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Many parts of Australia have experienced their worst single- and multi-year droughts on record over the last decade. These recent climate conditions have severely stressed our water supply systems and the communities that depend on them. With the threat of climate change potentially further exacerbating droughts in the years ahead, Engineers Australia firmly believes that: (i) A national review of the adequacy of drought response plans is urgently required. A recent national overview of long-term water resources planning by the Academy of Technological Sciences and Engineering (ATSE, 2007) revealed large inconsistencies and inadequacies in the standard of that planning. Based on the knowledge of the authors of this paper, similar outcomes are expected in the area of drought response planning. The scope of the review should include assessment of the transparency and defensibility of the timing of implementation of drought response actions; (ii) Continuing investment is needed in climate research to better understand the underlying drivers of our climate variability and their interactions at a range of time scales. The majority of research to date has focused on short -term sea surface temperature or pressure differentials across the globe (eg. the El Niño/Southern Oscillation) without understanding the longer-term drivers behind these temperature and pressure responses, which are being investigated through the Indian Ocean Climate Initiative and, more recently, the South East Australia Climate Initiative. This investment should include consolidation for and communication to the water industry of existing knowledge of links between long-term climate variability and key climate drivers including Earth’s orbital cycles, solar activity, atmospheric chemistry, major volcanic eruptions, surface and deeper ocean circulations (including the thermohaline circulation – the “great ocean conveyor belt”), sea ice, and major bush fires; (iii) Greater collaboration is required between climatologists, paleoclimatologists and water resource engineers to take advantage of recent scientific advances that have direct implications for drought response planning. Engineers Australia proposes that the National Water Commission should conduct a national forum to bring these three industry groups together with the aim of providing meaningful, useful advice to water industry practitioners from the latest climate research and to guide research activities towards more practical outcomes. This will enable water resource planners to better understand natural climate variability in the longer term and appropriately take into account greenhouse gas induced climate change, including an understanding of uncertainties surrounding both current and future climate; (iv) The development of an industry standard end-use demand model for urban areas should be accelerated. The absence of an industry standard tool in this area currently inhibits the ability to rapidly assess the financial costs of imposing restrictions on particular sectors of the community versus supply augmentation costs to avoid those restrictions. Such a tool is needed to make informed decisions about preparedness to pay for new infrastructure to avoid or reduce restrictions; and (v) More sophisticated water products and market mechanisms have a strong role to play in better managing scarce resources between similar types of users during times of drought. This has become increasingly important with demand hardening over recent decades, which has reduced the water savings that are achievable from water restrictions. Any expansion of water markets as a drought management tool must, however, occur within a regulatory framework that seeks to achieve equitable social outcomes by acknowledging the inherent social value of water to communities and the food security value of water to the nation. It is acknowledged in preparing this position paper that our understanding of drought and our responses to it are rapidly changing, particularly in light of climate change. This is particularly the case with the current reviews of aspects of the National Drought Policy, which were being undertaken by several government agencies at the time of drafting this paper. It is hoped that this position paper will encourage both greater dialogue and investment in drought forecasting, planning, adaptation and mitigation to enable Australia to be well placed to cope with future climate conditions. [ABSTRACT FROM AUTHOR]

This paper introduces a new approach to stochastically generating rainfall sequences that can take into account natural climate phenomena, such as the El Niño–Southern Oscillation and the interdecadal Pacific oscillation. The approach is also amenable to modeling projected affects of anthropogenic climate change. The method uses a relatively new technique, empirical mode decomposition (EMD), to decompose a historical rainfall series into several independent time series that have different average periods and amplitudes. These time series are then recombined to form an intradecadal time series and an interdecadal time series. After separate stochastic generation of these two series, because they are independent, they can be recombined by summation to form a replicate equivalent to the historical data. The approach was applied to generate 6-monthly rainfall totals for six rainfall stations located near Canberra, Australia. The cross correlations were preserved by carrying out the stochastic analysis using the Matalas multisite model. The results were compared with those obtained using a traditional autoregressive lag-one [AR(1)], and it was found that the new EMD stochastic model performed satisfactorily. The new approach is able to realistically reproduce multiyear–multidecadal dry and wet epochs that are characteristic of Australia’s climate and are not satisfactorily modeled using traditional stochastic rainfall generation methods. The method has two advantages over the traditional AR(1) approach, namely, that it can simulate nonstationarity characteristics in the historical time series, and it is easy to alter the decomposed time series components to examine the impact of anthropogenic climate change. [ABSTRACT FROM AUTHOR]

