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2011 Partners in Preparedness Conference2011 Partners in Preparedness Conference
10 things you need to know about the 10 things you need to know about the l i b k dl i b k dvolcano in your backyardvolcano in your backyard
Cynthia Gardner and Carolyn DriedgerU.S. Geological Survey, Cascades Volcano Observatory26 April 2011
Course Outline
1 Your volcano will erupt again1. Your volcano will erupt again2. You will get warning (monitoring, messages)3. The warnings will not be black and white, i.e, there is a
l t f t i t i d li ith l i ti itlot of uncertainty in dealing with volcanic activity4. Emergency managers will need to make decisions and
take actions long before outcomes are known5. The types of hazards are known - IAVCEI video6. Near-source hazards can develop rapidly - evacuation
prior to an event will be necessary (issues about long-prior to an event will be necessary (issues about longterm evacuation; funding for closures, etc.)
Course outline (cont.)
7. Lahars (volcanic mudflows) follow river valleys that start on volcanoes - affects may last long after eruption is overvolcanoes affects may last long after eruption is over
8 Tephra (volcanic ash) moves in the direction and at the speed of the wind - it will take time to get downwind
9 Th l l t t t b th l th t9. The volcano closest to you may not be the one only one that affects you
10. Volcanic eruptions can last for days to years and do not have to be large to be disruptive
Bringing it home to your communityBringing it home to your communityScenario
Do you have questions that you want answered in this course?Do you have questions that you want answered in this course?
Your volcano will erupt againSubduction is the process behind many hazards in the PNW
1Subduction is the process behind many hazards in the PNW
• Subduction earthquakes >>> volcanic earthquakes• Volcanic eruptions are rarely triggered by a subduction eqs
Your volcano will erupt againC d l h l lif d t hi t iCascade volcanoes have long life spans and recent histories
Your volcano will erupt againp gNot all volcanic eruptions occur at the big volcanoes
By Jason Brewer, 1977
You will be warned2
Volcanoes often give days to months of warning
As magma moves to the surface:As magma moves to the surface: Surface deformation
•• It breaks a pathwayIt breaks a pathway•• It releases gasesIt releases gases•• The chamber or conduit mayThe chamber or conduit mayThe chamber or conduit may The chamber or conduit may increase or decrease in volumeincrease or decrease in volume
These processes result in effects These processes result in effects that we can measure: that we can measure:
•• EarthquakesEarthquakes•• Emission of magmatic gasesEmission of magmatic gasesEmission of magmatic gases, Emission of magmatic gases, principally COprincipally CO22 and S gasesand S gases•• Ground deformationGround deformation
Input ofmagmaInput ofmagma
You will be warnedM it i i ti l t l d t ti f t tiMonitoring is essential to early detection of unrest, eruption
and hazardous events
USGS mandate is to provide warningp gUSGS alertUSGS alert--level system focuses on the state of the volcano with an level system focuses on the state of the volcano with an
emphasis on ash for the aviation communityemphasis on ash for the aviation community
TERM COLOR DESCRIPTIONDESCRIPTIONAlert level Aviation Color Code
Volcano is in normal non-eruptive state
Volcano is exhibiting signs of elevated unrest
GREEN
YELLOWElevated unrest above known
NORMAL
ADVISORY
Typical background, non-eruptive state
Volcano is exhibiting signs of elevated unrest above known background levels
Volcano is exhibiting heightened/escalating unrest with increased potential of eruption
OR ti d ith
YELLOW
ORANGE
Elevated unrest above known background activity
Heightened/escalating unrest with increasedpotential for eruptive activity. timeframe variable OR minor eruption underway
ADVISORY
WATCHOR, eruption underway with no or
minor ash emissions
Eruption is forecasted to be imminent with significant emission of ash into the
atmosphere likely OR, RED
variable, OR, minor eruption underway that poses limited hazards
Highly hazardous eruption underway or imminentWARNING p y
Eruption is underway with significant ash into the atmosphere
or imminent
You will be warnedKnow your communication links
C ll DCall Downsex. Mount St. Helens
C ll d d hCall downs are used when changing alert-levels, to update officials about a
significant change insignificant change in activity, or when eruptive
activity ceases
How do you fit into this call down?
