@article {bnh-1813, title = {The likelihood of ignition of dry-eucalypt forest litter by firebrands}, journal = {International Journal of Wildland Fire}, volume = {24}, year = {2015}, month = {03/2015}, pages = {225-235}, type = {Journal}, chapter = {225}, abstract = {

Ignition probability of litter of dry-eucalypt forest by standard flaming and glowing firebrand samples was tested in a wind tunnel. Standard flaming firebrands were sections of bamboo sate stick 50\ mm long, and flamed for ~9\ s in still air. Standard glowing samples were sections of shed bark of\ Eucalyptus globulus\ 50\ mm long, 15\ mm wide and ~2\ mm in thickness. These were burnt at their terminal velocities and at deposition had a mean mass of 0.2\ g and would remain glowing for 2.5\ min in wind. Ignition was tested using air speeds of zero, 1 and 2\ m\ s{\textendash}1, and oven-dried fuel moisture contents between 4 and 21\%. For flaming samples, ignition probability was insensitive to variation in fuel and airflow characteristics and was a function of wind (no wind or wind) and fuel moisture content. For glowing samples, ignition probability was a function of fuel moisture content and wind speed. The models confirm the dominating influence of fuel moisture, are consistent with expert observations in the field and provide a practical measure of ignition likelihood by firebrands. It is argued that airflow turbulence and relative humidity are potentially significant for ignition by glowing firebrands.

}, doi = {10.1071/WF14048}, url = {http://www.publish.csiro.au/nid/114/paper/WF14048.htm}, author = {Ellis, Peter} } @article {BF-3146, title = {Changes in behaviour of fire in dry eucalypt forest as fuel increases with age}, journal = {Forest Ecology and Management}, volume = {271}, year = {2012}, month = {5/2012}, pages = {170 - 181}, abstract = {This paper describes the conduct and results of a series of high-intensity experimental fires in dry eucalypt forest under summer conditions of high fire danger. Simultaneous experimental fires were conducted at two locations with contrasting understorey and fuel structures that had developed over periods of 2{\textendash}22 years after prescribed burning. Fuel characteristics (load, height, and visual scores that gave a numerical rating of structure) and wind speed were correlated with fire spread, flame height, firebrand density and spotting distance, all of which increased with time since the last fire. The near-surface layer was the dominant stratum affecting headfire rate of spread during these experiments and provided a common descriptor for fuel types that were visually very different because of the characteristics of the understorey shrubs. Visual hazard scores that reflected the quantity and arrangement of surface and near-surface fuel were more strongly correlated with most fire behaviour variables than were the corresponding fuel load variables. Visual ratings of fuel structure should be suitable to include in algorithms to predict fire behaviour and fire threat.}, issn = {03781127}, doi = {10.1016/j.foreco.2012.02.003}, author = {Lachlan W. McCaw and J.S. Gould and Phillip Cheney, N. and Ellis, Peter and Wendy R. Anderson} } @article {BF-3100, title = {Field evaluation of two image-based wildland fire detection systems}, journal = {Fire Safety Journal}, volume = {47}, year = {2012}, month = {1/2012}, pages = {54 - 61}, abstract = {Rapid detection of wildfire outbreaks is a critical component of fire management because suppression activities are most effective when fires are small. One method of fire detection and location is computer analysis of images from sensors mounted on towers. In this paper we report on a trial of two image-based detection systems under operational conditions in forests and pasture in south-eastern Australia. The systems were deployed for 3 months in autumn, 2010, during which time a total of 12 experimental fires, 31 planned fires lit by public land management agencies, approximately 250 planned fires lit by private individuals, and 1 unplanned fire were recorded. Both image-based systems were able to detect and locate fires. They performed well for larger planned fires but poorly for small fires (View the MathML source area) at moderate distances (10{\textendash}20 km). System performance was compared to a human observer for a subset of fires. For these fires the human observer had a higher detection rate and shorter reporting time than the image-based systems. All methods of detection had a similar level of error for locating fires in the landscape once they had been detected. Operator skill was an important factor in the performance of all systems. Image-based fire detection could be a useful complement to other detection methods already in use in Australia.}, doi = {10.1016/j.firesaf.2011.11.001}, author = {Stuart Matthews and Sullivan, Andrew and J.S. Gould and Hurley, R.J. and Ellis, Peter and Larmour, John} } @article {BF-3543, title = {A Review of Empirical Studies of Fireband Behaviour: Part A}, year = {2011}, abstract = { The vast majority of empirical research of firebrand behaviour during {\textquoteleft}flight{\textquoteright} has employed wood samples of regular shape and combusted while tethered in an airflow at a range of fixed velocities or at a relative airflow equivalent to their terminal velocity. Ideally, firebrand samples should be combusted at an air velocity equal to their terminal velocity, and untethered. Australia arguably experiences the worst cases of spotting in the world, and this has largely been attributed to the firebrand characteristics of eucalypt bark, which varies enormously in morphology. Models for firebrand behaviour developed using wood samples may at best be suitable for a limited number of bark morphologies, and then only if validated. One study has quantified the firebrand characteristics of messmate stringybark, which is notorious for intense short distance spotting, using small samples of up to 6 g burnt untethered and hence burning at their terminal velocity. A very limited study of shed bark cylinders of a {\textquoteleft}gum bark{\textquoteright} type has failed to demonstrate that this type could cause the cases of extreme distance spotting for which the type is notorious. Thus, there is a need to validate the existing work on messmate stringybark and extend it to include large samples, possibly by investigating another notorious stringybark, for example. In addition, there is a need to investigate possible agents for the long-distance spotting which is a feature of major fires, perhaps initially focussing on the types notorious for this type of spotting, but also investigating other firebrand material reported in the field. }, author = {Ellis, Peter} } @article {BF-3570, title = {A review of empirical studies of firebrand behaviour: Part B}, year = {2011}, abstract = {Ignition probability and early spotfire growth are critical to the impact of given levels of firebrand generation and transport. There is little information on fuelbed ignition probability and early spotfire growth for firebrand and fuelbed combinations relevant to Australia, especially for conditions of Very High to Extreme Fire Danger during which the hazard and potential losses caused by spotting are greatest. Hence, there is a need to further investigate these processes.}, author = {Ellis, Peter} } @article {BF-2578, title = {Fire Dynamics in Mallee Heath Vegetation}, year = {2010}, author = {Cruz, Miguel G. and Stuart Matthews and J.S. Gould and Ellis, Peter and Henderson, M. K. and Knight, IK and Watters, J} } @article {BF-1009, title = {Field Guide- Fuel assessment and fire behaviour prediction in dry euclaypt forest}, volume = {82}, year = {2007}, month = {11/01/2007}, institution = {Ensis- CSIRO \& Department of Enivironment and Conservation, WA}, author = {J.S. Gould and Lachlan W. McCaw and Cheney, NP and Ellis, Peter and Stuart Matthews} } @article {BF-1010, title = {Project Vesta- Fire in dry eucalypt Forest: Fuel structure, fuel dynamics and fire behaviour}, volume = {218}, year = {2007}, month = {11/01/2007}, institution = {Ensis- CSIRO \& Department of Enivironment and Conservation, WA}, url = {http://www.publish.csiro.au/nid/22/pid/5993.htm}, author = {J.S. Gould and Lachlan W. McCaw and Cheney, NP and Ellis, Peter and Knight, IK and Sullivan, Andrew} }