Hi everyone I am so happy that Sarah has
invited me to talk to all of you today
and let me know if I have any classrooms
here say hi let me know we are from but
for now I will get on to the questions.
Oh I see I have some students from an
elementary in Orlando, Florida. Hi, you
guys don't have any volcanoes down there
but you never know you might travel to
them one day, so I'm going to get
straight on to some of the questions. I
have some questions from Emily — oh hi
classroom Medford, Oregon, happy to have
you here. So the first question I have
is why did I choose Volcanology. Well
this one's, I don't really feel like I
chose it, I feel like volcanology chose me,
so I don't remember when I started
getting interested in volcanoes but it
was when I was very very very very small
in fact I don't remember when I didn't
love volcanoes, but I didn't know it was a
real job, I didn't know any scientists,
I'm from a small town in New Zealand
called Te Awamutu, but I did grow up
surrounded by extinct volcanoes so
volcanoes that'll never erupt again, and
when I was 13 years old I was sitting in
my geography class and my teacher had
put volcanologist on the board and he
explained what that was and I sat back
and I thought, wow that's what I am. So
I'm a volcanologist, that means I study
volcanoes, and now I'm at Concord
University, and that's a university in West
Virginia in the United States. I did my
PhD at the University of Pittsburgh but
originally from New Zealand so I've been
moving around a little bit. What kind
of classes did I take in undergrad? Oh, hi,
hi Glenburn and Maine and Ohio and
also Kansas, wow you guys are from
everywhere thank you so much for joining.
So the classes that I've taken through
undergrad were really diverse, but they
were mostly all to do with studying the
earth, so whether that was specifically
volcanoes, or hazards and weather, and
climate, environmental science, classic
geology classes like sedimentology, so
how sediments form rocks, tectonics, how
tectonic plates move around, as well as a
few minor math and computing classes too.
When I went to do my master's degree
they were a lot more focused on
volcanology and geology and studying
past environments, and my research was on
Ngauruhoe in New Zealand,
which is actually Mount Doom in Lord of
the Rings if you're a Lord of the Rings
fan, and my PhD was looking at very
dangerous pyroclastic flows. So what that is is it's a really hot, really
really fast avalanche that races down a volcano, and
they go at speeds that you can't outrun
them usually, you can get real slow ones
but not very often, and they're extremely
dangerous. So the implications of
researching these is the more that we
can understand them the more that we
hope to be able to figure out where they
might go when they happen, and give
people warning. So understanding how pyroclastic flows and other volcanic processes
actually work means we can do things
like hazard maps, that's a map where you
can see where past eruption products
have gone. You can see a geologic map
behind me here of the Three Sisters
volcanoes in Oregon. But you can give
warning zones and tell people that are
in those warning zones what the signs
might be and how to get out of those if
they have any warning.
So Volcanology is a really really fun
field to be in but there's also a huge
serious side, and that is warning people
of the potential dangers around
volcanoes and that's not just people who
live around them that's also people who
actually visit volcanoes, so people who
might not have ever seen a volcano
before or know much about them. So if
someone in Florida, for you guys in
Florida, were to visit a volcano like Fuego in Guatemala or Kilauea in
Hawaii, even though that seems to have paused for now, or any of the other 1,400
potentially active volcanoes around the
world, it's important for you to know
what those dangers are. Hi Southwest
Florida home schoolers you guys can
start asking questions in the questions
comments below, I have a list of
questions that have already been
submitted but I'll
flip between those and try to get to all
of the questions so welcome. So a
question from Annie Cats is how do you
study volcanoes, how do you study if they
could erupt at any moment, and do you
have to wear special equipment? So a good
question Annie, and sometimes we can give warning about volcanoes when they might
erupt. We don't really predict eruptions so a
prediction is saying that a volcano is
going to erupt at this time on this day
and it's going to be this big but that's
incredibly difficult because a volcano,
especially when its leading to an
eruption potentially, is a constantly
changing system so you have magma that's
rising up through the rock below a volcano
it's breaking rock as it's going 
it's releasing gases, magma is really really
gassy stuff, it can be causing the
shape of the volcano to slightly change
very very slightly but we can still pick
that up and all of these different
things give us signals, so it's signaling
that magma is moving or fluids and it's
up to scientists, volcanologists, to use
the best technology we can, to use all of
the expertise across different aspects
of Volcanology to try and figure out
what that means and what it might mean
for communities around the volcanoes. So
to study volcanoes you need all of these
different technological aspects. You
have different technologies to study the
gas, to study the chemistry of water and
gas coming out of the volcanoes, to study
the seismicity, or the earthquakes, so
that's caused by that magma when it's
wedging its way up it's actually
breaking rock but the signal of the
magma itself moving can produce these
tiny tiny little earthquakes as well so
there's a lot of physics and processing
that goes into those. Alissa asks did
the mountains around the world start as
volcanoes? No, not all of them,
there are also mountains that have
formed by processes like tectonic plates
pushing together and actually pushing
mountain ranges up as well and then
there are some different processes like
the tectonic plates that go a little
more sideways and some actually pull
apart in different areas as well so
there are a lot of different
aspects of mountain formation around the
world and Volcanology is one area of
that which is incredibly complicated.
