September Evening Public Lecture — Remembering Mount Pinatubo 25 Years
Remembering Mount Pinatubo 25 Years Ago: A look back at one of the largest volcanic eruptions of the 20th century. There was a special showing of the NOVA film "In the Path of a Killer Volcano" at this event which is not present in this video due to copyright issues. Following the viewing, however, USGS Geologist John Ewert (was who featured in the film) answered questions.
Location Taken: Meno Park, CA, US
00:00:02.380 --> 00:00:24.240
[ Silence ]
[inaudible background conversations]
Good evening, folks.
It’s very nice
to see you again.
You might remember my face
from two months ago.
I am Maggie Mangan, the scientist
in charge of the USGS California
Volcano Observatory, which is
stationed right here in Menlo Park.
You’re going to hear some more
about volcanoes today,
but this time from one of my
most hero colleagues, John Ewert,
who comes to us from the
Cascade Volcano Observatory.
Before I introduce him, though, I have
to do Leslie Gordon’s command.
And that is to tell you the title
of next month’s public lecture,
and it is Rockfalls in California’s
Sierra Nevada - Pursuing Explanations
for Exfoliation and Seemingly
Spontaneous Fracture of Rock.
Another exciting lecture, and this
one will be by Brian Collins.
He’s a USGS research civil engineer
in our landslide programs.
But tonight we’re
all about volcanoes again.
And as advertised, we actually have one
of the geologists – volcanologists that’s
featured in the film that you’ll see
tonight – In a Path of a Killer Volcano.
As I said, John Ewert comes to us from
the Cascade Volcano Observatory.
He’s actually been with the U.S.
Geological Survey for 35 years, I’m told.
Way before I was born.
I love this group.
But he’s been specializing
in volcano hazard mitigation
around the globe
for those 35 years.
He came right out of college in
May of 1980 when Mount St. Helens
was blowing up, and a few months later,
he had a job at the USGS
in the precursor to the
Cascade Volcano Observatory.
He worked there
for many years.
In 1986, he joined and helped found
the USGS/USAID Volcano Disaster
Assistance Program, which provides
assistance during volcanic unrest and
disaster around the globe, and
particularly in developing nations.
He worked for VDAP
from 1986 to 2010,
and he, as I said,
has worked all over the globe.
In 2005, he started to put on a
manager’s hat and worked on
some of our programmatic imperatives,
and that is the development of the
National Volcano Early
Warning System for the nation.
And maybe he’ll tell you
a little bit about that.
From 2010 to 2015,
John was the scientist in charge
of the Cascade
And after five years of management
and many years of programmatic duty,
he went back to what he loves most,
and that is working on volcano unrest
and partnering with the Volcano
Disaster Assistance Program.
But then, there was a stint in 1991,
on the island of Luzon in the Philippines,
that Mount Pinatubo
started to act up.
And John was there in the beginning
through the successful prediction
of the eruption and watching over
the volcano and the community
in the aftermath
of the eruption.
So John will be here to introduce
the film. Then we’ll watch the film.
I actually brought popcorn
to the 12:00. [laughter]
But that’s the one where all the
staff comes, and they ate it all.
So I’m sorry.
But we’ll watch the film, and then
we’d love to hear your questions
and thoughts about the film
and the work that we do here
at the USGS in volcano
[ Applause ]
- Thanks, Maggie.
Is this on? [loud noise]
Oh, yes, good. [laughter]
Okay. I just want to set
this up a little bit.
This is a long time ago
we’re talking about – 25 years.
And it’s a little bit difficult
for me to watch myself
from 25 years ago, so just
bear that in mind. [laughter]
So 1991 is five years after we
established the Volcano Disaster
Assistance Program in a
joint project with our
U.S. Agency for
And that program was started in 1986,
several months after the
Nevado Del Ruiz Colombia
catastrophe November 13th, 1985,
when Nevado Del Ruiz erupted and
sent volcanic debris flows, or lahars,
streaming off the volcano and
into heavily populated areas.
And over 23,000 people
lost their lives.
