810 resultados para CLIMATES


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Objectively assessing ecological benefits of competing watering strategies is difficult. We present a framework of coupled models to compare scenarios, using the Coorong, the estuary for the MurrayDarling River system in South Australia, as a case study. The framework links outputs from recent modelling of the effects of climate change on water availability across the MurrayDarling Basin to a hydrodynamic model for the Coorong, and then an ecosystem-response model. The approach has significant advantages, including the following: (1) evaluating management actions is straightforward because of relatively tight coupling between impacts on hydrology and ecology; (2) scenarios of 111 years reveal the impacts of realistic climatic and flow variability on Coorong ecology; and (3) ecological impact is represented in the model by a series of ecosystem states, integrating across many organisms, not just iconic species. We applied the approach to four flow scenarios, comparing conditions without development, current water-use levels, and two predicted future climate scenarios. Simulation produced a range of hydrodynamic conditions and consequent distributions of ecosystem states, allowing managers to compare scenarios. This approach could be used with many climates and/or management actions for optimisation of flow delivery to environmental assets.

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An Australian research facility, MABEL (the Mobile Architecture and Built Environment Laboratory) measured several school classrooms for their indoor environmental performance (IEQ) performance. This paper is a reporting of a case study, highlighting the processed measurement of a classroom and its findings. A review of the literature, also reveals particular sectors of IEQ in schools that are worthy of measurement. A primary intention here is to determine the type of IEQ measurements and their evaluation methods together with their corresponding instrumentation. A secondary intention is to highlight particular IEQ discrepancies in existing school classroom design resulting from these case study measurements, suggesting construction and operational conditioning improvements.In particular this research reveals international research on the subject of IEQ in school buildings and confirms the usefulness, urgency and necessity of IEQ measurements, world wide, in this area. As most of the existing literature on the subject seems to fall short of acknowledging all sectors of IEQ, this paper would like to address the importance of multiple IEQ parameters, experienced through on-site measurement case studies. It is suggested that the existing literature intends to target a specific IEQ sector or parameter, predetermining its effect on student absenteeism or reduced performance. In contrast to this, this paper would like to acknowledge the interactive effects of an IEQ index (standard) in general. One of the reasons for this are that such an index still appears to remain in the developmental stages.Various sectors of IEQ measurements, as measured with the MABEL facility, are demonstrated in this paper. They illustrate a cross-section of typical classroom evidence-based problems backed by measurement. A literature review confirms that similar problems in school buildings are evident in other parts of Australia as well as throughout the world, in identical and different climates. A holistic IEQ measurement acknowledges that there may be several outstanding, as well as poor IEQ parameters within the same classroom. Solutions to these poor IEQ results may be remedied, yet, it is the measurement that highlights the periods, degree and extent to which these problems occur. It is suggested here that a holistic approach to IEQ is required and that the development of its measurement standards and reporting are desperately needed.

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The significance of physical education (PE) and sport in a boys’ school has long been highlighted as a device for the privileging of hyper-masculine identities (tough, stoic & assertive) at the expense of marginalised masculinities and femininities. The propensity for some “members of male sporting clique’s to engage in practices of bullying, shaming, violating and excluding” (Hickey, 2008, p. 148) raises important questions about how the practice of boys’ PE and sport can sometimes lead to unhealthy and damaging social interactions between different types of boys. In response to this rhetoric, some boys’ schools have acted to employ female PE teachers to disrupt “concern about the codes of unity, entitlement and privilege that can be forged among groups of boys whose identities are strongly aligned with sporting forms of hyper-masculinity” (Hickey, 2008, p. 148). Given this potential, we suggest that there is something unique or different about working in spaces or contexts around boys’ physicality. More specifically this paper raises questions about the particular implications for a PE teacher’s professional work, particularly as a female PE teacher.

In current educational climates the performance of boys in social and educational contexts attracts considerable concern. Better understanding the contributions and capacities of female PE teachers in all boys’ schools, (as localised social and political environments in which gendered identities are formed) is warranted. Professional identities and “the meaning of gender is negotiated in everyday interactions” (Priola, 2007, p. 23) implicating the culture of all boys’ schools as significant in the development of ideas around effective, gender inclusive, pedagogical practices. Drawing on case study data, this paper seeks to explore how notions of effectiveness about boys’ PE are formed, with intent to make visible the extent to which female PE teachers influence dominant gendered practices of social interaction in all boys’ PE settings.

