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We know that extremes in ocean temperature often extend below the surface, and when these extremes occur in shelf seas they can significantly impact ecosystems and fisheries. However, a key knowledge gap exists around the accuracy of model estimates of the ocean's subsurface structure, particularly in continental shelf regions with complex circulation dynamics. It is well known that subsurface observations are crucial for the correct representation of the ocean's subsurface structure in reanalyses and forecasts. While Argo floats sample the deep waters, subsurface observations of shelf seas are typically very sparse in time and space. A recent initiative to instrument fishing vessels and their equipment with temperature sensors has resulted in a step-change in the availability of in situ data in New Zealand's shelf seas. In this study we use Observing System Simulation Experiments to quantify the impact of the recently implemented novel observing platform on the representation of temperature and ocean heat content around New Zealand. Using a Regional Ocean Modelling System configuration of the region with 4-Dimensional Variational Data Assimilation, we perform a series of data assimilating experiments to demonstrate the influence of subsurface temperature observations at two different densities and of different data assimilation configurations. The experiment period covers the 3 months during the onset of the 2017-2018 Tasman Sea Marine Heatwave. We show that assimilation of subsurface temperature observations in concert with surface observations results in improvements of 44% and 38% for bottom temperature and heat content in shelf regions (water depths< 400m), compared to improvements of 20% and 28% for surface-only observations. The improvement in ocean heat content estimates is sensitive to the choices of prior observation and background error covariances, highlighting the importance of the careful development of the assimilation system to optimize the way in which the observations inform the numerical model estimates. [ABSTRACT FROM AUTHOR]

This paper presents on-going challenges in the present paradigm shift of earthquake-induced ground motion prediction from empirical to physics-based simulation methods. The 2010–2011 Canterbury and 2016 Kaikoura, New Zealand earthquakes are used to illustrate the predictive potential of the different methods. On-going efforts in simulation validation and theoretical developments are then presented, as well as the demands associated with the need for explicit consideration of modelling uncertainties. Finally, discussion is also given to the tools and databases needed for the efficient utilisation of simulated ground motions both in specific engineering projects as well as for near-real-time impact assessment. • ?On-going challenges in physics-based ground motion prediction and insights from the 2010–2011 Canterbury and 2016 Kaikoura, New Zealand earthquakes? by BA Bradley. • Illustration of the predictive performance of physics-based simulations of the 2010–2011 Canterbury and 2016 Kaikoura, New Zealand earthquakes as compared with empirical prediction alternatives. • Discussion of the on-going challenged in physics-based ground motion simulation methods. [ABSTRACT FROM AUTHOR]

• Flexural behaviour of press-braked S960 UHSS channel section beams were studied. • 20 beam tests were performed about the minor axes in the u and n orientations. • Numerical simulations and parametric studies were conducted. • The applicability of the design codes was assessed based on test and FE results. A thorough experimental and numerical study of the flexural behaviour and strengths of press-braked S960 ultra-high strength steel (UHSS) channel section beams bent about the minor principal axes is reported in this paper. The experimental study was conducted on eight different UHSS plain channel sections, and included measurements on the material flat and corner properties and initial local geometric imperfections of the beam specimens as well as 20 four-point bending tests performed about the minor principal axes in both the 'u' and 'n' orientations. A complementary numerical investigation was then conducted, where finite element (FE) models were firstly developed and validated against the experimental results, followed by parametric studies carried out to acquire further numerical data over a broader range of cross-section dimensions. It is worth noting that the existing design codes for steel structures, as established in Europe, America and Australia/New Zealand, are only applicable to those with material grades up to S690 (or S700 for Eurocode) and cannot be directly used for S960 UHSS structural members. In the present study, the applicability of the codified design provisions and formulations for flexural members to the examined S960 UHSS channel section beams was evaluated, based on the ultimate moments derived from structural testing and numerical modelling. The quantitative evaluation results generally revealed that the current European code provides overall consistent and precise flexural strength predictions for Class 1 and Class 2 S960 UHSS channel sections in minor-axis bending, but leads to a high level of inaccuracy (scatter and conservatism) for the design of their Class 3 and Class 4 counterparts, whilst the American specification and Australian/New Zealand standard result in scattered and excessively underestimated design flexural strengths, except for the cases of slender S960 UHSS channel section beams in 'u'-orientation bending. [ABSTRACT FROM AUTHOR]

This paper describes the process and results of validating a simulation model of agriculture for a region in New Zealand. Validation is treated as a process, in which simulation models are made useful for specific purposes by making them conform to observed historical trends and relationships. In this case, the model was calibrated to reproduce the year-by-year conversion to dairying from 1993 to 2012 in Southland, New Zealand. This was achieved by holding constant some elements of the simulation model, based on economic theory or data, and by running simulations on a range of values for two key parameters. The paper describes the model and process, and demonstrates that empirical validation is possible if approached pragmatically with a view to the intended use of the model. Important elements are: using stylised facts to limit the parameter space ex ante, establishing the range of model outcomes and focusing on the most likely parameter space, focusing the search for parameter values where there is the greatest uncertainty, and using historical data to calibrate models. [ABSTRACT FROM AUTHOR]

On 26 November 2011, an indicative referendum was held in New Zealand with the aim of gauging public support for a change from the current parliamentary electoral system (mixed member proportional) to one of four alternatives. To understand the consequences (in terms of the seat distribution of parties in Parliament) of a change in electoral system, we created an online simulator several months before the referendum date. Several interesting research issues arose in this work, which in our opinion deserve greater analysis. We describe the assumptions made in order to create such a simulator, and their consequences. [ABSTRACT FROM PUBLISHER]