And the USGS made a
proposal to the international –
our Agency for International
Development, their Office of
Foreign Disaster Assistance, to stand up
a program of volcanologists who could
respond to developing crises
around the world, analyze the hazards,
get some data from the volcano,
and hopefully make forecasts
adequate to get people
out of harm’s way.
And so in 1991, we’re still
a very small group.
We were, I think, all of five people
at the time, plus members of our –
of the USGS from other
And this was really the first –
the first big test of the –
of the program, whether or not
it was going to go forward.
And actually, this year is
the 30th anniversary of VDAP,
so a little bit of
a spoiler alert.
And that’s a little bit remarkable to
have an inter-agency federal program
go for 30 years, so we have been
quite successful over that time.
Now, we work by invitation only.
Okay, we don’t hear about a volcano
waking up somewhere and go in
and say, hi, we’re here to help.
We need to have an
invitation from our hosts.
We’re guests in
And so, as a result, you know,
we never have a camera crew with us.
It’s just a bunch of scientists.
And not terribly artistic ones at that.
And so this movie is a little bit odd
in that there’s a lot of footage
that’s done in real time.
It was filmed as it was occurring.
The reason is, is because,
when we went to the Philippines,
we ended up being hosted on
Clark Air Base, which, at the time,
was the largest U.S. military
installation outside of the U.S. –
largest foreign base.
And not long after we got there,
the command at Clark Air Base
assigned a combat camera crew to us.
And their job was just to follow us
around with the cameras
and get on the helicopter with us
and go wherever we were going
and film what
we were doing.
And after the event occurred,
and Nova was very quick to realize
that there was a neat story here, the
producers were able to get a hold of the
combat camera footage, and they were
able to cut that in with the interviews.
And so what we have is a –
is a fairly remarkable documentary
as they unfold.
And the reason this film is still used
in universities and high schools,
and even middle schools, around the
world as a teaching tool is that it does
capture the uncertainty and the stress and
the buildup to a large volcanic eruption.
And in that regard,
it’s fairly unique.
Most of the – well, all of the other
documentaries that you’ll see
about volcanic activity certainly
are all done after the fact.
And this one has lots of footage
from the – from the event itself.
So with that, I think
we’ll start the movie.
There will be plenty of time
for questions afterwards,
and I don’t want to bore you.
Let the movie speak for itself.
[music from video]
So see you in an hour.
[ Music ]
[ Silence ]
- You look just the same.
- Thank you.
- Better glasses now.
- Yeah. They’re coming back.
So that was what we call a rich
life experience. [laughter]
It was a complicated event,
and, you know, the movie
can only capture so much.
There’s more to –
more to say, obviously.
I’m happy to take questions
about the event.
The microphones are
set up there in the middle.
I don’t know.
That’s the second time I’ve seen this
movie today, and it’s – it takes me back.
- Well, there’s, of course, been other
volcanic events, though, since that time.
And I don’t know if you’ve – the
application of your methods from
Pinatubo – what your success rate
has been statistically over time.
- Well, statistics of small numbers
are always a little bit odd.
We have had some very good successes,
both directly attributed to VDAP,
but also in the international
A few years later, in 1994,
there was an eruption at Rabaul,
a caldera in Papua New Guinea.
And this followed 11 years of unrest.
We refer to it as the eruption that
had 11 years and 28 hours of warning.
Because, after 11 years of dramatic
seismicity and uplift of the
caldera center, earthquakes started,
were quite strong.
And 28 hours later,
two volcanoes on either side
of the caldera
And yet, the town of Rabaul,
which had a population of
about 50,000 – because they had gotten
information from the volcanologists
about what to expect and what to do,
50,000 people auto-evacuated.
And there was
And that town was buried
under a meter of volcanic ash.
Other events that have occurred –
Montserrat in the British West Indies
In ’95 through – intermittently,
almost, to now.
That was a fairly
Merapi Volcano in Java
in Indonesia erupted 2010.
VDAP was involved
with that eruption.
There were a couple – 20,000 people
were evacuated out of areas that were
overrun by pyroclastic flows based on
the work that we were able to do
with our counterparts –
the Center for Volcanology
and Geohazards Mitigation
So there are examples.
We haven’t had an event of this
magnitude, obviously, since then.
There have been many
other smaller eruptions.
