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Declining winter rainfall coupled with recent prolonged drought poses significant risks to water resources and agriculture across southern Australia. While rainfall declines over recent decades are largely consistent with modelled climate change scenarios, particularly for southwest Australia, the significance of these declines is yet to be assessed within the context of long-term hydroclimatic variability. Here, we present a new 668-year (1350–2017 CE) tree-ring reconstruction of autumn–winter rainfall over inland southwest Australia. This record reveals that a recent decline in rainfall over inland southwest Australia (since 2000 CE) is not unusual in terms of either magnitude or duration relative to rainfall variability over the last seven centuries. Drought periods of greater magnitude and duration than those in the instrumental record occurred prior to 1900 CE, including two 'megadroughts' of > 30 years duration in the eighteenth and nineteenth centuries. By contrast, the wettest > decadal periods of the last seven centuries occurred after 1900 CE, making the twentieth century the wettest of the last seven centuries. We conclude that the instrumental rainfall record (since ~ 1900 CE) does not capture the full scale of natural hydroclimatic variability for inland southwest Australia and that the risk of prolonged droughts in the region is likely much higher than currently estimated. [ABSTRACT FROM AUTHOR]

Rainfall regimes in many parts of the world have become increasingly dominated by fewer, but more extreme, rainfall events. Understanding how tree growth responds to changes in the frequency and intensity of rain events is critical to predicting how climate change will impact on forests and woodlands in the future. In this study, we used five tree‐ring records of the native Australian conifer Callitris columellaris that span a large (> 20°) latitudinal and climatic gradient from the mesic (tropical) north to the xeric (semi‐arid) south of Australia to investigate how inter‐annual and spatial variation in the delivery of rainfall (the intensity and frequency of rain events) influences tree growth. In semi‐arid biomes (~300–400 mm rainfall annually), tree growth is most strongly related to the amount of rainfall from heavy (> 75th percentile) rain days or the number of extreme (> 90th percentile) rain days, regardless of differences in the seasonal distribution and average intensity of rainfall among sites. Our findings also indicate that there is likely a minimum threshold amount of daily rainfall (~5 mm) that is required to stimulate tree growth in the semi‐arid zone. In contrast, in the tropics (> 800 mm annual rainfall), inter‐annual variation in growth is best explained by total growing season rainfall or the number of rain days > ~5 mm (~50th percentile of rain days) rather than extreme rainfall. Our findings indicate that not all rain events are important for driving tree growth, which has important implications for interpreting climatic signals in tree rings. Our findings also indicate that projected increases in the intensity of extreme rain events are likely to have contrasting impacts on tree growth across biomes, with greater and positive impacts on growth in semi‐arid biomes and potentially negative impacts on growth in tropical biomes of Australia. [ABSTRACT FROM AUTHOR]

Globally, many biomes are being impacted by significant shifts in total annual rainfall as well as increasing variability of rainfall within and among years. Such changes can have potentially large impacts on plant productivity and growth, but remain largely unknown, particularly for much of the Southern Hemisphere. We investigate how growth of the widespread conifer, Callitris columellaris varied with inter-annual variation in the amount, intensity and frequency of rainfall events over the last century and between semi-arid (<500 mm mean annual rainfall) and tropical (>800 mm mean annual rainfall) biomes in Australia. We used linear and polynomial regression models to investigate the strength and shape of the relationships between growth (ring width) and rainfall. At semi-arid sites, growth was strongly and linearly related to rainfall amount, regardless of differences in the seasonality and intensity of rainfall. The linear shape of the relationship indicates that predicted future declines in mean rainfall will have proportional negative impacts on long-term tree growth in semi-arid biomes. In contrast, growth in the tropics showed a weak and asymmetrical ('concave-down') response to rainfall amount, where growth was less responsive to changes in rainfall amount at the higher end of the rainfall range (>1250 mm annual rainfall) than at the lower end (<1000 mm annual rainfall). The asymmetric relationship indicates that long-term growth rates of Callitris in the tropics are more sensitive to increased inter-annual variability of rainfall than to changes in the mean amount of rainfall. Our findings are consistent with observations that the responses of vegetation to changes in the mean or variability of rainfall differ between mesic and semi-arid biomes. These results highlight how contrasting growth responses of a widespread species across a hydroclimatic gradient can inform understanding of potential sensitivity of different biomes to climatic variability and change. [ABSTRACT FROM AUTHOR]