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Purpose - This study aimed to identify the nature and prevalence of workplace stressors faced by interviewers of child sexual assault victims.

Design/methodology/approach - Sixty-eight professionals (police and child protection workers) were invited to anonymously post their perceptions of workplace stressors on an internet forum as part of an investigative interviewing online training course. Specifically, participants were asked to reflect on salient sources of stress encountered in their role of interviewing sexually abused children.

Findings - Three key stressors were identified across the study’s professional groups: (1) inadequate recognition of specialised skills; (2) high workload demands; and (3) interagency tensions. Consistent with previous research, exposure to child abuse reports was not raised as a stressor.

Research limitations/implications - Our study generated suggestions for modifying management practices; however, future research should identify and trial strategies for improving workplace climate in child abuse investigation.

Practical implications - As the stressors isolated by participants related to workplace climate rather than exposure to victims’ accounts of child abuse, minimising negative consequences of work stressors requires changes to workplace culture and practice. Workplace climates need to be modified so that the demands are offset by resources.

Originality/value - Because of its online, anonymous nature, this was the first study to offer participants the opportunity to honestly disclose primary sources of stress in child abuse investigation. The research also makes a much-needed contribution to an area of police practice that is vital yet often overlooked.

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If heat generated through activity can substitute for heat required for thermoregulation, then activity in cold environments may be energetically free for endotherms. Although the possibility of activity-thermoregulatory heat substitution has been long recognized, its empirical generality and ecological implications remain unclear. We combine a review of the literature and a model of heat exchange to explore the generality of activity-thermoregulatory heat substitution, to assess the extent to which substitution is likely to vary with body size and ambient temperature, and to examine some potential macroecological implications. A majority of the 51 studies we located showed evidence of activity-thermoregulatory heat substitution (35 of 51 studies), with 28 of 32 species examined characterized by substitution in one or more study. Among studies that did detect substitution, the average magnitude of substitution was 57%, but its occurrence and extent varied taxonomically, allometrically, and with ambient temperature. Modeling of heat production and dissipation suggests that large birds and mammals, engaged in intense activity and exposed to relatively warm conditions, have more scope for substitution than do smaller endotherms engaged in less intense activity and experiencing cooler conditions. However, ambient temperature has to be less than the lower critical temperature (the lower bound of the thermal neutral zone) for activity-thermoregulatory heat substitution to occur and this threshold is lower in large endotherms than in small endotherms. Thus, in nature, substitution is most likely to be observed in intermediate-sized birds and mammals experiencing intermediate ambient temperatures. Activity-thermoregulatory heat substitution may be an important determinant of the activity patterns and metabolic ecology of endotherms. For example, a pattern of widely varying field metabolic rates (FMR) at low latitudes that converges to higher and less variable FMR at high latitudes has been interpreted as suggesting that warm environments at low latitudes allow a greater variety of feasible metabolic niches than do cool, high-latitude environments. However, activity-thermoregulatory heat substitution will generate this pattern of latitudinal FMR variation even if endotherms from cold and warm climates are metabolically and behaviorally identical, because the metabolic rates of resting and active animals are more similar in cold than in warm environments. Activity-thermoregulatory heat substitution is an understudied aspect of endotherm thermal biology that is apt to be a major influence on the physiological, behavioral and ecological responses of free-ranging endotherms to variation in temperature.

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Travellers undertake a process of reorientation and realignment that is particular to each destination. This process intensifies when travelling long distances across borders, cultures and climates, as travellers utilise performative, embodied and creative methods that respond to each new environment. Certain destinations, such as those with unique and extreme natural environments, induce a socio-cultural imaginary that primes travellers for what kind of experience they might have. Large, immersive landscapes and climates congeal with expectations of what each destination requires in order to navigate through it. Common bearings of distance and scale are skewed, as travellers are positioned within areas of vastness. In these moments immersive experiences contrast with daily processes, such as the act of packing a bag, as this heightened sensory awareness exacerbates the subtle material and spatial negotiations. Utilising interviews and photographic documentation of travellers to Iceland and Nepal, this paper develops the proposal that certain destinations intensify our attunement to these moments of reorientation, facilitating situated and creative methods.