And the success rate is actually
getting quite a bit better.
One of the reasons this was
a successful response was that
we learned some
lessons from Ruiz.
And we took the matter of
communications with public authorities
and with the public
And after Ruiz, the International
Association of Volcanology
decided that we needed
some training aids.
And so we had Maurice and
Katia Krafft, a French couple –
volcanologists and videographers –
put together a movie.
USGS worked with them
on the – on the script.
It was called Understanding
And we had a rough cut of that in 1991,
and we were able to show it to the
base command and to
the local Filipino community.
And in there, you could see video of
pyroclastic flows and lahars and ashfall.,
and some fairly gruesome,
And that turned out to be
very effective at communicating.
Pinatubo had not erupted in 600 years.
There was no cultural memory of this.
And it wasn’t – it wasn’t a nice,
conical volcano on the – on the horizon.
People didn’t know
it was a volcano.
They thought we were crazy telling them
this was going to be a volcanic eruption.
But that video was reproduced and
reproduced and shown and shown
and explained many times in the
weeks beforehand – and in fact,
on June 3rd of that year, the event
that’s described in the movie
is where the Kraffts lost their lives
in the pyroclastic flow at Unzen.
And that, in itself, became
quite a powerful teaching –
teachable moment to say to people,
look, the couple that made this video
just lost their lives
in an eruption last week.
So we were fortunate to have it.
And I think, for the Kraffts, it’s a –
it’s really a nice tribute
to their – to their work.
And it’s been used since then
quite frequently around the world.
So been some – been some
successes – some notable ones.
Obviously nothing this big.
- So would those four cinder block
walls have protected you?
- That was my sweet hope.
- Did you go back?
We were back the next day.
And, yeah, I wouldn’t have wanted
to stay overnight there on the base.
A number of people did.
A number of Air Force security
stayed on the base and rode it out.
- So they survived, but they
probably weren’t too happy about it.
- Yeah. Well, the pyroclastic flows
came within 200 meters
of the upper part
of the base.
So we were actually lucky
that the eruption in ’91 was
a bit smaller than some of
the previous eruptions
that had occurred in the
past several thousand years.
If it had been a little bit bigger, they
would have easily come on to the base.
As it was, 14-1/2 thousand servicemen
and dependents were evacuated.
And had they been on the base, the
collection points that they designated,
which were in gymnasiums and
warehouses and buildings with
large roofs that could house people,
most of those collapsed.
And in fact, most of the fatalities –
the direct fatalities from the eruption
were from people being in buildings
that collapsed because of the weight
of the ash and the shaking
from the seismicity as the –
as the hole in the ground,
the caldera, formed.
- Okay. Thank you very much.
And by the way, if someone
had told me in 1991 in May,
you’re going to go to the Philippines,
and you’re going to be at
the second-largest eruption of the
20th century on the same day
that a typhoon comes to shore
and tracks over the top of the volcano,
I would have said no.
That’s not a real scenario.
Because stuff like that doesn’t happen.
But there you –
but there you have it.
And that’s actually an important
lesson that I – that I teach to
emergency managers when I –
when I speak to them.
When we’re – when we’re talking
about their volcano, wherever it is,
I say, look, there’s – it’s worth
planning for the worst case.
the worst case happens.
And that’s a – that’s a message certainly
that I’ve internalized in the last 25 years,
that, you know, Hollywood can’t
write this stuff. [laughter]
Nature is quite amazing.
- I have two questions for you.
The first one is a light one.
At 33, you said,
where do you go from here?
And I was wondering
where that was.
- My mother-in-law is reported
to have said, have babies!
My oldest son in 23.
My youngest son is 17.
And that was – is, in my opinion,
probably bigger. [laughter]
So that’s the – that’s the
answer to that one.
- So my next question is,
during the – during the film,
you’re in the helicopter,
and you can see the dome down there.
And it says in the film that it would be
nice to have some of the material
from the dome to –
I’m going to guess,
to make an analysis on the
gaseous content of the material.
And I was wondering
what that might be
and what you could tell by that sample if
you had been able to get that [inaudible].
- As it turns out, I think we’re
lucky that we didn’t get a sample.
Because it would have –
it would have thrown us off.
