DISCOVERDISCOVERDISCOVERDISCOVERdiscover UNDERSTANDUNDERSTANDUNDERSTANDUNDERSTAunderstand APPLYAPPLYAPPLYAPPLYAPPLYAPPLYapply ISSUE No.4 AUGUST 2013
globeMAGAZINE
including: sw eet win for honey industry Isotope science throws honey a lifeline Novel use for radiocarbon
Measuring CO2 emissions with radiocarbon Earthquakes and bulk water supply A wakeup call for Wellington’s water supplies globeMAGAZINE
CARBON calling Phapotogr hy: Radiocarbon dating is one of the most widely known scientific techniques. However, Lloyd Homer, Margaret Low, less well known is that New Zealand scientists were at the forefront of its development Heidi Roop, Julian Thomson, in the early 1950s. As a result of this trailblazing work, this year the New Zealand Tourism Bay of Plenty, radiocarbon community is celebrating the 60th anniversary of the publication of the The Dominion Post. first radiocarbon dates in 1953. Our Rafter Radiocarbon Laboratory, where it all began, is the oldest continually operating radiocarbon lab in the world. Design: Darren D’Cruz Dating with radiocarbon acts as a kind of egg-timer to measure the time that has elapsed since an organism died and stopped taking in carbon from its environment. Cover photo:. It works for objects that are up to 50,000 years old. Sixty years ago, the pioneer There are about 380,000 bee- developers knew they were on to something big, but they may not have realised that hives in New Zealand. Isotope radiocarbon would become a cornerstone scientific technique for dozens of industries science supports the bee and scientific disciplines. industry which, directly and indirectly, contributes about Applications include dating antiquities, atmospheric studies, archaeology, climate $5 billion annually to the research, oceanography, geology, earthquake, volcano, and tsunami research, marine New Zealand economy.
biology, and tracing the movement of carbon atoms through the environment for carbon Story pages 6 & 7 accounting. For example, radiocarbon has given us the dates of the more recent Taupo The information in this publication eruptions, and dates for the last 24 ruptures on the Alpine Fault in the South Island – may be copied and distributed to providing a remarkable 8000-year history of activity on this fault. others, provided GNS Science is acknowledged as the source of the In spite of the fact that there about 140 radiocarbon laboratories in the world, the Rafter information. Under no circumstances Laboratory, with its recently upgraded accelerator mass spectrometry facility, has may this information be changed carved out a special niche. This is because of its continual drive to improve precision, without the express permission of its commitment to prompt turn around times, and its willingness to take on new or GNS Science. challenging dating assignments. It has become a preferred facility for those who have special requirements such as high precision or small sample size – just a few milligrams ISSN 1179-7177 (Print) of carbon. Its precision is now routinely plus or minus 20 years. It has also expanded ISSN 1179-7185 (Online) its capabilities to measure beryllium-10 and aluminium-26, in addition to carbon-14. This versatility ensures it contributes to a wide range of science applications in GNS Science, Te Pū Ao, is the New Zealand. New Zealand science organisation that focuses on geological resources, More recently Rafter Radiocarbon staff have successfully trialled a new application – environmental and industrial isotopes, measuring industrial greenhouse gas emissions. We thank Vector who generously and geological hazards. By applying its allowed us access to their Kapuni facility for this project. Outlined on page 9, it shows scientific knowledge, GNS Science there is now an independent technique to verify self-reporting of greenhouse gas creates wealth, protects the emissions by industry. The project has strong parallels with one of the early applications environment, and improves the safety 2 of radiocarbon in New Zealand - the pioneering measurements of atmospheric carbon of people. dioxide at Baring Head near Wellington. This long record of measurements has, over many decades, been a vital contributor to global atmospheric studies and climate models. GNS Science employs 390 staff and has offices in Lower Hutt, Taupo, and John Callan Dunedin. Editor
Copyright © 2013.
issue 4 C ontents 4
4 gPS Survey Keeping track of land deformation
6 sweet victory for honey Isotope science throws honey a lifeline
8 Novel use for radiocarbon Measuring CO2 emissions with radiocarbon 10
10 fAst data for Bay of Plenty I nstant access to 3D geology and groundwater information
12 am tsun i study Mitigating tsunami risk in coastal development
14 p slo e failure S tudy promises to reduce the risk of building on slopes
16 lAKebed secrets 14 L ake Ohau sediment a key to understanding climate patterns
18 eARthquakes and bulk water supply A wakeup call for Wellington’s water supplies
20 the big ice melt 30,000 years of detailed Antarctic climate history revealed
22 a eDuc tion outreach S cience rocks at school geocamp 16 23 Puzzle Crossword
globe August 2013 urvey S
PS G
Kee piNG track of land deformation Each summer our geodesists set off for different parts of New Zealand with a battery of GPS receivers to get precise measurements of the way the land surface is deforming due to tectonic forces. Different parts of New Zealand are moving at different rates and in different directions. In some places this movement is increasing the stress in the earth’s crust, and in other places it is releasing stress.