Tree-ring based climate reconstructions have been critical for understanding past variability and recent trends in climate worldwide, but they are scarce in Australia. This is particularly the case for temperature: only one tree-ring width based temperature reconstruction – based on Huon Pine trees from Mt Read, Tasmania – exists for Australia. Here, we investigate whether additional tree-ring parameters derived from Athrotaxis cupressoides trees growing in the same region have potential to provide robust proxy records of past temperature variability. We measured wood properties, including tree-ring width (TRW), mean density, mean cell wall thickness (CWT), and tracheid radial diameter (TRD) of annual growth rings in Athrotaxis cupressoides , a long-lived, high-elevation conifer in central Tasmania, Australia. Mean density and CWT were strongly and negatively correlated with summer temperatures. In contrast, the summer temperature signal in TRW was weakly positive. The strongest climate signal in any of the tree-ring parameters was maximum temperature in January (mid-summer; JanT max ) and we chose this as the target climate variable for reconstruction. The model that explained most of the variance in JanT max was based on TRW and mean density as predictors. TRW and mean density provided complementary proxies with mean density showing greater high-frequency (inter-annual to multi-year) variability and TRW showing more low-frequency (decadal to centennial-scale) variability. The final reconstruction model is robust, explaining 55% of the variance in JanT max , and was used to reconstruct JanT max for the last five centuries (1530–2010 C.E.). The reconstruction suggests that the most recent 60 years have been warmer than average in the context of the last ca. 500 years. This unusually warm period is likely linked to a coincident increase in the intensity of the subtropical ridge and dominance of the positive phase of the Southern Annular Mode in summer, which weaken the influence of the band of prevailing westerly winds and storms on Tasmanian climate. Our findings indicate that wood properties, such as mean density, are likely to provide significant contributions toward the development of robust climate reconstructions in the Southern Hemisphere and thus toward an improved understanding of past climate in Australasia. [ABSTRACT FROM AUTHOR]

This study sought to examine whether neighborhood social environment was related to patterns of depressive symptoms among primary care patients with type 2 diabetes mellitus (DM). Neighborhood social environment was assessed in 179 patients with type 2 DM. Individual patient residential data at baseline was geo-coded at the tract level and was merged with measures of neighborhood social environment. Depressive symptoms at baseline and at 12-week follow up were assessed using the nine-item Patient Health Questionnaire (PHQ-9). Patients in neighborhoods with high social affluence, high residential stability, and high neighborhood advantage were much less likely to have a persistent pattern of depressive symptoms compared to a pattern of few or no depressive symptoms (adjusted odds ratio (OR) = 0.06, 95 % confidence interval (CI) [0.01, 0.36]). Detrimental neighborhood influences may amplify risk for persistent depressive symptoms. [ABSTRACT FROM AUTHOR]

An understanding of past hydroclimatic variability is critical to resolving the significance of recent recorded trends in Australian precipitation and informing climate models. Our aim was to reconstruct past hydroclimatic variability in semi-arid northwest Australia to provide a longer context within which to examine a recent period of unusually high summer-autumn precipitation. We developed a 210-year ring-width chronology from Callitris columellaris, which was highly correlated with summer-autumn (Dec–May) precipitation (r = 0.81; 1910–2011; p < 0.0001) and autumn (Mar–May) self-calibrating Palmer drought severity index (scPDSI, r = 0.73; 1910–2011; p < 0.0001) across semi-arid northwest Australia. A linear regression model was used to reconstruct precipitation and explained 66% of the variance in observed summer-autumn precipitation. Our reconstruction reveals inter-annual to multi-decadal scale variation in hydroclimate of the region during the last 210 years, typically showing periods of below average precipitation extending from one to three decades and periods of above average precipitation, which were often less than a decade. Our results demonstrate that the last two decades (1995–2012) have been unusually wet (average summer-autumn precipitation of 310 mm) compared to the previous two centuries (average summer-autumn precipitation of 229 mm), coinciding with both an anomalously high frequency and intensity of tropical cyclones in northwest Australia and the dominance of the positive phase of the Southern Annular Mode. [ABSTRACT FROM AUTHOR]