When we went back the next year
to look at the deposits –
after the erosion had
taken place, we had exposures.
We could look down into the –
in the riverbeds and see
from June 12th on.
And we found fragments
of the lava dome that were
in those early explosive events –
the vertically directed eruptions.
And they were of a
composition called andesite.
And all the other deposits that
we’d looked at were dacite,
which is a more
And if we had known it was andesite,
which tends to not be as explosive as
dacite – behaves a little bit differently,
we might have been thrown off.
As it turns out, that andesite was
created by an intrusion of
fairly primitive basalt from great depth
into the pre-existing sponge, or magma,
reservoir, which was dacite,
which was almost in a rigid state.
It was 60% crystalline.
That hot basalt, which was several
hundred degrees centigrade hotter,
had a lot of volatiles in it – rejuvenated
that system – mobilized it.
And the mixing of the compositions
is what produced that andesite,
which was the
first material out.
And we got some important insights,
actually, to what triggers these
big eruptions from learning about
the dome and analyzing the rock.
So it would have – it would have
been a little bit confusing for us
to actually have the sample – were we
able to get one, were we able to get an
analysis quickly enough, which probably
wouldn’t have happened – yeah.
Yes? In front.
The movie mentions a
drop of 1 degree for five years.
- That’s Fahrenheit.
Yeah. It’s a 1/2 a degree C
is what we had.
And a lot of good science
came out of tracking the impact
of that aerosol injection
of the stratosphere.
Learned a lot about circulation patterns,
about aerosols and their longevity
in the stratosphere, the reflectance
that occurs and the cooling of
the troposphere and the warming of the
stratosphere that actually went with that.
So we learned a lot
about climate change
and the impact that
volcanic activity can have.
- I was wondering if Mount Rainier
is posing a lot of risk.
- Yes, but differently.
Mount Rainier is a rather large
volcano in the state of Washington.
It’s covered with a cubic kilometer –
or actually a cubic mile –
4 cubic kilometers
of snow and ice.
A little bit less
The danger at Rainier is lahars –
volcanic debris flows.
The volcano sits 14,000 feet
above the Puget Sound lowland.
And in Holocene time – that is,
in the last 12,000 years,
it has generated 55 lahars,
which have come sweeping down
off that volcano and into what are
now heavily populated areas.
There are over 100,000 people
and probably $10 billion of
built environment that are
built on young debris flow,
or lahar deposits,
from Mount Rainier right now.
When that volcano does re-activate
and wake up, it’s going to be
a major problem, but not
because of its extreme explosivity,
but because of its potential to mobilize
all that frozen snow and ice up high.
- What’s the most likely eruption in the
United States in the next hundred years?
- [inaudible] prediction.
- So what’s the – what’s the most
likely next place for an eruption?
Statistically, right now, it’s
Kilauea because it’s been
erupting continuously since 1983.
And if we want to look at more statistics,
it would probably – and we were
concerned about an explosive volcano,
it would certainly be in Alaska.
But basically, any one of the
strata volcanoes in the Cascades,
from Lassen in northern California,
north to Baker in – almost at the
Canadian border in Washington
any one of those has had eruptions
in Holocene time,
in the past 12,000 years.
Any one of them could light up
tomorrow and wouldn’t surprise
any of the volcanologists
here in the U.S. or globally.
It’s just – it’s not something that
we can really foresee that far out.
We’ll do a lot better if we can
have monitoring instruments
in the ground close in on the
volcanoes and learn early on
when they’re just
starting to re-awaken.
We’re – we’ve come up quite short,
actually, in the extent to which
we are monitoring our potentially
active volcanoes in the U.S.
So interesting thing about the
Pinatubo eruption is that we talk –
there’s a lot of talk about
the earthquakes afterward.
These were magnitude 4-1/2
to 5.7 occurring several times an hour
for a day – a couple of days, and then
obviously less frequency with time.
Before – those were afterwards
as the crust is re-adjusting
to having all the material
taken out of it.
Beforehand, the biggest
earthquakes we had were, like,
magnitude 2-1/2 to 2.8, maybe.
They were sensible to some of
the local villagers who were
living on the northwest
side of the volcano.