Annual summer GPS campaigns boost During February 10 people, including Scientists generally survey one area the measurement capability of the staff from Land Information NZ, worked each year, so the entire country is GeoNet-operated permanent GPS in pairs to undertake an 18-day GPS re-surveyed every eight years. instrument network. The denser measurement campaign of 164 survey 4 instrument coverage provided by the marks in the lower North Island. This However, they carry out extra surveys in short-term campaigns delivers more was part of a long-term programme areas where elevated geological activity detailed information in the gaps of summer campaigns, for which is occurring or where deformation between the permanent stations for geodesists have portioned New Zealand assessment is particularly complex. For deformation and hazard modelling. into eight zones – four in the North example, there have been numerous Island and four in the South Island. surveys in the Canterbury region in the wake of the September 2010 and February 2011 earthquakes.
issue 4 Stewart Bennie (left) and Neville Palmer make a GPS measurement near Moonshine Road, north of Wellington. Each summer they make more than 100 GPS measurements in a different part of the country to determine how fast the surface of New Zealand is deforming due to tectonic forces.
Photo: Margaret Low
Repeated measurement over time Horizontal positions have an accuracy phenomena such as volcanism, enables scientists to keep a detailed of 3-4mm while vertical positions are geothermal activity and movement of track of the way our landscape is accurate to 6-9mm. They show that, in freshwater in aquifers. While geodesists deforming. Deformation rates are not general, much of the Wellington region are careful to filter out effects from smooth and it is common to detect is moving southwest at about 45mm-a- these phenomena, those data are fluctuating rates over a period of year relative to Australia. There are also useful to other scientists in related months or years. small changes in height as the region is research areas such as volcanology, gradually squashed horizontally by geothermal energy, and groundwater. The survey marks that contribute to this tectonic forces. long-term project range from well- Data acquired from short-term known trig stations to metal pins set in Each of the eight zones has its campaigns feeds into numerous concrete or rock outcrops in remote peculiarities and challenges. The Taupo aspects of earthquake science and locations. The GPS instruments are left Volcanic Zone, in the central North hazard modelling. on site for 48 hours of continuous data Island, is generally measured more recording and then shifted to a new frequently as the geological processes Contact: Neville Palmer, 5 survey mark to repeat the process. are occurring faster and there is more GNS Science, Lower Hutt Combining the accumulated data from variation than in other regions. There is ([email protected]) each site with specialist processing more active faulting, and the crust is techniques enables a very precise thinner and moving relatively fast. But location for each survey mark, specific this brings challenges to geodesists in to the date of the observation. the form of ‘unwanted signals’ from
globe August 2013 weet victory for honey Isotope science S throws honey a lifeline Isotope science and the honey industry have teamed up to find out why genuine New Zealand honey was failing an internationally accepted test that detects adulteration with cane sugar. The test failures represented a cloud hanging over the industry until GNS Science was able to show that the international test was inadvertently biased against some New Zealand honey varieties, especially our biggest export honey, Manuka.
The honey industry typically exports Prior to 2010, New Zealand honey Importing countries are slowly adopting product worth about $110 million products were not routinely tested on the new testing criteria. Prior to these annually with Manuka honey making up arrival in destination countries. However, changes, beekeepers were faced with the bulk of this. The scientist leading the overseas countries became more either holding on to their high-value project, Karyne Rogers, uncovered the vigilant with testing in 2010 in the wake Manuka honey, or blending it with other anomaly, and instigated an assessment of a sharp increase in honey fraud lower value honey to bring down its of testing procedures in government originating from Asia. Asian countries apparent cane sugar levels. The new testing laboratories in 10 countries, were selling inferior sugar-adulterated changes will free up about $40 million while refining the testing method in our honey, containing harmful residues and of export Manuka honey, which Stable Isotope Laboratory in Lower Hutt. antibiotics, into premium markets previously did not meet the standard world-wide. The increased testing was from the old criteria. Dr Rogers has successfully lobbied useful to detect issues with Asian honey, international authorities to change but it also found that New Zealand Allied to this project, Dr Rogers is the test criteria to accommodate Manuka honey was prone to fail the working with the industry to optimise New Zealand honey that was giving sugar isotope test. bee nutrition by assessing different bee false-positive test results. The test itself forage sources to minimise remains the same, but the interpretation Within a year, six shipments of supplementary sugar and protein of test results for Manuka honey has New Zealand honey worth about $6 feeding, so the bees stay healthy, are been changed. Its carbon isotope value million failed border tests and this more resistant to disease, and produce is now the main indicator of purity. threatened to close market access into consistently high quality honey. the United States and China. The To be acceptable to importing New Zealand honey was genuine, but Dr Rogers was recently recognised with countries, honey must have a cane its false-positive test results led the National Beekeepers’ Association sugar content below 7 percent. The overseas agencies to assume that appreciation award for significant flawed method was not measuring the sugar adulteration was the cause. contributions to the honey industry. To real cane sugar content, and gave only date her research has been funded by an ‘apparent’ value. The new criteria AGMARDT, the Ministry of Primary allow atypical honey, such as Manuka, Industries, and industry groups. 6 to have slightly higher apparent sugar levels as long as its carbon isotope Contact: Karyne Rogers, value is within a certain limit. GNS Science, Lower Hutt ([email protected]) Photo: Margaret Low
issue 4 Isotope scientist Karyne Rogers with her award from the National Beekeepers’ Association for significant contributions to the industry. Her work has helped to keep export markets open for Manuka honey.
