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This paper presents a method to analyze and improve the set of equations constituting a rainfall‐runoff model structure based on a combination of a data assimilation algorithm and polynomial updates to the state equations. The method, which we have called "Data Assimilation Informed model Structure Improvement" (DAISI) is generic, modular, and demonstrated with an application to the GR2M model and 201 catchments in South‐East Australia. Our results show that the updated model generated with DAISI generally performed better for all metrics considered included Kling‐Gupta Efficiency, NSE on log transform flow and flow duration curve bias. In addition, the elasticity of modeled runoff to rainfall is higher in the updated model, which suggests that the structural changes could have a significant impact on climate change simulations. Finally, the DAISI diagnostic identified a reduced number of update configurations in the GR2M structure with distinct regional patterns in three sub‐regions of the modeling domain (Western Victoria, central region, and Northern New South Wales). These configurations correspond to specific polynomials of the state variables that could be used to improve equations in a revised model. Several potential improvements of DAISI are proposed including the use of additional observed variables such as actual evapotranspiration to better constrain internal model fluxes. Plain Language Summary: This paper presents a data‐driven method to improve rainfall‐runoff models used to generate future water resources scenario in climate change studies. The method, which we have called "Data Assimilation Informed model Structure Improvement" (DAISI) is generic, modular, and demonstrated with an application to monthly streamflow simulations over a large data set of catchments in South‐East Australia. Our results show that DAISI improves model performance for a wide range of metrics and increases the sensitivity of the model to climate inputs, which is critical in climate change scenarios. Finally, the improvements identified by DAISI take a simple mathematical form with distinct regional patterns in three sub‐regions of the study domain (Western Victoria, central region, and Northern New South Wales). Several improvements of DAISI are discussed including the inclusion of additional observed variables such as evapotranspiration to better constrain model simulations. Key Points: Data Assimilation Informed model Structure Improvement method diagnoses hydrological model structures by combining data assimilation with a polynomial update of state equationsThe method was applied to the GR2M rainfall‐runoff model with significantly improved streamflow simulations in 201 Australian catchmentsThe method identified updates to state equations with marked regional characteristics that could guide future improvement of GR2M [ABSTRACT FROM AUTHOR]

Climate change has resulted in a worldwide increase in intensity and frequency of extreme weather events including bushfires. Previous research has shown that communities often do not engage in disaster preparedness, even when sufficient education and resources are provided. With the projected increase in natural disasters, preparedness is paramount, and more research is needed to gain an understanding into what impacts community preparedness in the face of climate change. This study investigated one rural Australian community's preparedness for the 2019–2020 bushfires. Thirteen Australian adults who resided within a small rural community in New South Wales during the 2019–2020 bushfires participated in semi-structured interviews. Data were analysed using inductive thematic analysis. Participants reported being unprepared for the 2019–2020 bushfires and that the community has started to prepare for future bushfires. However, they also described a belief in 'climate cycles' rather than climate change, limiting engagement in preparedness for future hazards. Participants also reported that they did not talk about the 2019–2020 bushfires, although described experiencing residual anxiety. Recommendations included support needed for rural communities to help with future preparedness efforts and mental health symptoms. [ABSTRACT FROM AUTHOR]

To quantify the climate change impacts of forestry and forest management options, we must consider the entire forestry system: the carbon dynamics of the forest, the life cycle of harvested wood products, and the substitution benefit of using biomass and wood products compared to more greenhouse gas intensive options. This paper presents modelled estimates of the greenhouse gas balance of two key native forest areas managed for production in New South Wales for a period of 200 years, and compares it to the option of managing for conservation only. These two case studies show that forests managed for production provide the greatest ongoing greenhouse gas benefits, with long-term carbon storage in products, and product substitution benefits critical to the outcome. Thus native forests could play a significant part in climate change mitigation, particularly when sustainably managed for production of wood and non-wood products including biomass for bioenergy. The potential role of production forestry in mitigating climate change, though substantial, has been largely overlooked in recent Australian climate change policy. [ABSTRACT FROM AUTHOR]

The cool temperate rainforests of eastern Australia are at risk from anthropogenic climate change with predicted changes in temperature, rainfall, severe weather, basal cloud layer, and droughts. Phenology and litter production are fundamental reproductive and growth processes to document in any ecosystem, yet very few long-term studies exist in Australian rainforests. In this study, long-term datasets are used to describe different phenological and litter production behaviours of tree species in a Nothofagus cool temperate rainforest in New South Wales (NSW), Australia, analysing seasonal and inter-annual climate drivers. Leaf fall at the community level was mostly influenced by Nothofagus moorei, driven by temperature and wind speed, and Ceratopetalum apetalum, driven by temperature, rainfall, and solar radiation. Mean dates of leaf fall at the community level were found to be advancing, correlated with an advance in solar radiation. We also analysed in detail the flowering behaviour of the dominant canopy tree species, N. moorei, which masts with a mean inter-flowering period of 3-4 years in 65% of flowering events. Three of the studied species presented mast flowering, C. apetalum, N. moorei, and Orites excelsus; however, they did not mast in the same years. All species presented strong seasonality in their phenological activity, but seasonality peaked in different months, and were driven by varied climate variables. Supra-annual peaks of flowering and fruiting did not occur at the same time for all species, and climate drivers of inter-annual phenological behaviour were different for each species. Our results show that projected changes in climate will affect species from cool temperate rainforests differently, affecting not only biomass production, but also species reproductive output and forest dynamics. [ABSTRACT FROM AUTHOR]

