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ID · Indonesia · –

Bulungan fire, 29 August 2026 Bulungan, Berau

Out · last measured on 2 Sept 2026

The fire started on 29 August 2026 in Bulungan, Indonesia, and satellites saw it burning for 5 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 1,663 hectares from heat detections, spread across 2 municipalities.

Number 816 in Indonesia in 2026, of 972.

GWIS near-real-time perimeter, from the layer that changed in October 2025: this fire is not compared with fires from earlier years, because since then the GWIS layer gives more and larger perimeters.

Compare with…

We have the GWIS perimeter for this fire, but not yet its hotspots: NASA publishes the yearly hotspot archive only once the year closes. The page picks them up automatically when they are available.

Burnt area
1,663ha
GWIS perimeter (Copernicus)
Duration
5days
29 Aug 2026 – 2 Sept 2026
Municipalities hit
2
regencies
Started on
29 Aug
2026
Danger at start
23
High · FWI index

Where it burned

The weather it burned in

36°high
36km/h · peak gust
32%lowest humidity

It had gone 3 days without rain (1 mm or more) when it started. Rain came after the fire: 3.4 mm on 4 Sept.

This area had burned before

44% of the perimeter overlaps earlier fires recorded since 2016: 166 ha in 2018, 287 ha in 2019, 107 ha in 2023, 121 ha in 2024, 423 ha in 2025. Part of it burned more than once, so the yearly figures add up to more than the 735 ha that had burned before.

How big is it?

10 km
It burned the equivalent of 1.1% of the area of London (17 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. Bulungan where it started
    1,060 ha
    0.1 %
  2. 615 ha
    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 area0.62 ha
Residents≈ 100

Inside the perimeter there were about 0.62 hectares of built-up land and about 100 residents (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)

Day High Min. humidity Peak gust Rain Danger (FWI)
29 Aug 36.2 °C 32 % 34 km/h 0.0 mm High 23
30 Aug 35.3 °C 41 % 26 km/h 0.3 mm High 22
31 Aug 36.5 °C 39 % 33 km/h 0.0 mm High 25
1 Sept 36.0 °C 38 % 36 km/h 0.5 mm High 25
2 Sept 34.7 °C 42 % 26 km/h 0.1 mm High 23
3 Sept after 33.8 °C 50 % 22 km/h 0.5 mm Moderate 19
4 Sept after 34.2 °C 50 % 27 km/h 3.4 mm Very low 5

Before and after, from space

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

Before · 22 Aug 2026
After · 9 Sept 2026

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 2 September 2026 the air beside the fire reached 250 µg/m³ of PM2.5. That day averaged 158: 11 times the WHO daily guideline (15).

PM2.5 peak250 µg/m³
Days over the guideline10 days
PM10257 µg/m³
Optical depth3.59
27 Aug29 Aug31 Aug2 Sept4 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)

Frequently asked questions

How long did the Bulungan fire last?
GWIS (Copernicus) dates it between 29 August 2026 and 2 September 2026: 5 days between the first and last heat detection of the perimeter.
How much area did it burn?
The perimeter GWIS (Copernicus) rebuilt from heat detections is 1,663 hectares (16.6 km²). It is an estimate: official national figures may differ.
Which municipalities burned?
The fire entered 2 municipalities: Bulungan (1,060 ha, 0.1 %); Berau (615 ha, 0.0 %).
What was the weather like?
During the fire the temperature reached 36.5 °C, humidity dropped to 32 % and gusts hit 36 km/h. The fire danger index (FWI) reached 25, class High.
Where does this data come from?
From the GWIS (Copernicus) burnt perimeter, NASA FIRMS VIIRS hotspots and the administrative boundaries of Indonesia (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: 112 · Emergency number and official warnings

Satellite cross-check

History of this page Changes in area, dates, name, official record or merged pages, compared every night since 24 October 2026.

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 112.

How we know this
  • Perimeter: GWIS (Copernicus), rebuilt from heat detections rather than mapped on imagery.
  • Dates from the perimeter: the VIIRS detections inside it did not change them. No 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.

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 3.0 Intergovernmental Organisations (CC BY 3.0 IGO)). 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.