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globe August 2013 Radiocarbon dating has long been seen as one of the most significant scientific developments of the 20th century. It can now be used to measure greenhouse emissions from industry. Novel use for radiocarbon
Ma e suring CO emissions 2 with radiocarbon
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issue 4 New Zealand scientists have achieved a world first by measuring the carbon dioxide output from a large industrial plant by radiocarbon dating its gas emissions. This novel application of radiocarbon dating shows there is now an independent technique to verify self-reporting of greenhouse emissions by the operators of large industrial plants.
In a trial at the Kapuni Natural Gas plant governments and industry of fossil fuel This technique is being trialled on a in Taranaki, the scientists led by Jocelyn usage. As emission targets become region-wide basis in the US and Europe, Turnbull and Liz Keller of our Rafter more common, the temptation to but this is believed to be the first time it Radiocarbon Laboratory, radiocarbon under-report will also grow. This has been successfully applied to an dated carbon dioxide in the atmosphere technique has the potential to keep individual ’point source’ site. The Kapuni downwind of the plant. They also everyone honest. plant is ideal for the trial for several radiocarbon dated grass from paddocks reasons. The operators have provided adjacent to the plant, as grass faithfully The project is a collaboration involving detailed information on their emissions records the radiocarbon content of the GNS Science and NIWA, and has the on an hourly basis; the plant is carbon dioxide that has been support of Vector - the owner of the surrounded by farmland, which photosynthesized from the atmosphere. Kapuni plant. At its heart is the isotope eliminates potential distortions from Both measurements showed good carbon-14, which is continually urban or industrial sources; lastly, the correlation with the known carbon produced in tiny amounts in the upper flat terrain and well documented dioxide emissions from the plant. atmosphere when cosmic rays hit weather data make it easy for scientists nitrogen atoms. The resultant carbon-14 to model gas dispersion rates. Natural gas from Kapuni consists of isotope gets into all living things and Measuring CO about 40 percent carbon dioxide that remains in equilibrium with the The first phase of the project involved 2 must be stripped off before the gas is environment while the organism is alive. collecting samples of grass at 10 sites suitable for domestic use. The stripped When the organism dies, carbon-14 around the plant and calculating the
carbon dioxide, along with water vapour, starts to decay at a known rate. fossil fuel CO2 concentration in emissions vents to the atmosphere through a parts-per-million contained in the air 35m-high flume at the plant. Generally all traces of carbon-14 have that the grass had photosynthesised. disappeared after 60,000 years. This provides a long-term average figure with The goal of the project is to use Because of their age, fossil fuels contain for carbon dioxide emissions. In the atmospheric measurements of no carbon-14. So carbon dioxide second phase, a helium weather balloon radiocarbon in carbon dioxide to produced from fossil fuels has no was used to collect downwind accurately quantify emissions of carbon-14 signature and can be readily atmospheric samples for analysis at radiocarbon fossil-fuel carbon dioxide. The distinguished from naturally produced numerous heights between 10m and technique, once perfected, could carbon dioxide, which has a 100m above the ground. In both cases, complement existing carbon accounting recognisable carbon-14 signature. With the carbon-14 measurements were methods that monitor how much carbon some clever maths, the ratio of among the most accurate ever achieved
dioxide regions and industries are carbon-14 measurements reveals CO2 at the Rafter Radiocarbon Laboratory. producing. More particularly, it could emissions in tonnes-per-day. help in verifying the self-reporting by Contact: Jocelyn Turnbull, GNS Science, Lower Hutt ([email protected])
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Trials conducted at the Kapuni Natural Gas plant in Taranaki have shown that radiocarbon dating is a viable method for verifying carbon dioxide output from industrial plants.
globe August 2013 lenty P ay of B ast data for F
In nsta t access to 3D geology and groundwater information W e have developed an interactive portal that provides instant access to information on groundwater systems and geology in three dimensions in the Bay of Plenty. Simply by entering a street address, map coordinates or a smart phone’s GPS, it is possible to instantly call up relevant information.
