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GEONET NEWS
EXPLORING THE GEONET PROJECT
ISSUE 20 – NOVEMBER 2014
Social media and disaster information:
Lessons from New Zealand
New Zealand’s revised Volcanic Alert Level system
Hillary Ridge rock avalanche
Dart River / Te Horo landslide
Monitoring remote crater lakes from space
GEONET NEWS
EXPLORING THE GEONET PROJECT
INSIDE
INTRODUCTION
FEATURES
Social media and disaster
information:
Lessons from New Zealand
3
A volcano myth 4
New Zealand’s revised
Volcanic Alert Level system
5
Hillary Ridge rock avalanche
6
Dart River / Te Horo landslide
8
Dob in a landslide!
9
Monitoring remote crater
lakes from space
ISSUE 20 – NOVEMBER 2014
10
Cover image
The Dart River / Te Horo landslide
www.geonet.org.nz
The year is drawing to an end and it’s been another mixture
of hazards and events in New Zealand. We started off the
year with ‘a bang’ and the M6.2 earthquake in my hometown
of Eketahuna. We received over 9000 felt reports for this
event and there were multiple reports of damage. Following
the quake we published three possible future scenarios
and probabilities of what we expected to happen next.
This was a breakthrough in the presentation of earthquake
knowledge, and something we will continue to do with large
events, a wee look into the future!
It’s been a relatively quiet year in terms of volcanoes and
tsunami; although as previous years have shown this can
change in an instant and sometimes with little warning.
Dunedin’s M4.1 quake in October was a good reminder that
you can’t find a town in New Zealand without earthquakes.
The best we can do are a few places (including the top of the
North Island) that get them very infrequently, and this is life on
a plate boundary. The QuakeSearch tool on our website can be
very handy if you want to see how many earthquakes your area
has had over the years; it’s under the ‘Data’ tab.
For those of you with our GeoNet Quake smartphone app, there
has just been a new release with a great new look, and you are
now able to set up notifications for quakes in multiple areas.
GeoNet is a non-profit project operated by the
Institute of Geological & Nuclear Sciences Limited
(GNS Science) with core funding from the
Earthquake Commission. It involves GNS Science
building and operating a modern geological hazards
monitoring system for New Zealand.
The GeoNet project started in 2001. It provides
real-time monitoring and data collection for
rapid response to and research into earthquakes,
volcanic eruptions, tsunami and landslides.
Data collected by GeoNet are available free of charge.
Visit www.geonet.org.nz for more information.
2 – GEONET
Sara Page
Editor
SOCIAL MEDIA AND DISASTER INFORMATION:
LESSONS FROM NEW ZEALAND
Facebook
Blogger
GeoNet’s journey into social
media started off slowly and
a bit one sidedly. Twitter and
Facebook accounts were set
up and posts were made via
automatic RSS feeds of our
recent earthquakes and news.
There was a bit of interaction
on Facebook following the
2010 Chilean tsunami, where
members of the public were
asked to post feedback and
photos, but after this the page
was left to its own devices.
Shortly after the first earthquake in
Christchurch the public noticed the
GeoNet Facebook page and began
to ask questions and share their fears
and concerns. It was around this time
that I asked to take on the page and
began to answer the questions and
post information / pictures etc. and we
discovered the importance of social
media to get information out to large
numbers of people quickly.
Back at this time GeoNet had duty
officers on call who would manually
locate the earthquakes and it would take
around 20 minutes for the detailed event
information to get posted. Social media
allowed us to post comments such as
“Latest shake in ChCh will be posted
shortly – looks to be about 4.5”. This
gave the public some information and
helped them feel reassured to see that
we were busy working, and we would
have the information out as soon as
possible.
Facebook and Twitter have allowed
people to ask us questions, share
information / experiences and they also
give us vital information. Another great
thing is that they allow you to quickly
dispel rumours and misinformation, as
well as get important information out in
an instant. After talking with the
Queensland Police Department, which
has done fantastic things in social media,
I started doing some ‘Myth busting’.
This really helped during times of crisis,
as some really bizarre information can
come out, and because of social media,
spread quickly. One such myth was that,
following the earthquakes in Canterbury,
a volcano in the South Island was going
to erupt again. Luckily for all those in the
South Island all of the volcanic activity is
in the North Island!
