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In this paper we assess the impact of climate change, at a micro-scale for a selection of four sites in New Zealand and Australia. These sites are representative of the key destination ski regions. In contrast to previous work, our work will for the first time, allow for a direct comparison between these two countries and enable both an estimate of the absolute impacts at a given site, as well as the relative impacts between the two countries. This direct comparison is possible because we have used exactly the same snow model, the same 3 global climate models (GCMs) and the same techniques to calibrate the model for all locations. We consider the changes in natural snow at these locations for the 2030-2049 and 2080-2099 time periods, for one mid-range emissions scenario (A1B). This future scenario is compared to simulations of current, 1980-1999, snow at these locations. We did not consider the snowmaking or economic components of the ski industry vulnerability, only the modelled changes in the natural snow component. At our New Zealand sites, our model indicates that by the 2040s there will be on average between 90 % and 102 % of the current maximum snow depth (on 31 August) and by the 2090s this will be on average reduced to between 46 % and 74 %. In Australia, our models estimates that by the 2040s there will be on average between 57 % and 78 % of the current maximum snow depth and by the 2090s this will be on average further reduced to between 21 % and 29 %. In terms of days with snowdepths equal to or exceeding a ski industry useable levels of 0.30 m, at our lowest elevation, and most sensitive sites, we observe a change from 125 days (current) to 99-126 (2040s) and 52-110 (2090s) in New Zealand. In Australia, a reduction from 94 to 155 days (current) to 81-114 (2040s) and 0-75 (2090s) is observed. In each case the changes are highly depended on the GCM used to drive the climate change scenario. While the absolute changes will have direct impacts at each location, so too will the relative changes with respect to future potential Australia-New Zealand tourism flows, and beyond. Our study provides an approach by which other regions or countries with climate sensitive tourism enterprises could assess the relative impacts and therefore the potential wider ranging ramifications with respect to destination attractiveness. [ABSTRACT FROM AUTHOR]

Alpine plants in Australia are increasingly exposed to more frequent drought and heatwaves, with significant consequences for physiological stress responses. Acclimation is a critical feature that allows plants to improve tolerance to environmental extremes by directly altering their physiology or morphology. Yet it is unclear how plant performance, tolerance, and recovery are affected when heat and water stress co-occur, and whether prior exposure affects responses to subsequent climate extremes. We grew a common alpine grass species under high or low watering treatments for three weeks before exposure to either none, one, or two heat stress events. We determined photosynthetic heat and freezing tolerance (LT50, mean temperature causing 50% irreversible damage to photosystem II) and growth. Physiological adjustments to low watering, including more negative water potentials and reduced growth, were also characterised by improved tolerance to high and low-temperature extremes. Shifts to higher heat tolerance were also evident with increasing exposure to heat stress events, though freezing tolerance was not affected. Acclimation effects were mostly short-term, however; prior exposure to heat and/or water stress had little to no effect on growth and thermal tolerance following the six-week recovery period. We conclude that rapid acclimation to water and heat stress that co-occur during summer enhances the capacity of alpine plants to tolerate increasingly frequent temperature extremes. [ABSTRACT FROM AUTHOR]

Some recent funding programmes in Australia on climate adaptation have expected active engagement with farmers in research projects. Based on our direct experience with 30 farmers and their advisors, we list five reasons why it is difficult to gain traction with farmers in discussing the likely impacts of climate change on their farms and the possible adaptation options they should be considering in preparation for a future changed climate. The reasons concern the slow and uncertain trajectory for changes in climate relative to the time horizon for farm decision-making, when set against short-term fluctuations in weather, prices, costs and government policy. Farmers have optimism for ongoing technological progress keeping abreast of any negative impacts of climate on their production. As one moves from incremental to transformational adaptation options, biophysical research has less to offer because decisions become based more on business structure, portfolio management, off-farm investments and geographical diversification. Some farmers also doubt the intentions of climate change researchers and are wary of anything they may have to offer. We propose there is an actionable decision space where agricultural science and economics can contribute to meaningful analysis of impacts and adaptation to climate change by farmers. This will involve emphasising the principles of farm management rather than defining optimal farm plans; the use of scenario planning to explore possible futures in a turbulent environment for farming; a focus on short-term adjustments as a path to longer term adaptation; re-gaining the trust of some farmers towards climate change scientists through better communication strategies; and understanding the linkages between adaptation options and enabling factors and technologies. [ABSTRACT FROM AUTHOR]

