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East Melbourne, Australia

Fox-Hughes P.,University of Tasmania | Fox-Hughes P.,Bushfire Co operative Research Center
Journal of Applied Meteorology and Climatology | Year: 2011

Half-hourly airport weather observations have been used to construct high-temporal-resolution datasets of McArthur Mark V forest fire danger index (FFDI) values for three locations in Tasmania, Australia, enabling a more complete understanding of the range and diurnal variability of fire weather. Such an understanding is important for fire management and planning to account for the possibility of weather-related fire flare ups-in particular, early in a day and during rapidly changing situations. In addition, climate studies have hitherto generally been able to access only daily or at best 3-hourly weather data to generate fire-weather index values. Comparison of FFDI values calculated from frequent (subhourly) observations with those derived from 3-hourly synoptic observations suggests that large numbers of significant fire-weather events are missed, even by a synoptic observation schedule, and, in particular, by observations made at 1500 LT only, suggesting that many climate studies may underestimate the frequencies of occurrence of fire-weather events. At Hobart, in southeastern Tasmania, only one-half of diurnal FFDI peaks over a critical warning level occur at 1500 LT, with the remainder occurring across a broad range of times. The study reinforces a perception of pronounced differences in the character of fire weather across Tasmania, with differences in diurnal patterns of variability evident between locations, in addition to well-known differences in the ranges of peak values observed. © 2011 American Meteorological Society. Source

Kosmadopoulos A.,Central Queensland University | Kosmadopoulos A.,Bushfire Co operative Research Center | Sargent C.,Central Queensland University | Darwent D.,Central Queensland University | And 2 more authors.
Annales des Telecommunications/Annals of Telecommunications | Year: 2014

The objective of this study was to assess the validity of a sleep/wake activity monitor, an energy expenditure activity monitor, and a partial-polysomnography system at measuring sleep and wake under identical conditions. Secondary aims were to evaluate the sleep/wake thresholds for each activity monitor and to compare the three devices. To achieve these aims, two nights of sleep were recorded simultaneously with polysomnography (PSG), two activity monitors, and a partial-PSG system in a sleep laboratory. Agreement with PSG was evaluated epoch by epoch and with summary measures including total sleep time (TST) and wake after sleep onset (WASO). All of the devices had high agreement rates for identifying sleep and wake, but the partial-PSG system was the best, with an agreement of 91.6 % ± 5.1 %. At their best thresholds, the sleep/wake monitor (medium threshold, 87.7 % ± 7.6 %) and the energy expenditure monitor (very low threshold, 86.8 % ± 8.6 %) had similarly high rates of agreement. The summary measures were similar to those determined by PSG, but the partial-PSG system provided the most consistent estimates. Although the partial-PSG system was the most accurate device, both activity monitors were also valid for sleep estimation, provided that appropriate thresholds were selected. Each device has advantages, so the primary consideration for researchers will be to determine which best suits a given research design. © 2014, Psychonomic Society, Inc. Source

Kruger T.M.,University of Melbourne | Kruger T.M.,Bushfire Co operative Research Center | Beilin R.,University of Melbourne
International Journal of Wildland Fire | Year: 2014

This research considers ideas about local knowledge and place for firefighters during a bushfire. In 2012, we interviewed 68 Australian bushfire firefighters from selected agencies and volunteer brigades in diverse localities. The findings from the interviews indicate local knowledge can help firefighters to navigate tracks and understand fire behaviour in familiar landscapes. At the same time, they can experience a heightened awareness of the fire on local people and valued assets. This sets up a 'responsibility for place', which can both mediate actions during the fire and increase risk to the firefighters involved. A distant fire can present many unknowns and potential hazards for deployed firefighters because they do not have local knowledge. This disconnect can mean they are more cautious in negotiating unfamiliar surrounds and awaiting orders. We find that although local knowledge can assist firefighters, it highlights the complexity of decision-making during a fire that can make it more hazardous for local firefighters. This research contributes to firefighter training by exploring how local knowledge associated with landscape and community can dominate decision-making in practice. © IAWF 2014. Source

Penman T.D.,Forest and Rangeland Ecosystems | Penman T.D.,Bushfire Co operative Research Center | Binns D.L.,Forests NSW | Shiels R.J.,Forest and Rangeland Ecosystems | And 3 more authors.
Austral Ecology | Year: 2011

Forest management practices have the potential to impact upon native vegetation. Most studies focus on the effects of management on the above-ground vegetation communities, with little attention given to the soil stored seed bank. Here we examine the soil stored seed bank of a long-term experimental site in south-eastern Australia, which has experienced timber harvesting and repeated prescribed burning over a 20-year period. At each of 213 long-term vegetation measurement plots, 3.5kg of soil was collected and germinated in a glasshouse over a period of 2years. Comparisons were made between the experimental treatments considering differences in species richness, abundance and community composition of the understorey seed bank. Logged sites had a higher diversity and abundance of seedlings compared with unlogged sites, which is consistent with observed changes in standing vegetation within 10years following logging. Prescribed burning resulted in a lower diversity and abundance of seedlings, which contrasts with the increase in species diversity observed in response to frequent fire in standing vegetation. Individual taxa that declined in the seed bank in response to frequent fire were all taxa for which germination is enhanced by exposure to smoke. Contrary to expectations, these did not exhibit a corresponding decline as standing plants. While management actions above ground are having minor impacts, greater effects were seen in the soil stored seed bank. © 2010 The Authors. Journal compilation © 2010 Ecological Society of Australia. Source

Raines J.,Deakin University | Raines J.,Bushfire Co operative Research Center | Snow R.,Deakin University | Petersen A.,Deakin University | And 6 more authors.
Applied Ergonomics | Year: 2012

Wildfire fighters are known to report to work in a hypohydrated state, which may compromise their work performance and health. Purpose: To evaluate whether ingesting a bolus of fluid before the shift had any effect on firefighters' fluid consumption, core temperature, or the time they spent in high heart rate and work activity zones when fighting emergency wildfires. Methods: Thirty-two firefighters were divided into non-bolus (AD) and pre-shift drinking bolus (PS, 500ml water) groups. Results: Firefighters began work hypohydrated as indicated by urine colour, specific gravity and plasma osmolality (P osm) results. Post-shift, firefighters were classified as euhydrated according to P osm and hypohydrated by urinary markers. No significant differences existed between the drinking groups in pre- or post-shift hydration status, total fluid intake, activity, heart rate or core temperature. Conclusion: Consuming a bolus of fluid, pre-shift provided no benefit over non-consumption as both groups had consumed equivalent ad libitum volumes of fluid, 2.5h into the shift. No benefits of bolus consumption were observed in firefighter activity, heart rate response or core temperature response across the shift in the mild weather conditions experienced. Ad libitum drinking was adequate to facilitate rehydration in firefighters upon completion of their emergency firefighting work shift. © 2011 Elsevier Ltd and The Ergonomics Society. Source

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