You will be warnedKnow all of your sources of information and how youKnow all of your sources of information and how you
will be informed
Scientific information:Scientific information:• USGS and PNSN for volcanic activity•USGS for warning - Alert•USGS for warning - Alert Level System• USGS and NWS for ash fall and lahar warningsand lahar warnings
Response Information• NIMS/ Unified Command
Websites: http://volcanoes.usgs.gov
S/ U ed Co a d• Interagency response plans
Public information• Media• Social media
Alert Level Change - Normal to AdvisoryProbably most difficult step for scientists
Diffic lt to pinpoint hen something is o t of the ordinar• Difficult to pinpoint when something is out of the ordinary• Likely to bring intense media scrutiny• Joint Information Center likely needed• Responders should start reviewing plans• Conference calls• No promise of that an eruption will occurNo promise of that an eruption will occur
Warnings will not be B&W3
Scientists cannot directly measure the magma system
Like weather systems uncertaintySurface
deformation Like weather systems, uncertainty about outcome (size, style, timing, eruption/no eruption, vent area) is high
deformation
high
Unlike weather systems, we don’t yet have physics-based models to
Everything we want to know is
forecast outcome
beneath ground and we don’t yet have instruments to directly measure what it is that we
o ld like to knoInput ofmagma would like to knowmagma
Warnings will not be B&WWarnings will not be B&WAll Cascade volcanoes show a range in eruptive size and style
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.
Warnings will not be B&WWarnings will not be B&WVent location determines what areas will be affected
Warnings will not be B&WV l i t ll l t l th th t lV l i t ll l t l th th t lVolcanic unrest generally lasts longer than other natural Volcanic unrest generally lasts longer than other natural
hazardshazards
Event DurationWarningHazardous Event Weeks to
monthsDays Days Weeks to
monthsMonths to years
Flood
Hurricane
y
Earthquake/tsunami
Hurricane
Wildfire
Eruption
Wildfire
Hazardous events can occur during unrestHazardous events can occur during unrest
EMs will need to make decisions long EMs will need to make decisions long before outcomes are knownbefore outcomes are known
5
“Decision window”
before outcomes are knownbefore outcomes are known
for public officials
Shape, character, aram
eter
s
p , ,duration very irregular
Build-up suggests eruption is likelyni
torin
g pa
eruption is likely
Cannot guarantee that eruption will not occursi
ty o
f mon
e up o o occu
Inte
ns
Time
EMs will need to make decisions long before outcomes are known
Eruption1
before outcomes are knowns
Decision window for Eruption1 Eruption 3
aram
eter
s public officials
onito
ring
pans
ity o
f mo
Back tosleepBack to
sleep2 4
Inte
n
Time
Decision making across culturesScientists and public officials who understand eachScientists and public officials who understand each other’s culture beforehand, will likely work well together
Scientists
Public officials
We all want to succeed, we all need to succeed
Volcano hazardsN t thi ill ff t t
5
Not everything will affect you at once
•• Proximal areas ( ≤15 mi) subject Proximal areas ( ≤15 mi) subject t lti l l th l h dt lti l l th l h d i tto multiple lethal hazards: to multiple lethal hazards: minutes to tens of minutes
•• Intermediate areas (> 15 <100) Intermediate areas (> 15 <100) Lahars, tephra fall and floods affect Lahars, tephra fall and floods affect river valleys: river valleys: tens of minutes to hours
•• Distal hazards (>100 mi) Distal hazards (>100 mi) -- Tephra Tephra fall affects areas downwind: fall affects areas downwind: hour(s) to days( ) y
•• Excess sediment in watersheds Excess sediment in watersheds reduces flood capacity: reduces flood capacity: week(s) to decadesdecades
Volcano Hazards
IAVCEI videoIAVCEI videoInternational Association for
Volcanology and Chemistry of theVolcanology and Chemistry of the Earth’s Interior
Volcano hazardsN t thi ill ff t tNot everything will affect you at once
•• Proximal areas ( ≤15 mi) subject Proximal areas ( ≤15 mi) subject t lti l l th l h dt lti l l th l h d i tto multiple lethal hazards: to multiple lethal hazards: minutes to tens of minutes