As recent developments in the fields of mobilities and tourism draws attention to material interactions during travel, and current ‘new materialism’ movements in theory and practice reveal alternative affective methods of engagement, an exploration of interactions with/in immersive sites is needed in order to evaluate the potential that these kinds of transitions offer everyday experiences of movement. Nigel Thrift’s proposition of Non-Representational Theory provides clarity on the ways in which spatial awareness influences such transitions and environmental experiences. Using his acknowledgement of a more ontologically driven responsiveness to space, this permits a shift away from the presupposed containment of spaces as isolated destinations, toward a relational spatiality that encompasses all actors – including environments – as vital elements in the generative processes of situating our movements.

Creative strategies that afford sensory, aesthetic and embodied performances provide ways to examine these experiences, providing a multitude of possibilities as individual experiences shift towards collective and collaborative performances, as we are immersed within a range of human and non-human actors. This paper explores the transition away from ‘consuming’ environments, and advocates for the need to turn towards a situated collaboration with environments, propelling an awareness of sustainable and creative travel practices. An understanding of affirmative differences is required within travel cultures, rather than expressing transitions as confined within the ‘home’ versus ‘away’ dichotomy that lingers from elite western travel narratives. In order to undertake the many movements required, this paper draws on the theoretical approaches of sustainable nomadism as described by Rosi Braidotti to highlight the linkages of environmental and bodily experiences.

Through multidisciplinary literature, interviews and personal reflections, this paper proposes that certain destinations amplify processes of alignment with the environment, developing affective, embodied and situated experiences that overcome the human/non-human divide.

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Energy crisis is one of the major obstacles for human development. There are on-going researches to overcome this for a sustainable environment and economy. Passive air cooling system of earth pipe cooling is seen as a viable energy efficient technology for hot and humid subtropical climates. It can be an attractive economical alternative to conventional cooling since there are no compressors or any habitual mechanical unit. It utilizes earth’s near constant underground temperature to cool air for residential, agricultural or industrial uses. This paper reports the thermal performance of earth pipe cooling technology for a hot and humid subtropical climatic zone in Queensland, Australia. A series of pipes buried underground were used in order to increase the cooling performance of the system. To measure the thermal performance, a thermal model was developed for the earth pipe cooling system and simulated using ANSYS Fluent. Data were collected from two modelled rooms built from shipping containers and installed at Central Queensland University, Rockhampton, Australia. The impact of air temperature and velocity on room cooling performance has also been assessed. A significant temperature reduction is seen in this study, which will save energy cost for thermal cooling in buildings.

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Many temperate estuaries have intermittently open and closed mouths, a feature that is often related to intermittent freshwater input. These systems, often overlooked due to their small size, can have large hydrological variability over medium-term time scales.

This variability presents potential difficulties for estuarine species particularly where anthropogenic alterations to freshwater flows can cause large deviations from natural patterns of tidal influence and inundation of habitat.

Influences of natural and hydrological variability on seagrasses were examined in two central Victorian estuaries with anthropogenically-modified but naturally-intermittent freshwater flows and mouth openings. Comparisons were focused on differences between an estuary with artificially-augmented freshwater inflow and an adjacent system, in which the volume and timing of inflows were altered by a reservoir. Eight additional estuaries in the region were also used to provide a context for these two main sites.

Hydrological changes during the three-year field component were affected by the ending of a drought and then a major flood a year later as well as by ongoing anthropogenic flow reduction and augmentation. These influences on hydrology were associated with an initially high seagrass coverage that was substantially reduced and showed signs of recovery only in the system that was affected by lower inflows. Such influences and responses also changed seasonally but to a much lesser extent than the responses to stochastic climatic events.

Natural flows were intermittent and varied substantially between years. Flooding flows represented up to 89% of the long-term annual average flow. Water quality was broadly typical of the region, with the exception of low pH in some tributaries, especially those of Anglesea estuary. Anthropogenic changes to flow were most evident at times of low natural flows and resulted in longer and more frequent periods of zero inflow to Painkalac estuary and a continual base flow to Anglesea. This base flow, from ponds containing coal ash, neutralised waters flowing from upstream and increased conductivity, except at times of high natural flow.

