Lead end user
This project will use high-resolution modelling, together with the full range of meteorological data, to better understand and predict several important meteorological natural hazards, including fire weather, tropical cyclones, severe thunderstorms, and heavy rainfall.
While a number of advances have been made in understanding bushfire development under extreme conditions, these have not been quantified in a manner that is suitable for inclusion in fire behaviour modelling framework. One of the main aims of this project is to develop statistical models that allow for the inclusion of dynamic effects when they are important – that is, when fires grow sufficiently large and complex.
Bushfires affect the surrounding atmosphere because of the large amount of heat and moisture that results from the combustion and is deposited in the atmosphere. The atmospheric response to this energy input includes changes to the local winds, modification of the boundary layer, and the development of pyroconvective clouds. These changes can profoundly modify the evolution of the fire.
Fire behaviour in dry eucalypt forests in Australia (and in many other vegetation types to a lesser extent) is characterised by the occurrence of spotfires—new fires ignited by the transport of burning debris such as bark ahead of an existing fire. Under most burning conditions, spotfires play little role in the overall propagation of a fire, except where spread is impeded by breaks in fuel or topography and spotfires allow these impediments to be overcome. However, under conditions of severe bushfire behaviour spotfire occurrence can be so prevalent that spotting becomes the dominant propagation mechanism and the fire spreads as a cascade of spotfires forming a ‘pseudo’ front.