Another great social media tool is
blogging. Blogs are a great way to give
science information a more personal
touch, and let people see a ‘behind the
scenes’ view of how things work. I
started my blog ‘GeoNet – Shaken not
stirred’ by following our rapid response
Twitter
team as they headed down to
Christchurch to install temporary
instruments (to better locate the many
aftershocks). It allowed the public to see
what we were doing in response to the
earthquakes, and to discover that we
were people too and not all old scientists
with socks and sandals (though we have
a few of those as well). My topics have
ranged from behind the scenes, out in
the field, to bizarre things we see on our
volcano cameras. My most popular blog
post, which ended up going ‘viral’ and
appearing on websites around the world,
was the Foo Fighters concert showing
up on our instruments.
The value of social media was again
shown during 2012 and 2013 when two of
our volcanoes were erupting. White Island,
our most active volcano, and Tongariro,
which hadn’t erupted since the 1800s,
both erupted in August 2012. Tongariro
erupted again in November and then it
was back to White Island which erupted
twice in 2013. We were able to get
information out quickly to many people
whilst the volcanologists worked on the
more detailed volcanic alert bulletins.
In this day and age people want
information ‘right now’ and social
media is helping us provide just that!
Contact: Sara Page
Email: [email protected]
GEONET – 3
A VOLCANO MYTH
White Island crater lake.
An urban myth that has been
around for many years is that
“White Island is the safety
valve for Auckland, Rotorua,
Taupo, Ruapehu etc…”
in the Daily Southern Cross newspaper
published on 5 July 1864. The letter is
from a Mr Walter Brodie, 20 years resident
in Auckland province, late member of the
House of Representatives, and J.P. of the
colony, and is dated 2 April, 1864.
When giving talks and presentations
on the ‘volcanic zone’ it is one question
or comment that frequently comes up,
the White Island safety valve! It comes
in many variations, but usually the
underlying theme is the same, ‘so long
as White Island is steaming all is good,
when it stops it’s time to worry’. I have
often wondered what the source is of
this great urban myth.
He is taking exception to the “removal
of the seat of Government from Auckland
to some place in Cook Straits … to
be more central”. He points out how
many capital cities are not central,
the high costs of a move, difficulty in
communications, not being in the centre
of the native population, shipping exports
etc. The weather also gets a mention
and then the focus moves to the effects
of the 1848 Marlborough earthquake
in Wellington and the more damaging
January 1855 Wairarapa earthquake.
Currently working on a project evaluating
past activity at White Island (Whakaari), I
came across this great letter to the editor
4 – GEONET
Towards the end of this he puts forward
this remarkable reason for Auckland not
having earthquakes, “The great safetyvalve against earthquakes in Auckland is
White Island, in the Bay of Plenty, which
volcano is always in action”. This may
well be the original source of this great
urban myth.
As we all know volcanoes and
earthquakes don’t quite work like this…
Contact: Brad Scott
Email: [email protected]
NEW ZEALAND’S REVISED VOLCANIC ALERT LEVEL SYSTEM
The New Zealand
Volcanic Alert Level
system defines the
current level of activity at
our volcanoes. A revised
Volcanic Alert Level
system that better meets
the needs of its users
became active in 2014.
Developments in volcano monitoring
over the past 20 years have created an
opportunity to improve the Volcanic Alert
Level system; these improvements in
volcano monitoring have come about
through the GeoNet project (funded by
EQC). The former Volcanic Alert Level
system was reviewed between 2010 and
2014 as part of a research project that
looked at improving the communication
of information about volcanic activity.
This research found that the system was
perceived to be too complex. Ways to
make the system more understandable
and useful were identified during
the revision process, leading to the
development of a ‘new’ Volcanic Alert
Level system, which is now in use.
A Volcanic Alert Level system was first
developed before the Ruapehu eruptions
in 1995, and has been in use since
then. It has been used for eruptions at
Ruapehu, White Island, Raoul Island
and Tongariro (Te Maari). Changes in
the new system include having just one
system for all volcanoes in New Zealand
(previously there were two), restructuring
the system so that there is an additional
level for ‘moderate to heightened
volcanic unrest’ (instead of just one level
for all volcanic unrest), and adding in
information about the most likely hazards
that will be seen for each level of volcanic
activity. The number of levels in the new
system remains unchanged, and ranges
from 0 (no volcanic unrest) to 5 (major
volcanic eruption).
Contact: Brad Scott
Email: [email protected]
GEONET – 5
HILLARY RIDGE ROCK AVALANCHE
A rock avalanche fell from New Zealand’s highest mountain, Aoraki/Mount
Cook (3724 m) on the evening of 14 July 2014. Forming a fluid-like flow,
debris spread down the Noeline Glacier and onto Hooker Glacier sweeping
a path area of 2.1 km2. Debris was first noticed by helicopter pilot
Jim Campbell on 15 July, although the event was possibly heard in Aoraki/
Mt Cook village. The GeoNet seismograph network also picked up the
avalanche, and this has been recorded as a magnitude 2.6 landslide event
with 0km depth.