There is currently a distinct gap between what climate science can provide and information that is practically useful for (and needed by) natural resource managers. Improved understanding, and model representations, of interactions between the various climate drivers (both regional and global scale), combined with increased knowledge about the interactions between climate processes and hydrological processes at the regional scale, is necessary for improved attribution of climate change impacts, forecasting at a range of temporal scales and extreme event risk profiling (e.g., flood, drought, and bushfire). It is clear that the science has a long way to go in closing these research gaps; however, in the meantime water resource managers in the Murray-Darling Basin, and elsewhere, require hydroclimatic projections (i.e., seasonal to multidecadal future scenarios) that are regionally specific and, importantly, take into account the impacts, and associated uncertainties, of both natural climate variability and anthropogenic change. The strengths and weaknesses of various approaches for supplying this information are discussed in this paper. [ABSTRACT FROM AUTHOR]

Abstract: The “Big Dry”, a prolonged dry period in Australia from 1997 to 2009, dried out much of the Murray-Darling Basin (MDB) and resulted in large agricultural losses and degraded river ecosystems. Climate projections are that dry conditions in the MDB are likely to be more regular and severe than ever before, and recent policy initiatives are likely to reduce consumptive water use and redirect water to ecosystem management. This paper aims to develop an understanding of the interactions between water policy and irrigation practices by deriving lessons from drought management in irrigated agriculture of the MDB during the Big Dry, and furthermore, to draw out lessons to enhance the preparedness of irrigated agriculture for a future drier climate and reduced water availability. Reviews of irrigation farmers’ practices, attitudes and capacity to manage during prolonged droughts in the MDB, and the evolution of agricultural water policy in Australia since 1990 were made. It is clear that farmers could be better prepared to deal with a drier climate if their water management practices, e.g. irrigation methods and soil moisture measuring tools are improved, if the impediments to the uncertainty of water allocation and low water availability could be overcome, and if well-targeted research and extension could assist farmers to use water more wisely. It is also clear that Australian water policy could be better prepared in terms of assisting irrigated agriculture to deal with a drier climate. Key areas are reduction of barriers and distortions to water trading, optimizing the environmental water allocation, and seeking mutual benefits between environmental water allocation and irrigated agriculture, improvement of the cost-effectiveness of investments in water supply infrastructure, facilitating carryover and capacity sharing at larger scales, and provision of accurate, accessible and useful water information at different scales. An approach to irrigation practice and water policy is proposed based on past experience and potential opportunities. The approach is a set of linked strategies for more robust agricultural production and a more sustainable environment under a drier climate and reduced water availability. [Copyright &y& Elsevier]

Australia's rivers are among the most variable in the world and this has been a major challenge in catchments such as the Murray-Darling Basin where management has focused on increasing agricultural production while reducing risks from fluctuating water availability. Pressure for development and over-optimistic assessments of available water have resulted in over-allocation and increasing ecological decline, which has been severely exacerbated by record-breaking drought. In recent years, governments have agreed to radical policies such as the National Water Initiative 2004 and allocated substantial funds in response. Implementation is in gridlock, however, as the socio-economic implications have become clearer. Most debate is focused on the draft Murray-Darling Basin Plan due for release in mid-2010 before finalization in 2011. It will be the first Basin-wide plan and is intended to deal with inequities across borders and risks such as climate change and drought. Climate change scenarios for 2030 foresee a range of potential surface water availability outcomes, ranging from a 7% increase to a 37% decrease, yet greater water scarcity is being experienced in the current (2002+) drought with inflows reduced by 70% or more in extreme years. Contradictory policies are hindering the more open adaptation required to manage a drier future. [ABSTRACT FROM AUTHOR]

