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Cujubim fire, 18 August 2021 Cujubim

Out · last detection 28 Aug 2021, 17:54 UTC

The fire started on 18 August 2021 in Cujubim, Brazil, and satellites saw it burning for 13 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 3,627 hectares from heat detections, spread across a single municipality.

It is the 209th largest in Rondônia since 2016 (of 300 with a page). Number 634 in Brazil in 2021, of 814.

Compare with…
Burnt area
3,627ha
GWIS perimeter (Copernicus)
Duration
13days
18 Aug 2021 – 30 Aug 2021
Municipalities hit
1
municipalities
Started on
18 Aug
2021
Heat detections
255
in a single hotspot: 501 MW
Danger at start
34
High · FWI index
Average daily power
526MW
detected power per day, on average

Where it burned

HOTSPOTS BY DAY 18 Aug30 Aug
28 Aug 2021

How it evolved, day by day

18 Aug 2021 · 2 MW · 1 19 Aug 2021 · 10 MW · 1 21 Aug 2021 · 885 MW · 13 22 Aug 2021 · 30 MW · 11 23 Aug 2021 · 171 MW · 11 24 Aug 2021 · 2 MW · 2 25 Aug 2021 · 2,767 MW · 68 26 Aug 2021 · 1,091 MW · 71 27 Aug 2021 · 174 MW · 49 28 Aug 2021 · 125 MW · 28
18 Aug 21 Aug 23 Aug 25 Aug 27 Aug

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

The weather it burned in

38°high
38km/h · peak gust
21%lowest humidity

It had gone 50 days without rain (1 mm or more) when it started. Rain came after the fire: 1.1 mm on 4 Sept.

This area had burned before

91% of the perimeter overlaps earlier fires recorded since 2016: 1,903 ha in 2017, 609 ha in 2018, 3,814 ha in 2019, 1,852 ha in 2020. Part of it burned more than once, so the yearly figures add up to more than the 3,315 ha that had burned before.

How big is it?

10 km
It burned the equivalent of 2.3% of the area of London (36 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. Cujubim 14,863 inhabitants where it started
    3,649 ha reached on 18 Aug
    0.9 %

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 2020
Built-up area< 0.1 ha
Residents< 20

Inside the perimeter there was no noticeable built-up land and almost nobody lived there (GHSL 2020, 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.

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)
18 Aug 36.0 °C 26 % 26 km/h 0.0 mm High 34
19 Aug 36.7 °C 21 % 19 km/h 0.0 mm High 37
20 Aug 34.8 °C 34 % 24 km/h 0.0 mm High 34
21 Aug 35.9 °C 28 % 25 km/h 0.0 mm High 34
22 Aug 36.6 °C 30 % 24 km/h 0.0 mm High 36
23 Aug 36.6 °C 21 % 24 km/h 0.0 mm Very high 39
24 Aug 36.2 °C 30 % 28 km/h 0.0 mm High 38
25 Aug 37.1 °C 37 % 38 km/h 0.0 mm High 36
26 Aug 37.5 °C 34 % 30 km/h 0.0 mm High 36
27 Aug 35.8 °C 34 % 20 km/h 0.1 mm High 35
28 Aug 35.1 °C 38 % 23 km/h 0.1 mm High 34
29 Aug 33.6 °C 45 % 28 km/h 3.1 mm Low 10
30 Aug 33.9 °C 43 % 26 km/h 0.3 mm Moderate 20
31 Aug after 34.3 °C 42 % 21 km/h 0.5 mm High 23
1 Sept after 33.4 °C 44 % 25 km/h 0.2 mm High 23
2 Sept after 35.0 °C 41 % 25 km/h 0.0 mm High 24
3 Sept after 34.8 °C 40 % 17 km/h 0.0 mm High 25
4 Sept after 35.8 °C 36 % 26 km/h 1.1 mm High 21

Before and after, from space

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

Before · 11 Aug 2021
After · 6 Sept 2021

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

Detections table · 255Every 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 Brazil ›

Frequently asked questions

How long did the Cujubim fire last?
According to the heat detections seen by satellite inside the perimeter, it burned from 18 August 2021 to 30 August 2021 (13 days). The perimeter dates it from 23 August 2021 to 30 August 2021.
How much area did it burn?
The perimeter GWIS (Copernicus) rebuilt from heat detections is 3,627 hectares (36.3 km²). It is an estimate: official national figures may differ.
Which municipalities burned?
The fire only entered Cujubim (3,649 ha, 0.9 %).
What was the weather like?
During the fire the temperature reached 37.5 °C, humidity dropped to 21 % and gusts hit 38 km/h. The fire danger index (FWI) reached 39, class Very high.
Where does this data come from?
From the GWIS (Copernicus) burnt perimeter, NASA FIRMS VIIRS hotspots and the administrative boundaries of Brazil (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: 193 · 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: 23 August 2021 → 18 August 2021.

RSS Changes to this page

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 193.

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 23 August 2021 to 30 August 2021. 255 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 2020, 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.