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General circulation models (GCMs) and their downscaled regional‐scale equivalents have been important tools for climate‐change studies. However, there has been limited assessment of the performance of GCMs and downscaled models in simulating extreme storms in temperate coastal environments. This study assesses the model characterization of extreme storms on the heavily populated coast of south‐east Australia. Twenty‐year average recurrence interval (ARI) storm intensities derived from generalized extreme value (GEV) distributions based on observed and large‐scale atmospheric model data are compared. Changes in extreme storms from past climate to a high‐emission future scenario are also investigated. Simulations of storm minimum surface pressures compared favourably with measured data. Both the GCMs and downscaled models reproduced the observed decrease with increasing latitude along the coast in the 20 year ARI of minimum surface pressure. Both indicated that the minimum storm surface pressure should change negligibly in a high‐emission future. Although the models underestimated the maximum daily precipitation significantly, models are improving significantly with CMIP epoch and downscaling. In the high‐emission future scenario, the GCMs and NARCliM projected the 20 year ARI maximum daily precipitation would increase in the order of 25%. GCMs and the corresponding downscaled products presently do not represent the extreme value distributions of historical wind speed data well, overestimating at smaller values of ARI and significantly underestimating in larger values of ARI. Significant changes in the magnitude of the 20 year ARI maximum daily‐average onshore wind speed are not projected for the high‐emission future. [ABSTRACT FROM AUTHOR]

In recent years, various forms of group work have been introduced in university courses across various subject domains, including construction management courses. Although the use of group work in higher education has sound pedagogical reasons and advantages, group work has its own drawbacks. Therefore, the acceptance by students and the success of group work critically depend on a fair and credible assessment of the group process. In this paper, the implementation of different approaches to peer assessment (PA) of individuals' contributions to group projects in two core units in an undergraduate construction management course in an Australian university is reported. The effectiveness of the adopted PA approaches have been evaluated and validated by students. It has been found that contrary to doubts of the sufficiency of a simplistic approach to PAs, the fairness of a PA approach does not necessarily depend on its complexity. Besides, voluntary group discussions, learning and collaboration are found to aid in improving each of the group's camaraderie. Hence, it is recommended that academics should develop both a structured methodology to progressively encourage group members to work cohesively in teams and effective PA approaches that measure individual member's contribution. (Contains 2 tables.)

Achieving coastal and shallow-water bathymetry is essential for understanding the marine environment and for coastal management. Bathymetric data in shallow sea areas can currently be obtained using SDB (satellite-derived bathymetry) with multispectral satellites based on depth inversion models. In situ bathymetric data are crucial for validating empirical models but are currently limited in remote and unapproachable areas. In this paper, instead of using the measured water depth data, ICESat-2 (Ice, Cloud, and Land Elevation Satellite-2) ATL03 bathymetric points at different acquisition dates and multispectral imagery from Sentinel-2/GeoEye-1 were used to train and evaluate water depth inversion empirical models in two study regions: Shanhu Island in the South China Sea, and Heron Island in the Great Barrier Reef (GBR) in Australia. However, different sediment types also influenced the SDB results. Therefore, three types of sediments (sand, reef, and coral/algae) were analyzed for Heron Island, and four types of sediments (sand, reef, rubble and coral/algae) were analyzed for Shanhu Island. The results show that accuracy generally improved when sediment classification information was considered in both study areas. For Heron Island, the sand sediments showed the best performance in both models compared to the other sediments, with mean R2 and RMSE values of 0.90 and 1.52 m, respectively, representing a 5.6% improvement of the latter metric. For Shanhu Island, the rubble sediments showed the best accuracy in both models, and the average R2 and RMSE values were 0.97 and 0.65 m, respectively, indicating an RMSE improvement of 15.5%. Finally, bathymetric maps were generated in two regions based on the sediment classification results. [ABSTRACT FROM AUTHOR]