The initiative, believed to be the first of its developed was too large to serve over Called ‘Earth Beneath Our Feet’, the type in New Zealand, is the result of a the internet, so we developed a simpler model shows the main geological units partnership between Bay of Plenty package for internet use. down to bedrock plus a range of Regional Council and GNS Science, with information about groundwater in Bay both organisations funding the The product is part of a larger project in of Plenty. This includes depth at which 10 development of the product. The Council which our scientists are developing groundwater is most likely to be found. provides its groundwater information, three-dimensional subsurface Landowners and contractors can use such as borehole data and groundwater geological models of the Taupo this information to help with drilling consents, on a web site. GNS Science Volcanic Zone to better understand the decisions without having to initially supplements this with information on geometry, fluid flow pathways, and involve the Council. aquifer characteristics, also available to layer properties of the geological units the public. The product we initially in this part of New Zealand.
issue 4 Groundwater scientist Connie Tschritter uses her cellphone Senior Environmental Scientist at the to access geological and groundwater information Council, Janine Barber, says when the directly beneath her feet in the Bay of Plenty. product goes live, in December 2013, landowners, consultants and students will have information on geology and groundwater at their fingertips. She sees it as a win-win, with the public having ready access to the Council’s data and GNS Science models, while it frees up Council staff from responding to routine inquiries.
The information can be accessed by computer or by a smart phone app. The data served up on the smartphone app is a stripped-down version of the ‘Earth Beneath Our Feet’ website. Features of the app include access to geological model profiles below a point on the ground surface identified via a cell phone’s GPS, map coordinates or a street address.
These 3D subsurface models can also be used to assess geothermal resources. In particular, they can be used to identify the large-scale water flow ‘cells’ associated with geothermal fields.
Contact: Paul White, GNS Science, Wairakei ([email protected])
Below: A vertically exaggerated and simplified 3D model of the geology of Bay of Plenty and the location of the main faults. Information from this model will be available via a smartphone app later this year through the Earth Beneath Our Feet project. Photo: Margaret Low
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globe August 2013 12
Tsunami study d in t coastal areas in New Zealand. forother ablueprint to become expected is has been incorporated into issue 4 of southeast spreads development urban as strip, coastal a10km-wide in people to 40,000 up P of southeast coast the along development commissioned in plans for study urban in regions first ofthe one is enty in area the have incorporated a GN planning. longterm into its y of New Zealand to incorporate hazards tsunami B M ap a amoa. su e P i c l t T v h T ere are plans to accommodate iga a uranga. uranga. nam o e l a T h op e way this hazard hazard e way this T t st C h o e local councils e local councils uncil plans uncil plans ing i S a r
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Peru, with 16 hours travel time. time. travel 16 with hours Peru, of coast the off originating to atsunami impact, of warning hour’s an than less with Plenty of Bay the in faults offshore from ranged Sources each. for damage building and life of loss distance, period, wave height, inundation return the estimated and scenarios likelihood of 12 potential tsunami the on reported We areas. greenfield to developed highly from range – which Te and Tumu Wairakei, – Papamoa, ‘suburbs’ coastal three was focus The mitigation in measures their plans. include could they so environment built the and life human on impact resulting the model and events tsunami of potential inundation the on to report us Council Regional Plenty commissioned of Bay groups. community and industry with working Council Regional Plenty of Bay and Council, District Plenty of Bay Western Council, City Tauranga involving –acollaboration SmartGrowth of banner the under goes growth The plan for managing this population t Rapid urban development along the Bay of Plenty coast has prompted local authorities to incorporate the risk of tsunami in their planning.
Photo: Bay of Plenty Tourism
Maximum worst-case water depths Our report suggested a number of In Te Tumu, the farthest suburb from above mean sea level (wave heights) measures that can be incorporated into Tauranga, we recommended the ranged from 3m for a local tsunami to land use planning to reduce loss of life. provision of multi-level facilities to 14m for a rupture of the Hikurangi They include: provide vertical evacuation. These subduction zone about 400km northeast refuges should be 30 percent (plus 3m) • Retaining the existing sand of Papamoa. Return periods range from higher than the maximum credible dunes as they can be an 50 years for a tsunami originating in tsunami inundation depth and have important natural barrier to a South America to 800 years for a provision to accommodate people for tsunami. tsunami originating from a fault under 24 hours. the seafloor in the Bay of Plenty. • Designing future development to recognise the tsunami risk Contact: James Beban, Using a risk-based approach, the and include mitigation measures GNS Science, Lower Hutt Council proposed acceptable, tolerable in the design of coastal ([email protected]) and intolerable thresholds for deaths developments to reduce the from a tsunami. Several of the larger impacts of a tsunami eg, vertical scenarios resulted in intolerable levels evacuation structures. of risk. These larger events arrived on • Formulating a detailed shore 50 minutes after fault rupture, evacuation plan for the meaning people in these areas would coastal area and ensuring that not receive an official warning before routes are clearly marked and the tsunami arrived. 13 communicated to the public. Routes should lead to multiple safe areas where there is shelter, water, toilet facilities, and cooking equipment.