•• Intermediate areas (> 15 <100) Intermediate areas (> 15 <100) Lahars, tephra fall and floods affect Lahars, tephra fall and floods affect river valleys: river valleys: tens of minutes to hours
•• Distal hazards (>100 mi) Distal hazards (>100 mi) -- Tephra Tephra fall affects areas downwind: fall affects areas downwind: hour(s) to days( ) y
•• Excess sediment in watersheds Excess sediment in watersheds reduces flood capacity: reduces flood capacity: week(s) to decadesdecades
Proximal hazards6
Near source hazards can develop rapidly
30 i t l i ti30 minutes or less warning time too short to detect the activity, give warning and take action
Officials have difficult decisions:• Limiting access• Road closures• Evacuations• Alternate escape routes• Warning system• Securing the closed area• Securing the closed area• Recovery issues
Big questions -- duration, g quest o s du at o ,resources and resiliency
Lahar hazardsL h i ll th t t t th l
7
Lahars occur in valleys that start on the volcano; generally not all valleys affected
Know which rivers start on your lvolcano
Ask scientists where the most likely vent area will be and what rivers it might affect
Have a plan to deal with reservoirs on potentially ff t d iaffected rivers
Lahar hazardsLahar hazardsHazards can persist long after an eruption is over
Lahar hazardsa a a a dsHazards can persist long after an eruption is over
Bridge crossing immediately affected by the eruption; months latermonths later
Some communities in the Philippines were not affected untilPhilippines were not affected until years to a decade after the eruption
Tephra (ash) hazards8
Tephra (ash) hazardsTephra moves in the direction(s) of and at the speed(s) of the wind
How far downwind are you? In what direction?
Tephra (ash) hazardsep a (as ) a a dsTephra affects aviation, which may impede recovery efforts
• ~2000 flights over the Cascades daily• Ash can reach cruise altitudes in a matter of minutes
How would reduced aviation affect your recovery?
Tephra (ash) hazardsM i 1980Many more resources since 1980
http://volcanoes.usgs.gov/ash/
A distal volcano may affect you the mostTephra (ash) can affect communities far from sourceTephra (ash) can affect communities far from sourceTephra (ash) can affect communities far from sourceTephra (ash) can affect communities far from source
9
Eruption duration10
Volcanic events can last for weeks, months, decadesVolcanic events can last for weeks, months, decades
Event DurationWarningHazardous Event Weeks to
monthsDays Days Weeks to
monthsMonths to years
Flood
Hurricane
y
Earthquake/tsunami
Hurricane
Wildfire
Eruption
Wildfire
Eruption durationEruption durationYour volcano may be above or below average
Mount St. Helens, WA: 1980-86Mount St. Helens: 2004-08
Kasatochi, AK 2008: 20 hoursOkmok, AK 2008: 3 weeksRedoubt, AK: 1989-1990; 5 monthsC t P k AK 1992 3 5 th
A d ti <6
Crater Peak, AK: 1992, 3.5 months
Unzen Volcano, Japan: 1991-1994Sourfriere Hills, Volcano, Montserrat: Average duration <6 mos , ,1995 - presentSanta Maria Voclano, Guatemala: 1923 - present
Small eruptions can be disruptiveEven small explosive eruptions have had world-wide affects
E-15 eruption was small, but affected millions in Europe
Lightning often occurs during ash eruptions; can affecteruptions; can affect nearby power and communications
Re-suspension of ash affected Icelandic communities for months afterwards
Small eruptions can be destructivepHot rocks interacting with snow and ice can generate large lahars
23 000 l l t th i li h23,000 people lost their lives hours after a small eruption at Nevado del Ruiz, Colombia in 1985
Above: Nevado del Ruiz Right: The town of Amero after the about 1 month after the catastropic er ption onthe catastropic eruption on 13 November 1985
Bringing it home to your community
• Get to know the hazards in your communityyour community• Know the interagency response plan for your community• Know what materials are available for training your g yCERT team• Include volcanoes in your multi hazard trainingmulti-hazard training• Know how to inform your community (learn, inquire, plan)
Bringing it home to your communityK h t h d ff tKnow what hazards affect your area
• Are you affected by lahars?• Do you have a regional lava flow hazard?• Are you directly or indirectly affected by volcanic events?