We have a question from Christ the
King School how do you determine how old a volcano is? Good question and that
depends on how old the volcano is so a
volcano produces a lot of different
eruption products and it depends on the
chemistry of the magma, what kind of
magma there is, the chemistry of the
gases, how much gases there are. So a lot
of you might have seen the lava flows at
Kilauea in Hawaii recently and let me
know if you are watching that, that was
an incredible eruption plus and also
awful to watch because of how many
people were affected so that's one end
of the spectrum we have really runny
runny lava flows that can flow very
quickly all the way to the ocean
depending on where the volcano is and
with other volcanoes you can have more
explosive eruptions. So a lot of you were
probably not around for the 
Mount St. Helens eruption in 1980 but
there is some incredible footage on
YouTube if you want to check that out at
some point and that's when you have more
of a sticky magma. So magma it's still
pretty hard compared to say honey or
peanut butter but those runnier lava
flow is at Kilauea that's your really
runny lava and when the chemistry
changes so primarily when you have more
of, more silica in the magma then it can
get a lot stickier so the stickiness or
the viscosity is one really important
factor and the other is the gas. So if
you think of having a bottle of Coke and
you know there's gas in it before you
open it but you can't see it before
you've opened the bottle for the first
time, that's because in the factory they've put
that under pressure so that the gas is
inside the liquid so if you open that up
you hear that that first sound and a lot
of the bubbles start to come out because
the pressures been reduced so if you
were to slowly pour that out then you'd
have more of an effusive Coke or soda
eruption but if you were to shake that
up you're going to have a buildup of gases
and pressure in that bottle and when you
open it up those bubbles are coming out
and expanding and exploding so quickly
that you have a mess of Coke foam
everywhere.
Well explosive volcanic eruptions are
kind of like that, you have a lot of gas
and when you have a lot of gas building
a lot of pressure and it can't escape
easily because the magma is really
sticky or viscous holding that together
then you can get a really explosive
eruption. So looking at these different
types of deposits you can look at the
minerals and the chemistry of them using
different techniques in the laboratory
to determine how old those volcanoes are.
So I kind of answered a few different
questions there, so we have how do
volcanoes erupt
which is the gases and viscosity
depending on those as well as how fast
magma is coming up. Magma can actually
come up pretty fast from quite deep
below the earth and there's also a
question there about how many types of
volcanoes are there. So it depends on how
you want to look at it but some of the
main types, you have our shield volcanoes
so that's like the one in Hawaii
those are really broad shaping so broad that
usually you can't actually see the slope
when you're standing on them that's
because the lavas are so runny that they
run quite far away from the vent, then
you can have the beautiful stratovolcanoes 
which are the beautiful peaks
that most people think of when they
think of a volcano or if you draw a
volcano that's normally what people draw
and those are built up from different
layers of lava and ash and volcanic rock
that are deposited through either days
or sometimes hundreds or millions of
years depending on how old the volcano
is or how big it is, and there are
caldera volcanoes which are volcanoes
that they can start out flat, sometimes they
can start out like a normal volcano shape
or "normal" volcano shape and that's when
you have so much magma erupting that
there's kind of a void left under the
volcano and part of it collapses so
those can sometimes form extremely large
eruptions but a really important note is
that the larger the eruption the more
rare it is so right now today do you
guys have any guesses about how many
volcanoes
there are erupting around the world
today? I'd love you to put in your number
of your guess and I'll keep talking and
then we'll talk about how many there are
erupting today. So at any given day you
have a certain amount — good question
the best place to for a volcanologist if you want to eat good pizza
Italy definitely Italy a few of us, 800
of us have just been to a conference in
Italy go to Italy if you want good pizza. 
We have some good guesses coming in
we have thirty, seventeen, a thousand, ten,
fifty, a hundred, so it's 41. The number of
volcanoes producing some kind of
activity around the world today is 41
and most of those are quite small so
most of the volcanic activity around the
world is a lot smaller because it's
easier to get smaller amounts of magma
to erupt then it is to get really really
big amounts of magma to erupt so if you
have a magma chamber or reservoir it's
not that ball of magma you see in most
drawings it's actually a network of
spaces, not spaces, they're not gaps, but
bits of melt and crystals and rock and
to get the melt together in one place
can be difficult and so once you have
enough of that in one place mixed with
rock and crystals you have "eruptable"
magma, that is magma that can actually
erupt but there's a lot of it that
doesn't so if you think of how many
granite building materials you see
granite kitchen tops in your kitchen
granite sidewalks, sometimes granite
buildings
all of that is magma chambers that never
erupted, it's the failed hopes and dreams
of a potential volcano. So there's a lot
of magma that never actually erupts and
sometimes the magma will get right up
inside a volcano and then stop so that's
another really big challenge when it
comes to monitoring these volcanoes is
sometimes you can have eruptions which
look like they're about to go and they
can be a huge danger to a lot of people
and then they just stop, they just run
out of steam, run out of fuel and then
they don't erupt and then it's a danger
for quite a while you don't know if
that's going to keep going
or if it's stopped altogether.
So there's a good question
there from Michelle. Isaiah asked how high
can magma shoot into the sky? So that's
a good question, it's a fun one. So
when you have a really really big
eruption, now remember the bigger the
eruption the more rare the eruption, but
occasionally we do have extremely
explosive eruptions and the biggest we
have are called Plinian and Ultra-Plinian
so these really big ones can
get tens of kilometers into the air 
So if you think back to that bottle of Coke
analogy, if you shake the bottle up and
then take the cap off and release that
pressure really quickly
all of that gas wants to come out at
once and that produces a jet which
throws the magma or explodes the magma
all the way up into the atmosphere and
that can get sometimes sometimes over 50
kilometers into the atmosphere, so very
very high, and that's when you can have a
lot of problems for things like air
travel, for example, we all saw the Icelandic
eruption that caused havoc with
European air travel over a few days
It can also produce ash fall, so that ash
which is ground up bits of rock, glass,
and crystals so it can be pretty nasty
stuff especially if you already have
breathing issues like asthma, over
tens or hundreds of kilometers away so
that can go across multiple countries or
even continents and oceans but normally
they're not that big. So normally they
can get around a few kilometers that's
what I normally say when you have these
smaller eruptions. So there's a good
question. Jaden asked when magma shoots so high how does it not get cold enough
from the clouds of snow to not stop it or freeze it? 
