geonet news - Latest News
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geonet news - Latest News
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: s.page@gns.cri.nz 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: b.scott@gns.cri.nz 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: b.scott@gns.cri.nz 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: s.cox@gns.cri.nz 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: s.cox@gns.cri.nz 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: landslides@gns.cri.nz 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: s.ashraf@gns.cri.nz 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: d.whitelaw@gns.cri.nz 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 d.barton@gns.cri.nz CONNECT... /geonetnz @geonet @geonet_above4 @geonet_above5 geonet-shakennotstirred.blogspot.co.nz/ geonet-scienceinaction.blogspot.co.nz/ geonet-dev.blogspot.co.nz/ Email: s.mcbride@gns.cri.nz 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: info@geonet.org.nz 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: l.dixon@gns.cri.nz 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