You know, living in a quiet
setting, sitting on the ground.
But kind of remarkable when you
think the magnitude of the eruption
was preceded by just a lot of
really tiny, tiny earthquakes.
And that’s kind of the – that’s what
we’ve learned about volcanoes
in general is that you really have to be
looking closely at what they’re doing
to really get the longest warning
that they are re-activating.
So if we’re watching, if we’re paying
attention, if we have the means to watch,
we’ll probably catch early enough
the next re-awakening volcano,
but we’ve got to have the
instruments in the ground
and the people paying
attention to do the job well.
- Hi. So right in the beginning of the
talk, before the video, you stressed that
VDAP only goes in by invitation
with the local authorities.
So could you talk more
about the role of you folks?
Because the video
doesn’t really show that.
And as well as, in the situations that
follow, how VDAP works with local
authorities in other situations.
The Philippine Institute of
Volcanology and Seismology,
PHIVOLCS, is the USGS
counterpart agency in the Philippines.
And at the time in 1991, they had
a lot of their younger staff out of the
country in Japan, New Zealand,
other places, getting advanced degrees.
They were short-staffed.
There was also some unrest
being recorded at Taal Volcano,
which is south of Manila –
also a large caldera.
And they were needing to
pay attention to that.
This is a volcano
that’s erupted frequently,
and quite large magnitude,
over the years.
And they had –their
at the time was
there as well.
So Chris Newhall, who had worked in
the Philippines – he’d been a Peace
Corps volunteer there for two tours –
knew Ray and – collegial relationship.
Ray was, like, okay,
I’m kind of overwhelmed here.
I’ve got – I’ve got two things
going on. I could use some help.
And so he asked
for us to come over.
And the request went through
the U.S. Embassy, through the
U.S. Agency for International
Development at the embassy.
And they thought it was not worthy
of asking the USGS to come.
The command at Clark Air Base,
who was within 20 kilometers
of the summit of the volcano,
and they were smelling the sulfur,
they were getting
It was they who tipped the balance
and leaned on USAID and said, look,
PHIVOLCS is requesting it.
We’re requesting it.
Get USGS over here.
So after the eruption, you know,
PHIVOLCS did a very good job with us.
VDAP did a good job.
For some reason, their funding
went up quite a bit. [laughter]
And they now have a very nice national
seismic network, and they have
volcano observatories on most of
their potentially active volcanoes.
For VDAP, this was
the validating event.
I said at the start, you know,
we were just five years into
growing this program.
And we – you know, we demonstrated
that, look, with a team, with equipment,
with expertise, that we could go in and
get people out of the way ahead of time.
And the cost-benefit of it
was really kind of amazing.
So other places around the – around the
Pacific Rim where VDAP has worked,
it’s just about everywhere that has
active volcanism that is
not New Zealand and is not Japan
and is not Russia, at this point.
So basically, from – in Latin America,
from Mexico, south through Chile,
we have a large program going
right now with Indonesia.
Also in Papua New Guinea and
a couple of countries in Africa.
So we manage to keep busy.
I don’t know if that – if that
addresses your question. Okay.
- Thank you, John.
Very impressive and very dramatic.
And certainly very encouraging for
young volcanologists like us too.
And in the film, I’ve noticed
that it seems that you have been –
you were using roughly the same
methods and technology that –
to evaluate the explosivity of the volcano
as a lot of people are still doing now.
So my question is, like, during this
25 years, what do you think
is the greatest breakthrough
in science and technology
in predicting the volcano
- Great question.
Well, we still look
at fundamental things.
We look at the seismicity.
We look at deformation – how the –
how the crust responds to material
being added beneath the volcano.
And we look
at gas emission.
In 1991, there were
very, very few civilian satellites
that produced data that were
useful for volcano monitoring.
Now we have systems on orbit that
allow us to track passive emission
of sulfur dioxide – the OMI mission,
AIRS, some of the other infrared
and UV satellites allow us to actually
make measurements from space,
if it’s not too cloudy, of gas
coming out of volcanoes.
very useful to us.
Instances in South America and –
well, really around the world –
allowing us to track gas output beforehand.
That’s a great new thing.