Forecasting transport and fates of marine debris spilled from lost ship containers is increasingly important. This paper builds a forecast framework by forcing a state-of-the-art particle-tracking model with operational oceanic and atmospheric forecasts, and compares simulations with the spotted debris from an actual maritime container spill in the south-eastern Australia water. In coastal areas, patterns of the spotted debris can be approximately simulated when applying surface current forecasts of an eddy-resolving resolution, along with the horizontal dispersion, Stokes drift and windage. The strengths and shortcomings of various forecast datasets varied. Therefore, a thorough analysis of various forcing datasets might be required when performing a marine debris forecast. The horizontal dispersion coefficient can be used to parameterize the unresolved small-scale processes. Stokes drift and windage, especially the latter one, can be important for the debris movements. This study suggests that some global forecast models can be used with certain confidence to forecast debris movement, however, not all are equivalent and cautions are warranted. [ABSTRACT FROM AUTHOR]

This study quantifies some of the potential impacts of climate change and nutrient pollution to identify the most important factors on water quality changes and algal blooms in the study region. Three variables, air temperature and streamflow, representing climate change, and nutrient runoff, were varied in eight hypothetical scenarios to determine their impact on water quality and algal blooms by the calibrated and validated water quality model QUAL2K. Water quality was assessed by the concentrations of dissolved oxygen, total nitrogen, and phosphorus. Algal blooms were identified by phytoplankton concentration. An increase in air temperature of up to 2 °C resulted in an average increase of 3% in water temperature and 4.79% in phytoplankton concentration, and an average decrease of 0.48% in dissolved-oxygen concentration. Projected decreases in streamflow not only made the above phenomenon more significant but also significantly increased the concentration of total nitrogen, total phosphorus, and phytoplankton with the same pollution inputs. Under climate change, the biggest cause of concern for estuarine water quality is reduced streamflow due to decreases in rainfall. Water quality improvement is possible by regulating the concentration of non-point-source pollution discharge. By reducing nutrient runoff, the total nitrogen and phosphorus concentrations were also reduced, resulting in a significant increase in the dissolved oxygen concentration. This study highlights the most significant factors for managing water quality in estuaries subject to climate change. [ABSTRACT FROM AUTHOR]

Coastal upwelling is important for marine ecosystems and the economy, because of its elevated primary and secondary productivity and large potential for fish catch. This study developed a scale-independent and semi-automatic image processing technique to map the upwelling areas along the 4500 km south-eastern coast of Australia from 14-year monthly MODIS Sea Surface Temperature (SST) data. The results show that there is significant spatial variability in the mapped upwelling areas, month to month, season to season and year to year. There is also strong temporal (month to month, seasonal and inter-annual) variability of the upwelling characteristics in area of influence, SST anomaly, chlorophyll-a concentrations and upwelling speed. This study identifies two prominent upwelling systems, the NSW system along the coast of New South Wales and the WVIC/SA system along the coast of western Victoria and adjacent South Australia. The NSW coastal upwelling system occurs more or less continuously from austral spring to autumn. The WVIC/SA coastal upwelling system is a seasonal upwelling system occurring in the austral summer. The NSW coastal upwelling system has a stronger upwelling intensity than the WVIC/SA system, in terms of area of influence, SST anomaly, chlorophyll- a concentrations and upwelling speed. We believe that the NSW coastal upwelling system, especially the northern and central parts, is mainly driven by the East Australian Current (EAC) and its eddies; while, the WVIC/SA coastal upwelling is a typical wind-driven system. In addition, the results indicate that the El Nino Southern Oscillation (ENSO) events are likely to have a low-to-moderate impact on both the NSW and the WVIC/SA coastal upwelling systems. The El Nino (La Nina) events tend to strengthen (weaken) upwelling intensity. • A scale-independent and semi-automatic upwelling mapping technique is developed. • There is strong temporal variability of the upwelling characteristics. • Two persistent upwelling systems off south-eastern Australian coast are identified. • ENSO events are likely to have a low-to-moderate impact on both upwelling systems. [ABSTRACT FROM AUTHOR]