Aerial view of Gardiner Hut which escaped complete destruction due to its location on top of the snow covered Pudding Rock – a local topographic high.
Photo: J. Spencer, DoC
6 – GEONET
This event was culturally significant to
New Zealand as it fell from the sacred
(topuni) area of Aoraki/Mt Cook that is
of special significance to the local Ma-ori
tribe Te Ru-nanga o Nga-i Tahu, as well
as being a collapse from Hillary Ridge
– named after New Zealand’s national
hero Sir Edmund Hillary.
An immediate investigation by the
Department of Conservation (DoC)
showed that Gardiner Hut, a small
mountaineering shelter, lay within the
avalanche path but had somehow
avoided complete destruction, though it
was partly buried by rock and ice, and
slightly deformed due to burial weight
and projectile rock damage. A separate
toilet shelter was smashed against the
end of the hut and damaged beyond
repair. The hut was unoccupied at the
time and was immediately closed to
further use.
GNS Science made an aerial inspection
of the avalanche on 16 July 2014,
observing and photographing the
debris, path and source area.
Subsequent mapping and observations
were carried out using historic and
recent photographs, aerial and satellite
imagery, and seismic records.
Rock avalanches have occurred
previously from Aoraki/Mount Cook; the
most well-known being a 12 million m3
collapse of the eastern summit area on
14 December 1991 which lowered the
mountain by about ten metres. Although
the avalanche occurred unexpectedly
and without any apparent trigger, these
events are to be expected and are a
major erosion process shaping ridge
crests and alpine summits in the
Southern Alps. They are also a
significant natural hazard in the region.
Contact: Simon Cox
Email: [email protected]
The response team taking photos from a helicopter.
Photo: D. Dittmer, DoC
Overview of the rock avalanche source area, path and deposits. View from near Hooker Glacier, looking upwards
towards the high peak of Aoraki/Mt Cook (3724 m left), low peak (3593 m) and south face (centre), and Hillary
Ridge and Nazomi peak (2925 m right). Gardiner Hut is annotated with a letter G. Photo: S. Cox, GNS Science
Close-up of the damaged Gardiner Hut.
Photo: J. Spencer, DoC
GEONET – 7
DART RIVER / TE HORO LANDSLIDE
The Dart River / Te Horo landslide.
Another example of the phenomenal erosion
that occurs in the Southern Alps is the Dart River
landslide. The landslide is in a sacred part of the
Mount Aspiring National Park, and is known as
Te Horo to local Ma-ori. It has been around for
thousands of years and has, over time, built up
a large fan in the Dart Valley.
The camera looking up at the landslide.
The Dart River / Te Horo landslide has
been moderately active for the last
few decades, but was reinvigorated
following heavy rain in January 2014.
Large amounts of rocks and soft mud
were washed down across the fan at the
bottom of the hill which then travelled
down and blocked the Dart River causing
a lake to form. Although the river is still
flowing through the debris, the landslide
continues to supply fresh rock and
mud that can only be carried away by
the river when it is in flood. The lake is
currently around 4 kilometres in length,
8 – GEONET
regularly rises and falls, and is expected
to become a feature in the landscape that
could take many decades to fill in.
As this ongoing event represented a rare
opportunity to study one of the most
active landslides in New Zealand, a
camera was installed in July. Photos are
taken every 15 minutes, or if movement is
detected, and the stored data is collected
every 3 months with a goal of creating
a time-lapse video of activity on the
landslide and interaction between the
Dart River and the fan.
The camera is strapped to a tree on the
bank of the Dart River, overlooking the
fan and up to the landslide, and it has
a solar panel to recharge the batteries.
Due to its remote location, and 5hr return
walk, a jetboat was used to ferry batteries
and install equipment.
Contact: Simon Cox
Email: [email protected]
DOB IN A LANDSLIDE!
Those who study landslides envy those who study earthquakes because
all earthquakes are automatically recorded via our large network of
instruments, while to find landslides we have to rely on human reporting,
and consequently miss many that occur.
Why do we record landslide information?
– It is so we can collect data to find when,
where and why landslides have occurred,
with a view to establishing the hazards
that landslides present to the safety of
people and infrastructure, and to mitigate
these hazards. We rely on news reports,
eye-witness accounts and the very few
landslides we might discover ourselves.
Obviously this gives us a very poorly
populated database on which to draw
valid conclusions, so the more people who
can inform us of landslides, the better.
