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AU · Australia · –

Roper Gulf fire, 17 August 2023 Roper Gulf, West Arnhem

Out · last detection 27 Sept 2023, 05:11 UTC

The fire started on 17 August 2023 in Roper Gulf, Australia, and satellites saw it burning for 42 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 18,912 hectares from heat detections, spread across 2 municipalities.

This entry is probably a savanna fire in Australia’s tropical north, not a bushfire like those in the south of the country. Millions of hectares of northern savanna and grassland burn every year: much of it in burns lit on purpose early in the dry season (traditional fire management, parks and cattle stations), the rest in grass fires that return to the same ground every few years. This is our assumption, based on the location; it is not confirmed. That is why it is left out of the wildfire rankings.

Burnt area
18,912ha
GWIS perimeter (Copernicus)
Duration
42days
17 Aug 2023 – 27 Sept 2023
Municipalities hit
2
local government areas
Started on
17 Aug
2023
Heat detections
1,088
in a single hotspot: 58 MW
Danger at start
34
High · FWI index
Average daily power
182MW
detected power per day, on average

Where it burned

HOTSPOTS BY DAY 17 Aug27 Sept
27 Sept 2023

How it evolved, day by day

17 Aug 2023 · 301 MW · 29 18 Aug 2023 · 411 MW · 35 19 Aug 2023 · 253 MW · 23 20 Aug 2023 · 8 MW · 5 21 Aug 2023 · 26 MW · 5 22 Aug 2023 · 81 MW · 24 23 Aug 2023 · 309 MW · 20 24 Aug 2023 · 197 MW · 36 25 Aug 2023 · 321 MW · 32 26 Aug 2023 · 60 MW · 22 27 Aug 2023 · 220 MW · 29 28 Aug 2023 · 137 MW · 22 29 Aug 2023 · 108 MW · 17 30 Aug 2023 · 205 MW · 20 31 Aug 2023 · 34 MW · 12 1 Sept 2023 · 126 MW · 16 2 Sept 2023 · 82 MW · 15 3 Sept 2023 · 387 MW · 27 4 Sept 2023 · 120 MW · 24 5 Sept 2023 · 94 MW · 16 6 Sept 2023 · 120 MW · 18 7 Sept 2023 · 52 MW · 7 8 Sept 2023 · 13 MW · 3 9 Sept 2023 · 7 MW · 3 10 Sept 2023 · 7 MW · 3 11 Sept 2023 · 13 MW · 6 12 Sept 2023 · 29 MW · 10 13 Sept 2023 · 83 MW · 16 14 Sept 2023 · 295 MW · 18 15 Sept 2023 · 211 MW · 38 16 Sept 2023 · 308 MW · 82 17 Sept 2023 · 587 MW · 93 18 Sept 2023 · 777 MW · 91 19 Sept 2023 · 505 MW · 95 20 Sept 2023 · 751 MW · 74 21 Sept 2023 · 113 MW · 35 22 Sept 2023 · 125 MW · 29 23 Sept 2023 · 74 MW · 15 24 Sept 2023 · 32 MW · 9 25 Sept 2023 · 25 MW · 4 26 Sept 2023 · 12 MW · 5 27 Sept 2023 · 30 MW · 5
17 Aug 26 Aug 4 Sept 18 Sept

Fire radiative power detected each day, in megawatts, and number of hotspots. The magenta bar marks the peak day.

The weather it burned in

36°high
59km/h · peak gust
13%lowest humidity

It had gone more than two months without rain (1 mm or more) when it started.

This area had burned before

98% of the perimeter overlaps earlier fires recorded since 2016: 6,033 ha in 2016, 8,525 ha in 2017, 7,013 ha in 2018, 4,694 ha in 2019, 11,808 ha in 2020, 4,157 ha in 2021, 13,717 ha in 2022. Part of it burned more than once, so the yearly figures add up to more than the 18,486 ha that had burned before.

How big is it?

10 km
It burned the equivalent of 12% of the area of London (189 km² against 1,583 km²).

London boundary: geoBoundaries · Office for National Statistics (Open Government Licence v3.0).

This compares size, not location: both shapes are at the same scale, north up, centred on each other.

What happened to each town

  1. Roper Gulf where it started
    18,811 ha reached on 17 Aug
    0.1 %
  2. 81 ha reached on 25 Aug
    0.0 %

Burnt area inside each municipality, from crossing the GWIS perimeter with administrative boundaries. The distance runs from the point marking the centre of each area to the nearest fire: staying a kilometre away does not mean it reached the houses.

People and buildings inside the perimeter

GHSL 2025
Built-up area< 0.1 ha
Residents< 20

Inside the perimeter there was no noticeable built-up land and almost nobody lived there (GHSL 2025, satellite-based estimate).

This is an estimate on 100 m cells, made from satellite imagery and census data: it does not mean that homes burned or that anyone was harmed. The perimeter also contains land that never burned. The GHSL 2025 epoch is a projection made from 2020 and earlier data.

