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• Nationwide streamflow projections for Australia informed by CMIP5 and CMIP6. • Vast majority of CMIP5 and CMIP6 GCMs project less winter rainfall across Australia. • Lower winter rainfall translates to a significant reduction in annual runoff. • Modelled median projection of runoff shows a 50% reduction in far southwest Australia. • Modelled median projection of runoff shows a 20% reduction in far southeast Australia. Projections of streamflow under future climate are essential for developing adaptation strategies in the water and related sectors. This paper presents nationwide streamflow projections for Australia informed by climate change signals in CMIP6 GCMs and compares the projections with those from CMIP5 GCMs. The modelled future runoff projections driven by CMIP5 and CMIP6 GCMs are relatively similar for far southern Australia. The median projection is a 50% reduction in mean annual runoff in far southwest Australia and 20% reduction in far southeast Australia by 2046–2075 relative to 1976–2015 under the high SSP5-8.5/RCP8.5 global warming scenario. The vast majority of CMIP5 and CMIP6 GCMs project less winter rainfall across Australia. As most of the runoff in far southern Australia occurs in winter and spring, the lower winter rainfall translates to a significant reduction in annual runoff. It is therefore prudent to plan and manage for a reduction in future water resources, particularly in the densely populated and important agricultural regions in southeast Australia. There is less agreement between GCMs in the summer rainfall projection, with the CMIP6 GCMs generally projecting a wetter future (or smaller decrease in rainfall) than the CMIP5 GCMs. The modelled median projection for mean annual runoff is a 10% reduction in the south-east coast, 5% reduction in the north-east coast and little change in northern Australia. More GCMs project an increase rather than a decrease in the interannual variability of rainfall, and this would further amplify multi-year hydrological droughts. [ABSTRACT FROM AUTHOR]

Fifth-generation district heating and cooling (5GDHC) systems have the potential to provide simultaneous heating and cooling, allowing for energy exchange between users with different needs. However, their viability in mild climates with a higher share of cooling demand remains unclear. In this paper, we propose a framework for assessing the engineering, economic and environmental performance of a 5GDHC system compared to a state-of-the-art business-as-usual solution and demonstrate it through a practical case study for a university campus in Melbourne, Australia. When accessible heat sources and sinks are available, the 5GDHC system provides a cost-effective solution, with annual cost savings between 9 and 29 % and GHG emissions reduction between 25 and 58 % compared to an already advanced business-as-usual system. Additionally, by using peak off-peak tariffs and an hourly emission factor for the electricity consumed, we demonstrate the 5GDHC operational flexibility in pursuing different objectives, such as minimising cost or emissions, respectively. The results suggest that 5GDHC systems are an economically and environmentally viable solution in milder climates, and a successful implementation of 5GDHC in Australia can create new market opportunities and pave the way for its adoption in other countries with similar climatic conditions and no established history of district heating systems. • 5GDHC systems are analysed in a new context with a milder climate. • A multi-dimensional assessment framework is proposed. • The framework is demonstrated through a practical case study in Melbourne, Australia. • Flexibility is assessed through varying electricity tariffs and emission factors. • The strong performance of the 5GDHC system offers insights into similar contexts. [ABSTRACT FROM AUTHOR]

Australians are one of the world’s highest per capita emitters of greenhouse gases, yet the country’s target for emissions reductions by 2030 remains modest. This paper looks at policy options for Australian cities to deliver faster emissions reductions than the national commitment level. The main focus is on an accelerated reduction in emissions from urban road transport, through technological improvements and behaviour changes. Targets are proposed for improved emissions intensities, to bring Australia much closer to US and EU performance expectations. A range of behaviour change measures is then tested on Melbourne and Sydney, the Sydney analysis using MetroScan-TI, an integrated evaluation framework, to explore how behaviour changes might enhance emissions outcomes. The potential contribution of public transport is a particular focus. The paper concludes that, with sufficient political will, Australia could reduce its 2030 road transport emissions to 40% below 2005 levels. This is a much larger reduction than the current 26–28% Australian target but is more consistent with longer term pathways to acceptable carbon budgets. [ABSTRACT FROM AUTHOR]

