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Alter do Chão fire, August 2016 Seda, União das Freguesias de Ponte de Sor, Tramaga e Vale de Açor, Chancelaria

Out · last detection 9 Aug 2016, 14:38 UTC

The fire started on 9 August 2016 in Seda, Portugal, and satellites saw it burning for 1 day. Copernicus mapped a burnt perimeter of 724 hectares from satellite imagery, spread across 4 municipalities. According to ICNF, it was detected on 9 August 2016 at 15:07 and declared extinguished on 9 August 2016.

Number 45 in Portugal in 2016, of 179.

Burnt area
724ha
Copernicus perimeter
Duration
1day
9 Aug 2016 – 9 Aug 2016
Municipalities hit
4
freguesias
Started on
9 Aug
2016
Heat detections
5
in a single hotspot: 72 MW
Danger at start
65
Extreme · FWI index
Energy released
283MW
sum of detected power

Where it burned

HOTSPOTS BY DAY 9 Aug9 Aug

How it evolved, day by day

9

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
48km/h · peak gust
15%lowest humidity

It had gone 32 days without rain (1 mm or more) when it started.

This area had burned before

No earlier perimeters overlap this fire since 2016, when the satellite record begins.

What happened to each town

  1. Seda 355 inhabitants · 3.7 km from the town where it started
    670 ha reached on 9 Aug
    5.9 %
  2. União das Freguesias de Ponte de Sor, Tramaga e Vale de Açor 698 inhabitants · 7.6 km from the town
    39 ha reached on 9 Aug
    0.1 %
  3. Chancelaria 4.0 km from the town
    12 ha
    0.2 %
  4. Benavila e Valongo 878 inhabitants · 6.3 km from the town
    5 ha
    0.0 %

Burnt area inside each municipality, from crossing the official perimeter with administrative boundaries. The distance is from the town centre to the nearest fire: staying a kilometre away does not mean it reached the houses.

What burned

  • Agricultural areas82 %
  • Scrub and transitional woodland15 %
  • Other land cover3.2 %

Natura 2000 protected area affected: 60 %

Natura 2000 sites (European Environment Agency, 2024 release) crossed by the perimeter.

Land cover inside the perimeter according to Corine Land Cover, as reported by Copernicus.

Official record

According to ICNF, this fire started on 9 August 2016 and burned 700 ha (the satellite measured 724 ha).

ICNF (Instituto da Conservação da Natureza e das Florestas). This is the agency’s operational record: its figures may be revised when the year’s statistics are closed.

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)
9 Aug 38.0 °C 15 % 48 km/h 0.0 mm Extreme 65
10 Aug after 34.2 °C 26 % 48 km/h 0.0 mm Extreme 55
11 Aug after 35.2 °C 25 % 38 km/h 0.0 mm Very high 50
12 Aug after 36.7 °C 16 % 26 km/h 0.0 mm Very high 46
13 Aug after 36.9 °C 20 % 30 km/h 0.0 mm Very high 48
14 Aug after 36.0 °C 23 % 35 km/h 0.0 mm Extreme 50
15 Aug after 32.6 °C 29 % 33 km/h 0.0 mm Very high 43
16 Aug after 30.0 °C 27 % 35 km/h 0.0 mm Very high 43
17 Aug after 30.8 °C 37 % 42 km/h 0.0 mm Very high 39
18 Aug after 32.3 °C 26 % 36 km/h 0.0 mm Very high 40
19 Aug after 27.6 °C 49 % 35 km/h 0.0 mm High 30

Before and after, from space

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

Before · 2 Aug 2016
After · 16 Aug 2016

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 9 August 2016 the air beside the fire reached 63 µg/m³ of PM2.5. That day averaged 33: 2.2 times the WHO daily guideline (15).

PM2.5 peak63 µg/m³
Days over the guideline1 day
PM1075 µg/m³
789101112
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 · 5Every 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 Portugal ›

Frequently asked questions

How long did the Alter do Chão fire last?
Copernicus dates it between 9 August 2016 and 9 August 2016: 1 day between the first and last image with fire. According to ICNF, it was detected on 9 August 2016 at 15:07 and declared extinguished on 9 August 2016.
How much area did it burn?
The perimeter Copernicus measured from satellite imagery is 724 hectares (7.2 km²). Official national figures may differ.
Which municipalities burned?
The fire entered 4 municipalities: Seda (670 ha, 5.9 %); União das Freguesias de Ponte de Sor, Tramaga e Vale de Açor (39 ha, 0.1 %); Chancelaria (12 ha, 0.2 %); Benavila e Valongo (5 ha, 0.0 %).
Did the fire reach a town?
The closest fire to a town centre came within 3.7 km of Seda. That is the distance to the perimeter or nearest hotspot; it does not mean it entered the houses.
What was the weather like?
During the fire the temperature reached 38.0 °C, humidity dropped to 15 % and gusts hit 48 km/h. The fire danger index (FWI) reached 65, class Extreme.
Where does this data come from?
From the EFFIS (Copernicus) burnt perimeter, NASA FIRMS VIIRS hotspots and the administrative boundaries of Portugal (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

Satellite cross-check

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.

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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.

Where this data comes from

The perimeter and land cover come from the Copernicus European Forest Fire Information System (EFFIS), measured on MODIS and Sentinel-2 imagery and published under CC BY 4.0. 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 ADM3 (CC0 1.0 Universal (CC0 1.0) Public Domain Dedication). The area per municipality is computed by WorldFires by crossing the perimeter with those boundaries, so it may differ slightly from each country’s official figure.