Burned area
satellite only12,188ha
Perimeter published by GWIS (Copernicus).
- Source
- GWIS (Copernicus)
- Date
- 18 Sept 2021 – 29 Sept 2021
+− cross-check
No official record is matched to this page to compare it with.
BW · Botswana · –
Ghanzi fire, 18 September 2021 Ghanzi
Out · last detection 29 Sept 2021, 12:45 UTC
The fire started on 18 September 2021 in Ghanzi, Botswana, and satellites saw it burning for 12 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 12,188 hectares from heat detections, spread across a single municipality.
It is the 50th largest in Ghanzi since 2016 (of 416 with a page). Number 50 in Botswana in 2021, of 406.
Use this data
Compare with…
Use this data
Fire page data · version 2026-10-27matches the official recordwith caveatssatellite onlymodel
When copying, the sentence is
Tick the figures you want: they make up the lede and the CSV.
Duration by satellite
satellite only12days
18 Sept 2021 to 29 Sept 2021: first and last day with fire on the page.
- Source
- GWIS (Copernicus) · NASA FIRMS · VIIRS
- Date
- last detection: 29 Sept 2021, 12:45 UTC
+− cross-check
Satellites pass a few times a day and cloud or smoke can hide the fire: a lack of detections is not an official extinction. Each country’s emergency service declares a fire contained or out.
Start
satellite only18 Sept 2021
First day with fire seen by the satellites or the perimeter.
- Source
- GWIS (Copernicus) · NASA FIRMS · VIIRS
- Date
- 18 Sept 2021
+− cross-check
No official record is matched to this page, so the alert time and the cause are not known here.
Hotspots
satellite only439
VIIRS detections at 375 m. Most intense hotspot: 126 MW.
- Source
- NASA FIRMS · VIIRS (Suomi NPP)
- Date
- 18 Sept 2021 – 29 Sept 2021
+− cross-check
There is no official record to compare with. Each hotspot is a pixel detected in one satellite pass, not a separate fire.
The worst day
satellite only1,995MW
Total radiative power on 27 September 2021; hotspots that day: 121.
- Source
- NASA FIRMS · VIIRS (FRP)
- Date
- 27 Sept 2021
+− cross-check
Fire radiative power (FRP) measures the energy the fire gives off when the satellite passes. Added up by day, it compares intensity, not area.
Danger at the start
model54.0FWI · extreme
Fire Weather Index (Canadian system) computed by WorldFires for the day the fire started. Consecutive days without rain before: 60.
- Source
- WorldFires calculation (Canadian FWI system)
- Date
- 18 Sept 2021, local noon
- Model
- ERA5 0,25° (ECMWF · Copernicus C3S) · Open-Meteo.com
+− cross-check
This is an index computed from weather model data, not a measurement of the fire nor an official warning. Danger warnings are issued by each country’s authority. Emergency number and official warnings
Weather during the fire
model37.3°C · 11% RH
High of 37.3 °C and minimum humidity of 11% on 29 September 2021; gusts of 43 km/h on 20 September 2021.
- Source
- weather model at the fire’s grid cell
- Date
- 18 Sept 2021 – 29 Sept 2021
- Model
- ERA5 0,25° (ECMWF · Copernicus C3S) · Open-Meteo.com
+− cross-check
These are model values for a cell of about 25 km, not from a weather station: they may differ from what was measured on the ground.
This page’s change log has been kept since 24 October 2026: every night what it publishes is compared and the difference is logged. Anything earlier is reconstructed from each source’s date and marked as reconstructed.
Show
-
· reconstructed weatherWeather and FWI computed from the ERA5 reanalysis
-
logStart date: 25 September 2021 → 18 September 2021.
-
· reconstructed GHSLPopulation and built-up area computed
What was saved on 27 October 2026
Every night a snapshot of what the page shows is saved. If anything changes, it appears in the list as a log entry.
- Area
- 12,188 ha
- Dates
- 18 Sept 2021 – 29 Sept 2021
- Name
- Ghanzi
- Official record
- —
Versioned permanent link
https://worldfires.org/en/fire/ghanzi-2021-09-29?v=2026-10-27A version keeps the area, dates, name and official record; the area as it was logged (changes under 2% are not logged). The map, hotspots and weather always show today’s data.