Coastal aquifers provide a source of water for more than one billion people, with island freshwater lenses being some of the most vulnerable coastal groundwater systems due to their susceptibility to saltwater intrusion. Basic hydrogeological and hydrochemical knowledge regarding the recharge and salinisation processes of freshwater lenses is important to ensure sustainable utilisation, especially considering possible climate change effects. This paper makes an assessment of the fate of a freshwater lens in a drying climate through a comparison of current and historic hydrochemical data, which to the author’s knowledge is unique to this study. Fresh groundwater stable isotope signatures (δ 18 O, δ 2 H) reflect local amount weighted rainfall signatures (δ 18 O: −3.8‰; δ 2 H: −15.1‰), and confirm rainfall as the origin of fresh groundwater (δ 18 O: −4.47 to −3.82‰; δ 2 H: −20.0 to −16.6‰). Mixing with seawater was identified through enriched groundwater δ 18 O and δ 2 H signatures (maximum values of −0.36‰ and −1.4‰ respectively) compared to local rainfall and higher salinity (maximum 29,267 mg/L Total Dissolved Solids (TDS)) in a number of monitoring wells around the freshwater lens. Enhanced seawater intrusion detected in the northern section of the lens area was identified through significantly increased TDS values over the last 20–40 years, with increases of up to 3000% observed between 1990 and 2014. A reduction in the extent of freshwater by approximately 1 km 2 was identified since 1977, which was found to be primarily caused by a reduction in recharge to the freshwater lens due to a ∼20% decline in winter rainfall in the south-west Western Australian region since the mid 1960s. Groundwater abstraction was found to equate to between 5% and 9% of the estimated recharge for the island, and is not a significant factor in the reduction of the lens extent compared to the observed decline in rainfall recharge. Interestingly, seawater intrusion into the fresh water lens was found to occur by older seawater (0.03–0.09 TU) in regions of the lens that were previously fresh or slightly brackish, while one sample (0.67 TU) suggests either modern seawater intrusion or mixing of older saline groundwaters (>60 years) with rainfall recharge. The use of tritium dating in this island aquifer was essential in identifying ‘older’ seawater that was previously unidentified until now. The isotopic and hydrochemical tools used in this paper quantify the effects of groundwater abstraction and climate variability on the freshwater lens and have implications for the sustainable management of the groundwater resource on Rottnest Island, and elsewhere. [ABSTRACT FROM AUTHOR]

Since its first use in the late 80's, the term chevron has been employed in numerous studies to describe large U- and V-shaped ridges found in or near shorelines worldwide. Most studies have so far focused on Bahamian chevrons that are exclusively of Late Pleistocene age, and on the supposed Holocene chevrons found in S-Madagascar and Australia. In the Bahamas, these deposits have been interpreted as the product of extreme storms at the end of the last interglacial (LIG) warm period. In contrast, the extensive chevrons complex exposed in S-Madagascar and on the western coast of Australia have been associated with a tsunami induced by a meteorite impact. Finally, several authors have also proposed a non-catastrophic (i.e. eolian) origin based on the recognized importance of wind-related processes in these coastal areas, and term such deposits parabolic dunes. In this paper, we collect and synthesize existing data on the morphology, sedimentology and age of these chevrons, and review the different interpretations proposed in the literature with the aim to lay out a consistent database to assist further investigations on these important coastal morphologies. In addition, we generated a synthesis of wind data at the three study areas, which highlights the relationship between present wind regimes and chevrons morphologies. The ubiquity of chevrons (likely actually parabolic dunes) in coastal areas around the globe and their relationship with coastal processes makes them crucial archives for reconstructing past wind regimes. [ABSTRACT FROM AUTHOR]

The paper describes a risk analysis of the economic impact of damage to metal roofing of a typical contemporary (new) Australian house subject to extreme wind loading. The failure modes considered are roof cladding and batten-to-truss connection failures, with the effect of defective construction also considered. Monte-Carlo simulation and structural reliability methods are used to stochastically model spatially varying pressure coefficients, roof component failure, and load re-distribution across the roof. This spatial reliability analysis enables fragility curves to be developed that relate likelihood and extent of roof cover loss to gust wind speed. The annual economic risk is up to 0.3% of house replacement value. A typical house with construction defects increases economic risk more than sixfold when compared to the defect-free house. There is a 10% chance that a changing climate will increase expected losses for houses in Brisbane and Melbourne by 6–18% over the next 50 years. [ABSTRACT FROM AUTHOR]

A key criterion of successful adaptation to climate change is that it avoids potential inequalities arising from climate impacts or from adaptation strategies themselves. Recent research on adaptation in developing and developed countries argues that the measures of such fairness cannot be captured by standard metrics of vulnerability and should be situated in the milieu of people’s daily lives and temporalities. Yet there is little empirical evidence to support this theoretical argument. This paper describes a method, and presents findings from research that aimed to understand and classify the lived values of four marginal rural communities at risk of sea-level rise in Australia to inform adaptation planning and implementation. Our research finds that there are at least five types of primary residents and second home-owners attached to these four low-lying coastal communities. Some of these residents are more likely to be amenable to relocation if their needs for affordable living and belonging are met. For others, there may be little that can be done to compensate for the loss of place attachment, and implementing a measured approach that provides them time to adapt to the idea of change and form connections to new places is the best that could be achieved. We discuss the implications of place-specific and people-centric values for achieving fair adaptation. [ABSTRACT FROM AUTHOR]