Source: Global Human Settlement Layer (GHS-BUILT-S and GHS-POP R2023A), European Commission Joint Research Centre (JRC), © European Union, CC BY 4.0. Sum inside the perimeter computed by WorldFires. human-settlement.emergency.copernicus.eu

The weather day by day

ECMWF ERA5 reanalysis at the fire location, the standard reference for past weather, and the Canadian Fire Weather Index (the same system Copernicus uses), computed by WorldFires from that data. Days after the fire run until the first rain.

Open-Meteo.com (CC BY 4.0) · Copernicus Climate Change Service (ERA5)

Started with 60 days without rain: 8.2 % of the area in Australia

Day High Min. humidity Peak gust Rain Danger (FWI)
17 Aug 31.5 °C 29 % 23 km/h 0.0 mm High 34
18 Aug 33.3 °C 22 % 37 km/h 0.0 mm Very high 40
19 Aug 31.2 °C 23 % 52 km/h 0.0 mm Very high 48
20 Aug 30.1 °C 18 % 45 km/h 0.0 mm Very high 45
21 Aug 30.6 °C 18 % 41 km/h 0.0 mm Very high 43
22 Aug 30.9 °C 20 % 44 km/h 0.0 mm Very high 44
23 Aug 31.4 °C 22 % 49 km/h 0.0 mm Very high 48
24 Aug 31.8 °C 24 % 44 km/h 0.0 mm Very high 46
25 Aug 31.8 °C 19 % 54 km/h 0.0 mm Extreme 51
26 Aug 31.5 °C 17 % 56 km/h 0.0 mm Extreme 54
27 Aug 31.4 °C 23 % 54 km/h 0.0 mm Extreme 54
28 Aug 32.0 °C 22 % 53 km/h 0.0 mm Extreme 51
29 Aug 31.6 °C 22 % 52 km/h 0.0 mm Extreme 51
30 Aug 31.9 °C 18 % 46 km/h 0.0 mm Very high 48
31 Aug 32.9 °C 14 % 37 km/h 0.0 mm Very high 45
1 Sept 32.1 °C 13 % 45 km/h 0.0 mm Extreme 51
2 Sept 31.8 °C 17 % 39 km/h 0.0 mm Very high 48
3 Sept 31.8 °C 16 % 25 km/h 0.0 mm Very high 44
4 Sept 32.5 °C 20 % 25 km/h 0.0 mm Very high 42
5 Sept 33.4 °C 19 % 37 km/h 0.0 mm Very high 47
6 Sept 33.5 °C 14 % 29 km/h 0.0 mm Very high 43
7 Sept 34.4 °C 16 % 34 km/h 0.0 mm Very high 43
8 Sept 34.8 °C 18 % 43 km/h 0.0 mm Extreme 52
9 Sept 34.2 °C 14 % 59 km/h 0.0 mm Extreme 64
10 Sept 34.7 °C 22 % 56 km/h 0.0 mm Extreme 60
11 Sept 34.1 °C 16 % 54 km/h 0.0 mm Extreme 60
12 Sept 32.7 °C 20 % 48 km/h 0.0 mm Extreme 54
13 Sept 32.2 °C 21 % 55 km/h 0.0 mm Extreme 60
14 Sept 32.2 °C 21 % 47 km/h 0.0 mm Extreme 54
15 Sept 31.8 °C 17 % 56 km/h 0.0 mm Extreme 57
16 Sept 31.7 °C 22 % 53 km/h 0.0 mm Extreme 57
17 Sept 32.4 °C 19 % 50 km/h 0.0 mm Extreme 54
18 Sept 33.2 °C 20 % 43 km/h 0.0 mm Extreme 52
19 Sept 33.0 °C 18 % 37 km/h 0.0 mm Very high 46
20 Sept 34.8 °C 17 % 36 km/h 0.0 mm Very high 46
21 Sept 35.5 °C 20 % 42 km/h 0.0 mm Very high 50
22 Sept 36.5 °C 17 % 50 km/h 0.0 mm Extreme 55
23 Sept 35.5 °C 16 % 43 km/h 0.0 mm Extreme 51
24 Sept 34.8 °C 20 % 32 km/h 0.0 mm Very high 46
25 Sept 34.5 °C 20 % 33 km/h 0.0 mm Very high 45
26 Sept 35.2 °C 20 % 40 km/h 0.0 mm Very high 49
27 Sept 35.1 °C 20 % 44 km/h 0.0 mm Extreme 53
28 Sept after 34.9 °C 21 % 49 km/h 0.0 mm Extreme 56
29 Sept after 34.0 °C 26 % 48 km/h 0.0 mm Extreme 51
30 Sept after 35.3 °C 16 % 32 km/h 0.0 mm Very high 45
1 Oct after 35.8 °C 21 % 36 km/h 0.0 mm Very high 46
2 Oct after 36.6 °C 21 % 34 km/h 0.0 mm Extreme 50
3 Oct after 35.5 °C 25 % 34 km/h 0.0 mm Very high 48
4 Oct after 34.4 °C 39 % 35 km/h 0.1 mm Very high 38
5 Oct after 34.1 °C 29 % 33 km/h 0.7 mm High 35
6 Oct after 34.8 °C 24 % 47 km/h 0.0 mm Very high 46
7 Oct after 34.8 °C 16 % 41 km/h 0.0 mm Very high 47

Before and after, from space

Drag the line to compare the same ground before the fire and after it.