Well actually sometimes
you do get freezing as well so you can
get gasses and sometimes liquids
that build up in tiny little droplets
and those can freeze so this can also
locally affect weather, you can get water
droplets forming around it, you can also
get volcanic lightning which is a really
cool area of studying volcanoes, but
normally when you're getting really
really high those bits of ash are really
really small so the bigger particles or
rocks, they can be the size of a car or
much larger, they'll fall around closer
to the vent but once you start getting
kilometers away from the volcano
especially with those really high
heights you're going to get a lot of gas
or liquid droplets as well as tiny
little bits of dust and of course when
you get that higher they will freeze so
it's a good question and that actually
does happen. S o I'm going to go on to one
of the other questions I got over here
from Izzy Cats.
What is hotter, the sun or a volcano?
So volcanoes — also got another
question about temperatures as well, I'm sorry,  I can't see the name right now, but
volcanoes can get pretty freaking hot 
So usually they're a few hundred degrees
hot so I'm gonna talk in Celsius I'm
sorry you might need to change that over
to Fahrenheit but normally you can have
lavas which are erupting the more sticky
colder ones are at least around 700, 800
degrees Celsius. When you get the Kilauea
lavas those really red hot, yellow
orange hots lavas, those are around 1200
degrees so 1,200 degrees Celsius but the
Sun is about five-and-a-half thousand
degrees Celsius so the surface of the
Sun is definitely hotter than volcanoes.
I have a question here from Chelsea Kirk
what made you want to study volcanoes? I
mentioned before I always loved volcanoes, but you know we all love things we
don't necessarily want to study so I'm
driven by wanting to help understand how
volcanoes work and especially the really
dangerous eruptions that produce those
pyroclastic flows I mentioned. In my
career it's really important to me that
I work towards helping people, so helping
communities that live around volcanoes
I love communicating about volcanoes
especially on social media and working
with the media to make sure that the
right information is getting out there
because that can be life-saving if
someone has the right information at the
right time. So just the sheer love of
volcanoes, wanting to help understand them better
so actually doing scientific
research on their products and eruptions
and helping communities and helping
people who travel to volcanoes who might
not know where to get the latest
information. I have a question here
Do I have a favorite volcano and
if yes, why? Actually I have two and I've managed
to study both of them 
So the first volcano I kind of fell in love with was
Ngauruhoe volcano in New Zealand
It's a beautiful cone volcano in the
North Island of New Zealand and I
remember just staring at that volcano
when I was really little thinking it's
just amazing and that it's way too cool to
be a real job and I ended up studying
that volcano for my master's degree so
that was my first project which was one
of my dream projects and my second was
Mount St. Helens in Washington in the
United States. I grew up reading
everything I could about that volcano
and it's not only the volcano itself but
the stories of the people.
So leading up to the 1980 eruption there were a few
months of warning signs the volcano was
changing in shape as magma was going up
into the volcano
and there were a lot of different
earthquakes and people had to evacuate
and this was one of the first times or
the first time in the United States
especially that we had this potentially
very deadly and dangerous volcano
potentially leading to an eruption so
reading and learning about how people
reacted to the messaging and how people
reacted to having to leave their homes
is really important and understanding
how we can help people in the future.
Chelsey Kirk has asked how do you know
if a volcano is dormant?
So there's a
couple of different terminologies that
we use, we use dormant which is a volcano
that's been active within about
the last 12,000 years and that's pretty
young for a volcano so for us 12,000
might seem like a really long time but
for a volcano they can be millions or
hundreds of millions of years old so
12,000 years is really short when you're
talking about geologic time. So if
they're around 12,000 years or younger
we call them young volcanoes, these
of all cannons that could potentially
erupt again any time soon and there are
over 1400 of them around the world.
Once you get older than that, with
some exceptions, normally we'll call those
extinct and that's if there's no longer
a chance of that volcano erupting again
so this can mean that
so the tectonic setting might have
changed so much there's no longer a
magma supply for that volcanic system
but there's nothing that can feed that
volcano anymore. So looking at the past
activity of a volcano is the best way to
determine that and dating those ages, the
ages of the different rocks around the
volcano that were erupted to see when
the last eruptions were and how
frequently they erupted so that's a
whole area of Volcanology which is
pretty cool and there are a lot of great
scientists working on that. Michelle has
asked have I ever visited Crater Lake?
Best volcano aftermath ever. That's a
pretty impressive volcano and I have not
been there yet and it's one I really really
want to get to. So for those of you who
don't know Crater Lake that's a volcano
over in Oregon and it was Mount Mazama
which was a big volcano and it had a
huge eruption over a thousand years ago
I think seven point seven thousand years
ago that actually removed the top of the
volcano and cause that caldera collapse
I mentioned and so now there's a huge
lake, Crater Lake, at the top of that
volcano and for kilometers, tens,
hundreds of kilometers, around there are
explosive volcanic deposits that you can
go and see now. In fact this is a
different one this is the bishoped hoof
from a different volcano but this is the
kind of rock you get from these really
explosive volcanic eruptions they can be
so big and so hot that they can actually
weld together and all of those tiny
little bits of rock and ash form a solid
rock and this one actually turned pink
as well which is pretty cool pink rock 
Jayden asked if Everest was a
volcano and it erupted how big would the
blast be? So something I should have
mentioned at the beginning was pretty
much every question about volcanoes
usually starts with it depends. It's so
complicated there is so much we know
about volcanoes but there is so much
more that we don't know and
volcanologists around the world are
working really really hard to answer so
many more questions and think of new
questions to answer so that's a good
creative question. If Mount Everest
erupted how big would it be? And it
depends. It depends on what kind of magma
you had there if it was really gas rich
or gas poor so would you have lava flows
would you have big pyroclastic flows
these hot avalanches that race away from
the volcano. If it was like any other
volcano it would probably produce a lot
more smaller eruptions and then larger
eruptions but if it was capable of
producing larger eruptions then that
would definitely have something to worry—
we'd have something to worry about but
we don't because Everest is definitely
not a volcano but I like the creativity
in that one. What do we have here —
what is the tiniest volcano that has
ever erupted?