Global climatic change is driving research and development in low emissions technologies. One such technology is the use of charcoal from biomass in steelmaking. This paper adapts social life cycle assessment methodologies to analyse the social dimensions of energy supply alternatives in steelmaking using regionalised production scenarios in Australia. Three energy supply alternatives are investigated: charcoal produced from Radiata pine plantation forestry; charcoal produced from Mallee eucalypt revegetation on agricultural land; and metallurgical coal. Impact indicators analysed include land-use, employment, workplace health & safety and a qualitative analysis of identified stakeholder issues. The research finds that biomass alternatives are significant generators of direct employment at the regional level; have concomitantly higher rates of workplace injuries and represent a significant change in land-use. Charcoal produced from Mallee biomass planted as a conservation measure on farmland, however, has the benefit of representing a shared land-use that provides an additional farm revenue stream and assists dryland salinity management. The paper finds that full substitution of coal by pine or Mallee charcoal does not provide a unique solution for optimising the social performance of the energy supply alternatives across all indicators. [ABSTRACT FROM AUTHOR]

The Monsoonal North West (MNW) region of Australia faces a number of challenges adapting to anthropogenic climate change. These have the potential to impact on a range of industries, including agricultural, pastoral, mining and tourism. However future changes to rainfall regimes remain uncertain due to the inability of Global Climate Models to adequately capture the tropical weather/climate processes that are known to be important for this region. Compounding this is the brevity of the instrumental rainfall record for the MNW, which is unlikely to represent the full range of climatic variability. One avenue for addressing this issue (the focus of this paper) is to identify sources of paleoclimate information that can be used to reconstruct a plausible pre-instrumental rainfall history for the MNW. Adopting this approach we find that, even in the absence of local sources of paleoclimate data at a suitable temporal resolution, remote paleoclimate records can resolve 25% of the annual variability observed in the instrumental rainfall record. Importantly, the 507-year rainfall reconstruction developed using the remote proxies displays longer and more intense wet and dry periods than observed during the most recent ~ 100 years. For example, the maximum number of consecutive years of below (above) average rainfall is 90% (40%) higher in the rainfall reconstruction than during the instrumental period. Further, implications for flood and drought risk are studied via a simple GR1A rainfall runoff model, which again highlights the likelihood of extremes greater than that observed in the limited instrumental record, consistent with previous paleoclimate studies elsewhere in Australia. Importantly, this research can assist in informing climate related risks to infrastructure, agriculture and mining, and the method can readily be applied to other regions in the MNW and beyond. [ABSTRACT FROM AUTHOR]

• Quantile-quantile rainfall mapping methods are extended to improve streamflow simulations. • Extensions correct rainfall bias at multiple time scales and model rainfall autocorrelation. • Methods reduce bias in rainfall sequencing metrics for downscaled GCM simulations. • Methods reduce bias in streamflow simulations forced by downscaled GCM simulations. Global circulation models (GCMs) provide important insights into future climate change. Bias-correction of downscaled GCM output is integral to any hydrological investigations of climate change due to discrepancies between the statistics of downscaled GCM simulations and observations. Many bias-correction techniques have been developed to support hydrological applications. However, there have been few comparisons of the sensitivity of hydrological simulations to different bias-correction assumptions. This paper investigates the importance of two common assumptions: (i) simultaneously correcting bias at multiple time scales, and (ii) explicitly handling rainfall autocorrelation; in quantile mapping of downscaled GCM rainfall data for hydrological simulation. Four quantile mapping methods are applied to correct bias in dynamically downscaled reanalysis and historical GCM simulations of rainfall for 11 catchments in south-eastern Australia and the performance of bias-corrected rainfall and streamflow simulations is evaluated. All quantile mapping methods investigated can effectively eliminate bias in monthly and annual rainfall totals. Quantile mapping methods that consider differences in the temporal dependence (autocorrelation) structure of downscaled GCM and observed rainfall are most effective in reducing bias in rainfall sequencing statistics, such as probability of consecutive wet or dry days. Streamflow simulations of mean and high streamflow percentiles are underestimated when generated using rainfall that is corrected using quantile mapping methods that do not consider differences in the temporal dependence structure of downscaled GCM and observed rainfall. Future hydrological investigations of climate change should therefore adopt methods that explicitly consider the temporal dependence structures of downscaled GCM and observed rainfall. [ABSTRACT FROM AUTHOR]