• Climate change and building load variations may impact optimised building designs. • A method using climate models and optimisation is used to optimise future buildings. • A case study is conducted on two cities in Australia: Canberra and Brisbane. • Results show that optimising for future climates can save energy for Canberra. • For Brisbane, savings are small and the present-optimised design seems acceptable. Building energy optimisation is generally performed under present climate conditions with fixed simulation parameters (e.g. internal loads). However, climate change and variations in simulation parameters over the building's life span may impact the optimised design. A key question is whether a particular energy-optimised design under present climate conditions would remain energy-optimised in the future. Accordingly, in this paper, a new simulation-based optimisation method is developed, which uses climate models and Ant Colony Optimisation to compare the energy-optimised designs under present and future climates. To demonstrate its potential, this method is applied to a typical office building in two Australian cities, Brisbane and Canberra. The results show that optimising under future climate conditions can lead to different optimal building designs. For Brisbane, the energy difference between optimising under present and future climate conditions is small, but in Canberra the cooling load is increased by up to 6%. This suggests that optimising the studied office building under present climate conditions is acceptable for Brisbane, while considering future climate may yield some savings in Canberra. Results also show that the energy-optimised building configuration for both future and present climates in Brisbane is less sensitive to changes in the load scenario than in Canberra. [ABSTRACT FROM AUTHOR]

Australia has one of the highest per capita rates of greenhouse gas (GHG) emissions in the world as well as one of the highest percentages of urban dwellers, focusing attention on the need for our cities to reduce emissions. This study estimates the GHG emission reductions that will be achieved by the first stage of Canberra's light rail network, which will commence operation in 2019. Compared to a business-as-usual case (no light rail), emissions will be reduced by 18–30% along the first stage corridor, depending on the size of the modal shift from private passenger vehicles to the light rail. Each Canberran who shifts from a motorcar to the light rail will essentially reduce their emissions for the journey by 100%. The decarbonisation of the journey comes from the sourcing by 2020 of 90% of Canberra's electricity, which will power the light rail system, from renewable sources and the requirement by the ACT Government that the light rail system source the remaining 10% of its electricity from renewable sources. [ABSTRACT FROM AUTHOR]

The planning and development of the national capital Canberra was the subject of wide discussion and reflection during its centenary year 2013. However much of the attention was on the original design competition (1911) and the city itself. This article explores a different and important dimension – the national capital in its regional context, the Australian Capital Region. A number of factors are considered including the early influence of geography and climate, the subsequent expansion of the metropolis and growing connections beyond the border on critical issues such as water, transport and urban settlement. Discussion is found on the challenges of implementing regional planning and the role of regional collaboration in responding to ‘wicked’ problems such as climate change. Conclusions are made on the opportunities to develop Canberra and the region into an international model for a sustainable region responding to the challenges of the twenty-first century. [ABSTRACT FROM AUTHOR]

The National Capital Canberra as a planned city has a unique system in Australia with direct federal planning controls combined with Australian Capital Territory (ACT) government administration integrating state and local functions. The immediate surrounding border of NSW is also a significant consideration in planning and land management. In its Centenary year, Canberra is reflecting on its planning heritage and in doing so exploring the planning challenges for the next 100 years. Key issues being discussed include climate change, renewable energy, public transport, regional development and demographic change. Recent initiatives include the introduction of light rail, green precincts and strengthening Canberra as a knowledge economy capitalising on the universities and national research institutions. The voices of the community are developing strongly and the planning system is being challenged to accommodate this change. This article will outline the major reforms in the planning system in the ACT in recent years and discuss whether these have provided a platform for a more sustainable future for Canberra as a national capital, a regional capital for the south-east NSW and as a local community expected to grow to half a million population by 2030. [ABSTRACT FROM AUTHOR]

Isolating the causes of extreme variations or changes in the hydroclimate is difficult due to the complexities of the driving mechanisms, but it is crucial for effective natural resource management. In Australia's Murray-Darling Basin (MDB), ocean-atmosphere processes causing hydroclimatic variations occur on time scales from days to centuries, all are important, and none are likely to act in isolation. Instead, interactions between all hydroclimatic drivers, on multiple time scales, are likely to have caused the variations observed in MDB instrumental records. A simplified framework is presented to assist natural resource managers in identifying the potential causes of hydroclimatic anomalies. The framework condenses an event into its fundamental elements, including its spatial and temporal signal and smallscale evolution. The climatic processes that are potentially responsible are then examined to determine possible causes. The framework was applied to a period of prolonged and severe dry conditions occurring in the southern MDB from 1997-2010, providing insights into possible causal mechanisms that are consistent with recent studies. The framework also assists in identifying uncertainties and gaps in our understanding that need to be addressed. [ABSTRACT FROM AUTHOR]