So there's another type of volcano
cinder cones
these are usually little cones, you can
normally walk up them within you know a
few minutes or a few tens of minutes
that are built of small bits of scoria
or rock that explode out of the volcano
and land around the vents and these
usually are quite small you can
sometimes get fields where you have tens
to hundreds of these little scoria cones
and one of the best recent examples of
this Parícutin in Mexico. So this
volcano over the last I can't remember
the date off the top of my head someone, anyone in the
questions give me the date of Parícutin
this produced a volcano in a poor
farmer's field so one day there was no
volcano and then you had this community
watching this volcano grow in the middle
of a farmer's field so that's quite,
that's one of the younger small
volcanoes that have formed and it was
actually well-documented too 
so there are plenty of those kind of volcanoes
and the smaller ones if you go to other
well-known volcanoes too so you can
often get a volcano which has a lot of
smaller volcanoes around it or on the
vents, sorry on the flanks of that
volcano - and you see a lot of these in
Oregon and other places like Washington
and some in California as well
Jasmine asked can volcanoes be under the
ocean? Yes in fact the majority of
volcanic activity on this planet is
under the ocean and there's a lot
that we don't know about it because it's
so hard to get to so like we said
earlier 41 volcanoes erupting on land. I
actually have no idea how many volcanoes
or volcanic systems are acting under the
ocean
I just don't know so there's an area of
research if any of you want to grow up
and be volcanologists although there are
plenty of things we don't know yet and
We have how many questions — how many
volcanoes have I been to? I don't
actually know the number but I've been
to Batur volcano in Bali, Indonesia
I've seen Agung from a distance
Plenty of volcanoes in New Zealand, we
have some quite young volcanoes there in
fact we have a volcanic field in New
Zealand where our biggest city is built
right on top of it so that's a danger
for if something erupts in the future.
I've been to Sakurajima volcano in
Japan, that's a very active volcano which
when it is erupting erupts quite
frequently so small ash plumes sometimes
multiple times a day and that was the
first volcano I saw erupt so I actually have
two cats, two kitties, one of them is
called Sakura after that volcano. I've
been to several volcanoes in Kamchatka
in Russia and my PhD fieldwork was on Shiveluch which is a very active very
explosive dangerous volcano in Northern
Kamchatka
luckily very remote and then plenty of
volcanoes in the United States so
Mount St. Helens, Mount Hood, Three Sisters volcanoes oh goodness
there are so many more I need to go and
see. Mono domes in California. Did you guys
know that there's a lot of volcanoes in
California as well? In fact there's a
California volcano observatory. I've just
been to Italy, I got back last week so I
went to Vesuvius volcano, Campi Flegrei which is a big caldera volcano
over there and I spent a week around
Etna volcano which has been erupting
for a very very very long time and one
of the questions I got previously was
how long do volcanoes erupt?
And that also depends, sometimes you can have an
eruption that'll last several hours and
sometimes you can have a volcano that
last decades so Kilauea was erupting
for over, has been erupting for over 30
years so we'll see if this eruption now
has stopped, keep an eye on USGS
for more information on that, and
then you can have volcanoes that erupt
for hundreds of years or thousands 
So hundreds of years like Etna volcano in
Italy or Stromboli volcano in Italy
and there are multiple other volcanoes
like that as well. Gabe asked what
volcanoes are in national parks? Good
question, so volcanoes in national parks
are volcanoes that I really like because
usually that means that there aren't
that many people living around them so
there's less of a threat to human life
of course there are animals that are
living in those areas which I do care
about as well but in the United States
for example you have Mount St. Helens
which is in a state park and
Yellowstone which is in a national park
you have oh goodness, now I'm going blank
on all the national parks in the US but
there are some amazing national parks
that have incredible volcanoes and some
of them young as well. What kind of
job opportunities do volcanologists have, and are there many jobs? Not enough jobs!
in fact my job that I have now is ending
in three months and I have no idea what
I'm doing after that but it's a field
full of incredible people you know we
all have our different areas in life
that we could call say we're "intelligent
with" you could be a genius and baking or
music or art or math or physics or
anything that you choose to do to
follow your passion and in Volcanology
we're very diverse as well. So I study
volcanic rock, I would like to get into
volcano monitoring and looking at
hazards, I do a lot of communication work
There are— a really important aspect is the
social science aspect of volcanology
so how can we communicate to people how are they affected by these processes and
how can we be better and informing
people what's going to happen and
there's computer modeling, there's the
physics of volcanic processes, there's,
you can do math, you can do chemistry, you can look at crystals within rocks, so
volcanic rocks actually have a lot of
crystals or minerals you can see some
really big ones in this one here from
New Zealand and you can go out and you
can do mapping, which you can actually go
into the field and physically map
them, you can use remote sensing so using
satellites and that's part of what I did
for my PhD, you can look at gas, you can
specialize in understanding earthquakes
and how to monitor them and track them
and understand what they mean and you
can also use your imagination and come
up with new things that we haven't
thought of yet. It's really important
for you guys to know going forward that
you know there's plenty of things that
we don't know and there's things that we
don't know that we don't know yet and
it's up to the people that are entering
the field and that will enter the field
later to come up with those new ideas
Creativity is really important in
science, it's important to think of new
questions so that you can get new data
and come up with new answers
Judith has asked what volcano have I
visited most recently? That would be
Etna volcano in Italy, so that's a volcano there that is active, it's producing
little puffs of ash every— this one was
doing it multiple times per day and I
was there just two weeks ago so that's
my most recent volcano. Chelsie Kirk has
asked what country has the most
volcanoes? There's a few countries with a
lot of volcanoes. I mean hundreds. So the
United States has 169 young, remember we
spoke about how younger volcanoes can
be more likely to erupt,
so 169 young volcanic centers. That's a
lot. Japan has a lot of volcanoes too
The Philippines, New Zealand has a lot,
Indonesia probably has I think the most
I might be corrected on that one as well
but basically there's an area you might
have heard of the Pacific Rim of fire or
Ring of Fire and that's an area where
the Pacific plate is subducting below
other plates, which is a really good way
to generate magma so all of the
countries around that are very active so
that includes Japan, Kamchatka, all
the way around the United States, Mexico
Chile, and all the way back down through
Pacific Islands, New Zealand, then we have
off the side, we have Indonesia and Papua
New Guinea. So there are a plenty of
very volcanically active countries. 