Globally the rapidly developing coastal zone is the focus of public interest and particularly since the 1970s many countries have advocated and adopted public participation as a key process in coastal development applications. This is acknowledgement of public interest in the decision-making regarding coastal developments. Taking Australia and China as examples, this research compares the practical performance and existing problems of public participation in regard to specific coastal development applications. Two marinas on the most rapidly developing coastal zones of these two countries were selected as study cases. A diversity of coastal stakeholders, including government officials, academics, businessmen, non-government organization staff and local residents, were interviewed in order to capture their detailed opinions on public participation. This comparative research analyzes the major findings and discusses reasons for public participation, approaches and timing of public participation and existing problems of public participation in coastal development applications. The similarities and differences between Australia and China may inspire researchers and managers to have more effective public participation in future coastal developments. [ABSTRACT FROM AUTHOR]

Purpose – The purpose of this paper is to investigate and uncover key determinants that could explain partners' commitment to risk management in public-private partnership projects so that partners' risk management commitment is taken into the consideration of optimal risk allocation strategies. Design/methodology/approach – Based on an extensive literature review and an examination of the purchasing power parity (PPP) market, an industry-wide questionnaire survey was conducted to collect the data for a confirmatory factor analysis. Necessary statistical tests are conducted to ensure the validity of the analysis results. Findings – The factor analysis results show that the procedure of confirmatory factor analysis is statistically appropriate and satisfactory. As a result, partners' organizational commitment to risk management in public-private partnerships can now be determined by a set of components, namely general attitude to a risk, perceived one's own ability to manage a risk, and the perceived reward for bearing a risk. Practical implications – It is recommended, based on the empirical results shown in this paper, that, in addition to partners' risk management capability, decision-makers, both from public and private sectors, should also seriously consider partners' risk management commitment. Both factors influence the formation of optimal risk allocation strategies, either by their individual or interacting effects. Future research may therefore explore how to form optimal risk allocation strategies by integrating organizational capability and commitment, the determinants and measurement of which have been established in this study. Originality/value – This paper makes an original contribution to the general body of knowledge on risk allocation in large-scale infrastructure projects in Australia adopting the procurement method of public-private partnership. In particular, this paper has innovatively established a measurement model of organisational commitment to risk management, which is crucial to determining optimal risk allocation strategies and in turn achieving project success. The score coefficients of all obtained components can be used to construct components by linear combination so that commitment to risk management can be measured. Previous research has barely focused on this topic. [ABSTRACT FROM AUTHOR]

The author discusses the information of the Integrated Marine Observing System (IMOS) and its significance to commercial fishing in Australia. The author mentions IMOS's benefits to the country's commercial fisheries including fishery management improvement and fishing efficiency and safety enhancement. The author also denotes the IMOS's probability and statistical methods.

Despite the great benefits that it can potentially contribute to modern workplace environment, raised floor system (RFS) encountered many barriers in the process of its applications for the fitout of office buildings in the Australian construction industry. Through a set of comprehensive research activities, the significant influence factors (SIFs) and problems associated with the RFS fitout implementation are identified. Further discussion of these SIFs and problems unearths a range of project level critical factors (PLCFs) pertaining to the RFS fitout design, construction, operation and maintenance, which presents firsthand checklists for the project team to review in the project delivery process. These factors need to be accommodated appropriately in order to enhance the implementation of the RFS fitout in Australian office buildings. Following a constructability study, a framework was developed by integrating these SIFs and PLCFs into the delivery of the RFS fitout in an aim to enhance the project constructability and minimize problems in the RFS service performance. [ABSTRACT FROM AUTHOR]

Risk allocation in privately financed public infrastructure projects, which are mainly referred to as public-private partnership (PPP) projects, is a challenging job due to the nature of incomplete contracting. An investigation into the mechanism that guides the formation of efficient risk allocation strategies is thus desirable. Drawing on the transaction cost economics and resource-based view of organizational capability, this paper has identified five main features of the transactions associated with risk allocation in PPP projects. They include partners’ risk management routine, partners’ risk management mechanism, partners’ cooperation history, risk management environmental uncertainty, and partners’ risk management commitment. For achieving cost efficiency, different risk allocation strategies may suit different conditions of the features. Accordingly, a theoretical framework and five hypotheses were proposed for testing. Data collected in an industrywide survey were analyzed using multiple linear regression technique. It was found that generally, the identified features are determinants in the decision-making process of efficient risk allocation. Therefore, the proposed theoretical framework provides both government and private agencies with not only a logical and holistic understanding of but also a support tool for decision making on risk allocation strategy in PPP projects. Study limitations and future research directions are also set out. [ABSTRACT FROM AUTHOR]