• We modify a method to assess yield of carryover reservoir with environmental flow. • The method can be applied at large scales, under historic and future climates. • We quantify yield declines due to climate change and environmental flow provision. Protecting freshwater systems to ensure sustainability requires diagnosing threats over a broad range of scales, from local to global. There is growing acceptance that environmental flows must be protected to sustain river channels and floodplain ecosystems downstream of reservoirs. Meeting environmental water requirements has proven difficult because they reduce water yield available for human use – a particular challenge in regions already experiencing declining water availability with climate change. A further challenge is the difficulty of assessing the impact of environmental water requirements on water availability for other purposes. This paper provides a modification of the Gould-Dincer method to assess the yield of carry-over reservoirs subject to environmental water requirements. The method characterizes reservoir inflows using readily available flow characteristics (annual mean and C v). We develop and test the method using ten examples with well-understood environmental water requirements and a range of annual flow C v s. We then demonstrate this method at continental scale, to investigate the impact on yield of providing high-reliability supply including environmental water requirements, under a changing climate. According to our results, considering climate change and environmental flow provision simultaneously, the decline in water yield is projected to be about 27% and 18% respectively for Australia and US (based on hypothetical reservoirs capacity of one times mean annual inflow). Adapting environmental flow demands to future hydrological conditions results in a 2% and 3% increase in Australia and US-wide yield for human use respectively. While further testing is needed, the method provides a simple and rapid way to estimate the impact of providing environmental flow on yield, applicable at global scale. [ABSTRACT FROM AUTHOR]

The last decades have witnessed a rapid development of green building developments at a global scale, as a measure to deal with various challenges related to climate change especially environmental issues. Australia is no exception. It is not unusual that extra resources such as cost are required for developing green buildings compared to conventional buildings. To justify extra upfront resources required for green building developments, a variety of tools have been developed such as life cycle assessment and life cycle costing. These two tools have been used in some projects in order to evaluate the cost and benefits of green buildings from a life cycle perspective. However, the uptake of life cycle assessment and life cycle costing are generally slow in the construction industry. This paper presents a critical review of green building evaluation from life cycle perspective. In particular, the use of life cycle assessment and life cycle costing in green building evaluation in Australia is reviewed. Knowledge gap is presented and future research agenda is proposed. [ABSTRACT FROM AUTHOR]

“Integrated Urban Water Management plans” consider all water services simultaneously to determine optimal infrastructure solutions. They create many benefits, including unlocking opportunities for water reuse. This paper conducts preliminary assessment of nine IUWM plan case studies from Melbourne. It finds inconsistencies between plans in relation to environmental and liveability objectives, and option identification methods, and also that many IUWM options perform worse than conventional water supplies in regards to energy. The most consequential finding is that the plans do not include scenario planning and therefore fail to consider infrastructure performance regarding resilience to future uncertainties around population and climate change. [ABSTRACT FROM AUTHOR]

A rapidly warming planet provides a significant challenge to the design, delivery, and maintenance of habitable housing across Australia. Information on the adequacy of current measures for cooling Indigenous houses in regional and remote communities in relation to climate change and rising energy consumption costs is lacking. Such information is needed to better protect low socio-economic status householders, people with pre-existing health conditions, and people living in climatically exposed regions. This article models the thermal performance of both existing and 'improved' (built to current national construction code standards) housing stock in relation to various occupancy density, cooling system, and ventilation practice scenarios. This modelling was undertaken for housing in Australia's tropical, arid, and hot/mild climate zones, matching the sites where most discrete Indigenous communities are located. Results show that retrofitting existing housing stock and even building new stock to meet recommended standards are not adequate measures for current or future climate changes. This paper challenges current knowledge, policy, and practices regarding Indigenous housing, demonstrating that significant reform is necessary to maintain habitable conditions and improve energy resilience. [ABSTRACT FROM AUTHOR]