Australia, a country which has regularly experienced various natural disasters, is now set to face more intense and frequent disasters in the twenty-first century as a result of climate change. Prior research indicates that in Australia, the perceived risks of climate change are mixed and becoming less prevalent across rural and urban locations, posing a threat to the public's adoption of mitigation and adaptation strategies. Research was conducted in four disaster-impacted rural Australian towns to investigate whether prior disaster experience, trust in climate change risk communications and specific location predicted climate change risk perceptions. Four case study sites were chosen exemplifying communities impacted by different types of disaster events. The case study towns were Beechworth (wildfire, 2009) and Bendigo (drought, 2002-2008) in Victoria; Ingham (flood, 2009) and Innisfail (cyclone, 2006) in Queensland. Structural equation modelling analyses of surveys returned by a sample of 1,008 householders across the four towns showed that prior disaster experience had no impact upon climate change risk perceptions. Instead climate change risk perceptions were predicted by trust in climate change communications, climate change knowledge and the geographical location of the sample, suggesting the need for targeted, place-specific contextual communication interventions that consider the needs and socioeconomic characteristics of the community in question. [ABSTRACT FROM AUTHOR]

While many factors affecting human health that will alter with climate change are being discussed, there has been no discussion about how a warmer future will affect man's thermoregulation. Using historical climate data for an Australian city and projections for Australia's climate in 2070, we address the issue using heat balance modelling for humans engaged in various levels of activity from rest to manual labour. We first validate two heat balance models against empirical data and then use the models to predict the number of days at present and in 2070 that (1) sweating will be required to attain heat balance, (2) heat balance will not be possible and hyperthermia will develop, and (3) body temperature will increase by 2.5°C in less than 2 h, which we term 'dangerous days'. The modelling is applied to people in an unacclimatised and an acclimatised state. The modelling shows that, for unacclimatised people, outdoor activity will not be possible on 33-45 days per year, compared to 4-6 days per year at present. For acclimatised people the situation is less dire but leisure activity like golf will be not be possible on 5-14 days per year compared to 1 day in 5 years at present, and manual labour will be dangerous to perform on 15-26 days per year compared to 1 day per year at present. It is obvious that climate change will have important consequences for leisure, economic activity, and health in Australia. [ABSTRACT FROM AUTHOR]

Climate change is a major threat to coral reef ecosystems worldwide. A key determinant of the fate of reef corals in a warming climate is their capacity to tolerate increasing thermal stress. Here, an increase in thermal tolerance is demonstrated for three major coral genera ( Acropora, Pocillopora and Porites) following the extensive mass bleaching event that occurred on the Great Barrier Reef (Australia) in 1998. During the subsequent and more severe thermal stress event in 2002, bleaching severity was 30–100% lower than predicted from the relationship between severity and thermal stress in 1998, despite higher solar irradiances during the 2002 thermal event. Coral genera most susceptible to thermal stress ( Pocillopora and Acropora) showed the greatest increase in tolerance. Although bleaching was severe in 1998, whole-colony mortality was low at most study sites. Therefore, observed increases in thermal tolerance cannot be explained by selective mortality alone, suggesting a capacity for acclimatization or adaptation. Although the vulnerability of coral reefs remains largely dependent on the rate and extent of climate change, such increase in thermal tolerance may delay the onset of mass coral mortalities in time for the implementation of low-emission scenarios and effective management. [ABSTRACT FROM AUTHOR]

We explore the impact of future climate change on the risk of forest and grassland fires over Australia in January using a high resolution regional climate model, driven at the boundaries by data from a transitory coupled climate model. Two future emission scenarios (relatively high and relatively low) are used for 2050 and 2100 and four realizations for each time period and each emission scenario are run. Results show a consistent increase in regional-scale fire risk over Australia driven principally by warming and reductions in relative humidity in all simulations, under all emission scenarios and at all time periods. We calculate the probability density function for the fire risk for a single point in New South Wales and show that the probability of extreme fire risk increases by around 25% compared to the present day in 2050 under both relatively low and relatively high emissions, and that this increases by a further 20% under the relatively low emission scenario by 2100. The increase in the probability of extreme fire risk increases dramatically under the high emission scenario by 2100. Our results are broadly in-line with earlier analyses despite our use of a significantly different methodology and we therefore conclude that the likelihood of a significant increase in fire risk over Australia resulting from climate change is very high. While there is already substantial investment in fire-related management in Australia, our results indicate that this investment is likely to have to increase to maintain the present fire-related losses in Australia. [ABSTRACT FROM AUTHOR]