Oh it is really good to have
these questions, I'm sorry I'm trying to
read them as they're going, these
are fantastic questions.
Has a shield volcano ever
erupted? Yes in fact that's what Kilauea
was just doing up until— what was that a
month or two ago? And there are others as
well but I am blanking on what those
are right now so maybe I'll think of
another in a few minutes. We have a
question here.
Are there any volcanoes, this is from Max
Katz, that have erupted in both ice and
fire or snow outside? Yes
and when volcanoes have snow on them so there are plenty of countries that have
icy volcanoes
I mean the United States Rainier up at
the top of Washington state is a really
good example and these have— I'm
really interested in these because these
have a specific hazard which is very
dangerous. So if you think of a beautiful
snowcapped volcano that has all this ice
and snow on it, what happens when snow
melts? We have water. So if you have an
eruption that produces hot material
under the flanks of a volcano
this can cause ice and snow to melt very
rapidly and this can form these very
deadly very dangerous mud flows that we
call lahars and these lahars can be
incredibly quick they can raise the
level of rivers very rapidly in fact it
might look like there might be a wall of
water and rock and mud and trees and
anything else that they pick up in their
path coming towards you so monitoring
trying to understand where lahars have
been in the past at volcanoes like
Rainier is really crucial to
understanding which areas need to be
prepared for potential future lahars and
in fact there's a town of Orting in
Washington that does annual evacuation
drills so they get all the schools to
evacuate and walk up out of the danger
area and that is the kind of preparation
that people should really be thinking
about if you live near a volcano so
there are plenty of volcanoes in Iceland
which are covered in ice as well and
they can cause water and ice
interactions which can actually make the
the eruption a little more or a lot more
explosive because you have this water
flashing to steam and when water goes to
steam it expands a lot it's the,
the volume is
much much bigger of a gas than it is a
liquid or a solid so this can cause much
larger explosions and it can blow
the volcanic ash to much smaller
pieces and that's one of the reasons why
the Eyjafjallajökull eruption affected
the airspace over Europe and I apologize
for any Icelandic people watching this
for me butchering that word right
now. Jessica's asked what was the most
active / dangerous volcano I have ever
been to? Good question. There's several
ways to think of the most dangerous and
one of them is the largest or larger
eruptions but when I think of dangerous
I think of how it impacts people and
there are two ways of thinking about
that
so has it impacted people in the past
and have people actually being hurt or
killed or affected around a volcano or
are there a lot of people living around
a volcano now which could be affected in
the future so that would be Mount Rainier
in Washington a lot of people could be
affected by a volcanic eruption there
the most dangerous in terms of past
danger that I've been would be the
Mount St. Helens, I worked on their 1980
eruption as part of my PhD and that
killed 57 people so that was a
devastating eruption in fact we lost a
volcanologist David Johnson in that
eruption as well. In terms of the most
active that would be Etna volcano in
Italy that I was just at & Sakurajima
volcano in Japan, those will be the two
most active volcanoes I have been to
Gina asked is there a volcano in every
country? No but there are many many
many countries around the world that
have volcanoes and active volcanoes so
not all of them but quite a lot. Looking
through these questions again I have
these other one. Are there volcanoes in
Australia? Yes there are! I lived in
Australia for three years and not
working on volcanoes at the time, but
there is the newer volcanic province in
Southeast Australia near the city of
Melbourne I believe and that last
erupted around 5,000 years ago and
that means that it could one day erupt
again so there is work being done to
understand what the dangers could be and
what people can do to help mitigate or
help reduce those dangers in the future
so there's that people side of
volcanology again, volcanology where we just had
this conference in Italy which was
cities on volcanoes and there were
around 800 volcanologist at this
conference as well as emergency managers
people who are involved in teaching
people who are involved in planning, town
planning, and people from disaster
agencies, all of us coming together to
talk about places, the area of
research where people and volcanoes
interact so understanding the volcanoes
and the people side of it is incredibly
important especially around these
potentially dangerous deadly and active
volcanoes. Michelle has asked how many
volcanoes are in America? In the United
States I'm not sure of the total number
of top of my head but 169 centers so
there could be multiple volcanic vents
or cones in the center there are 169 of
those in the States and those states,
a lot of them are in Alaska, you have
Hawaii, Washington, Oregon, California,
Arizona, New Mexico, Idaho all that whole
area over there so there are a lot of
volcanoes in this country and you have
the United States Geological Survey
which is full of dedicated
volcanologists who work very hard to
understand all of these volcanoes and
understand how to keep people safe and
they're on social media too they have a
USGS volcanoes Twitter account plus a
Facebook page and they're always putting
out great information about different
volcanoes and current activity when
there is current activity. I have— did
I ever visit volcanoes in Iceland or did
I do research on those? No I have not
been to Iceland yet and that's kind of like
Disneyland for a volcanologist so I'll
definitely get to Iceland one day but I
have not been there yet them it's very
very high up on my list of places I want
to go Kiley asked how many volcanoes are
there in Oregon I'm not sure of the
actual number but you know what I'm
gonna give you a link quickly this is
where you can go for really good volcano
information it's the Smithsonian
Global Volcano Program and you
can search different volcanoes and
different keywords as well as get
updates on volcanic activity so I am
putting the link down there now that is
where you can go to learn about the
volcanoes that are currently erupting
around the world a lot of really good
work goes into weekly reports and
making sure that there are longer
reports of volcanoes that are erupting
around the world too so that's a great
resource that you guys can go play
around with. I'm going back to these
questions over here, are there anything
positive that results from having
volcanic eruptions? That's from Izzy Katz.