Abstract: Objective: The purpose of this paper was to carefully examine the temporal relationships between anxiety disorders and urinary incontinence among community-dwelling adults. Method: In all, 1071 persons aged 30 and over were the continuing participants in a population-based longitudinal study of community-dwelling adults. Participants were classified as incontinent if any uncontrolled urine loss within the 12 months prior to the interview was reported. Condition-specific functional loss secondary to urinary incontinence was further assessed based on a series of questions relating directly to participants’ inability to engage in certain activities due to their urinary incontinence. Anxiety disorders were assessed with standardized interviews keyed to the diagnostic criteria. Results: In multivariate models that controlled for potentially influential characteristics the association between urinary incontinence with condition-specific functional loss and newly-incident anxiety disorders was statistically significant (adjusted relative odds (RO)=2.55, 95% confidence interval (CI) [1.05, 6.20]). Conclusions: Urinary incontinence with condition-specific functional loss predicted onset of newly-incident anxiety disorders among community-dwelling adults. [Copyright &y& Elsevier]

The aim of this study was to determine how spatial variation in vegetation type and landscape connectivity influence fire intervals in a semi-arid landscape with low relief and complex mosaics of woodland and shrubland vegetation. Our study focused on a 15,500-km area of relatively undisturbed and unmanaged land in south-western Australia, referred to as the Lake Johnston region. We modelled fire-interval data from a 67-year (1940-2006) digital fire history database using a two-parameter Weibull function, and tested for the effects of vegetation type and landscape connectivity on estimates of the length of fire intervals (Weibull parameter b) and the dependence of fire intervals on fuel age (Weibull parameter c). Vegetation type and landscape connectivity significantly influenced fire interval probability distributions. Fire intervals in shrublands (dense low shrub assemblage) were typically shorter ( b = 46 years) and more dependent on fuel age ( c = 2.33) than most other vegetation types, while fire intervals in open eucalypt woodlands were much longer ( b = 405 years) and were less dependent on fuel age ( c = 1.36) than in shrub-dominated vegetation types. Areas adjacent to or surrounded by salt lakes burnt less frequently ( b = 319 years) and fire intervals were less dependent on fuel age ( c = 1.48) compared with more exposed areas (e.g. b < 101 years, c > 1.68). Fire intervals in thickets (dense tall shrub assemblage) were longer ( b = 101 years) than would be expected from fuel loads, most likely because they were protected from fire by surrounding fuel-limited woodlands. Fire intervals in south-western Australia are strongly influenced by spatial variation in vegetation (fuel structure) and landscape connectivity. The importance of fuel structure as a control of fire intervals in south-western Australia contrasts with other landscapes, where topographical gradients or climatic influences may override the effects of underlying vegetation. We found that, regardless of low relief, topographical features such as large salt lake systems limited the connectivity and spread of fire among landscape units in an analogous manner to lakes or mountainous features elsewhere. [ABSTRACT FROM AUTHOR]

In early 2021 several tree stumps embedded in a remnant peat deposit were found in the intertidal zone of Wharton Beach, southwestern Australia by Esperance Tjaltjraak Rangers. Attempts were made to identify the tree using both dendrochronological and anthracological methods but were limited by the lack of reference information from tree species in the southwestern Australia. Radiocarbon dates from one stump indicates the tree lived for approximately 200 years, growing into the peaty sediments sometime before ca. 7340 cal yrs BP and died directly or indirectly as a result of marine transgression. The peat deposit is dated to 7608–7429 cal yrs BP but its exposed seaward edge was unconformably underlain by younger sand, dated by OSL to around 3550 years, which may have intruded as a result of a storm event. An OSL age of 12,600 years was obtained from the base of a laminated dune sequence behind the exposed peat deposit, and is significant given a similar age for a previously documented infant burial site in the area. Together these records provide a rare insight into the former wetland landscape and a cultural and scientific link to the drowned coastal plain. A need for more integrative research along this cultural corridor is clear but this preliminary study has demonstrated the value of combining Cultural Knowledge Systems and Western Science, for Tjaltjraak Healthy Country Program and analogous Aboriginal 'caring for country' programmes throughout Australia. [ABSTRACT FROM AUTHOR]