Citation
A lede of about 60 words figures only, no adjectives
CSV for this fire ghanzi-2021-09-29.csv · daily, no individual hotspots
| fecha | focos_viirs | frp_mw | tmax_c | tmin_c | hr_min_pct | viento_max_kmh | racha_max_kmh | precip_mm | fwi | clase_fwi | dentro_del_incendio |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 2021-09-18 | 1 | 9 | 28.3 | 14.2 | 16 | 20.9 | 40.7 | 0 | 54 | extremo | 1 |
| 2021-09-19 | 0 | 0 | 30.3 | 12.9 | 30 | 20.7 | 39.6 | 0 | 44.4 | muy_alto | 1 |
| 2021-09-20 | 1 | 1 | 34.2 | 17.7 | 14 | 18.7 | 43.2 | 0 | 61.5 | extremo | 1 |
| 2021-09-21 | 50 | 100 | 32.4 | 16.1 | 9 | 16.9 | 33.8 | 0 | 64.3 | extremo | 1 |
| 2021-09-22 | 20 | 163 | 29.7 | 15 | 15 | 21.8 | 42.5 | 0 | 59.6 | extremo | 1 |
| 2021-09-23 | 1 | 1 | 30.4 | 12.2 | 23 | 17.4 | 35.3 | 0 | 51.6 | extremo | 1 |
| 2021-09-24 | 0 | 0 | 33 | 13.2 | 17 | 13.3 | 32 | 0 | 52.5 | extremo | 1 |
| 2021-09-25 | 7 | 8 | 35.4 | 12 | 7 | 14.8 | 34.6 | 0 | 70.6 | muy_extremo | 1 |
| 2021-09-26 | 79 | 1,036 | 35.6 | 16.6 | 13 | 13.7 | 32.8 | 0 | 65.1 | extremo | 1 |
| 2021-09-27 | 121 | 1,995 | 35.4 | 18.3 | 11 | 17.1 | 36.4 | 0 | 71.8 | muy_extremo | 1 |
| 2021-09-28 | 74 | 1,273 | 36.5 | 16 | 10 | 17.1 | 37.4 | 0 | 75.3 | muy_extremo | 1 |
| 2021-09-29 | 85 | 1,909 | 37.3 | 18.9 | 11 | 18.1 | 40 | 0 | 82.4 | muy_extremo | 1 |
| 2021-09-30 | 0 | 0 | 34.2 | 21.4 | 24 | 30.1 | 58 | 1.1 | 95.1 | muy_extremo | 0 |
It is generated in your browser from this page’s data: one file per fire, aggregated by day and without individual hotspots.
Live widget for your story
It updates itself while the fire is still active and links to this page. Free, with the attribution shown at the bottom.
Sources for this page: GWIS (Copernicus), NASA FIRMS (VIIRS), ERA5 (ECMWF/Copernicus C3S) · Open-Meteo.com (CC BY 4.0), GHSL (JRC). Open-Meteo.com · How we build fire pages: methodology
- Burnt area
- 12,188ha
- GWIS perimeter (Copernicus)
- Duration
- 12days
- 18 Sept 2021 – 29 Sept 2021
- Municipalities hit
- 1
- subdistricts
- Started on
- 18 Sept
- 2021
- Heat detections
- 439
- in a single hotspot: 126 MW
- Danger at start
- 54
- Extreme · FWI index
- Average daily power
- 650MW
- detected power per day, on average
Where it burned
HOTSPOTS BY DAY
18 Sept29 Sept
29 Sept 2021
How it evolved, day by day
18 Sept
21 Sept
23 Sept
27 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
37°high
43km/h · peak gust
7%lowest humidity
It had gone more than two months without rain (1 mm or more) when it started. Rain came after the fire: 1.1 mm on 30 Sept.
This area had burned before
No earlier perimeters overlap this fire since 2016, when the satellite record begins.
How big is it?
London boundary: geoBoundaries · Office for National Statistics (Open Government Licence v3.0).
Paris boundary: geoBoundaries · Institut national de l'information géographique et forestière (IGN-F) (Etalab Open License 2.0).
Madrid boundary: geoBoundaries · Open Data ESRI, IGN Central Registry of Cartography Area (CC BY 4.0).
Berlin boundary: geoBoundaries · Federal Agency for Cartography and Geodesy (dl-de/by-2-0).
This compares size, not location: both shapes are at the same scale, north up, centred on each other.
What happened to each town
-
Ghanzi where it started12,276 ha reached on 18 Sept0.1 %
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 2020Built-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)
Started with 60 days without rain: 71 % of the area in Botswana
| Day | High | Min. humidity | Peak gust | Rain | Danger (FWI) |
|---|---|---|---|---|---|
| 18 Sept | 28.3 °C | 16 % | 41 km/h | 0.0 mm | Extreme 54 |
| 19 Sept | 30.3 °C | 30 % | 40 km/h | 0.0 mm | Very high 44 |
| 20 Sept | 34.2 °C | 14 % | 43 km/h | 0.0 mm | Extreme 62 |
| 21 Sept | 32.4 °C | 9 % | 34 km/h | 0.0 mm | Extreme 64 |
| 22 Sept | 29.7 °C | 15 % | 42 km/h | 0.0 mm | Extreme 60 |
| 23 Sept | 30.4 °C | 23 % | 35 km/h | 0.0 mm | Extreme 52 |
| 24 Sept | 33.0 °C | 17 % | 32 km/h | 0.0 mm | Extreme 52 |
| 25 Sept | 35.4 °C | 7 % | 35 km/h | 0.0 mm | Very extreme 71 |
| 26 Sept | 35.6 °C | 13 % | 33 km/h | 0.0 mm | Extreme 65 |
| 27 Sept | 35.4 °C | 11 % | 36 km/h | 0.0 mm | Very extreme 72 |
| 28 Sept | 36.5 °C | 10 % | 37 km/h | 0.0 mm | Very extreme 75 |
| 29 Sept | 37.3 °C | 11 % | 40 km/h | 0.0 mm | Very extreme 82 |
| 30 Sept after | 34.2 °C | 24 % | 58 km/h | 1.1 mm | Very extreme 95 |
Its twins: fires that started in the same weather
It started with an FWI of 54.0, a minimum humidity of 16% and more than two months without rain. Fires in the area that started in weather like this since 2016: 15.