International Ocean Discovery Program (IODP) Expedition 369 recovered a stratigraphically complete, Santonian-aged, pelagic sedimentary sequence at Site U1513 on the Naturaliste Plateau (33°47.6084′S, 112°29.1338′E) at ~2800 m water depth. The site was located at ~60°S paleolatitude in Cretaceous times. A total of 59 samples studied from Holes 1513A and 1513B yielded 140 calcareous and nine agglutinated benthic foraminiferal taxa. Gavelinellids (Notoplanulina, Gavelinella, Anomalinoides) and Gyroidinoides spp., are the most abundant taxa overall and also dominate most samples. We also report 382 foraminiferal stable isotopic measurements and infer cooling [of ~5 °C in surface waters and 2 °C at the seafloor] based on changes in δ18O values for benthic and planktonic taxa through the Santonian at Site U1513. Inferred cooling was accompanied by changes in planktonic and benthic foraminiferal assemblages. At Site U1513, benthic foraminiferal taxonomic richness declines by 15 species (from 20– 25 to 5–10 taxa) towards the upper Santonian. Within this interval, epifaunal, oxic foraminifera diminish in absolute and relative abundance, and there is a parallel relative increase in opportunistic taxa and infaunal foraminifera. Changes in benthic foraminiferal communities indicate a shift from oligotrophic to eutrophic conditions in the bottom water despite the general cooling trend. This paper explores the causes and effects of the paleoenvironmental changes in the bottom waters. • surface and bottom waters were differently affected by the Santonian cooling. • Ecologic groups within benthic and planktonic foraminifera show different reactions to pronounced cooling. • surface dwelling planktonic foraminifera record cooling by ~5 °C. • the seafloor cooled by ~2.5 °C during the onset of the Late Cretaceous cooling. [ABSTRACT FROM AUTHOR]

This paper presents a meta-analysis of 689 luminescence age estimates of Australian desert sand dunes. This analysis had two aims: to examine the hypothesis that Quaternary climate changes have forced dune accumulation, and to understand longitudinal dune behaviour from the age-architecture of sand dunes for which stratigraphic information is often absent or poorly known. A novel approach to the analysis of probability density curves of dune age frequency shows that in the Mallee dunefield of southeastern Australia only the period leading up to and including the last glacial maximum (LGM) (18–34 ka) experienced marked dune growth which cannot be explained by random stochastic activity. During the LGM, most, but not all, Mallee longitudinal dunes were accumulating more rapidly than before and after. In the Strzelecki dunefield source-bordering (SBD) longitudinal dune TL ( n = 61) and OSL ( n = 40) ages are more frequent at the Pleistocene–Holocene transition but nearby non-SBD longitudinal dunes ( n = 21 ages) were only active above background levels during the LGM. However, the Strzelecki dune age data set suffers from being drawn from a small number of individual dunes (10 SBD dated using TL; 12 SBD dated by OSL; 7 non-SBD dated by OSL) with a marked bias away from surficial (young) and basal (old) depths. Even during the LGM, many dunes do not record active growth and the dunefield was most likely a mosaic of stable dune surfaces and bare mobile patches, supported by the scant pollen data from the arid zone. Hyper-aridity has not been experienced in these dunefields. These vegetated dunes exhibit conservative behaviour with limited response to the range of climate forcing experienced in the late Pleistocene. A more complete understanding of dunefield response to Quaternary climates would require an intensive and structured dating program to overcome the ‘noise’ from stochastic processes leading to small-scale activity in these dunes and the simultaneous removal of parts of the sedimentary record. [ABSTRACT FROM AUTHOR]