Yes very very good question, we actually
need volcanoes, we not only need
volcanoes because they're beautiful
places to live but they help give us
fertile soils. One of the reasons there
are so many people living in dangerous
areas around active volcanoes is that the
soil around volcanoes is very very
fertile so it grows a lot of crops
it's really great for farming, it's
really great for the growing food for us
and there's some places especially like
Indonesia and the Philippines, Japan and
other countries that have a lot
of volcanoes. Volcanoes also give us
building resources. So I lived in a
house that was made of blocks made out
of this stuff, very big pyroclastic
flow deposits or ignimbrite. They also
give us gravels for different materials too. They give us a lot of different
minerals, so diamonds come from a
specific kind of volcanoes which is
pretty cool, and really important
deposits like gold and precious metals
can be found around volcanic areas as
well, and even more importantly, a lot of
our atmosphere and a lot of our water come from volcanoes. So over millions and
millions and millions of years gases
that come out of volcanoes, this is part of
the normal system of our planet that's why
we have this beautiful atmosphere which
allows us to
live, as well as the water that we have
in our oceans and that we need to drink
so we do need volcanoes and there are
some theories that life revolved around
volcanic areas or geothermal areas as
well. Judith has asked, do volcanoes
contribute to global warming? The recent global climate change,
no. This is a question that comes up a lot
and it is a question that usually gets
some people very upset as well but no
We've been looking a lot at the amount
of gases that come out of volcanoes and
also the amount of volcanoes over time
in fact this year is actually so far
pretty low for the number of volcanoes
that have erupted compared to recent
years. So we can look at the history of
volcanoes through time, we can look at
the chemistry, the amount of eruptive
products and we can look at the amount
of gases that are released. This hasn't
really changed but the change that we do
see is attributed to what we are doing
as people. Now I'm not a climate
scientist so I'm not going to go any
further than that, that's not my area of
expertise but no they help give us our
atmosphere but they're not causing the
current warming or changing trends that
we see. Can anything be made from magma?
Yeah! Yeah a lot of rock that we see, I
mentioned earlier granite, beautiful
granite countertops, there are buildings
that I made from material that was
called magma that cooled under the earth,
so I'm gonna show you a couple rocks
here so this is a rock from Mount St.
Helens, in fact this is a bit of dome
rock that— sorry not dome, completely blanking on that word, cryptodome
so that was the hidden dome, that was the
magma that caused the eruption in 1980
so you can see here that it's gray and
you can see little black specks you
can't really see the white ones here
those are crystals in that so the longer
time that magma has time to cool, the
slower it cools the more the atoms within
that can move together and make
crystals then we see this one here you
see that it's kind of much bigger one so
that crystal would have had more time to
form. Now if you have a magma reservoir
or magma body that doesn't erupt at all
and it just sits below the earth cooling
over you know I don't know how long it
takes to call a magma reservoir but
we'll say years or hundreds of years
then 100 percent of that can turn to
crystal and that's when you get these
beautiful granites and other different
rocks from different chemistries that we
can use for building materials so it's
very very useful. There is a question
here on Yellowstone and I'm gonna say
that for all Yellowstone questions
you guys should go to this link because
USGS has commonly asked questions and
they do a really great job of making
sure that people have the right
information so the USGS Yellowstone
questions go to that link that I just
put up there, it's volcanoes dot
USGS, that'll— that should help answer
your questions. What do we have now?
Gabrielle would like to know how does
magma form? Good question and there's a
lot of work that goes into understanding
that as well, a lot of really cool lab work
where people look at the individual
crystals and chemical components of
magma. So there are several different
ways, one of them is to add water to a
system and that doesn't really make
sense when I say it by itself but if you
think of oceanic plates subducting down
below a continental plate this rock that
subducting has a lot of water within its
chemical makeup of the rock and when you
have it going down into these great
pressures and temperatures that water is
slowly gonna start coming out and that
water rises and when water is added to
rock it actually lowers the temperature
needed for that rock to melt so this is
why we have so many volcanoes around
subduction zones like the west coast of
United States and that's because you
have little bits of magma that start
to melt and then they rise up because
they're less dense than the surrounding
rocks, if you think of pouring oil into
water the oil rises that's what magma
does, it rises up through the rock and
then eventually that can add together
and form a bigger body of magma and then
you can end up with an eruption or a
volcano. Other areas you have plates that
are moving apart and this reduces the
pressure of the rock below there, you can
decrease the melting temperature
that way too so if there's less pressure
on the rock the rock, the rock can more easily melt and that's in places like the East
African Rift, there's a lot of volcanism
there, some really interesting
different volcanism there as well
because that's where the continent is
actually pulling apart and creating a
thinner cap over that area which means
less pressure which means magma can meld
another one we have which you know I
don't fully understand I'm not sure how
well we understand them but we have
hotspots and that's what Kilauea volcano
is and that's where you have an
anomalously high temperature area which
can cause rock above that to melt and
then rise up to form these really active
volcanoes too so it's a really complicated
process and we can't see it but we can
do laboratory experiments and there are
some great labs around the world that
are doing laboratory experiments that
slowly heat up rocks to see what
actually happens when magma is melting
so if you guys want to get into
Volcanology there's a really cool area
of experimental Volcanology as well and
there are people like people at Buffalo
that actually blow stuff up
they bury dynamite in a very scientific
way where they write down everything
they do, they get all of these different
instruments and senses and then they
blow it up and see what happens and they
study every different aspect. There are
places like Syracuse which actually make
their own lava and then they pour the
lava over different substrates and
measure everything that happens to it to
understand what lava does and there
is even a place in Germany that is
looking at different aspects of melts
too and there other places around the
world and there's even a huge flume that
USGS has where they they allow material
to run down and they look at how that's
flowing so experiments is another really
cool way to understand volcanoes too.
