Satellite data for bushfire burn severity mapping in Australia
By Mazdak Ghasemi · Last checked 22 October 2026
How is bushfire burn severity mapped from satellites?
With optical imagery that has near-infrared and shortwave-infrared bands, compared before and after the fire. The standard index is the Normalized Burn Ratio, (NIR − SWIR) / (NIR + SWIR), as USGS describes it. Sentinel-2 and Landsat both carry those bands. Landsat is the primary source for the US Monitoring Trends in Burn Severity programme, and the NSW Government's Fire Extent and Severity Mapping uses Sentinel-2.
Which data to use
| Data | Resolution | Revisit | Record | Use |
|---|---|---|---|---|
| Sentinel-2 | 10 m (shortwave infrared 20 m) | 5 days | From June 2015 | Burn severity at the finest free resolution |
| Landsat 8 and 9 | 30 m | 16 days each, 8 together | From 2013 | Burn severity, consistent with the long Landsat record |
| Landsat 5 and 7 archives | 30 m | Archive | 1984 to 2024 | Fire history |
| NSW Fire Extent and Severity Mapping | Mapped from Sentinel-2 | Per fire | NSW fires | Official NSW severity classes, from unburnt to extreme |
How it is done
- Choose a cloud- and smoke-free image from before the fire and one from after it.
- Calculate the Normalized Burn Ratio for each: (NIR − SWIR) / (NIR + SWIR). For Landsat 8 and 9 that is (Band 5 − Band 7) / (Band 5 + Band 7); for Landsat 4 to 7, bands 4 and 7.
- Map severity from the change between the two (often called dNBR), and check it against field observations.
Limits to know
- Smoke and cloud hide the ground in the weeks around a fire, so suitable scenes can be weeks apart.
- Sentinel-2's shortwave-infrared bands are 20 m, so its burn ratio is coarser than its 10 m visible bands.
- Landsat 7 scenes since June 2003 have gaps from the Scan Line Corrector failure.
- Satellite severity classes need field checks before they are used for decisions.
Who does this in practice
- The US Monitoring Trends in Burn Severity programme maps burn severity with Landsat as its primary source, at 30 m, and also uses Sentinel-2.
- The NSW Government's Fire Extent and Severity Mapping estimates severity from Sentinel-2 imagery with machine learning.
What Terrascout returns
The real result for “Assess bushfire burn severity in the Blue Mountains NSW” (Blue Mountains, NSW), captured on 22 October 2026: the top 3 of 6 sources.
| # | Source | Type | Resolution | Cost | Fit |
|---|---|---|---|---|---|
| 1 | Sentinel-2 MSI | Optical | 10 m | No data fee | 98 |
| 2 | Landsat 8 OLI/TIRS | Optical | 30 m | No data fee | 92 |
| 3 | Landsat 9 OLI-2/TIRS-2 | Optical | 30 m | No data fee | 92 |