Wildfires in British Columbia

August 17th, 2018 |

GOES-16

GOES-16 “Red” Visible (0.64 µm, left) and Shortwave Infrared (3.9 µm, right) images [click to play MP4 animation]

A 2-panel comparison of GOES-16 (GOES-East) “Red” Visible (0.64 µm) and Shortwave Infrared (3.9 µm) images (above) showed the smoke plumes and thermal anomalies or “hot spots” (darker black to red pixels) associated with a flare-up of wildfires in western British Columbia on 17 August 2018.

A sequence of Shortwave Infrared (3.7 µm) images from Terra / Aqua MODIS and Suomi NPP / NOAA-20 VIIRS (below) revealed the diurnal changes in areal coverage and intensity of the thermal signature of the fires.

Shortwave Infrared (3.7 µm) images from Terra / Aqua MODIS and Suomi NPP / NOAA-20 VIIRS [click to enlarge]

Shortwave Infrared (3.7 µm) images from Terra / Aqua MODIS and Suomi NPP / NOAA-20 VIIRS [click to enlarge]

Toggles between Visible and Shortwave Infrared images from Terra MODIS (1912 UTC), NOAA-20 VIIRS (1950 UTC) ans Suomi NPP VIIRS (2129 UTC) are shown below (note: the NOAA-20 images are incorrectly labeled as Suomi NPP). It is interesting to note the impact that the smoke plume had on the air temperature at Quesnel (CYQZ) — because the smoke layer was optically dense enough (VIIRS True Color image) to significantly reduce incoming solar radiation, the temperature was as much as 14-18ºF (8-10ºC) cooler than Prince George (CYXS) to the north and Williams Lake (CYWL) to the south.

Terra MODIS Visible (0.65 µm) and Shortwave Infrared (3.7 µm) images [click to enlarge]

Terra MODIS Visible (0.65 µm) and Shortwave Infrared (3.7 µm) images at 1912 UTC [click to enlarge]

NOAA-20 VIIRS Visible (0.64 µm) and Shortwave Infrared (3.74 µm) images [click to enlarge]

NOAA-20 VIIRS Visible (0.64 µm) and Shortwave Infrared (3.74 µm) images at 1950 UTC [click to enlarge]

Suomi NPP VIIRS Visible (0.64 µm) and Shortwave Infrared (3.74 µm) images at 2129 UTC [click to enlarge]

Suomi NPP VIIRS Visible (0.64 µm) and Shortwave Infrared (3.74 µm) images at 2129 UTC [click to enlarge]

Farther to the east in Alberta, thick smoke caused very poor air quality in cities like Edmonton and Grande Prairie (photo 1 | photo 2). Daily composites of Suomi NPP VIIRS True Color RGB images from 11 August to 17 August (below) revealed the transport of smoke across British Columbia, Alberta and Saskatchewan.

Daily composites of Suomi NPP VIIRS True Color RGB images (with VIIRS fire detections in red), 11-17 August [click to play MP4 | Animated GIF]

Daily composites of Suomi NPP VIIRS True Color RGB images (with VIIRS fire detections in red), 11-17 August [click to play MP4 | Animated GIF]

A time series of surface reports from Edmonton, Alberta covering the period 14-17 August (below) showed that smoke restricted the surface visibility there to 1.5 miles on 15 August and 17 August.

Time series of surface reports from Edmonton, Alberta during the period 14-17 August [click to enlarge]

Time series of surface reports from Edmonton, Alberta during the period 14-17 August [click to enlarge]

===== 19 August Update =====

* GOES-17 images shown here are preliminary and non-operational *

GOES-17 Near-Infrared

GOES-17 Near-Infrared “Cloud Particle Size” (2.24 µm, left) and Shortwave Infrared (3.9 µm, right) images [click to play 81 Mbyte MP4 animation]

A 2-panel comparison of GOES-17 Near-Infrared “Cloud Particle Size” (2.24 µm) and Shortwave Infrared (3.9 µm) images during the 7-day period of 13-19 August (above) showed the diurnal changes in thermal signatures of the ongoing British Columbia wildfires. The nighttime thermal signatures seen on the 2.24 µm images (brighter white pixels) result from the fact that this spectral band is located close to the peak emitted radiance of very hot features such as active volcanoes or large fires (below).

Plots of Spectral Response Functions for ABI Bands 5, 6 and 7 [click to enlarge]

Plots of Spectral Response Functions for ABI Bands 5, 6 and 7 [click to enlarge]

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