Unusually hot and dry mid-August conditions beneath a strong ridge of high pressure across British Columbia led to a major outbreak of wildfires across that western Canadian province — 1-km resolution GOES-15 0.63 Âµm visible channel images (above) showed the development of a number of large and very dense smoke plumes late in the day on 14 August 2010. A veil of smoke aloft from the previous day of fire activity could also be seen drifting southwestward across the adjacent offshore waters of the Pacific Ocean.
The corresponding 4-km resolution GOES-15 3.9 Âµm shortwave IR images (below) revealed numerous fire “hot spots” (black to red pixels) across the region. The hottest fire pixels exhibited IR brightness temperatures of 338 K. Note how the number and intensity of the fire hot spots diminished after sunset. The large arc of very hot IR brightness temperatures seen over the Pacific Ocean at the Earth’s edge was due to sun glint.
The comparison of a 1-km resolution NOAA-16 AVHRR Red/Green/Blue (RGB) image (created using AVHRR channels 1/2/4) with the corresponding AVHRR 3.7 Âµm shortwave IR image (below) revealed that a a few of the fire hot spots were easily detected even though they were beneath very thick smoke plumes.
A comparison of a 4-km resolution GOES-15 3.9 Âµm shortwave IR image with the corresponding 1-km resolution NOAA-16 3.7 Âµm shortwave IR image (below) demonstrated the value of higher spatial resolution for helping to more accurately identify the exact location of even the smaller active fire pixels; on one of the largest fires located near the center of the image, it can be more clearly determined that a ring of active fires was burning around a core of spent fuels. In addition, the northwestward “parallax shift” was evident due to the large viewing angle of the GOES-15 satellite (positioned at a longitude of 89.5Âº over the Equator).