Smoke from widespread wildfires in Alberta, Canada travelled as far as parts of Europe and Russia in May and June 2019.
By Jochen Kerkmann (EUMETSAT), Ivan Smiljanic (SCISYS) and Sancha Lancaster (Pactum)
In Canada the official wildfires season starts on 1 March. So far, the 2019 season has been extreme, with the Ministry of Agriculture and Forestry reporting 656,842.84 hectares of land burned (up to 3 June), almost five times more than the five-year average. In total, from 1 March to 3 June, there were 558 fires reported.
By the end of May there were 29 wildfires still burning and reports on the extent of the smoke were starting to appear. By 30 May smoke had reached as far south as Denver, Colorado and had started to be seen on GOES-16 satellite imagery. By 31 May the smoke plume had reached Montana, North Dakota, South Dakota, Washington and Wyoming. Three cities in Montana had air quality warnings.
Next the smoke travelled eastwards across the Atlantic Ocean towards the UK and Europe. On the Meteosat-8 Natural Colour image from the evening of 3 June and the Meteosat-11 Natural Colour image from early morning on 4 June (Figure 1, top right, click to expand) the smoke can be seen embedded in deformation zones over Europe and Russia (bright cyan areas).
The majority of the smoke was transported over the Atlantic Ocean, embedded in the jet stream, at around 45 latitudes. However, some of the smoke reached Europe on 1 June, having, probably, been carried across in the higher latitudes. One such smoke band could be seen over Scandinavia on 1 June (Figure 2).
On 2 June, the smoke that was embedded in the jet stream merged with a low pressure system that passed the British Isles (Figure 3).
Forward scattering of small smoke particles is very strong in visible/solar bands, so smoke is best visible in early morning on Meteosat-11 images (Figure 4) and in the evening on Meteosat-8 images (Figure 3).
The smoke plume was still visible on Meteosat-8 24 hours later, at 18:00 on 4 June, (Figure 5), and also on the Meteosat-11 image, at 02:00 UTC on 5 June (Figure 6). By 5 June it was stretching from the Mediterranean Sea, across Italy, Germany and the Baltic Sea to Russia.
The full extent of the smoke on 4 June can be seen on two Meteosat-8 Natural Colour images from different times (18:00 and 24:00 UTC), which have been 'blended' together (Figure 7). Notice the sunglint appears on both sides of the image, due to the angles of view at the different times.
On 5 June, the smoke plume entered the Himawari-08 field of view, as can be seen over Central Asia in the 12:00 UTC (evening) Natural Colour RGB image (Figure 8).
It is interesting to note that in the Natural Colour RGB product the smoke casts more red shadows onto the underlying clouds. This is for the same reason as when skies take on impressive red shades during dusk, when there are smoke or dust particles in the air ('red sky at night'). Shorter wavelengths are scattered more by the smoke particles (green and blue components in this RGB, namely 0.8 um and 0.6 um, respectively), while more of the sunlight is transmitted through smoke at the wavelength of 1.6 um (the red RGB component).
Animation of multiday development of the smoke over Europe, seen by SEVIRI during the night hours (20:00–02:00 UTC, 30 May–7 June)
Canadian wildfire smoke over the Upper Midwest (CIMSS Blog)
Smoke from the Alberta wildfires is obscuring the sun in several U.S cities (Global News)
Smoke over the UK (Met Office/Twitter)
Alberta wildfire status (Ministry of Agriculture and Forestry)