Fire is a natural ecological process in the Australian landscape, with many vegetation communities adapted to fire.
Fire extent and severity mapping (FESM) uses satellite imagery and machine learning to deliver timely maps of fire severity. These maps help us:
- classify and model fires
- understand relationships between fuels and fire behaviour
- interpret how a fire has changed the landscape
- provide information about the damage a fire has caused to the tree canopy and understory
- gather evidence about how far each fire has spread
- support better land and fire management
- support on-ground actions and conservation planning.
Before FESM was developed, vegetation loss due to fire was reported as part of our Statewide Landcover and Tree Study reporting until 2018.
In 2021 we started publishing annual reports on fire extent and severity at a landscape scale using FESM.
Annual report
Each FESM annual report summarises the fire season for that year and is accompanied by data analyses for the reported fire season and comparisons with previous fire seasons.
Data is available through the Sharing and Enabling Environment Data portal.
When maps are produced
Maps for individual fires can be produced once a fire event has stabilised. We also produce summary maps annually after each fire season to investigate changes in vegetation trends over time. This enables our scientists to better understand how future fire events may unfold and the potential impacts of these events on the environment.
The FESM state-wide map and datasets are available on the Sharing and Enabling Environmental Data (SEED) portal or by searching ‘FESM SEED’. FESM is part of collaborative research being undertaken as part of the NSW Bushfire Risk Management Research Hub to improve fire management strategies and reduce the risk bushfires pose to people, property and the environment.
Mapping method
Since 2018, we’ve been developing a mapping system to deliver near-real time maps of fire severity to help classify and model fires.
A prototype operational system was deployed in December 2019 to provide rapid-response severity mapping to support the Department’s operations during the emerging black summer bushfire crisis. A refined, fully operational system was launched in July 2020 that:
- delivers mapping in near-real time
- links with the Rural Fire Service IT infrastructure
- automates the application of the modelling to new fires.
Our scientists are leading continued refinement and development of FESM, which involves the NSW Rural Fire Service and Natural Resources Commission. The program will benefit from capturing and incorporating additional training data from future fires.
The Supporting fire management with the fire extent and severity maps fact sheet contains more information about the fire mapping methodology.
Fire severity classes
The FESM system designates areas into standardised fire severity classes to facilitate comparison of different fires across the landscape. This helps land managers and researchers understand how fires have affected the landscape and informs:
- on-ground conservation
- fire management actions
- recovery efforts.
The algorithm uses ecologically meaningful definitions of ‘severity’ to define levels of canopy scorch and consumption. This enables us to:
- gain a more nuanced understanding of the impact of fires on the environment
- provide information about the potential impact on species and habitats.
|
Pixel Value |
Severity class |
Description |
Photo interpretation cues (false colour infra-red) |
Percentage foliage fire affected |
|
0 |
Unburnt |
Unburnt surface with unburnt canopy |
Dark red (live understorey) between the dark red tree crowns |
0% canopy and understorey burnt |
|
2 |
Low |
Burnt understory with unburnt canopy |
Dark grey (burnt understorey) between the dark red tree crowns |
>10% burnt understorey |
|
3 |
Moderate |
Partial canopy scorch |
A mixture of green, orange and brown colours in tree canopies |
20-90% canopy scorch |
|
4 |
High |
Complete canopy scorch (+/– partial canopy consumption) |
No green or orange, but an even brown colour in tree canopies |
>90% canopy scorched |
|
5 |
Extreme |
Complete canopy consumption |
Mostly black and dark grey, largely no canopy cover |
>50% canopy biomass consumed |
Table note: Fire severity classification ruleset based on high-resolution aerial photo interpretation, adapted from McCarthy et al. (2017) and Collins et al. (2018).