Globally, areas of high-quality wildlife habitat of significant environmental value are at risk of permanent damage from climate change. These areas represent social-ecological systems that will require increasing management intervention to maintain their biological and socio-cultural values. Managers of protected areas have begun to recognize the inevitability of ecosystem change and the need to embrace dynamic approaches to intervention. However, significant uncertainty remains about the onset and severity of some impacts, which makes planning difficult. For Indigenous communities, there are intrinsic links between cultural heritage and the conservation of place and biodiversity that need to be better integrated in protected area planning and management. In New South Wales, Australia, management of public conservation reserves and national parks is the responsibility of a State government agency, the National Parks and Wildlife Service (NPWS). This paper describes the outcomes of a participatory planning process with NPWS staff to, firstly, identify the options available, the available 'tool kit', to manage biodiversity and cultural heritage in protected areas; secondly, explore how the selection of management actions from the 'tool kit' is associated with the level of climate risk to biodiversity or cultural heritage assets; and thirdly, to understand how the form of individual management actions might adapt to changes in climate risk. Combining these three elements into a series of risk-based, adaptive pathways for conservation of biodiversity and cultural heritage is a novel approach that is currently supporting place-based planning for public conservation areas. Incorporation of the trade-offs and synergies in seeking to effectively manage these discrete but related types of values and the implications for conservation practice are discussed. [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]

The NARCliM project contributes to the CORDEX initiative for Australasia. The first generation of NARCliM (N1.0) used CMIP3 global climate models (GCMs) and provided near and far future estimates of climate change across Australasia at 50‐km and southeast Australia at 10‐km resolution under a business‐as‐usual climate scenario. However, multiple sets of 20‐year periods in N1.0 did not permit analysis of long‐term, inter‐annual to decadal trends across the 21st century. Feedback on user needs for regional climate information revealed the desire for multiple emission scenarios and use of newer CMIP5 GCMs for dynamical downscaling. These limitations led to development of the second iteration of NARCliM, namely NARCliM1.5 (N1.5). The N1.5 downscaling exercise uses CMIP5 GCMs and is temporally expanded to cover 150 years (1950–2100) for two future Representative Concentration Pathways (RCP4.5 and RCP8.5). N1.5 simulations remain at the 50‐km and 10 km resolutions over the same domains as N1.0, thus producing an expanded and complementary data set for regional climate change. N1.5 simulations substantially improve over N1.0 in capturing the seasonal patterns and magnitudes of precipitation, including improvements in overall bias. Conversely, N1.5 shows similar results to N1.0 for maximum and minimum temperature, with no substantial improvement in overall bias. N1.5 projections project a hotter and drier future relative to N1.0. The combined N1.0 and N1.5 ensemble provides a wider spread of future climates more representative of that found in the full CMIP5 ensemble. Together, N1.0 and N1.5 ensembles provide an improved, more comprehensive data set for studying climate change. Plain Language Summary: The second iteration of New South Wales and Australian Capital Territory Regional Climate Modeling (NARCliM) simulations (N1.5) are described, complementing original NARCliM (N1.0) simulations and expanding the ensemble to 24 members. N1.5 simulations substantially improve over N1.0 simulations in capturing the seasonal patterns and magnitudes of precipitation. N1.5 projections add information to the NARCliM ensemble including the potential for hotter and drier futures than those projected in N1.0. Together, the N1.0 and N1.5 ensembles provide an improved, more comprehensive data set for studying climate change. The varying model performances identified here will help the development of the next generation of regional climate simulations over Australia. Key Points: The second iteration of NARCliM simulations (N1.5) are described complementing original NARCliM simulations (N1.0)N1.5 simulations substantially improve over N1.0 simulations in capturing the seasonal patterns and magnitudes of precipitationN1.5 projections add information to the NARCliM ensemble including the potential for hotter and drier futures than those projected in N1.0 [ABSTRACT FROM AUTHOR]