The study used a modelling approach to assess the potential impacts of likely climate change and increase in CO concentration on the wheat growth and water balance in Murray-Darling Basin in Australia. Impacts of individual changes in temperature, rainfall or CO concentration as, well as the 2050 and 2070 climate change scenarios, were analysed. Along an E-W transect, wheat yield at western sites (warmer and drier) was simulated to be more sensitive to temperature increase than that at eastern sites; along the S-N transect, wheat yield at northern warmer sites was simulated to be more sensitive to temperature increase, within 1-3°C temperature increase. Along the E-W and S-N transects, wheat at drier sites would benefit more from elevated [CO] than at wetter sites, but more sensitive to the decline in rainfall. The increase in temperature only did not have much impact on water balance. Elevated [CO] increased the drainage in all the sites, whilst rainfall reduction decreased evapotranspiration, runoff and drainage, especially at drier sites. In 2050, wheat yield would increase by 1-10% under all climate change scenarios along the S-N transect, except for the northernmost site (Dalby). Along the E-W transect, the most obvious increase of wheat yields under all climate change scenarios occurred in cooler and wetter eastern sites (Yass and Young), with an average increase rate of 7%. The biggest loss occurred at the driest sites (Griffith and Swan Hill) under A1FI and B2 scenarios, ranging from −5% to −16%. In 2070, there would be an increased risk of yield loss in general, except for the cool and wet sites. Water use efficiency was simulated to increase at most of the study sites under all the climate change scenarios, except for the driest site. Yield variability would increase at drier sites (Ardlethan, Griffith and Swan Hill). Soil types would also impact on the response of wheat yield and water balance to future climate change. [ABSTRACT FROM AUTHOR]

Climate change has potentially significant implications for hydrology and the quantity and quality of water resources. This study investigated the impacts of climate change and revegetation on water and salt balance, and stream salt concentration for catchments within the Murray-Darling Basin, Australia. The Biophysical Capacity to Change model was used with climate change scenarios obtained using the CSIRO DARLAM 125 (125 km resolution) and Cubic Conformal (50 km resolution) regional climate models. These models predicted up to 25% reduction in mean annual rainfall and a similar magnitude of increase in potential evapotranspiration by 2070. Relatively modest changes in rainfall and temperature can lead to significant reductions in mean annual runoff and salt yield and increases in stream salt concentrations within the Basin. The modelled reductions in mean annual runoff were up to 45% in the wetter/cooler southern catchments and up to 64% in the drier/hotter western and northern catchments. The maximum reductions in salt yield were estimated to be up to 34% in the southern catchments and up to 49% in the northern and western catchments. These changes are associated with average catchment rainfall decreases of 13 to 21%. The results suggest that percentage changes in rainfall will be amplified in runoff. This study demonstrates that climate change poses significant challenges to natural resource management in Australia. [ABSTRACT FROM AUTHOR]

Isotope geology began in the Department of Geophysics, the Australian National University, Canberra, in the late 1950s. A K-Ar dating laboratory was set up in 1960, with development of Rb-Sr dating facilities taking place soon after. These laid the foundations for extensive programs of isotopic dating with emphasis on providing quantitative age information related to the geological evolution of the Australian continent. Demonstration of progressive younging of granite emplacement to the northeast in the Tasman Fold Belt of eastern Australia was a notable initial achievement. Early successes on broader questions included the demonstration of the ability to measure K-Ar ages on young volcanic rocks, leading on to a significant role in the establishment of the geomagnetic polarity time-scale. In the early 1970s, dating of returned lunar samples by the Rb-Sr method was another most notable success. The development of the SHRIMP ion microprobe, commencing in the mid-1970s, resulted in U-Pb dating of zircon (and other minerals) becoming possible on very small areas of single crystals, revolutionising the approach to dating, with wide application not only to rocks in Australia, but indeed worldwide. Isotope geochemical study of the Earth's mantle and crust was also an important activity, especially in the 1980s. Subsequently, emphasis has been redirected toward studies of the Quaternary, including U-series isotopic dating as well as high-resolution isotopic and element ratio measurements, especially on corals, to track climate change. Many other developments in isotopic dating and isotope geochemistry have taken place over the last 45 years with installation and, in some cases, development of appropriate instrumentation, facilitating the updating of capabilities and expanding the range of techniques, continuing to the present time. [ABSTRACT FROM AUTHOR]