globe August 2013 14
Slope failure issue 4 prompted the evacuation of a number of anumber evacuation the prompted of houses. To help reduce the hazard hazard the To reduce help of houses. from urban landslides, GNS Science GNS Science landslides, urban from is undertaking a project to quantify quantify to aproject undertaking is suburb of Kingston in June 2013 June in of Kingston suburb landslides on the hill suburbs of suburbs hill the on landslides This landslide in the Wellington Wellington the in landslide This the risk of earthquake-induced of earthquake-induced risk the Christchurch and Wellington. Wellington. and Christchurch
Photo: The Dominion Post Photo: The Dominion Post e high cost of remedying unstable urban slopes in in slopes urban unstable ofremedying cost e high T The ultimate result will be a ‘slope code’ code’ a‘slope be will result ultimate The will focus mostly on slopes higher than 10m and greater than 30 30 than greater 10m and than higher slopes on mostly focus will r r udy pro S o three-year project, being led by engineering geologist earthquake shaking. during performance expected angle, height, of based slope of classes engineering considerations on certain magnitudes. different of earthquakes the of models computer dimensional geologists will develop two- material, geological our engineering turn. it’s Wellington’s now and amplification ofisenergy shaking The highest ground-shaking. amplify they way the in land to flat differ Slopes ones. small –even earthquakes during shake slope the of parts different classes of slope based on likely response to earthquake shaking. shaking. to earthquake likely response on based ofslope classes slopes in Wellington and Christchurch Christchurch and Wellington in slopes slopes. Deploying the instruments in a a in instruments the Deploying slopes. seismometers across characteristic underlying geological material, and it making slope, the of top the at usually Christchurch for the past two years, years, two past the for Christchurch and and degrees in angle. inangle. degrees One of the first phases will be to install install be to will phases first the of One earthquake-induced landslides in those two cities. cities. two those in landslides earthquake-induced is to produce a map of hill suburbs in both cities showing different different showing cities both in suburbs ofhill amap to produce is Based on this data, and the underlying underlying the and data, this on Based that will provide guidance for for guidance provide will that to ‘synthetic’ respond they how to see Shakingdata the mostpart. vulnerable severely how show will slope, the temporary arrays of sensitive sensitive of arrays temporary long line from the top to the bottom of of bottom to the top the from line long has been collected on the Port Hills in in Hills Port the on collected been has h W t i e n e llington has given rise to a project to quantify the risk of of risk the to quantify to aproject rise given has llington s d s k of bu of k uc m lop i “We will be able to compare the the to compare able be will “We The benefits of the project will be be will project the of benefits The why will quantify investigations The our up tightening in greatly help will This considered. One of the project’s project’s the of One considered. that be should measures engineering and Wellington in slopes different the during Hills Port the on computer modelling results with the engineering approach. approach. engineering will give guidelines on the type of of type the on guidelines give will specificengineering treatmentsand it Wellington and Christchurch need understanding of the way these slopes slopes way these the of understanding up to six classes of slope, with each each with slope, of classes to six up of development the be will milestones Christchurch behave in certain ways. ways. certain in behave Christchurch Christchurch aftershock sequence. Dr Massey says. Massey Dr two-fold: it will of which identify parts large volume of data we have collected collected we have data of volume large behave during earthquakes,” having its own recommended s e
e t e s to to s s h i e ld This work is expected to help the the to help expected is work This get site-specificengineering advice. the says Massey Dr development. are increasingly using a science- ofdecision-making councils, which engineering requirements for other less for other less requirements engineering to progressively be could option councils and engineers to produce a a to produce engineers and councils will work with geologists engineering dealing with development on slopes. withdraw housing from the most most the from housing withdraw particularly steep should slopes, stillparticularly People bullet. amagic not is project vulnerable classes. classes. vulnerable and slopes vulnerable to stipulate makers to decide the next step. One One step. next the to decide makers Contact: Contact: It will be up to planners and policy- and to planners up be will It Based on our findings, GNS Science Science GNS findings, our on Based technical guidance document for intending to build on slopes, based approach to dealing with urban urban with to dealing approach based
T h C e long-term aim aim e long-term GN ([email protected]) C C h h ristchurch ristchurch h ris Massey, S
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15 akebed secrets L
Lake Ohau sediment a key to understanding climate patterns It is a measure of New Zealand’s importance in efforts to understand Southern Hemisphere climate patterns, that scientists are treating sediment from a high country lake like gold.