How can you ‘dob in a landslide’? – email
us as much of the following as you can
supply, and we would be very grateful:
1. Date and time of event
2. Location – ideally GPS co-ordinates,
but a street address would suffice.
In areas without addresses, distance
from a landmark or intersection of
roads would be helpful. You could also
use Google Earth or maps and place a
virtual “push-pin” and send that to us.
3. Size – it would be useful to know if
one person could clear the landslide,
or if heavy machinery would be
needed. If you can get estimates of
the landslide’s width, length and height
without putting yourself in any danger,
that would also be useful.
4. Type – was the landslide made up of
rocks falling from a cliff, along a road
or an excavation for a building. Or
was it a flow of material rather than a
fall? Was anyone injured or anything
damaged? Anything at all you can tell
us would be gratefully received.
5. Photos – this would be very useful
for us, especially views showing the
whole landslide, and a wide enough
view to show its context within the
landscape. For emailing it’s best
to send a lower resolution image.
If you have movies of a landslide
actually occurring, we will see about
getting them from you while you
can retain full copyright and make
your fortune or just gain kudos on
Facebook if you manage to capture
something exceptionally interesting.
If we re-use your images, you will be
acknowledged in any publication we
might make.
6. Any other comments – possible
cause (heavy rain, earthquake,
incautious excavation etc). Feel free
to hazard a guess.
7. Your contact information – so we
can ensure your contributions are
properly acknowledged, and in case
we have any further questions about
what you submit.
GeoNet has a rapid response capability
for landslides in New Zealand. The team
investigates larger events that meet
certain criteria, including those that result
in death or serious injury, damage to
infrastructure or personal property to a
value of over $1 million, large economic
losses, threats to public health and those
of significant research interest. But this
does not mean we are not interested in
smaller events as well. Cumulatively,
hundreds of small landslides caused by
rain in a particular area can be just as
damaging as one mega-event.
Our team of eager landslide experts
awaits your kind contributions! Just send
them to us and don’t assume that
someone else would have told us before
you do.
You can send in your landslide emails
to: [email protected]
Contact: Nick Perrin
GEONET – 9
MONITORING REMOTE CRATER LAKES FROM SPACE
Close-up of the Landsat 8 image showing the
Ruapehu Crater Lake temperature.
Lake surface temperature vs Landsat 8 temperature
Lake surface temperature from Landsat 8’s Thermal Infra-red Sensor (TIRS). Cooler water surfaces appear
blue (for high altitude lakes) to cyan (Lake Taupo) while warmer waters appear as yellowish (northern end of
Lake Taupo) to red (the Ruapheu Crater Lake).
Many of our volcanic craters or calderas occupy
crater lakes which come in different sizes,
ranging from a few tens of metres to kilometres
across. These lakes provide good means to
monitor changes in the status of the volcano.
For example, some crater lakes have cold
water as they are filled by rain, but some
other lakes are warm or hot during the year
and remain connected to the volcanic
plumbing. The heat flow from a crater lake
is a good indicator of the behaviour of the
volcano. Any unusual rise in the lake
surface temperature or its level along with
discolouration of surface water, due to the
change in the concentration of suspended
particles within it, suggests a preliminary
stage of volcanic unrest and demands
careful and regular monitoring.
Some crater lakes are regularly monitored
but other lakes are very remote (off-shore
islands) and have difficult access or
hostile environments, thus limiting the
ability of volcanologists to capture regular
data to monitor their health/status.
10 – GEONET
Satellites offer a unique solution to this
problem. They revisit every part of the
globe at regular intervals and some can
record Earth’s surface temperature using
on-board thermal sensors. Landsat 8
satellite, launched on 11 Feb 2013,
records thermal images of the Earth from
a distance of 700 km and revisits the
same spot every 16 days; however,
overcast weather limits its imaging
capability. These images are useful to
monitor remote and inaccessible crater
lakes. The Earth’s atmosphere and high
concentration of water vapours above the
lake surface induce errors which require
processing and calibration of these
images using surface temperature values
of routinely monitored lakes such as
Ruapehu Crater Lake.
Graph comparing temperatures taken on land vs
satellite.
Landsat’s unique orbiting arrangement
and the peculiar positioning of Lake
Ruapehu allows the satellite to take two
images in its 16 day cycle. Regular
recording of a submerged thermal sensor
at the lake and correction of atmospheric
effect from thermal images helped in
calibrating temperature readings from
images to within ±2 °C. Micro-climate and
the presence of water vapours above the
lake surface during winter season show
greater differences between satellite and
ground values. After fine tuning and
careful calibration, space borne thermal
imaging will be applied to all off- and
on-shore crater lakes to improve volcano
monitoring and assessment.