A three-state conceptual model of the magnitude and variability of water levels, based largely on the degree of tidal influence was identified and quantitatively assessed for the two estuaries that were the main focus of the study. These states in turn had a large influence on the area and inundation of benthic habitat. Floods tended to open the mouths of estuaries, which then remained tidal given sufficient flow to overcome sedimentary processes at the mouths. Low and zero inflow was a precondition for closure of the mouths of the estuaries. When closed, differences in inflow resulted in different endpoints in salinity patterns. From an initial pattern similar to a classic ‘salt wedge’, Painkalac estuary, with reduced inflow, quickly destratified and gradually became more saline, at times hypersaline. Anglesea estuary, with augmented flow, tended to remain stratified for longer until becoming completely fresh, given a long enough period of closure.

Episodic changes in the water quality of the estuaries were associated with different components of the freshwater flow regimes. At high flows, fresh waters of low pH with a high metal load entered Anglesea estuary. Except during the largest flood, when the estuary was completely flushed, this water was neutralised at the halocline and resulting in precipitation of metals. High flows into Painkalac were associated with elevated concentrations of clay-sourced suspended solids. During a closed period, with zero flow, a release of sediment-bound nutrients triggered by anoxia was observed in Painkalac, followed by an algal bloom.

The large decline in seagrass extent that was observed in both estuaries was closely related to floods and the subsequent reductions in potential habitat associated with the tidal states that followed. Analysis of historical patterns of extent against rainfall records suggested that periods of drought and extended mouth closures were related to establishment and expansion of beds. This model was similar to that described for South African estuaries and contrasted with more-seasonal patterns reported for local marine embayments.

Rates of in situ decomposition of seagrass detritus showed a mix of seasonal and disturbance-driven patterns of change, depending on estuary. Variability of these rates on a scale of 100s of metres was typically not significant, but there were a few episodes that were highly significant. A negative correlation between decomposition rate and seagrass extent was also observed. A novel technique for assessing cellulose decomposition potential in sediment, adapted from soil science, proved to be a useful tool for estuarine research. Results from this component of the study highlighted both small-scale variability that was inconsistent through time, and also stable differences in decomposition potential between depths and estuaries that were consistent with differences in hydrological state and salinity.

Given the relative lack of knowledge about processes in intermittent estuaries, particularly those relating to changes in freshwater inflow, results from this study will be of value both locally and for similar systems elsewhere. Locally, it is likely that flow regimes to both Anglesea and Painkalac estuaries will be reduced, following closure of the mine power station at Anglesea and due to increased demand from the reservoir above Painkalac. There is potential to manage flows from each of these sources to minimise downstream effects. Regionally, and globally, there are many intermittent estuaries in areas with Mediterranean-type climates. It has been predicted that the climates of these regions will become drier but with an increase in intensity of storm events, both of which have ramifications for flow regimes to estuaries. It is hoped that results of this study will contribute to more informed management of intermittent estuaries in the context of these likely changes.

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 Putrajaya is a model city planned with concepts of a "city in the garden" and an "intelligent city" in the tropics. This study presents the behaviour of the surface temperature and the heat island effect of Putrajaya. Findings show that heat island intensity is 2 °C on average at nighttime and negligible at daytime. But high surface temperature values were recorded at the main boulevard due to direct solar radiation incident, street orientation in the direction of northeast and southwest and low building height-to-street width ratio. Buildings facing each other had cooling effect on surfaces during the morning and evening hours; conversely, they had a warming effect at noon. Clustered trees along the street are effective in reducing the surface temperature compared to scattered and isolated trees. Surface temperature of built up areas was highest at noon, while walls and sidewalks facing northwest were hottest later in the day. Walls and sidewalks that face northwest were warmer than those that face southeast. The surface temperatures of the horizontal street surfaces and of vertical façades are at acceptable levels relative to the surface temperature of similar surfaces in mature cities in subtropical, temperate and Mediterranean climates. © 2014 Springer-Verlag Wien.