In a project that involves collaborators The project will produce one of the An improved understanding of Southern from five countries, researchers are most detailed long-term terrestrial Hemisphere climate dynamics is methodically collecting and analysing records of South Island climate to date. fundamental to international research sediment cores from the bottom of It will be used to investigate the efforts that aim to determine how the Lake Ohau to build a record of annual relationship between large-scale global climate system works. The vast climate in the central South Island atmospheric and oceanic climate expanse of ocean in the southern 16 extending about 1500 years back in features driven from Antarctica and the mid-latitudes and limited landmass time. The ultimate goal is to recover a tropics, and New Zealand’s climate. highlights the value of records from 100 metre-long core from beneath the Lake Ohau is ideally located to capture New Zealand. Remarkably, major storm lake bed to reconstruct climate for the the response of South Island rainfall to events and even earthquakes can be past 17,000 years - Earth’s most recent changes in Southern Hemisphere faithfully recorded in Lake Ohau’s period of global warming. westerly wind circulation. sediment layers. Scientists use a range of analytical techniques to interpret these signals.
issue 4 The Hopkins River draining into the head of Lake Ohau, in the South Island, provides high sediment input during large rainstorms. This relationship is crucial for reconstructing the lake’s climate history.
Photo: Heidi Roop The Lake Ohau project has several properties of the sediments such as Using precise time markers at annual components. Collection of modern grain size, layer thickness, and density. intervals, they will be able to assess hydrological data is crucial and relies Changes in grain size can reflect climate and environmental change on a range of high-tech instruments variability in the amount of water through each annual package of deployed in the lake to record physical entering Lake Ohau, which changes in sediment for the past 1500 years. characteristics including water current response to large rain storms or flow, water clarity, and temperature. increased snow accumulation in winter. Contact: Marcus Vandergoes, Scientists also collect climatological Scientists will also investigate pollen GNS Science, Lower Hutt data from a network of automated and diatom populations in the ([email protected]) weather stations and purpose-built sediment. The species and abundance traps that collect sediment flowing into of diatoms can be used to indicate lake the lake from the Dobson and Hopkins productivity and temperature through Rivers. The amount of sediment entering time, as certain species thrive at 17 the lake reflects rainfall in the catchment. different temperatures. The species of pollen is a direct indication of on-land As well as characterising the modern conditions. They will also measure hydrological and sedimentary systems isotopes including caesium-137, and of the lake, scientists will analyse lead-210, and use radiocarbon dating to sediment cores using physical date the sediment layers.
globe August 2013 Earthquakes and bulk water supply
A wakeup call for Wellington’s water supplies T he loss of bulk water supplies as a result of a large earthquake in Wellington could be a bigger problem than some suspect. Recent modelling by GNS Science has produced figures showing the scale 18 of the challenge and how various mitigation measures could improve the lot of Wellingtonians in a post-quake environment. One of the main purposes of the modelling was to estimate the quantities of water that might be needed from sources other than stored water, until restoration of the bulk supply system.
issue 4 Seismic strengthening of the Stuart Macaskill water storage 160,000 lakes at Te Marua, north of Current Wellington, is underway as part 140,000 of an upgrade to the capital’s Whakatikei Dam 120,000 bulk water supply system. Even Whakatikei & Steel with the upgrades completed, 100,000 Wellington could still face significant water shortages in 80,000 the event of a large earthquake. 60,000
40,000 People Without Water Without People 20,000
0 0 10 20 30 40 50 60 70 80 Days from Earthquake
This graphic shows the biggest reduction in time to restore bulk water to Wellingtonians after a quake comes from a combination of a new dam and replacing old fragile underground pipes.
The findings draw on results from the Our scientists modelled two ways of multi-year It’s Our Fault and the reducing water deficit times. This Crown-funded Post-Earthquake suggests that building a new dam west Functioning of Cities projects which of the Wellington Fault could reduce aim to make Wellington more resilient restoration times by about two weeks, through improved understanding of and replacing old fragile pipes with earthquakes in the region and their robust steel and plastic pipes could impacts on humans and the built reduce restoration times to reservoirs environment. Our investigation by a similar amount. While neither considered nine quake scenarios, with measure on its own was able to most of the focus on a magnitude 7.5 eliminate the water supply gap, quake on the portion of the Wellington combining both measures could do so Fault that extends through the city. for all but the largest of earthquakes.