The challenges of managing and conserving threatened species that have a widespread distribution operate at several levels and recovery of these species is a complex process. This paper provides an overview of how science is informing the management and conservation of the Grey-headed Flying-fox ( Pteropus poliocephalus) in New South Wales. It outlines a series of research projects and activities the Department of Environment and Climate Change (New South Wales) has led or been involved in since the Grey-headed Flying-fox was listed as threatened in New South Wales in May 2001. This includes investigation of the species’ distribution and abundance; its roosting and foraging habitat requirements; assessment of horticultural damage and the mitigation techniques used; public attitudes towards the species; and development of policies and plans to guide the species’ conservation and management. Conservation gains for threatened species can be achieved through a sustained, focused programme of management, coordinated by dedicated individuals and informed by the available science. Scientists, policy-makers and the general community must continue to strive together for the recovery of widespread, threatened species. [ABSTRACT FROM AUTHOR]

Understanding the physiological tolerances of ectotherms, such as thermal limits, is important in predicting biotic responses to climate change. However, it is even more important to examine these impacts alongside those from other landscape changes: such as the reduction of native vegetation cover, landscape fragmentation and changes in land use intensity (LUI). Here, we integrate the observed thermal limits of the dominant and ubiquitous meat ant Iridomyrmex purpureus across climate (aridity), land cover and land use gradients spanning 270 km in length and 840 m in altitude across northern New South Wales, Australia. Meat ants were chosen for study as they are ecosystem engineers and changes in their populations may result in a cascade of changes in the populations of other species. When we assessed critical thermal maximum temperatures (CTmax) of meat ants in relation to the environmental gradients we found little influence of climate (aridity) but that CTmax decreased as LUI increased. We found no overall correlation between CTmax and CTmin. We did however find that tolerance to warming was lower for ants sampled from more arid locations. Our findings suggest that as LUI and aridification increase, the physiological resilience of I. purpureus will decline. A reduction in physiological resilience may lead to a reduction in the ecosystem service provision that these populations provide throughout their distribution. [ABSTRACT FROM AUTHOR]

There is concern in Australia that droughts substantially increase the incidence of suicide in rural populations, particularly among male farmers and their families. We investigated this possibility for the state of New South Wales (NSW), Australia between 1970 and 2007, analyzing data on suicides with a previously established climatic drought index. Using a generalized additive model that controlled for season, region, and long-term suicide trends, we found an increased relative risk of suicide of 15% (95% confidence interval, 8%-22%) for rural males aged 30-49 y when the drought index rose from the first quartile to the third quartile. In contrast, the risk of suicide for rural females aged >30 y declined with increased values of the drought index. We also observed an increased risk of suicide in spring and early summer. In addition there was a smaller association during unusually warm months at any time of year. The spring suicide increase is well documented in nontropical locations, although its cause is unknown. The possible increased risk of suicide during drought in rural Australia warrants public health focus and concern, as does the annual, predictable increase seen each spring and early summer. Suicide is a complex phenomenon with many interacting social, environmental, and biological causal factors. The relationship between drought and suicide is best understood using a holistic framework. Climate change projections suggest increased frequency and severity of droughts in NSW, accompanied and exacerbated by rising temperatures. Elucidating the relationships between drought and mental health will help facilitate adaptation to climate change. [ABSTRACT FROM AUTHOR]

Haines, P.E. and Thom, B.G., 2007. Climate change impacts on entrance processes of intermittently open/closed coastal lagoons in New South Wales, Australia. Journal of Coastal Research, SI 50 (Proceedings of the 9th International Coastal Symposium), 242 – 246. Gold Coast, Australia, ISSN 0749.0208. Intermittently open/closed coastal lagoons are a relatively unique feature of the south-east Australian coastline, and NSW in particular. Future climate change is expected to modify a number of climate variables that define the physical and chemical structure and ecological behaviour of the NSW coastal lagoons. These climate variables include mean sea level, wave climate and rainfall behaviour (total depth and storm intensity). Entrance morphodynamic processes are particularly vulnerable to climate change. These processes, which describe the opening and closing cycle of these lagoons, are controlled by dominant coastal (wave and sea level) conditions and episodic catchment runoff events. The magnitude of entrance impacts will depend on the particular characteristics and location of individual lagoons. An increase in mean sea level is likely to move the entrance sand berm upward and landward. An increase in south-easterly waves will cause minor rotations in beach planform alignments with expected net erosion from southern ends of beaches and net accretion at northern ends. For lagoon entrances at the southern end of beaches, this will result in a net loss of sand from the entrance and a shortening of the entrance channel. For lagoon entrances at the northern end of beaches, this will result in a net growth of the entrance berm, possibly offsetting the recession resulting from mean sea level rise. Increased typical lagoon water levels behind the berm are also expected. Marine flood tide deltas may accrete vertically and more landward. A decrease in total rainfall depth is likely to retard the cycle of filling and draining, and reducing the frequency of entrance breakout for mostly closed lagoons. For mostly open lagoons, however, an increase in rainfall storm intensity may actually increase scour through the entrance, thus increasing the longevity of ocean connections. [ABSTRACT FROM AUTHOR]