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Holocene marine terraces occur globally and record information about the timing and magnitude of past coseismic events. Staircased terraces develop through repetitive coseismic uplift of shore platforms, but are also subject to destruction from subsequent wave erosion and rock weathering. In this study we calibrate a rock coast evolution model using terrace field data from Mahia Peninsula, New Zealand, and use it to investigate how relative sea level (RSL) change influences Holocene terrace development. Analyses of 10,002 simulations reveal time periods of extremely rapid terrace creation and destruction as a result of shore platform development processes that are modulated both by episodic and gradual RSL change scenarios. Subtle differences in these scenarios give rise to completely different terrace sequences, even if coseismic event timing is held constant. Improved interpretation of Holocene terrace sequences require higher resolution paleo RSL data and chronological data on shore platform development. Plain Language Summary: Holocene marine terraces develop when tectonically active rock coasts are uplifted during earthquakes, and thus provide the information about the timing and magnitude of past seismic events that is useful to estimate future seismic hazards. However, the record is often partial because once terraces are uplifted, subsequent marine erosion processes (wave erosion and intertidal rock weathering) start destroying terraces and can completely remove them from the landscape. This can confound paleo‐seismic interpretations of Holocene terrace sequences. In this study we used a numerical model to explore how earthquake‐driven episodic and climate‐driven gradual relative sea level (RSL) changes can influence marine erosion processes, and therefore Holocene terrace preservation. The simulation results reveal that subtle differences in episodic and gradual RSL change histories can lead to periods in which marine erosion are greatly accelerated, which can completely alter terrace sequences that are preserved in the landscape. Until this study, we had little understanding of the way in which RSL modulates the erosion processes that control terrace creation and destruction. We conclude that better interpretation of past seismic event history from Holocene terraces require a more detailed understanding of RSL history and higher resolution data on rates of shore platform formation through time. Key Points: The effects of episodic and gradual relative sea level (RSL) change on Holocene marine terrace development are numerically exploredEven subtle differences in RSL have large impacts on shore platform development rates, thereby changing preserved terrace sequencesBetter understanding of past RSL and shore platform development history will improve paleo‐seismic interpretation of Holocene terraces [ABSTRACT FROM AUTHOR]

Introduction: The aim of this work is to report diagnostic reference levels (DRLs) for hybrid positron emission tomography and x-ray computed tomography (PET/CT) exams in Australia (AU) for Queensland (QLD) and Western Australia (WA) (AU QLD/WA) and New Zealand (NZ).Methods: Two-structured booklets were designed to collect dose information, patient demographics, equipment details and acquisition protocols for fluoride-18 fluorodeoxyglucose (18 F-FDG) PET/CT procedures, and any additional diagnostic CT routinely performed as part of 18 F-FDG whole-body examination. The DRL was reported based on the 75th percentile and achievable dose for 18 F-FDG, CT dose index volume (CTDIvol ) and dose length product (DLP). The effective dose and total effective dose was reported for 18 F-FDG whole-body PET/CT examination. Also, the effective dose was reported separately for identified additional diagnostic CT.Results: The findings of this study show that the current DRL for 18 F-FDG in AU QLD/WA and NZ was 333.75 MBq and 332.87 MBq, respectively. The reported AU QLD/WA CTDIvol and DLP associated with 18 F-FDG whole-body PET/CT examinations from vertex to thigh (VT) was 4.41 mGy and 474 mGy.cm. In NZ, the reported VT CTDIvol and DLP was 13.07 mGy and 1319.05 mGy.cm. The effective dose for 18 F-FDG and CT component was 5.6 mSv and 4.7 mSv for AU QLD/WA. For NZ, the effective dose was 5.7 mSv and 10.9 mSv for 18 F-FDG and CT component. The total effective dose delivered from the 18 F-FDG whole-body scan from the AU QLD/WA PET/CT centres (10.44 mSv) were lower than the radiation doses delivered from the NZ (16.65 mSv).Conclusions: The current DRLs were proposed for AU QLD/WA and NZ for 18 F-FDG whole-body PET/CT examinations. Variations existed in the current practice of AU QLD/WA and NZ PET/CT examinations. There is a need to optimize the radiation doses delivered from PET/CT examinations. [ABSTRACT FROM AUTHOR]

