The NSW Government is currently committed to treating an average of 135,000 hectares of national park estate each year in hazard reduction burns, as part of its overall bushfire risk management. This strategy assumes the regular occurrence of periods, or windows, during which weather is favourable for conducting the burns. However, we do not fully understand the typical timing and frequency of these hazard-reduction burn windows across the NSW landscape. Without this knowledge, it is also difficult to predict the impact of climate change upon burn windows.

This project takes a multi-pronged approach to the problem of developing a ‘climatology’ of present and future hazard reduction burn windows. First, we analyse the frequency of various meteorological thresholds currently used to guide burn planning. Secondly, we create a climatology for the extended burn seasons of autumn (March to June) and spring (July to October), during which the majority of hazard reduction burns take place. Finally, we examine historical records of hazard reduction burns in order to determine the weather conditions during which they took place. These separate measures of hazard reduction burn windows are then applied to output from a 12-member, regional climate model ensemble to project changes in these windows out to 2030 and 2070.

This is a joint project by the Science Division of the Office of Environment and Heritage and the NSW National Parks and Wildlife Service. By linking science with practice, we aim to conduct relevant research that will underpin good practice in hazard reduction burns management.