Monitoring changes in the terrestrial carbon cycle and vegetation health can only be undertaken over large areas and on a regular basis using ecological indicators derived from satellite-based sensors. Climate conditions in Mediterranean ecosystems have undergone, and are projected to undergo, significant change in the future with marked impacts on forest and shrubland vegetation. In the southwest of Australia (SWAU), endemic tree species have experienced significant declines in health and mortality since the early 1990s primarily due to these climatic changes. In this paper we examine trends in Net Primary Production (NPP) from 2000 to 2011 as an indicator of productivity and health condition of the woody vegetation across the SWAU region. To do so, we examine NPP estimates derived from satellite imagery and climate data to answer the questions: (1) what is the extent and rate of change in NPP for the SWAU region over the study period, and (2) how important is fire as a contributing factor in the observed trends? Our results suggest that, similar to the global trend in Mediterranean ecosystems, between 2000 and 2011, overall NPP declined across the study region, with the majority of declines occurring in the ecological transition zone between trees and shrubs. Twenty-six percent of the 37,042 square kilometre of woody vegetation that showed a declining NPP trend, was affected by fire. The overall rate of NPP decline for the region was estimated to be −0.38 megaton C per year since 2000, indicating a reduction in the capacity of the region to act as a carbon sink. Under climate change projections, the observed decline trends are likely to continue and our results suggest that the carbon storage potential in this region is gradually decreasing following an ecological shift from tall tree-dominated to lower shrub-dominated vegetation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Wildfires are becoming more severe and frequent and their effects increasingly expose water resources to stress. • Climate, wildfire, streamflow records (1975 to 2018), topography, and landcover data from 92 catchments were combined to quantify the contribution of wildfire to streamflow variability across Australian temperate forests. • On average wildfire regimes relatively results in 8.8% increases in streamflow across Australian temperate forests. • Wildfire effects on regional streamflow varied spatially depending on hydroclimate factors, particularly precipitation. As wildfires become more frequent and severe, there are concerns regarding their impacts on water yield from forested catchments. While there are many studies in Australia about the effects of individual wildfires on streamflow at fine scales (<1 km2) in specific geographic settings, the effects of wildfire regimes on streamflow at broad spatial scales across temperate forests in Australia are not well understood. In this paper, we combined climate, wildfire, streamflow records (1975 to 2018), topographic, and landcover data from 92 catchments (74 – 4740 km2) in the Australian temperate zone to quantify the contribution of wildfire regimes over time to streamflow variability in different hydroclimatic settings (humid, dry sub-humid, and semi-arid) and geographic regions (Southeast Australia (SEA), Southwest Western Australia (SWWA), and Tasmania (TAS)). Wildfire regimes were represented by two metrics: the burnt area to drainage area (BDA) ratio for wildfire events in each year and a spatially averaged metric of Time Since Fire (TSF), which is a spatial average of time since the last wildfire in the catchment. By comparing prefire and postfire runoff ratios our study found that on average there was a short-term increase in runoff ratio (∼3% in year 1 and ∼6% in year 2 post-fire) after wildfires with BDA > 25%. No influence of fire was found in the long-term (15–20 years after the wildfire) runoff ratio. We found that wildfire regime, measured by TSF, explained ∼8.8% of the variation in annual streamflow across the Australian temperate zone, and that with decreasing TSF (i.e., increased wildfire impact), the average streamflow increased. Streamflow variation explained by wildfire regimes varied with hydroclimate. The explained variance of streamflow by wildfire regimes in semi-arid catchments (23%) and dry sub-humid catchments (13%) were higher than humid catchments (5%). Our results provide a broad-scale understanding of how wildfire regimes influence streamflow variability at broad temporal and spatial scales, and provided important context and baseline information for determining the implications of changes in climate and fire regimes for regional water availability. [ABSTRACT FROM AUTHOR]

Australia’s agriculture industry, particularly in the north, is characterised by supply chains of long travel distances, often in excess of 2500 km and costing up to 35% of farm gate price. Such travel distances increase the vulnerability of the industry to climatic variability and extreme events. Infrastructure investments in roads, bridges, processors and storage, along with changes in policy, have the potential to substantially reduce costs and increase resilience of the agriculture industries. In this paper, we outline the model, TRAnsport Network Strategic Investment Tool (TRANSIT) which is based on ArcGIS, and utilizes the Origin to Destination Cost Matrix solver within the Network Analyst toolkit. TRANSIT estimates the transport costs for all movements between enterprises, accommodating road conditions, vehicle types, vehicle access restrictions and regulatory requirements. TRANSIT was applied to the northern Australia livestock industry, consisting of 12 million cattle across 10,000 enterprises and 89,000 unique trips between these enterprises. Its ability to estimate the transport benefits from road upgrades, new processing facilities and biosecurity changes are shown using three priority case studies identified by industry and government. [ABSTRACT FROM AUTHOR]

Cities must transform in order to address the challenge of climate change and to achieve societal ambitions such as the sustainable development goals. However, a key impediment to achieving transformation is underdeveloped understandings of how key actors and sectors within the built environment work together to achieve goals. This paper addresses these gaps by developing and visually presenting a process map to describe: the key processes involved in producing the built environment across its life stages; key sectors of the built environment, their key actors, and the activities coordinated between them. The process map was peer reviewed by an expert reference group of built environment professionals active in Australia and the UK. The motivation for developing this process map is to facilitate future research to identify and expedite opportunities for coordinated action to address significant societal challenges such as climate change action, and the sustainable development goals – which require transformative action in cities. • Cities must transform to address climate change • We develop a process map to describe the production of the built environment • Process map describes fundamental activities for producing the built environment • Process map spans built environment life stages; identifying activities and interactions of key sectors and actors • Can be applied to inform transformative action targeted at challenges such as climate change [ABSTRACT FROM AUTHOR]