Key findings are that bulk supply lines Authorities are using the findings to would suffer multiple breaks and prioritise upgrading measures for the become inoperative. With distribution capital’s bulk water supply. Greater pipes also out of service, queues of Wellington Regional Council (which Wellingtonians would form at most of provides bulk water) is part-way A wakeup call the city’s 44 reservoirs to collect their through an extensive upgrading daily supply of water. Reservoir water programme that includes rapid would last between two and six weeks, bypassing of the bulk supply main depending on the rate of consumption. where it is expected to be ruptured by for Wellington’s Bulk water would be restored fault movement, and evaluating new progressively, taking about three weeks sources of water. Capacity (the to reach Tawa (the suburb closest to company that manages the water water supplies the source) and up to 10 weeks to distribution network) is progressively reach Miramar (the most distant suburb upgrading its pipelines as part of its from the source). asset replacement programme.
The problem that arises is that in many Property owners who take the trouble places there will be a sizeable gap to collect and store rainwater from their between depletion of stored water, and roofs would be in a much stronger 19 restoration of bulk supply to the position compared to those without any reservoirs. At worst, in Miramar, there stored water. could be about 15,000 people without access to either stored or mains water Contact: Jim Cousins, for up to 40 days. Suburbs further north, GNS Science, Lower Hutt and closer to Kaitoke, have shorter ([email protected]) restoration times.
globe August 2013 Victoria University PhD candidate Peter Neff was one of a large team of scientists processing and analysing ice core from the Ross Ice Shelf at our Ice Core Research Centre in Lower Hutt. Here he uses a special band saw to cut the 1m-lengths of core
he big ice melt into longitudinal slices prior to analysis. This operation takes T place in a refrigerated room at minus 20 degrees Celsius.
30,000 years of detailed Antarctic climate history revealed T his winter an international group of scientists melted and analysed 760m of ice core from the Ross Ice Shelf to in a bid to reveal 30,000 20 years of Antarctic climate history. Working with military precision in our ice core research facility in Lower Hutt, they melted an average of 20m of core a day to produce a detailed climate record from the edge of the frozen continent.
issue 4 The ice core was collected by a drilling Melting of the ice cores in the Part of the meltwater is immediately operation at Roosevelt Island in laboratory represents the intermediate siphoned off into a network of fine Antarctica over the past two summers. stage in the nine-nation Roosevelt plastic tubes and taken to eight At the drill site, scientists cut the core Island Climate Evolution project. It will different analyses stations. into 760 one-metre lengths and sent it be followed by many months of Measurements are so precise, to Wellington in refrigerated containers. analysis and interpretation. The scientists will be able to say exactly The island is on the edge of the Ross precision melting involves two teams what winter and summer conditions Ice Shelf – a crucial location because it of scientists working back-to-back 12 were like in coastal Antarctica 20,000 is where the ocean, atmosphere, and hour shifts. First, using special band years ago. Some measurements are in the ice sheet meet. Physical, chemical saws, they cut the metre-long cores parts per quadrillion. The first analyses and biological changes are well lengthwise into seven thin slices. The include airborne carbon particles, dust recorded in the Roosevelt Island ice. outside slices are slid into plastic bags particles, stable isotopes, and the and put back in the freezer and stored concentration of methane trapped in at minus 35 degrees Celsius. Some tiny gas bubbles. The carbon particles, are kept for archiving and others for for instance, show when large forest later analysis. fires occurred in Australia and when coal-burning became widespread. The centre slice, considered the most Large volcanic eruptions are also pure, is placed vertically in a continuous recorded, and provide a useful time melting apparatus where it rests on a marker. Also deduced from the 10cm-diameter nickel hot plate kept at a meltwater are atmospheric and constant 36 degrees Celsius. It melts at sea-surface temperatures, and the a rate of 3cm-a-minute or about extent of the Ross Ice Shelf, which has 20m-a-day. retreated by 1000km during the past 30,000 years. The surface cores are melted first and then the scientists slowly work their The rest of the meltwater is collected in way down the core – or back in time. At tens of thousands of small plastic the top, there are about four years of bottles, or vials, and immediately weather recorded in every metre of frozen. Some vials are destined for core. Weight and compression means overseas collaborators who will the deepest ice contains dozens of measure a range of parameters annual weather cycles. including trace elements, heavy metals, and rare earth elements. The rest remain in New Zealand for future analysis. More than 25 different types of analyses will be performed on the meltwater by the end of this year.
One of the key findings from this New Zealand-led project will be figures showing how quickly the Ross Ice Shelf, about the size of France, retreats because of warming temperatures in the ocean and in the atmosphere. This will help increase the accuracy of global climate models. Initial results from the analyses are expected this year.
Contact: Nancy Bertler, GNS Science, Lower Hutt ([email protected])
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Photo - Margaret Low
globe August 2013 Education outreach Science rocks at school geocamp
Students on the two-week Geocamp explore the lower slopes of Mt Taranaki. This was one of six field trip destinations where the students studied rocks, fossils, and landforms to reveal the geological evolution of the Taranaki province.