Australia's Great Western Woodlands are the largest intact temperate woodland ecosystem on Earth, spanning an area the size of the average European country. These woodlands are part of one of the world's biodiversity hotspots and, despite subsisting on just 200–400 mm of rainfall a year, can store considerable amounts of carbon. However, they face growing pressure from a combination of climate change and increasingly frequent and large wildfires, which have burned over a third of these slow-growing, fire-sensitive woodlands in last 50 years alone. To develop conservation strategies that bolster the long-term resilience of this unique ecosystem, we urgently need to understand how much old-growth woodland habitat remains intact and where it is distributed across this vast region. To tackle this challenge, we brought together data from an extensive network of field plots distributed across the region and combined this with information on vegetation 3D structure derived from drone, airborne and spaceborne LiDAR. Using this unique dataset, we developed a novel modelling framework to generate the first high-resolution maps of woodland tree size and age structure across the entire region. We found that 41.2% of the woodland habitat is covered by old-growth stands, equivalent to an area of approximately 39,187 km2. Only 10% of these old-growth woodlands fall within current protected areas managed by the state government. Instead, most remaining old-growth woodlands are found either within the Ngadju Indigenous Protected Area (26.9%) or outside of formal protected areas on leaseholds and privately owned lands (57.2%). Our maps of woodland size and age structure will help guide the targeted management and conservation of the Great Western Woodlands. Moreover, by developing a robust pipeline for integrating LiDAR data from multiple platforms, our study paves the way for mapping the 3D structure and carbon storage of open and heterogeneous woodland ecosystems from space. • Novel framework fusing drone, airborne and satellite LiDAR for large-scale mapping. • Fires have burned 39% of the world's largest temperate woodland in just 50 years. • Old-growth woodlands still cover 41% the region, equivalent to 38,715 km2. • Only 10% of old-growth woodlands are in protected areas managed by the government. [ABSTRACT FROM AUTHOR]

The author discusses data visualization in health care, which was started by nurse Florence Nightingale in the 1800s. Topics include Nightingale's efforts to examine the causes of hospital mortality during the Crimean War, her work to enhance cleanliness, hygiene, and equipment organization, her commitment to hospital and public health reform, as well as her use of data visualization to improve sanitary conditions in military hospitals.

Droughts are a recurrent and natural part of the Australian hydroclimate, with evidence of drought dating back thousands of years. However, our ability to monitor, attribute, forecast and manage drought is exposed as insufficient whenever a drought occurs. This paper summarises what is known about drought hazard, as opposed to the impacts of drought, in Australia and finds that, unlike other hydroclimatic hazards, we currently have very limited ability to tell when a drought will begin or end. Understanding, defining, monitoring, forecasting and managing drought is also complex due to the variety of temporal and spatial scales at which drought occurs and the diverse direct and indirect causes and consequences of drought. We argue that to improve understanding and management of drought, three key research challenges should be targeted: (1) defining and monitoring drought characteristics (i.e. frequency, start, duration, magnitude, and spatial extent) to remove confusion between drought causes, impacts and risks and better distinguish between drought, aridity, and water scarcity due to over-extractions; (2) documenting historical (instrumental and pre-instrumental) variation in drought to better understand baseline drought characteristics, enable more rigorous identification and attribution of drought events or trends, inform/evaluate hydrological and climate modelling activities and give insights into possible future drought scenarios; (3) improving the prediction and projection of drought characteristics with seasonal to multidecadal lead times and including more realistic modelling of the multiple factors that cause (or contribute to) drought so that the impacts of natural variability and anthropogenic climate change are accounted for and the reliability of long-term drought projections increases. [ABSTRACT FROM AUTHOR]

The effects of climate change are difficult to predict for many marine species because little is known of their response to climate variations in the past. However, long-term chronologies of growth, a variable that integrates multiple physical and biological factors, are now available for several marine taxa. These allow us to search for climate-driven synchrony in growth across multiple taxa and ecosystems, identifying the key processes driving biological responses at very large spatial scales. We hypothesized that in northwest (NW) Australia, a region that is predicted to be strongly influenced by climate change, the El Ni~no Southern Oscillation (ENSO) phenomenon would be an important factor influencing the growth patterns of organisms in both marine and terrestrial environments. To test this idea, we analyzed existing growth chronologies of the marine fish Lutjanus argentimaculatus, the coral Porites spp. and the tree Callitris columellaris and developed a new chronology for another marine fish, Lethrinus nebulosus. Principal components analysis and linear model selection showed evidence of ENSO-driven synchrony in growth among all four taxa at interannual time scales, the first such result for the Southern Hemisphere. Rainfall, sea surface temperatures, and sea surface salinities, which are linked to the ENSO system, influenced the annual growth of fishes, trees, and corals. All four taxa had negative relationships with the Ni~no-4 index (a measure of ENSO status), with positive growth patterns occurring during strong La Ni~na years. This finding implies that future changes in the strength and frequency of ENSO events are likely to have major consequences for both marine and terrestrial taxa. Strong similarities in the growth patterns of fish and trees offer the possibility of using tree-ring chronologies, which span longer time periods than those of fish, to aid understanding of both historical and future responses of fish populations to climate variation. [ABSTRACT FROM AUTHOR]