FWI at the start
54.0
Minimum humidity
16 %
Days without rain
60+
this fire
chosen twins
rest of the area
Almost identicalSimilar
Outlines of the closest twins
This fire · Ghanzi fire, 18 September 2021
12,188 ha
12 days
FWI 54.0
Min. humidity 16 %
Ghanzi fire, September 2022
2,822 ha
5 days
FWI 53.5
Min. humidity 15 %
52 km away, in 2022
First rain (1 mm or more) after it ended: none in the following ten days.
Kweneng South fire, September 2018
4,484 ha
4 days
FWI 53.9
Min. humidity 16 %
114 km away, in 2018
First rain (1 mm or more) after it ended: none in the following ten days.
Kweneng South fire, September 2018
2,111 ha
4 days
FWI 52.4
Min. humidity 16 %
120 km away, in 2018
First rain (1 mm or more) after it ended: none in the following ten days.
Ghanzi fire, September 2023
16,956 ha
7 days
FWI 52.0
Min. humidity 14 %
21 km away, in 2023
First rain (1 mm or more) after it ended: none in the following ten days.
Hukunsti fire, August 2017
5,974 ha
6 days
FWI 53.5
Min. humidity 17 %
186 km away, in 2017
First rain (1 mm or more) after it ended: none in the following ten days.
What happened to them
- 4 days
- median duration
- 4,484 ha
- median area
- 7 %
- went past 10,000 ha
- —
- rain at the end (median; 0 of 15 had it)
It was 2.7 times larger than the median of its twins and lasted 12 days, against 4 days.
Only 1 of its 15 twins burned more. The weather on the first day does not explain everything: the wind in the following days, the fuel and the firefighting also count. In none of them did 1 mm fall in the ten days after the end: they all went out without rain.
This is a bank of analogues: it shows what usually happens, not what will happen. With fewer than 15 twins we give no figures. How we calculate it
How it ended
1.1 mmfirst rain
30 Septthe day after it ended
43km/h · max. gust
It was considered over on 29 Sept, and on 30 Sept 1.1 mm fell. We do not know whether the rain or the firefighters put it out. None of its 15 twins had rain when they ended.
Weather on this page: Open-Meteo.com (CC BY 4.0) · Copernicus Climate Change Service (ERA5)
How a twin is chosen
- Same area: fires that have already ended, less than 250 km from this one, since 2016.
- Same start: we compare the FWI on the first day, the minimum humidity that day and the run of days without rain before it. The slider sets how much they may differ.
- Only pages with final weather data (ERA5 reanalysis) calculated in the same way as this fire’s; agricultural and grass burns and pages with data under review are left out.
- Fires burning at the same time as this one (a week before or after) are left out: they share the same spell of weather and do not count as a precedent.
- They are sorted by similarity, and the outlines of the first five are drawn.
Before and after, from space
Drag the line to compare the same ground before the fire and after it.
↔
Before · 11 Sept 2021
After · 6 Oct 2021
Sentinel-2 did not pass over on that day. Try another date, or use false colour, which is daily.
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 · 439Every 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 time | Satellite | FRP (MW) | Lat | Lon |
|---|
Other fires nearby
Frequently asked questions
- How long did the Ghanzi fire last?
- According to the heat detections seen by satellite inside the perimeter, it burned from 18 September 2021 to 29 September 2021 (12 days). The perimeter dates it from 25 September 2021 to 29 September 2021.
- How much area did it burn?
- The perimeter GWIS (Copernicus) rebuilt from heat detections is 12,188 hectares (121.9 km²). It is an estimate: official national figures may differ.
- Which municipalities burned?
- The fire only entered Ghanzi (12,276 ha, 0.1 %).
- What was the weather like?
- During the fire the temperature reached 37.3 °C, humidity dropped to 7 % and gusts hit 43 km/h. The fire danger index (FWI) reached 82, class Very extreme.
- Where does this data come from?
- From the GWIS (Copernicus) burnt perimeter, NASA FIRMS VIIRS hotspots and the administrative boundaries of Botswana (geoBoundaries). It is not an official report.
- How did the fires that started in similar weather in this area end?
- Fires less than 250 km away that started since 2016 with a similar FWI, humidity and dry spell: 15. Their median duration was 4 days and their median area 4,484 ha; 7 % went past 10,000 ha. Only 1 of its 15 twins burned more. The weather on the first day does not explain everything: the wind in the following days, the fuel and the firefighting also count. In none of them did 1 mm fall in the ten days after the end: they all went out without rain.
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.
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.
- Start date: 25 September 2021 → 18 September 2021.
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
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 25 September 2021 to 29 September 2021. 439 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.
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 (Public Domain). 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.