Contact: Salman Ashraf
Email: [email protected]
PROFILES
COMING UP...
Emergency
Management Summer
Institute
When: 2-6 March 2015
Where: Wellington
Dave Whitelaw
GeoNet Field Technician
Sara McBride
Public Information Specialist
Dave joined GeoNet in June 2014 as a
field technician. His primary focus is on
the Nationwide ETNA strong-motion
upgrade programme that is planned over
the next 12 months.
Sara joined the GeoNet team in June 2014
as a Public Information Specialist and will
be with us until January 2015. She is
originally from Washington State, USA, but
immigrated to New Zealand in 2001. Her
work focuses on communicating with the
public and other groups about natural
hazards that GeoNet monitors.
Having lived on Raoul Island for close to
two years while working for DOC, Dave
became familiar with GeoNet and the
equipment we use. It was on Raoul Island
as the mechanic / jack of all trades where
he found himself alongside GeoNet staff
hanging off cliff faces installing cabling for
a tsunami gauge or climbing a radio mast
to confirm correct antenna alignment. And
then subsequently getting called upon by
GeoNet staff to go and check on or repair
equipment.
Dave has a background from the
automotive trade, both light petrol and
heavy diesel. Upon stumbling across a
field tech vacancy in GeoNet, Dave saw
an opportunity for a job he already knew
he would love. “It’s hard living on a
volcano for almost two years and not
want to be involved in the exciting work
that GeoNet is a part of”.
Dave is an avid skateboarder and can
often be spotted at the end of the day
across the road at the skate park.
Email: [email protected]
Sara, who previously worked at GNS
Science as a social science researcher, is a
Massey University PhD candidate, studying
the communications lessons learned from
the Canterbury earthquake sequence and
how we can communicate earthquake risk
more effectively. During the 22 February
2011 earthquake she was the Public
Information Manager Second in command
response, having previously worked as a
public education and information
coordinator at the Canterbury Civil Defence
and Emergency Management group and a
communications officer at Environment
Canterbury.
She has a Masters Degree in Public
Administration with a postgraduate
diploma in Disaster Management and
Humanitarian Assistance from the
University of Hawai’i, as well as a B.A.
in Law and Justice and a postgraduate
diploma in Public Relations. In her spare
time, if she has any, Sara can be found
ambling through the shoe shops of
Wellington for bargains on stilettos.
Contact:
Daryl Barton
[email protected]
CONNECT...
/geonetnz
@geonet
@geonet_above4
@geonet_above5
geonet-shakennotstirred.blogspot.co.nz/
geonet-scienceinaction.blogspot.co.nz/
geonet-dev.blogspot.co.nz/
Email: [email protected]
GEONET – 11
RECENT ADDITIONS TO THE NETWORK
Our regular wrap-up of the new stations added to the GeoNet
hazard monitoring network, constructed by our team of
technicians at Avalon, Wairakei and Christchurch.
Contact details
GeoNet website: www.geonet.org.nz
Email: [email protected]
Address: GNS Science, PO Box 30-368,
Lower Hutt 5040, New Zealand
Editor: Sara Page
March 2014
VGET
ETVZ
BOWS
GeoNet News is published twice yearly.
Additional copies are available, at no cost
for domestic delivery, from Leanne Dixon,
GeoNet Administration Coordinator
Email: [email protected]
Phone: +64 4 570 4888
East Tongariro a new cGPS and seismic
site for the Tongariro National Park
volcano seismic network
Articles published in this newsletter
may be quoted or reproduced as long as
GNS Science is acknowledged as the source.
GNS Science retains copyright on photographs,
diagrams and illustrations and reproduction may
only occur with prior written approval.
Bowen St Turnbull House Wellington
strong-motion station.
May 2014
HANM
Hanmer Basin cGPS
PGNE
North Egmont cGPS
TKHL
Takaka Hill cGPS
Main funding agency:
HBHS
June 2014
ETVZ
MRBL
HBHS
Marble Point cGPS
PGKH
VGET
PGNE
Hamilton Boys High School
strong-motion station
TRMS
July 2014
BOWS
TKHL
WHFS
TRMS
Whataroa Fire Station strong-motion
station
Tiraumea strong-motion station, a now
permanent site following the Eketahuna
earthquake response.
YALD
Yaldhurst cGPS
SEDS
Seddon Fire Station
strong-motion station
Oct 2014
Kahui Hut cGPS
12 – GEONET
HANM
MRBL
WHFS
YALD
ISSN 1176-0567 (Print) ISSN 1178-4201 (Online)
Sept 2014
PGKH
SEDS