Photo - Julian Thomson H ands-on earth science was the focus for students and teachers from five Taranaki schools who took part in a recent two-week course at Puke Ariki Museum in New Plymouth.
Called ‘Power of the Planet Geocamp’, After making careful observations Taranaki was chosen for this year’s the GNS Science-led course attracted during each field trip, the students Geocamp because of its varied and 24 intermediate-aged students and a spend time sharing their observations interesting geological history. The number of teachers. It followed a similar and interpreting them through province’s economy also depends on event in Napier in 2012. The aim of questioning, discussion and hands-on science-based industries such as oil these geoscience immersion courses is modelling to arrive at understandings and gas production and dairying. to introduce students to the excitement of the geological phenomena. of scientific inquiry and discovery. The Geocamp has been made possible Then they were challenged to by support from The Todd Foundation, Course facilitator Julian Thomson, of communicate their new knowledge Puke Ariki Museum, and the Royal GNS Science, says the best way to through posters, 3D models, videos, Society of New Zealand. teach geoscience is by doing it - going and experiments at a one-day public into the field to study landscapes and science expo of their own creation. Held These two short videos give a flavour rock outcrops and working out the at Puke Ariki Museum, the expo allowed of the Geocamp. The first shows the geological processes they reveal, using them to become the communicators students making observations at some authentic scientific processes. and educators, which reinforced their of Taranaki’s spectacular geological self-confidence in science. sites: http://youtu.be/UyUBqY7DlZY The course involved a mix of fieldwork and hands-on learning sessions at “We try to empower the students. To The second shows the students in Puke Ariki. Fieldwork destinations make them realise that you don’t have action with their science expo at Puke 22 included several sites along the wild to be a professional scientist to discover Ariki Museum. Taranaki coast as well as the ski-field and do science,” Mr Thomson says. http://youtu.be/pCpApWwF0NY on Mt Egmont-Taranaki to study rocks, fossils, and landforms. The teachers also benefit from the Contact: Julian Thomson, professional development which they GNS Science, Lower Hutt take back and share at their schools to ([email protected]) add enduring value to the Geocamp.
issue 4 P uzzle
Crossword
DOWN clues are “straight” clues, basically definitions. 1 2 3 4 5 6 7 8
ACROSS clues are in cryptic form, where only part of the clue 9 is a definition (appearing, not always obviously, at the clue’s 10 11 beginning or end). The other part hints at the answer by means of wordplay, though sometimes it is just another definition. 12 13
Crossword compiled by Brent Southgate 14 15 16 17 For Crossword solutions, click on www.gns.cri.nz/globe 18 19
20 21 22 23
24
25 26 27 28
29 30
Across (cryptic) 31 32 1 Prison camp fragment found in limestone cave (10) 6 Displacement vector of undergarment (4) Down (straight) 10 Toaster wrecking the planet does this daily (7) 1 Intensity of force acting on a body as a function of its 11 Grieved to see medical officer and editor holding area (6) container for ashes (7) 2 Device for sending or receiving radio-frequency 12 Paid job with little or no work that includes velocity waves (7) or waveform of simple periodic oscillations (4,5) 3 Arch-shaped fold in rocks (9) 13 Least possible measure of field strength (5) 4 Device that emits microwave radiation (5) 14 Element obtainable from Umbria (6) 5 Characteristically mild in climate (9) 16 Current device, ATM, mere rubbish (7) 7 Satellite coverage designed to 19 Skill with quartz fragment (3) scan vegetation cover (7) 20 Notice deuterium is with particle physics lab (7) 8 Branch of medicine concerned with feet (8) 22 A long-range weather forecast circulated on line (2,4) 9 Sharp increase in wind strength (4) 25 Two sides separated by (exclamation of 15 Pressure gauge (9) enlightenment!) a catastrophic mudflow (5) 17 Codename of atomic bomb project (9) 27 Indicate a position that’s said to yield white iron 18 Hero-worshipped (8) pyrite (9) 21 Swedish discoverer of tungsten – a tungsten ore was 29 Always sit around in the radiation dose unit (7) named for him (7) 23 30 Crystal arrangement strangely tactile (7) 23 More loud (7) 31 Legal document might just as well be read 24 Treatment for an illness (6) backwards (4) 26 Submerged ridge of rock (4) 32 Helmholz potential sadly not supplied by power companies (4,6) 28 Small valley on the moon (5)
globe August 2013 Coming up…
what: NZ Institute of Physics Conference When: 27–30 September 2013 Where: Rutherford Hotel, Nelson WEB: www.nzip.org.nz
What: NZ Hydrological Society & Meteorological Society Joint Conference When: 19–22 November 2013 Where: Palmerston North Convention Centre Web: www.nzhsmetsoc.org.nz
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