InSAR – interferometric
synthetic aperture radar –
wasn’t on anyone’s radar
at the time. [laughter]
Hadn’t really been invented until –
I think the first paper was
after the Hector Mine earthquake
when we saw that there was
accompanied that in 1993.
Now we have a number of satellite
systems on orbit that allow us to
track deformation anywhere from
week to week to month to month.
You know, we’re not able to do it on
a day-to-day basis, but getting better.
We’re learning a lot about systems that
are seismically quiet but are deforming.
That are – that are showing us that
there’s intrusive activity taking place.
In 1991, digital seismometers
were still very new.
24-bit systems were, you know,
research things that a couple people had.
digital and 24-bit.
We were using analog seismometers –
Gosh, what else?
There’s been so many developments
in remote sensing, in our ability
to track carbon dioxide.
Carbon dioxide is a – is kind of the
frontier, in my opinion, on gas research.
It’s tricky, though.
I mean, we’ve got – well, this year,
we’ve got 400 parts per million carbon
dioxide in the atmosphere, and it’s
a colorless, odorless gas, unlike sulfur
dioxide or hydrogen sulfide.
So it’s a little bit more
difficult to tease that signal out of –
out of the
But carbon dioxide
comes out of magma
at a deeper depth and
earlier than the sulfur gases.
And if we would be able to track
carbon dioxide emissions at
non-erupting volcanoes at
this point, I think we’d learn a lot.
So a lot of new
things have come online.
A lot of countries now
have national seismic networks.
They have infrastructure
that allows us to kind of
see what the background
activity is at young volcanoes.
And what we’re learning is that the
volcanoes that are sitting there,
apparently passively, not doing anything,
not even producing visible steam
plumes, a lot of these are having
repeated seismic swarms –
earthquake swarms, telling us
that they’re getting fed from below.
They’re getting intrusions of magma,
but they’re not resulting in eruptions.
And this is a – this is kind of a neat
revelation for us, I think, to understand
that volcanoes can actually be quite
active and yet be not visibly so.
Okay, so they’re functioning –
they’re functioning systems.
They just happened
to be in a dormant state.
So lots of stuff like that is –
has happened in the last 25 years.
So too much to
cover right now, I think.
At the microphone first, please.
- Are you doing any monitoring of the
hot spot under Yellowstone Park?
- Personally …
Well, we have a – we have a
Yellowstone Volcano Observatory.
And Jake Lowenstern here in Menlo
Park is the scientist in charge of that.
And that monitoring is conducted
in cooperation with the
University of Utah Seismographic
Stations – the UUSS, so – as well
with the Plate Boundary
Observatory through UNAVCO.
So there is – there is a pretty
good monitoring network in –
at Yellowstone now.
It’s tracked pretty closely.
- Would you describe how big
Yellowstone is in comparison
to Pinatubo, and what might
- Yeah, so Pinatubo,
we brought probably
6 or 8 cubic kilometers
of material out of the ground.
Eruptions at Yellowstone
bring 1,000 or more.
So they’re different.
And this is about the right distance to
observe a Yellowstone eruption from.
I mean, yeah, Yellowstone is a –
you know, it’s a – it’s a super –
That is a term of art that’s
used for volcanoes that have
had eruptions of 1,000 cubic
kilometers or more in their past.
And those are – those are
game-changers for the planet.
Okay, those are – those are events
where species come and go.
So, you know, it’s really highly unlikely
that anybody in this room is going to –
going to see an eruption of that
magnitude at Yellowstone.
And in fact, most of the eruptions
that Yellowstone produces
are fairly small and
confined to the park.
You know, there’s a lot of eruptions
there that are non-explosive that
bring rhyolite composition magma to the
surface, and they make these domes
and flows at the surface, and they’re
not big, scary planet-changing events.
But by far, you know, by number,
that’s the – that’s the most likely
thing to occur at Yellowstone is
actually a fairly small eruption.
When we see a number of those
eruptions coming in a fairly short
geologic span of time – a few thousand
years, we might begin to think that
the system is preparing
for another big eruption.
- Maybe we better let you go?
He hasn’t had his dinner yet.
- Okay. Thank you.
[ Applause ]
[inaudible background conversations]