H ld h ff t• How could ash affect your recovery plans/ability to help a neighboring jurisdiction?
Bringing it home to your communityF ili i lf ith th h d d th thFamiliarize yourself with the hazards and the ways they
could affect your community
http://volcanoes.usgs.gov/publications/assessments.php
Bringing it home to your communityF ili i lf ith ’ l dFamiliarize yourself with your agency’s response plan, and
your role in unified command
At the JIC - MSH crisis October 2004
Bringing it home to your communityg g y yAdd volcano preparations to your CERT multi-hazard
training materialsg
Bringing it home to your communityBringing it home to your communityMessages USGS gives to the public
• Learn—Become knowledgeable about volcano issues. Learn whether you live, work or go to school in a volcano hazard zone.
• Inquire---Ask public officials how they advise you to respondto respond.
• Plan---For how you and your family will respond in the event of any natural disaster.in the event of any natural disaster.
The goal of planning is to prevent natural processes from becomingnatural processes from becoming
human disasters
Cascades Volcano Observatory Cascades Volcano Observatory y360-993-8973 www.vulcan.usgs.gov
y360-993-8973 www.vulcan.usgs.gov
Scenario - Mount HoodScenario Mount Hood
What’s at risk - Mount Hood• Community of Government Camp at base of volcano; other communities within 30 minutes of being affected by lahars
• Hwys 26 and 35. Hwy 26, major route to central Oregon with over 8200 vehicles passing by Government Camp daily.
•• Major air traffic route into Portland, flying at altitudes <25k; over 600Major air traffic route into Portland, flying at altitudes 25k; over 600 commercial flights/day = ~120,000 people/day; ~1700 tons/day air cargo; 30th largest airport in the U.S.
• Bull Run watershed major water supply to Portland; some pipes still• Bull Run watershed, major water supply to Portland; some pipes still exposed in lahar hazard zone
•• Four ski areas; summer training grounds for US Ski Team. Prime backcountry recreational area.
• Iconic Timberline Lodge on flank of volcano; major tourist destination
Potential to affect Col mbia Ri er ater a barging fish ater q alit• Potential to affect Columbia River waterway: barging, fish, water quality
Hazard zones - Mount HoodHazard zones Mount Hood
Mount Hood eruptive stylep y
•Few sustained explosive events (>1Few sustained explosive events ( 1 hour)
• Lava flow or lava dome growth and collapse collapses difficult tocollapse - collapses difficult to predict
•Dome collapse results in hot rock interacting with snow and ice to produce lahars
• Dome collapse results in ash pclouds lofting to altitudes of 15,000 to 30,000 feet and drifting downwind (normally eastward)
How are you being affected?How are you being affected?How are you getting information?y g g
What information do you want?
What actions are you taking? Unified Command/JIC?
?How are your resources holding up?
How are you getting information out?y g g
What questions are you getting from your community? From the media?From the media?
Notes or Action Items
Notes or Action Items
Mount Hood scenario: Days 1-14Mount Hood scenario: Days 1 14• Day 1: USGS detects eq swarm; nothing unusual mentions swarm in weekly update
• Day 3: Swarm continues; USGS releases Information Statement noting continued activity; picked up by some local media
• Day 6 (Saturday night): Three mid-M3 eqs and 5 high M2 eqs rock volcano; felt y ( y g ) q g qat TL and Govt. Camp; USGS changes Alert Level to Advisory early Sunday a.m.
