn. For
http://volcanoes.usgs.gov/ publications/assessments.php
> COMBINE DEMOLITION! y | EMOLI vi 13
DEPRV & RAMEM LUNE
Know your role in an eruption response.
At the JIC - MSH crisis October 2004
Participate in classes, drills. Celebrate the volcano in your backyard!
Add volcano preparations to your CERT multi-hazard training materials
Lahar Warning Test
10 am, October 28", 2002
What:
* Test of the lahar warning procedures for the Puyallup and Carbon River Valleys.
* Outdoor warning sirens will be activated and will run three to five minutes.
* Local television and radio news stations may run the Emergency Alert Signal (EAS) test.
* NOAA weather radios will be activated during this test.
When: 10 a.m., Monday, October 28%, 2002.
Where: Orting, Sumner, Puyallup, and Fife
Why:
* Test the alert call-down process.
* Check the sound coverage throughout the valley. * Check the different alerting mechanisms.
* Remind valley residents of the need for sirens.
Questions? Please contact Pierce County Emergency Management, 253-798-7470.
Bringing it home to your community Messages USGS gives to the public
e Learn—Become knowledgeable about volcano issues. Learn whether you live, work or go to school in a volcano hazard zone.
e Inquire---Ask public officials how they advise you to respond.
e Plan---For how you and your family will respond in the event of any natural disaster.
Get to know the hazards in your community
Mount Baker
Birch
Lake Whatcom
§ Lake Shannon
10 Miles Skagit r
Bay 20 Kilometers
Oak Harbor
Simplified from Gardner and others, 1995, Potential Volcanic Hazards form Future Activity at Mount Baker, Washington, USGS Open-File Report 95-498
Get to know the hazards in your community
Glacier Peak
if y Lake Shannon
Skagit River _3 Concrete A
Hamilton > eed
ie Granite Fels Gt C2 92 ‘\
Lake | Stevens
Spada Lake
Get to know the hazards in your community
Mount Rainier
Federal Wayf —_/ SEE MAP ON PAGE XXX FOR HAZARD ZONES TO THE NORTH AND THE WEST a ee “a —~S
Auckleshoot Indian Res! ~* Enumclaw SS r \ ro Whiz. Greenwater h o N ; | 4 1 * NM A} . A & Wilkeson vd oa 7 {| 2" %, Rive National \P
Randle Cowl &
- Eo
Riffe Lake
Simplified from Hoblitt and others, 1998, Volcano Hazards from Mount Rainier, Washington, USGS Open-File Report 98-428
Get to know the hazards in your community
Mount Adams
a cf r ) i 2
‘ Yakima Indian
Regional Lava Flow
Mount
St. Helens Hazard Zone
Swift * \ “Trout Glenwood” Reservoir ~ Lake 7
ott and others, 1995, Volcano Hazards in the Mount Adams Region, Washington, USGS Open-File Report 95-492
Get to know the hazards in your community
Mount St. Helens
Toutleg?%
2 > \
f Silver Lake t
oi § anasas 152? 3
te SS ee OP ea py
“Johnston Ridge River
River 4 Af Cougar Rive,
: Reservoir Yale Lake
10 Mies
20 Kilometers
Get to know the hazards in your community
Mount Hood
Regional > )) Mount Adams Lava Flow Hazard Zone Carson
Cc Washouga Ca /
219
Sh Mount | Mount Hood 7 Hood ~
Village ee oS i C Rhododendron imperline ' Oe * 135)
Government
White RW" Timothy ee Lake
regon, USGS Ope n
Information transfer before and during crisis
‘Tareday, D
MOUNT ST. HELENS UPDATE
Curveas stamns is Vebcue Advisory (Alert Level 2); aviation calor code ORANGE. Ge w tates of senarcesty, low ene. mem anid volearac gases, and
erupbon, cheer ve Wot cause terarcoue comditres sales of the 4 descend i teraction of het rock: now andice. Thess hitees
crater ame frethe pose a neghaybie bi below the Sediment Retention Structure ( hen teodels, show that any ash Couds that
Potential ash hazards: Wind tivesaity tiem the Nat twaed recta
Potential ash hazards to aviation: Under cv y rats Cas travel 100 Hypothetical eruption of Mount St. Helens Volume = 10 million cubic meters, Column height = 12 km MMS (15km) forecast winds 00 hrs UTC 07 DEC 05 (16 hrs PST 06 DEC 05)
Recowt wbeswrvations; Clear ooricbhe science for a changing workd
ontinase at a rate of one aw
Mourn St. Holorrs Legend T Apo A Mowt St. Helens
Modeled Tephra Thickn
Ashfall modelling program by A.W. Hurst, NZ-IGNS Wind de OMA ARL
1) 2) 3) 4)
me 5)
Five lessons to apply:
V Cascade volcanoes are ‘active’ and functioning volcanoes doing what volcanoes normally do. Your volcano will erupt again. There will be a short period or warning. Multiple hazards and long-term uncertainties.
Economic impacts can last for decades.
There is demonstrated value in inter-agency preparation— anticipating needs, developing and practicing response plans, volcano monitoring, education.
The goal of planning ts to prevent nature processes from becoming human disaste
rs . . ‘ "
4
a Ey | Cascades Volcano Observatory 360-993-8973 www.vulcan.usgs.g
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