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Reforestation has large potential for mitigating climate change through carbon sequestration. Native mixed-species plantings have a higher potential to reverse biodiversity loss than do plantations of production species, but there are few data on their capacity to store carbon. A chronosequence (5-45 years) of 36 native mixed-species plantings, paired with adjacent pastures, was measured to investigate changes to stocks among C pools following reforestation of agricultural land in the medium rainfall zone (400-800 mm yr(-1) ) of temperate Australia. These mixed-species plantings accumulated 3.09 ± 0.85 t C ha(-1)  yr(-1) in aboveground biomass and 0.18 ± 0.05 t C ha(-1)  yr(-1) in plant litter, reaching amounts comparable to those measured in remnant woodlands by 20 years and 36 years after reforestation respectively. Soil C was slower to increase, with increases seen only after 45 years, at which time stocks had not reached the amounts found in remnant woodlands. The amount of trees (tree density and basal area) was positively associated with the accumulation of carbon in aboveground biomass and litter. In contrast, changes to soil C were most strongly related to the productivity of the location (a forest productivity index and soil N content in the adjacent pasture). At 30 years, native mixed-species plantings had increased the stability of soil C stocks, with higher amounts of recalcitrant C and higher C : N ratios than their adjacent pastures. Reforestation with native mixed-species plantings did not significantly change the availability of macronutrients (N, K, Ca, Mg, P, and S) or micronutrients (Fe, B, Mn, Zn, and Cu), content of plant toxins (Al, Si), acidity, or salinity (Na, electrical conductivity) in the soil. In this medium rainfall area, native mixed-species plantings provided comparable rates of C sequestration to local production species, with the probable additional benefit of providing better quality habitat for native biota. These results demonstrate that reforestation using native mixed-species plantings is an effective alternative for carbon sequestration to standard monocultures of production species in medium rainfall areas of temperate continental climates, where they can effectively store C, convert C into stable pools and provide greater benefits for biodiversity.

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BACKGROUND: Despite the growing awareness of the benefits of positive workplace climates, unsupportive and disruptive workplace behaviours are widespread in health care organisations. Recent graduate nurses, who are often new to a workplace, are particularly vulnerable in unsupportive climates, and are also recognised to be at higher risk for medication errors. OBJECTIVES: Investigate the association between workplace supports and relationships and safe medication practice among graduate nurses. DESIGN AND PARTICIPANTS: Exploratory study using quantitative survey with a convenience sample of 58 nursing graduates in two Australian States. METHODS: Online survey focused on graduates' self-reported medication errors, safe medication practice and the nature of workplace supports and relationships. RESULTS: Spearman's correlations identified that unsupportive workplace relationships were inversely related to graduate nurse medication errors and erosion of safe medication practices, while supportive Nurse Unit Manager and supportive work team relationships positively influenced safe medication practice among graduates. CONCLUSIONS: Workplace supports and relationships are potentially both the cause and solution to graduate nurse medication errors and safe medication practices. The findings develop further understanding about the impact of unsupportive and disruptive behaviours on patient safety and draw attention to the importance of undergraduate and continuing education strategies that promote positive workplace behaviours and graduate resilience.

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Students look forward to summer because usually it means a break from formal and non-formal education. Formal education refers to education in formal educational institutions, such as pre-schools, primary, secondary and tertiary educational institutions and other registered training organisations. Non-formal education refers to organised educational activity outside the established formal system, that is intended to deliver a defined set of learning objectives to an identifiable group of learners (Chemistry in Australia, October 2014, page 33). Informal education refers to all learning outside the formal non-formal educational system; informal education is often associated with life-long learning as it can include reading non-fiction books and scholarly articles, viewing documentaries and other informal professional development. Informal education can also include travel to other countries and climates. Social constructivist theory maintains that learning occurs in social settings; conversely, most learners are limited by their cultural experiences. For example, Australian students have little first-hand experience of sublimation, but this is commonly observed in very cold climates when frost, ice or snow apparently “disappears” as it sublimes to water vapour, without passing through the liquid state. A favourite summertime activity is to go to the movies, especially in air-conditioned cinemas on a hot day or night. Watching movies are a form of virtual travel, and many educators make use of movies to illustrate chemistry concepts. Some movie producers want a sense of authenticity and work hard to get the details right, even though those details might be incidental to the main plot. For example, in Centurion, Roman soldiers fail in their rescue attempt, and are taunted by the Picts for stupidity -- they would have succeeded if they had only realised that metal become brittle in the cold. Another favourite example comes from The Lord of the Rings: The Two Towers, when Bilbo, Samwise and Gollum are crossing the Dead Marshes and see lights that appear to float over the Marshes. These wills-o-the-wisp have been known for centuries, and was the subject of a debate between George Washington and his officers. Washington and Thomas Paine, “the Father of the American Revolution”, believed that the lights were due to a flammable gas released from the marsh, while Washington’s officers believed that the lights were due to a flammable liquid on the surface of the marsh. On Guy Fawkes Night, 5 November, 1783, the Washington-Paine experiment showed that when mud at the bottom of a river was disturbed, bubbles of flammable gas rose to the surface of the water. (Unknown to Washington and Paine, Alessandro Volta had performed a similar experiment in 1776.) A problem with informal education is that it is often unguided. Students may find it difficult to discern the difference between scientific reality and an artistic distortion of reality in novels and movies. Educators have an important role here. If we only teach facts and concepts, learners will be dependent on a teacher. If however, we foster students’ curiosity and ability to exercise judgement, they will be able to learn for themselves, not just during the summer, but also in every season of every year.