Darwin Harbour is a flood-dominated estuary with a large tidal range. Tides are considered to be the dominant factor influencing sediment resuspension and transport in the harbour during the dry season. However, the sediment dynamics during the wet or monsoon season have been little explored using either field data or numerical hydrodynamic modelling. This study focused on understanding the sediment dynamics during the monsoon and the dominant factors controlling the suspended-sediment concentration (SSC) in Darwin Harbour. Using the Finite Volume Coastal Ocean Model (FVCOM) coupled with the Simulating Waves Nearshore (SWAN) model, we investigated the effect of waves on the SSC during a particular wet season. SSC distributions modelled with tidal currents and wave in the outer harbour were significantly different to those only with tidal currents. Due to the narrow harbour entrance, strong monsoonal waves in the outer harbour barely propagated into the inner harbour; the SSC in the inner harbour was therefore almost hardly affected by waves. Numerical results show that the criterion of neglecting wave forcing in a macro-tidal environment when the tidal range is larger than 3 m is inaccurate, and that the effects of waves on the SSC can still be important in waters with a large tidal range such as Darwin Harbour. • The wave-current coupled sediment dynamics model was, for the first time, developed to investigate the wave effects on sediment transport in Darwin Harbour, during monsoon period. • Sediment flux was landward at the entrance of Darwin Harbour, but there was negligible landward sediment flux in the inner harbour. • Unlike Mehta (1988), the wave effects on sediment dynamics can not be neglected in the macro-tidal environment. [ABSTRACT FROM AUTHOR]

Turbidity is an indicator of the quality of water and usually exhibits variability associated with changing hydrodynamic conditions, which can be reflected in the sediment dynamics in coastal regions. Darwin Harbour is a typical macro-tidal, well mixed, and complex environment influenced by industries, human activities, and natural factors—including winds, currents, river discharges, waves, and tides. As a case study, hydrodynamics and sediment dynamics in Darwin Harbour are investigated using moderate resolution imaging spectroradiometer (MODIS) measurements. This study focuses on understanding the variability of turbidity, mechanisms that control the variations of turbidity and analyzing field data to determine the main factors that influence the sediment dynamics in Darwin Harbour. The results of this study illustrate the seasonal turbidity variation is mainly influenced by the wind waves. The dredging campaigns in 2013 and 2014 wet seasons contributed to the rise of turbidity in Darwin Harbour. The action of tidal currents appears to be the dominant factor controlling the turbidity pattern in a spring–neap cycle and the turbidity intra-tidal variation. In addition, the turbidity maximum zone (TMZ) near Charles Point is formed by the tidal current convergence based on the results of current modelling. [ABSTRACT FROM AUTHOR]

Three well-known Australian beaches, Surfers Paradise Beach (Gold Coast), Narrowneck Beach (Gold Coast) and Bondi Beach (Sydney), were selected for analysis of beach user preferences for certain weather and ocean conditions. Regression methods were used to determine how the numbers of visitors to these beaches are affected by these conditions. Actual visitor numbers were counted at three times during the day over several months at each beach with the aid of web cameras. The corresponding weather and ocean conditions were obtained from the Australian Bureau of Meteorology and local government agencies. Weekly and seasonal factors were also considered. The conditions preferred by beach users, as found in this study, are: no precipitation, higher temperatures, light-to-moderate wind speed (less than 30 km/h) and low wave height (up to 1.25 m). This study, the first to provide an analysis of beach user preferences for both weather and ocean conditions, shows that ocean conditions play a significant role in explaining the demand for beach recreation in Australia. It is therefore necessary for tourism management authorities or local governments to provide accurate and timely weather and ocean information to local, domestic and international beach users.