ABSTRACT Kench, P.S.; Ryan, E.J.; Owen, S.; Bell, R.; Lawrence, J.; Glavovic, B.; Blackett, P.; Becker, J.; Schneider, P.; Allis, M.; Dickson, M., and Rennie, H.G. 2018. Co-creating resilience solutions to coastal hazards through an interdisciplinary research project in New Zealand, In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 1496–1500. Coconut Creek (Florida), ISSN 0749-0208. Coastal communities ‘living at the edge’ face intensification and acceleration of coastal hazard risk in the face of climate change. Communities will need to be adaptive in reducing these risks now and over long timeframes. Developing coastal hazard adaptation pathways requires co-production of interdisciplinary knowledge between scientists, policy makers and communities. However, there remains little guidance and limited dialogue about the research practices and frameworks that underpin co-created research. In a first for New Zealand, a co-created research programme is underway titled ‘Living at the Edge’ that aims to improve the resilience of coastal communities to coastal hazards. This paper provides novel insights into the complexities underpinning the formative stages of co-created research, drawing on practical experience from the Living at the Edge project. We explore the enablers and shapers that led to co-created shifts in the research project objectives and framework. Notions of integration, trust, and flexibility are three fundamental aspects that influenced the early stages of co-creation. The importance of bridging interactions with actors early on in co-created projects is exemplified. [ABSTRACT FROM AUTHOR]

Most field studies of wave processes on shore platforms in front of eroding cliffs focus on a single site, revealing aspects of wave dynamics at that location. Here, we analyse data from six platforms around northeastern New Zealand and describe the fundamental control of shore platform width, gradient and elevation on wave processes, including greater attenuation of short-period waves at lower tidal stages and increases in longer period wave energy towards the cliff toe. These data suggest that empirical formulae developed from coral-reef environments provide better predictions of wave height on platforms than formulae currently used in shore platform models. [ABSTRACT FROM AUTHOR]

ABSTRACT Few studies of wave processes on shore platforms have addressed the hydrodynamic thresholds that control wave transformation and energy dissipation, especially under storm conditions. We present results of a field experiment conducted during a storm on a sub-horizontal shore platform on the east coast of Auckland, New Zealand. Small (<0.5 m) locally generated waves typically occur at the field site, whereas during the experiment the offshore wave height reached 2.3 m. Our results illustrate the important control that platform morphology has on wave characteristics. At the seaward edge of the platform a scarp abruptly descends beneath low tide level. Wave height immediately seaward of the platform was controlled by the incident conditions, but near the cliff toe wave height on the platform was independent of incident conditions. Results show that a depth threshold at the seaward platform edge > 2.5 times the gravity wave height (0.05-0.33 Hz) is necessary for waves to propagate onto the platform without breaking. On the platform surface the wave height is a direct function of water depth, with limiting maximum wave height to water depth ratios of 0.55 and 0.78 at the centre of the platform and cliff toe, respectively. A relative 'platform edge submergence' (water depth/water height ratio) threshold of 1.1 is identified, below which infragravity (<0.05 Hz) wave energy dominates the platform energy spectra, and above which gravity waves are dominant. Infragravity wave height transformation across the platform is governed by the relative platform edge submergence. Finally, the paper describes the first observations of wave setup on a shore platform. During the peak of the storm, wave setup on the platform at low tide (0.21 m) is consistent with measurements from planar sandy beaches, but at higher tidal stages the ratio between incident wave height and maximum setup was lower than expected. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Waves are an important process responsible for the initiation and subsequent development of intertidal shore platforms. However, few field studies to date have described wave processes on shore platforms. A field experiment was conducted using an across-shore array of wave gauges, including a directional sensor, on a near-horizontal platform at Mahia Peninsula, North Island, New Zealand. Results show that the platform is very efficient in filtering wave energy at gravity wave frequencies (>0.05 Hz), with 40-80% reduction in wave height measured across the 140 m wide platform. By contrast, infragravity waves are present on the platform and increase in magnitude towards the cliff toe. Directional wave analysis indicates that wave reflection is mainly restricted to infragravity wave frequencies, demonstrating the differences in gravity and infragravity wave behaviour on the platform studied. Results indicate that, under fair weather conditions, the role of waves as an agent of cliff toe erosion is likely to be limited at present, although they are probably important for removing sediments accumulated at the cliff toe. The observed increase in infragravity wave energy towards the cliff toe implies that these long-period waves may be important geomorphic agents on shore platforms. [ABSTRACT FROM AUTHOR]