Due to significant weather variabilities of rainfalls, potential water savings through rainwater tanks are expected to vary significantly. Moreover, within some large cities, significant spatial variations are reported. With the emerging impacts of climate change, existing weather and spatial variabilities of potential water savings are also likely to be changed, which are unknown to the end-users. This paper presents the impacts of climate change on current weather and spatial variabilities of potential water savings for Adelaide, a large city in Australia. Future daily rainfall data was collected from a data portal provided by the Australian government derived through a statistical downscaling modelling. Projected daily rainfall data was fed to an earlier developed daily water balance model (eTank) to calculate water savings for three future periods; 2030–2050, 2055–2075 and 2080–2100. Three weathers (dry, average and wet) in each period were considered along with two climate change scenarios (RCP 4.5 and RCP 8.5) and two tank sizes (5 kL and 10 kL). It is found that varying outcomes without any general trend are expected depending on the projection scenario, period and weather condition. Contrary to the general perception, it is found that in several cases, the potential water savings are expected to increase compared to the current climate. Most of those expected increases in water savings are attributed to the projection scenario of RCP 4.5, in the near future and in dry years. In the far-future and with the projection scenario of RCP 8.5, most of the potential water savings are expected to decrease compared to the current climate. Regarding changes in spatial variability of water savings, it is found that the spatial variability will decrease in the near future, but will increase towards the far future. [ABSTRACT FROM AUTHOR]

Urbanisation continuously imposes pressure on coastal brownfield sites. At the same time, climate change and associated consequences on coastal environments make these sites less secure for human habitation. Converging stresses make the renewal process of these sites challenging, to the extent that they are often perceived as wicked problems. Several scholars suggest that temporary best solutions are identifiable to address wicked problems via an Adaptive , Participatory and Transdisciplinary (APT) approach. This paper operationalises the APT framework by evaluating the development of a strategic land-use framework for the transformation of a coastal brownfield site in southern Victoria, Australia. Policy and planning documents and in-depth interviews conducted with key stakeholders were analysed. Results show that the process incorporated elements of the APT approach by engaging with diverse stakeholder views during consultation and included community appraisal of alternative scenarios. However, the process fell short of being truly transdisciplinary or collaborative as it separated disciplinary inputs in decision-making. As a result, it did not appear to influence the final plan to achieve adaptive and responsive outcomes. We conclude that a uniquely placed-based and adaptive response can be created when all stakeholders deeply and effectively collaborate to develop shared understandings of the problem and co-create shared responses. We demonstrate that an integrated APT framework, one that focuses on synergies between A, P and T, can provide a useful tool for assessing the decision-making process of complex projects. Furthermore, our recommendations to advance APT can help directing future decision-making processes in similar projects with wicked problems. Unlabelled Image • Coastal brownfield transformations pose wicked challenges to decision makers. • An analytical framework for operationalising the Adaptive, Participatory, and Transdisciplinary (APT) approach was developed. • The APT framework was tested to evaluate a coastal brownfield transformation in Australia. • Suggestions were made for an integrated APT decision making approach. • For a uniquely placed-based and adaptive response, stakeholders should deeply collaborate to co-create shared responses. [ABSTRACT FROM AUTHOR]

Mesoscale eddies drive variability in phytoplankton functional trait composition and primary productivity (PP) relative to adjacent waters. Offshore waters in southeast Australia are subject to substantial mesoscale eddies that form when the East Australian Current (EAC) travels poleward along the coast, forming distinctive habitats in the upper ocean. Eddies provide an important enrichment mechanism in the nitrogen-limited waters of the Tasman Sea, yet there is limited knowledge of PP within cold- and warm-core eddies in the region and how physico-chemical and biological factors affect phytoplankton communities in this variable environment. We addressed the scarcity of observations by quantifying net PP using 13C isotopic enrichment incubations of surface waters over 10 degrees of latitude, comparing phytoplankton species composition in five different environments: a coastal shelf station, an oceanic cold and warm-core eddy, and a coastal dipole. Cold-core (cyclonic) eddies were significantly more productive than their warm-core (anticyclonic) counterparts (∼35 versus 0 mg C m−3 d−1), with centric diatoms the most prominent phytoplankton group, with a relatively high centric:pennate ratio. The diffuse attenuation coefficient, K d (PAR), and silicate were the best overall predictors of phytoplankton composition, explaining 88% of variation based on pigment analysis and size fractionation. Variance in net PP did not correlate significantly with physico-chemical parameters frequently used in PP models (temperature, K d [PAR], Chl a), yet inclusion of size-fractionated Chl a generated substantial improvement in our statistical model (from 36 to 77%). We show that cold-core eddies play a key role in regulating PP in eastern Australian waters and highlight a need for eddy-resolving models to incorporate descriptors of phytoplankton size structure to improve the accuracy of PP forecasts in eddy intensive regions. • Mesoscale eddies modulate primary productivity dynamics along the East Australian coast. • Knowledge of phytoplankton size structure improves prediction of primary productivity. • Phytoplankton community structure can be predicted from light and silicate levels. • Centric diatoms are the most prominent phytoplankton group in East Australian cyclonic eddies. [ABSTRACT FROM AUTHOR]