Before · 10 Aug 2023
After · 4 Oct 2023

If the day is cloudy, change the date: each satellite passes once a day. In false colour the burnt ground looks brown or red.

The smoke

CAMS · Copernicus

On 24 September 2023 the air beside the fire reached 17 µg/m³ of PM2.5, but no daily average passed the WHO guideline (15).

PM2.5 peak17 µg/m³
Days over the guideline0 days
PM1028 µg/m³
Optical depth0.48
20 Aug29 Aug7 Sept16 Sept25 Sept
Good Fair Moderate Poor Very poor Extremely poor

Particles from the Copernicus CAMS model at the centre of the perimeter; these are not measurements in each town. The pale bar is the worst hour, the solid one the daily average.

Open-Meteo.com (CC BY 4.0) · Copernicus Atmosphere Monitoring Service (CAMS)

Detections table · 1,088Every satellite heat detection, one by one, with time, satellite, power and coordinates.
⬇ Download CSV Times in UTC. Each detection is a 375 m pixel: a large fire yields hundreds per pass.
Date and timeSatelliteFRP (MW)LatLon

Other fires nearby

All fires in Australia

Frequently asked questions

How long did the Roper Gulf fire last?
According to the heat detections seen by satellite inside the perimeter, it burned from 17 August 2023 to 27 September 2023 (42 days). The perimeter dates it from 22 August 2023 to 27 September 2023.
How much area did it burn?
The perimeter GWIS (Copernicus) rebuilt from heat detections is 18,912 hectares (189.1 km²). It is an estimate: official national figures may differ.
Which municipalities burned?
The fire entered 2 municipalities: Roper Gulf (18,811 ha, 0.1 %); West Arnhem (81 ha, 0.0 %).
What was the weather like?
During the fire the temperature reached 36.5 °C, humidity dropped to 13 % and gusts hit 59 km/h. The fire danger index (FWI) reached 64, class Extreme.
Where does this data come from?
From the GWIS (Copernicus) burnt perimeter, NASA FIRMS VIIRS hotspots and the administrative boundaries of Australia (geoBoundaries). It is not an official report.

Where to verify it

A satellite detection is not an official report. Final figures and the fire’s status are published by each country’s emergency service.

Emergency number: 000 · Emergency number and official warnings

Satellite cross-check

History of this page · 1 Changes in area, dates, name, official record or merged pages, compared every night since 24 October 2026.
  1. Start date: 22 August 2023 → 17 August 2023.

RSS Changes to this page With cross-checks and a citable version

Does something look wrong on this page?

This page is built from satellite data and official records, and it sometimes gets things wrong: the wrong dates, the wrong town, two fires merged into one, or something that was not a wildfire at all. If you know this fire first-hand (you live nearby, saw it, fought it or reported on it), tell us what really happened and we will check it.

Report an error
What do you think is wrong?

We will only use your email to reply about this report. Privacy. This is not an emergency service: if there is a fire now, call 000.

How we know this
  • Perimeter: GWIS (Copernicus), rebuilt from heat detections rather than mapped on imagery.
  • Dates adjusted with the VIIRS detections inside the perimeter, which said 22 August 2023 to 27 September 2023. 1,088 Suomi-NPP VIIRS detections on those dates.
  • We have not matched this page with any official record.
  • Weather: Copernicus ERA5 reanalysis at the fire location, in cells of about 25 km.
  • Built-up area and population come from the JRC Global Human Settlement Layer (epoch 2025, 100 m cells), summed inside the perimeter: an estimate of what was there, not a damage count.
  • Probably a vegetation burn: not counted in the totals.

How we build fire pages: methodology

Where this data comes from

The perimeter comes from the Copernicus Global Wildfire Information System (GWIS), which rebuilds it from MODIS and VIIRS heat detections and publishes it under CC BY 4.0. It is not measured on imagery as in Europe, so it is an estimate. Heat detections come from the VIIRS sensors aboard Suomi-NPP and NOAA-20, distributed by NASA FIRMS at 375 m resolution. Municipal boundaries come from geoBoundaries ADM2 (Creative Commons Attribution 4.0 International (CC BY 4.0)). The area per municipality is computed by WorldFires by crossing the perimeter with those boundaries, so it may differ from each country’s official figure.