ABSTRACT Infragravity wave (IGW) transformation was quantified from field measurements on two shore platforms on New Zealand's east coast, making this the first study to describe the presence, characteristics and behaviour of IGWs on rock platform coasts. Data was collected using a cross-shore array of pressure transducers during a 22 hour experiment on Oraka shore platform and a 36 hour experiment at Rothesay Bay shore platform. A low pass Fourier filter was used to remove gravity wave frequency oscillations, allowing separate analysis of IGWs and the full wave spectrum. Offshore IGW heights were measured to be 7 cm (Oraka) and 9 cm (Rothesay Bay), which were 21% (Oraka) and 7.5% (Rothesay Bay) the height of incident wave height. At the cliff toe, significant IGW height averaged 15 cm at Oraka and 13 cm at Rothesay Bay. This increase in IGW height over the platform during both experiments is attributed to shoaling of 40 to 55% over the last 50-60 m before the cliff toe, respectively. Shoaling across the platform was quantified as the change in IGW height from the platform edge to cliff toe, resulting in a maximum increase of 1·88 and 2·63 on Rothesay Bay and Oraka platforms. IGW height at the cliff toe showed a strong correlation with incident wave height. The proportional increase in IGW height shows a strong correlation to water level on each platform. The rate of shoaling of long period waves on the shallow, horizontal platforms increased at higher water levels resulting in a super elevation in water level at the cliff toe during high tide. Greater IGW shoaling was also observed on the wider (Oraka) shore platform. Results from this study show the first measurements of IGWs on shore platforms and identify long wave motion a significant process in a morphodynamic understanding of rock coast. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: Few large-scale field measurements of longshore sediment transport have been undertaken on beaches composed of coarse sediments, in part owing to difficulties associated with measurement in energetic swash zones in which large clasts are moving. Here we present results from a field experiment in which Passive Integrated Transponder tags were used to investigate patterns of cobble transport over 8months on a mixed sand and gravel beach on the east coast of New Zealand. The study objectives were to document rates of alongshore transport, and measure rates of cobble abrasion under field conditions. Cobble recovery rates were highly variable over the study period with 30–60% recovery at site 1 compared to much lower (0–20%) recovery rates at sites 2 and 3. Consistent uni-directional patterns of net alongshore sediment transport were observed. The median cobble transport rate was approximately 500m over 207days, indicating long-term net northward transport rates on the order of 2–2.5m/day. Results highlight a number of factors, in addition to longshore energy flux, that are important for understanding the observed patterns. In particular, across-shore sediment transport during storms may have been smaller at site 1 than the other sites owing to lesser wave exposure. This is partly responsible for higher cobble recovery rates at this site and also an increased amount of time during which cobbles were able to be transported alongshore on the lower beachface. Unique to this study, results demonstrate the use of PIT tags to provide direct measurement of cobble abrasion under natural processes. Repeat weight measurement on individually tracked cobbles show that after 207days the median loss was 11.3g, or 1.8% of total weight. There was a general trend of abrasion increasing with net transport distance, but longshore cobble movement was highly variable ranging from 130 to 2500m. [Copyright &y& Elsevier]

The article offers information on the study that focuses on the geomorphic change of an ebb-tidal delta at Mair Bank, Whangarei Harbor, New Zealand. It outlines the methods of the study including the assessment of planform change, bathymetric change, and Mair Bank volume estimates. The article also presents the conclusion drawn from the study.

University research in coastal geomorphology, processes and management has made a major contribution to the fundamental understanding of coastal systems in New Zealand over the past 43 years. This article examines the growth in university-based coastal research since 1964 and discusses the geographical pattern and themes of this research. Data indicate a significant geographical concentration of research effort and focus on a narrow range of research themes. Underlying reasons for these characteristics of New Zealand coastal research are explored and challenges facing university based research are discussed. Such challenges can be overcome through a more coordinated research effort to realize the huge potential to undertake coastal science of national relevance and international significance. [ABSTRACT FROM AUTHOR]

Coastal research and monitoring on New Zealand beaches have typically examined seasonal and event-driven (storms) changes in the coast. However, historical records are now of sufficient length to indicate that change occurs at longer timescales. This paper presents examples of multi-decadal change at three case-study locations around New Zealand. Results show that morphological adjustment of the coast occurs at multi-decadal scales and is much larger than short-term dynamics. Physical mechanisms driving changes are ill defined but may be associated with El Niños and La Niña episodes which modulate waves and sea level, as well as changes in sediment supply. [ABSTRACT FROM AUTHOR]

Abstract: Detailed measurements of cross-shore wave energy transformation, swash sediment transport and beach profile change under low energy conditions are reported from a mixed sand and gravel beach at Torere Bay, Bay of Plenty, New Zealand. Measurements were undertaken during a 10-day period following a storm event and document post-storm recovery of the beach. Nearshore wave spectra identify periods in which incident wave energy is dominated by swell and wind wave energy. Results show that wind wave energy observed in the nearshore is effectively removed from beachface spectra at the break-point step under lower tidal stages. Swash is driven by longer period swell energy although dissipation of short period wave energy is critical in entraining sediments on the lower beach. At higher tidal stages wind wave energy is able to propagate across the break-point step, shoal and break on the lower beachface. Tidal modulation of wave processes across the lower beachface under low incident wave conditions is found to stimulate active sediment reworking, migration of the break-point step and shoreward sediment flux to promote beach accretion. [Copyright &y& Elsevier]