Oh, Daniel has asked a really good question.
Is there any volcano around I really
fear in terms of damage or tragedies if
it erupts? Yes there are plenty of them
So I decided I was going to be a
volcanologist when I was 13 years old that
was about two decades ago and it has never
ever got easier to see people getting
hurt by volcanoes, it is devastating
The recent eruption of Fuego volcano in
Guatemala where hundreds, potentially
more, have been killed by pyroclastic flows
is, is gut-wrenching, it's incredibly
difficult to see, so when I see people
living around volcanoes, which is all
around the world, it is scary especially
when they don't have a plan, when they're
not educating themselves on what the
volcano might do there are a lot of
volcanoes that we haven't studied
because there are a limited amount of
volcanologists and in order to do this
we need funding, we need money to study
these volcanoes. Like I said there are
over 1,400 potentially active volcanism
around the world and that's a lot of
work, so we're working incredibly hard to
understand specific volcanoes because
every volcano is different, just like us
they have their own personalities which
means before they erupt they're going
to have their own different style of
warning signals they give us so it's not
like you can look at one volcano and
understand it really well and and say
these different signals usually mean
that this eruption is going to happen
and then apply to another volcano, it can
help, it can definitely help but it's not
going to be the same. For example Agung
volcano in Bali in Indonesia twelve
months ago was showing very very high
activity for two months before it
erupted and then you can have some
volcanoes which give days to weeks of
warning so they're all different and
thinking of people not knowing what to
do and not knowing where to get the
official information, so the information
from the volcano observatories or the
disaster agencies, and people not knowing
what to do, so for example if you have a
lahar or a mud flow coming down a valley
get out of that valley, if you hear a
strange noise or feel a rumbling you've
got to get out, if you are in an area
which might be prone to pyroclastic
flows knowing that if you see a grey
cloud get out of the way, knowing that
there are millions of people around the
world who live near dangerous volcanoes
does scare me and that is something that
I'm going to work with colleagues around
world for the rest of my life to try
and improve. So very good question. How
long have I been studying volcanoes? So I
have a bachelor's degree, which is three
years, and master's degree, which was two
years, I got professional experience
outside of Volcanology for family
reasons actually, I moved to Australia
for three years, my PhD was five years
and I finished my PhD a year ago
and I think getting experience working
on volcanic ash, a volcanic ash project
as well as communication stuff for that
so I've been reading about volcanoes and
learning as much as I can for around 20
years now
but actually working on them I did not
count as I was saying those numbers but
you can add those up. So how long does it
take for magma to get hard? I don't know!
Good question. When it's under the
earth—so as you go deeper below the
earth the pressures are greater and the
temperatures are hotter and it would
depend on how deep it was how much magma
there is. So for example lava flows on
the surface of the earth you can have a
lava flow it just really thin that can
cool in hours or a few days or you could
have lava flows which are really really
thick so lava flows can get over tens of
meters thick sometimes over 20 meters
depending on how sticky or viscous they
are or how far they manage to flow or if
they get pondered or pulled within a
depression that can take years or
decades so I would imagine that magma
cooling below the surface could take
maybe as a pure guess hundreds or
thousands of years but good question, I
don't know.
Delanie asked how do you get the rocks?
Do they break off or do you break them
off? Good question. So we often go into
the fields into an area that you're
interested in and an important part of
that is collecting samples but it's
really important to be respectful of
that environment especially if you're
working in a national park you often
need permits to collect samples so
getting them from the ground would be
ideal because then you're not breaking
any rocks you're not causing any damage
to that area
but sometimes you need to know exactly
where that rock came from or what
orientation the rock was in before you
broke it off so in that case we use rock
hammers and sometimes sledgehammers to
break those off and it's really
important to protect your eyes when
you're doing that because little shards
of rock and glass can go flying and that
can be a little dangerous at times
you might have seen some really cool footage
of some people collecting actual lava
in the Kilauea eruption if you look on
YouTube USGS collecting lava I'm sure
you'll find it but that's when they're
collecting and when it's still hot, still
molten, still runny and that's important
because as the lava cools down you have
crystals growing and that's going to
change the lava you want to see what
it's like as it's hot and as it's
running because that helps us to
understand the volcano and how it's
changing over time so there are a few
different ways but generally hopefully
the way that's not causing damage to the
environment and being respectful to that
there are people who live around
volcanoes and plenty of people who
travel to them so you've always got to
be respectful and make sure you're not
doing any harm to the environment.
Beside the volcanoes you scare are there
any specific volcano you love and
probably know nearly everything about it?