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Management strategies to reduce the risks to human life and property from wildfire commonly involve burning native vegetation. However, planned burning can conflict with other societal objectives such as human health and biodiversity conservation. These conflicts are likely to intensify as fire regimes change under future climates and as growing human populations encroach farther into fire-prone ecosystems. Decisions about managing fire risks are therefore complex and warrant more sophisticated approaches than are typically used. We applied a multicriteria decision making approach (MCDA) with the potential to improve fire management outcomes to the case of a highly populated, biodiverse, and flammable wildland-urban interface. We considered the effects of 22 planned burning options on 8 objectives: house protection, maximizing water quality, minimizing carbon emissions and impacts on human health, and minimizing declines of 5 distinct species types. The MCDA identified a small number of management options (burning forest adjacent to houses) that performed well for most objectives, but not for one species type (arboreal mammal) or for water quality. Although MCDA made the conflict between objectives explicit, resolution of the problem depended on the weighting assigned to each objective. Additive weighting of criteria traded off the arboreal mammal and water quality objectives for other objectives. Multiplicative weighting identified scenarios that avoided poor outcomes for any objective, which is important for avoiding potentially irreversible biodiversity losses. To distinguish reliably among management options, future work should focus on reducing uncertainty in outcomes across a range of objectives. Considering management actions that have more predictable outcomes than landscape fuel management will be important. We found that, where data were adequate, an MCDA can support decision making in the complex and often conflicted area of fire management.

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Aim: Allen's rule posits that the appendages of endothermic organisms will be larger in warmer climates to allow for dumping of heat loads. Given a link between appendage size and climate, we tested the prediction that climate change has driven the evolution of larger bills in birds, resulting in measurable changes over the recent past. Location: Australia. Methods: We explored geographical and temporal variation in bill surface area of five Australian parrot species to determine whether individuals from warmer climates have larger bills, and whether there have been increases in bill surface area over time, consistent with climatic warming. Measurements were obtained from museum specimens dating from 1871 to 2008. These data were then related to geographical location, collection date and locality-specific climate data, in order to construct and compare models of spatio-temporal and climate-related variation in bill morphology. Results: There have been increases in bill surface area in mulga parrots (Psephotus varius), gang-gang cockatoos (Callocephalon fimbriatum), red-rumped parrots (Psephotus haematonotus) and male crimson rosellas (Platycercus elegans), equating to a c. 4-10% increase in bill surface area since 1871. Average maximum summer temperature in the 5 years prior to specimen collection also positively predicted bill surface area in mulga parrots, red-rumped parrots and crimson rosellas, consistent with Allen's rule. With the exception of red-rumped parrots, however, models with geographical location and year of collection were still better predictors of bill surface area than local climate at the date of collection. Main conclusions: Our analysis provides evidence that four species of parrot have exhibited adaptive change in bills over the past century potentially mitigating the thermal stress caused by climatic warming. Although consistent with the predicted effects of climate change, the temporal patterns we observe may have additional causes, however, such as changes in primary productivity, habitat or food availability.