Abstract This paper investigates the response of a mixed sand and gravel (MSG) barrier coastline to storms and sudden relative sea-level change using the numerical model XBeach-G. The barrier beaches of southern Hawke's Bay, New Zealand provide a natural laboratory for the work owing to spatial variability in instantaneous land deformation that occurred during the 1931 Hawke's Bay earthquake. Historic (1931) and contemporary (2017) morphodynamics of one tectonically uplifted (+1.5 m) and one subsided (−0.78 m) barrier were modelled under energetic waves (H s 1–6 m). XBeach-G was designed to simulate pure gravel beach morphodynamics, but despite this, the model demonstrated high quantitative skill when calibrated for the MSG coast. Results reveal the storm impact regimes of each profile and potential linkages to decadal-scale barrier development observed in historical beach profile data. Storm-swash processes at the uplifted profile indicate long-term barrier stability due to a lack of change at the barrier crest, and ridge building observed in model simulations provides a potential formative mechanism for decadal-scale beach progradation. At the subsided barrier, modelled historic crest build-up (up to 0.3 m) and narrowing (over 5 m) indicate an overtopping mode of response to sudden relative sea-level rise. Simulation results are consistent with historical beach profile observations that also show chronic narrowing of the subsided barrier through time. Simulations of the modern barrier draw attention to the possibility that it may be on a trajectory toward catastrophic breakdown under extreme conditions, but further work is needed to distinguish the relative importance of historical sudden sea-level rise versus deficits in sediment supply to this shoreline. Highlights • XBeach-G used to simulate storm, sea-level response of mixed sand/gravel barriers • Results analysed from sites exposed to earthquake-driven relative sea-level change • Chronic barrier narrowing potentially linked to sudden relative sea-level rise • Barrier with subsidence history may now be exposed to catastrophic breakdown. [ABSTRACT FROM AUTHOR]

Abstract: Waves are generally considered to be an important control on shore platform evolution but there have been very few detailed studies of wave dynamics on rocky coasts. This study provides a detailed description of wave transformation processes across a shore platform near Gisborne, New Zealand. A field experiment was conducted on an intertidal, 250m-wide platform that is characterised by a sharp seaward edge. Mean platform elevation is 0.7m below mean sea-level (MSL) and platform gradient is 0.3°. Four nearly equally spaced pressure gauges were deployed over a 24-h period during fair-weather swell conditions characterised by a mean wave height of 0.4–0.5m and wave period of 7s. Wave energy at the seaward edge of the platform was dominated by incident swell waves with peak frequency at 0.09Hz. At all tidal stages waves broke at the seaward edge of the platform, but changing tidal stage exerted a strong control on the rate of wave energy attenuation across the platform. The relative importance of waves at wind-wave frequencies increased in the centre of the platform as the tidal stage and water level increased, whereas infragravity waves became dominant toward the cliff toe. Three different hydrodynamic zones were distinguished across the shore platform; (i) a breaker zone close to the seaward edge; (ii) a propagation/shoaling zone in the central region of the platform; and (iii) a zone of energy dissipation across the inner part of the platform. The spatial dimensions of the three zones varied with changing tidal stage, enabling different wave processes to operate across different parts of the platform at different times. The experiment showed that wave-height attenuation is strongly controlled by tidal stage, ranging between 93% attenuation of wave height during the initial flooding stage to 44% attenuation at high tide. Wave height was found to be depth-limited, with the ratios of H max and H m0 to water depth calculated as 0.7 and 0.4, respectively. The findings imply that platform geometry has an important influence on wave processes on shore platforms. The geomorphic implications of gravity and infragravity waves are discussed. [Copyright &y& Elsevier]

Optimal nutrition care is important in the management of cystic fibrosis (CF). This paper summarises the '2017 Nutrition Guidelines for Cystic Fibrosis in Australia and New Zealand (NZ)'. CF dietitians formulated 68 practice questions which were used to guide a systematic literature search and review of the evidence for nutrition in CF. Identified papers underwent quality and evidence assessment using the American Dietetic Association quality criteria checklist and the National Health and Medical Research Council of Australia (NHMRC) rankings. Evidence statements, graded recommendations and practice points were developed covering core nutrition topics (assessment and nutrition interventions including oral, enteral and micronutrient supplementation); nutrition-related co-morbidities (including pancreatic insufficiency, CF-related diabetes, bone health and distal intestinal obstruction syndrome); and key new topic areas (genetic modulator therapies, overweight/obesity and complementary therapies). This paper showcases highlights from the guidelines, focussing on new topic areas and geographic and climate considerations for vitamin D, salt and hydration. • This paper summarises the 2017 Nutrition guidelines for CF for Australia and NZ • A systematic approach to evidence appraisal and guideline development was used • Nutrition assessment, nutrition support and micronutrient supplementation are covered • Nutrition-related topics including CF-related co-morbidities and PERT are covered • Novel topic areas include genetic modulators, overweight/obesity and probiotics [ABSTRACT FROM AUTHOR]