| Central Northwest Territories |
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Natural Resources Canada > Earth Sciences Sector > Priorities > Canada Centre for Remote Sensing
Tour Canada from space Central Northwest Territories
 The summer of 1995 was an extremely harsh fire season in the Northwest Territories. This 750 x 750 km view from a NOAA satellite clearly shows several of the immense areas that were burning in mid-August. Other, higher resolution satellites with their smaller views (60 to 180 km across) would be incapable of covering such widespread burns (estimated here at 1.3 million hectares). You can identify burned areas on this image from the dark, mottled tones. Plumes of smoke can also be seen. Lakes, on the other hand are dark black and of a uniformly smooth texture. Great Slave Lake is at the bottom right and Great Bear Lake at the top centre. The largest northern-flowing river in North America, the Mackenzie, cuts diagonally through the image. Unburned vegetation is shown here in green, orange and red tones. Compare the fire progression of one affected area, over one month's time. The Mackenzie River acted as a natural fire-break for one large fire on the left side of the image.
Question: Which way is the wind blowing in this image? [ Answer ]
About this Image
| Location: |
Central Northwest Territories |
| NTS map(s): |
85, 86, 95, 96 (1:1M) |
 Location Map: |
See a detailed map (1:1M) of the region |
| Image Date: |
August 13, 1995 |
| Satellites/Sensors: |
NOAA Advanced Very High Resolution Radiometer (AVHRR), Channels 3,2,1 (R,G,B) |
| Resolution: |
1.1 km pixels |
| Image Area: |
Approximately 750 x 750 km |
| Image Features: |
Forest fire, smoke plume, sub-arctic, fire-break, tundra, resource management |
| Related Tour Images: |
Lac Nemiscau, Quebec |
| Related Glossary Terms: |
These terms from the CCRS Glossary may help you to understand this image and its interpretation:
change detection, colour composite |
| Related Tutorial Sections: |
These sections of the "Fundamentals of Remote Sensing" tutorial by CCRS will help you to better understand this image and its interpretation:
2.11 2.8 5.3.3
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| Image Credits: |
Received and processed by the Canada Centre for Remote Sensing
Provided courtesy of the NWT Remote Sensing Centre |
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Additional
Information: | The NWT Department of Renewable Resources relies on imagery like this to regularly map forest fire areas for the Forest Fire Management Division. Alternative methods would be impractical and too expensive. Such small scale imagery is ideal for frequently repeated views of the same area, since the NOAA satellite passes overhead once per day in the daytime. Three spectral channels of data were used from the NOAA satellite to create this composite image. Channel 1 is sensitive to light in the range of 0.58-0.68 micrometres (red light) and is shown in blue; channel 2, 0.725-1.1 micrometres (near infrared) and shown in green, and Channel 3, 3.55-3.93 micrometres (mid infrared) and shown in red. Combining these three channels in R,G,B creates the colour composite seen here. This type of colour composite usually represents water bodies in a very dark shade of red, however they have been deliberately changed to the black tone for this image. The Government of the NWT uses this type of imagery for a variety of purposes. It is used for identification of fires, measuring the extent of area burnt, assessing hotspots and areas requiring attention. Since the territory under their jurisdiction is so large, such analyses help them to assess fire risk, predict fire movement, and plan the allocation of their fire-fighting resources. Satellite imagery has also been known to show undiscovered fires. Although it may be difficult for "southerners" to believe, without this type of imagery, that large fires could burn completely unnoticed. |
| Question: |
Which way is the wind blowing in this image? |
| Answer: |
Using the smoke as an indicator of the wind direction, the wind is blowing in a northerly direction. |
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