• Day 7: Poor weather, can’t see volcano; media calls increase considerably: eqs continuing mostly M1s and 2s but at higher rateq g y g
• Day 9: Weather clears; detection of minor CO2 and H2S; no obvious changes at volcano, but eqs continue as do media inquiries
• Day 10: Several more M3 eqs; mid-day under clear skys, steam and ash emission; higher gas output; USGS raises alert level to Watch; USFS closes down mountain • Day 14: First steam and ash emission to 25 000 ft ; last 10 minutes and• Day 14: First steam and ash emission to 25,000 ft.; last 10 minutes and drifts eastwards; vents located north of Devil’s kitchen area
Mount Hood scenario: Days 14-28Mount Hood scenario: Days 14 28• Day 14: First steam and ash emission to 25,000 ft.; last 10 minutes and drifts eastwards; vents located north of Devil’s kitchen area;
• Day 15: Another steam and ash emission to 20,000 ft lasting 25 minutes, moving westward; instrument placed on Crater Rock to look at movement: gas output increases; media and tourists flocking to areap g
• Day 16-19: Poor weather and intense rain; instrument suggests movement of Crater Rock, but no confirmation due to weather; two more explosion signals; small lahar generated in White and ZigZag rivers
• Day 20: Good weather; Gas output increased 2 fold since last measurement, with notable SO2; USGS indicates unrest increasing, but does not change alert level; lahars appear related to rain, not volcanic activity• Days 21-28: Good weather continues; gas measurements up, but steam and ash explosions cease; eqs continuing at moderate levels; public interest high; minor movement of Crater Rock
How are you being affected?
No declaration - will you be able to maintain vigilance?
What information do you need to make decisions?
Are any areas closed?Are any areas closed?
What pressures may be pushing back at you?
Mount Hood scenario: Days 28-49• Days 21-28: Good weather continues; gas measurements up, but steam and ash explosions cease; eqs continuing at moderate levels; public interest high; minor movement of Crater Rockmovement of Crater Rock
• Day 32, July 4th weekend: New seismic signal appears, USGS believes eruption imminent, raises alert level to highest level (Warning)
• Day 35: No eruption has occurred, USGS decreases alert level back to intense unrest (Watch)
•Day 40, late evening: size of eqs decreasing, but rate increasing; glow seen in y g q g g gDevil’s Kitchen area; Alert level raised to Warning
• Day 41: Lava dome extrusion begins. Later in day, explosion destroys growing dome and sends ash to 35,000 feet drifting westward; small lahar generated do e a d se ds as to 35,000 eet d t g est a d; s a a a ge e ateddown White River
• Day 49: Lava dome growth continues, grows rapidly, major failure in mid-day sends lahar down White and Sandy River: on White reaches confluence withsends lahar down White and Sandy River: on White reaches confluence with Deschutes, on Sandy reaches town of Sandy, 20 feet thick in Welches…
Friday, 29 August (3 years later)
A small dome collapse yesterday was 200th collapse since the eruption began; ash cloud p p greached 25k feet, ash drifting westward; Portland received light dusting
Alert Level has been downgraded to Watch/Warning from Warning/Red as there is no longer any collapse activity
Gas, seismicity still well above background
In the past 3 years ago, > 90 ft of sediment has been deposited in former location of Timberline Lodge and in headwaters of Sandy River; river has aggraded over 45 ft in reach near Welches; air traffic has been disrupted for parts to all of 115 days out of past 1095 days since eruption beganparts to all of 115 days out of past 1095 days since eruption began
Notes or Action Items
Get to know the hazards in your community
Mo nt BakerMount Baker
Get to know the hazards in your community
Glacier PeakGlacier Peak
Get to know the hazards in your community
Mount RainierMount Rainier
Get to know the hazards in your community
Mount AdamsMount Adams
Get to know the hazards in your community
Mount St HelensMount St. Helens
Get to know the hazards in your community
Mount HoodMount Hood