The Quaternary is well known for being a period of the geological record that saw significant and alternating climatic fluctuations. Here, we concentrate on the last 94 millennia that saw Australia and its surrounding seas undergo significant environmental changes. Importantly also it is during that this period of time includes the arrival and settlement of humans in Australia. Following on from Marine Isotopic Stage 4 (MIS4) that saw, over the period of 71-59 ka BP, a significant eustatic sea level drop (∼100 m), low sea-surface temperatures as well as glacial conditions on land, Australia experienced wet conditions again, but eventually progressively entered into a glacial phase. By then, humans had arrived on this large continent and later the megafauna progressively became extinct. This paper describes in detail the climate over this period, based principally on the high-resolution record of two marine sediment cores located offshore of the southern Australian margin, and that are then compared with known events on land as well as other deep-sea cores. Particular emphasis is placed on the period that spans the Last Glacial Maximum (LGM), the extent of which thus far had been poorly defined in the Australian region. Emphasis is placed on the period from 34 to 14 ka to demonstrate that (1) the LGM, defined here as the period 24 to 18 ka, was not always extremely dry and cold, and (2) that people were able to live in inland Australia as water existed in places, despite generally cold conditions. We also show using a series of ten maps - at 2 ka intervals over the 34-14 ka period - the waxing and waning of oceanic fronts such as the Subtropical and Subantarctic Fronts, link sea-surface temperatures (SST) with periods of glacial expansion in the Australian Alps and Tasmania, as well as the South Island of New Zealand, and the extent of the Leeuwin Current down to south of Australia. Aeolian dust was transported at sea over the main core site from ∼26 to 18 ka period, pointing to arid conditions in Australia, but this period was punctuated by two significant reductions in dust transport to both core sites, coinciding with a retreat of the Subantarctic Front away from the Australian southern coastline, and slight SST shifts for a few centuries at ∼24 and 22-21 ka BP. At the peak of the cold phase, from 23 to 18.4 ka, summer SST were of the order of 9 °C below that experienced during the middle of the Holocene at about 6 ka BP. A similar temperature drop was also experienced offshore the northwestern corner of Western Australia. Periglacial activity dates for the Australian mainland and Tasmania pool around ∼22 ka. On either side of the 24 ka event, the chain of lakes in the Willandra Lakes retained water and human activity was registered in the area. Elsewhere in Australia, water was present to sustain human populations during the cold and dry times. It is postulated here that northern Australia was at times quite wet, especially during MIS4. The cessation of the LGM is set on 18.4 ka from offshore southern Australia as confirmed for the deep-sea cores by several proxies, and more likely at 18 ka inland. Finally, we document that it took two millennia for "glacial" conditions to end in the Australian region as registered in our deep-sea core records, well after the lowest global sea level ∼20.6 and 20 ka, respectively, started to rise. There is also evidence of another very cold period determined on the Australian mainland, Tasmania and the South Island of New Zealand centred around 27 ka, after which time warmer conditions occurred before the start of the LGM. This is matched with our deep-sea records with very cold conditions and changes in oceanographic conditions. • 2 deep-sea cores provide information on the waxing and waning of oceanic fronts south of Australia. • The Last Glacial Maximum for the Australian region spans 24-18 ka. • 10 maps detail conditions in the Australian region spaning the period 34–14 ka. • Environmental conditions for MIS2 & MIS4 are compared in great detail in the cores. • Australia was arid and cold during the LGM but there was water to support human occupation. [ABSTRACT FROM AUTHOR]

Mixed crop-livestock farming systems provide food for over half of the global population. However, some important food exporting countries, like Australia, are predicted to be vulnerable to climate change and may require transformative adaptations if they are to continue their role in food exportation. This paper assesses the potential impacts of projected climate change by 2030 (0.4–1.6° increase in mean temperature) on Australian mixed crop-livestock systems and examines the consequences of shifts in land allocations to cropping and grazing, in these systems, as an adaptation option. Farm bio-economic simulation models were developed for these mixed enterprise systems in several regions of Australia. These models were based on biophysically coupled crop, pasture, and livestock simulation models that in turn drew on site-based downscaled climate projection datasets. The farm models calculated farm profitability and risk measures. A range of land use changes was investigated. At drier locations facing adverse climate change, results showed a transition towards a greater emphasis on livestock production could be beneficial when assessed against multiple criteria of farm profit, downside financial risk, and environmental damage. We highlight some industry and government actions and policies that could facilitate these preferred adaptation strategies at such locations. • Temperature increase of 0.4–1.6° affect mixed crop-livestock systems in Australia. • Transition towards a greater emphasis on livestock production is often desirable. • Financially optimal land allocations vary between historical and future climate. • Increase in the land devoted to pasture is a strategy to manage future climate risk. [ABSTRACT FROM AUTHOR]