There is no volcano in the world that I
know nearly everything about. There are
some people who spend decades of their
career studying one volcano
understanding every different aspect
about that one volcano and what their
volcanic eruptions have done in the past
and those people are so useful and there
are people like me who studied different
volcanoes and different aspects of
volcanoes to look at the bigger picture
of hazards, so what the dangers are and
how they might affect people and that's
the work I want to get to in the future
so I've studied specific eruptions, on
Shiveluch volcano in Kamchatk,  I studied
eruptions from 2001 to 2017 so that was
over a few years but I do not know
everything about one volcano, they're
incredibly complicated, the eruptions
change through time, the chemistry can
change through time, they have many many
different eruptions through time so
usually there are many different
volcanologists that know different 
parts about volcanoes and that's
where it's important for us to work
together and collaborate so that all of
us can come together to better
understand that system so that we can
help communities that live around them
let me see back to over here, it's a
really interesting question. Alexander
Evergreen asks if the sassy Cascade
volcanoes could have a one-on-one group
talk with Krakatoa in Indonesia how would
that conversation probably go? You know I
don't know but Krakatoa is pretty
active right now. Krakatoa is a  really
interesting volcano, so in 1883 it
produced a very very large eruption
which killed tens of thousands of people
it actually collapsed into the ocean
causing a tsunami, it caused huge pyroclastic
flows and really distributed ash fall
over a very very very large area but
like I said those big eruptions are
pretty rare so since then it's been
growing what is called Anak Krakatoa
which is baby Krakatoa so it has this
relatively small beautiful little cone
which is currently producing Strombolian
eruptions, which are eruptions that have
these gas explosions which throw out
really hot bits of hot rock and lava so
the personality has changed a little bit
if I was Krakatoa and talking to the
Cascades volcanoes I would warn them not
to do what I did and completely cause
the devastation of my cone, I would want
them to just be smaller and be a bit
more calm so I'm not hurting people but
I don't know good question I like the
creativity on that one as well. We
have over here how close can a person
get to a volcano without it being a
hazard? I'm gonna say that there is no
such thing because even when a volcano
is not erupting they can still be
dangerous and that is because volcanoes
can often be quite large and that means
that the weather around volcanoes can be
a hazard in itself and so you can have
volcanoes which are bigger, plenty of
these in Washington and Oregon, which you
can have storms come in very quickly so
the weather itself, exposure can be a
danger because these volcanoes are
composed largely of loose volcanic rock 
you can have landslides, especially if
you have things like heavy rainfall or
maybe even earthquakes in the area there
are different things that can cause
events to happen with no warning and you
can have lahars that form when there
are not— when there hasn't been
activity for hundreds of years, you can
also have parts of volcanoes collapsing
when the volcano hasn't been active for
a long time either
so in a way volcanoes are always
dangerous but it's about really
understanding what those dangers are and
making sure that you're not in the
worst-affected, potentially affected
areas, but when it comes to an erupting
volcano it depends on what style the
eruption is so if it's a big eruption
that's producing a lot of pyroclastic
flows you really want to be tens or
even more kilometers or miles away from
that volcano, and if it's a volcanic
eruption producing a lot of ash it
depends on the wind direction so
volcanic ash plumes, most of them at
least, are really influenced by the
direction and the speed or strength of
the wind, so you could have a town on
this side of the volcano which is not
being affected an ash fall that is
affecting everything on this side of the
volcano and while ash doesn't usually
you know kill you directly it can
definitely cause a lot of breathing
problems which can be quite dangerous
and if it's enough ash it can collapse
some kinds of rooms as well they can
also cause problems for technology for
vehicles so it's really bad with
airplanes another reason why it's so
important to monitor volcanoes even if
no one lives around them because you do
not want to be in an airplane going
through an ash plume it can actually
kill the engines and although so far
every engine that's been killed has
managed to— the pilots have got it
going again and no planes have actually
crashed but some of them have gone down
for a very long time or a long way
before that, so the best thing is just to
know really the local volcano
observatories and who's working on them
a lot of people put information on the
Internet so if you're going to
Washington or California check out USGS
or Oregon or Alaska or any other place
where you might have volcanoes they have
information and hazard maps so you can
actually go and see the dangerous areas
and what the specific danges for that
specific volcano actually is
so yeah you know do your homework and
it's fun, it's fun learning about these
different volcanoes. We have how hot
does the magma get? Down below the
surface I'm not sure but at the surface
which is probably the same thing we have
up to 1,200 degrees Celsius but it can
range from around I don't know six seven
eight hundred degrees Celsius up to 1200
degrees Celsius so your runny magma is
like the Kilauea lavas those are the
really really hot ones really runny and
then you can have volcanoes like Mount
St. Helens which are much more stickier
Magma's that would be maybe around 800
or 700 or 900 degrees Celsius so that's
the kind of temperature range you're
looking at the melted rock that's coming
out from the earth. So we're about out
of time thank you guys, there's so many
good questions I'm sorry I didn't get
around to answering all of them. One
more question here. Good question
Daniel. I saw you're often fighting about
fear mongering and wrong information
being spread about volcanoes, do you
expect that this is going to get even
worse in the next years? You know what
I'm kind of braced for it
I hope not and I think the more that we
work with media, and there are so many
excellent reporters out there doing an
amazing job who are getting in touch
with us because we are more on social
media we're more active and two-way
conversations with people, so people can
access us more so that fear-mongering
articles and news reports don't get out
as often but there are specific tabloids
and other things which are determined to
put out lies about volcanoes and so if
you see something that's really scary in
a headline go to the volcanologists you
know when we're on Twitter some of us
are on Facebook, there are the US– for
example in the States the USGS sites
they have an email you can contact but
you know it's really easy to get in
touch with them on Twitter or on
Facebook, just ask and see what we're
saying because our lives are dedicated
to helping people and that involves
people getting the right information
there is nothing we can gain from hiding
information that is
not what we do, there's no point in
hiding anything. In fact that goes
against everything that we believe in as
volcanologist trying to help society so
there are some really scary headlines
out there in the media, just know that
they're out there out there being scary
just to get your you to click on them so
that they get money from the ads on
their page. It's if it's really scary and
it's not backed up by volcanologists
warning you which is what we work to do
then just don't pay attention to it. So a
good question thank you guys so much,
thank you to Sarah for having me on
Skype A Scientist and I hope we'll be
back one day and I hope you guys have
learned a lot about volcanoes and I'm on
Twitter if you have any other questions
So thanks guys I'm gonna say goodbye and
I'll see you around on Twitter and
anything else. Bye!
