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This hotspot detection archive started in February 2002. The metadata for each hotspot detection file has the following format:
| s-o FEB 12 21:23 2002 WST |
Large map |
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Area : area |
Small map |
| Method : method |
Satellite map |
where :
- s is the satellite (either Terra or Aqua),
- o is the satellite number,
- area is the area (state) that the hotspots lie within and
- method is the method used to detect the hotspots and is either manual or automatic.
- Large map shows the fires as red crosses, possible fires as green crosses and clouds/sea as grey for that area (state). If there are parts of the map where there was no useable data this is grey as well. The passes that occur at dusk and dawn tend not to have large amounts of useable data because of the amount of sunlight. Users with Netscape Navigator V4.0 or above can hold down the left mouse button and the latitude/longitude will appear in the status bar at the bottom of the browser.
- Small map shows the same as the large map but is much smaller in size. This allows the user to quickly see if there are any hotspots in their area of interest and whether to download the large map.
- Satellite map shows the same small map but is clickable and then retrieves the satellite image (actually MODIS band 32 brightness temperatures). This allows the user to check whether the possible fires are actually cloud edges. Users with Netscape Navigator V4.0 or above can hold down the left mouse button and the latitude/longitude will appear in the status bar at the bottom of the browser.
The automatic fire detection using Terra-MODIS data started on February 12 2002. Terra-Aqua data was added on August 8 2002. Currently there is no manual fire detection using Terra-MODIS data. All hotspot locations are in geographical degrees minutes format. On some days up to four MODIS passes are used to detect hotspots. With the automatic method not all hotspots detected are fires. There are certain hotspots that are detected at approximately the same location every so often. Some of these are :
| State |
Description |
Latitude |
Longitude |
| WA |
Gas Flares |
20°37' S |
116°46' E |
| WA |
Gas Pits |
21°28' S |
115°01' E |
| WA |
Nickel refinery |
30°52' S |
121°29' E |
| WA |
Alumina refinery |
32°52' S |
116°04' E |
| SA |
Blast furnace |
33°01' S |
137°34' E |
| SA |
Olympic Dam |
30°27' S |
136°53' E |
| SA |
Gas and oil fields |
28°07' S |
140°13' E |
| QLD |
Copper smelter |
20°43' S |
139°28' E |
Because the automatic rectification of the image is not as good as the manual method the co-ordinates listed in the automatic method can be in error by up to 2 minutes in either latitude or longitude. The difference between the known location (listed above) and the detected hotspot gives an idea of the error in that region.
The manual method (human operator) provides greater accuracy however it takes longer.
Since 13 March 2002 the hotspot locations can be downloaded and viewed in ArcView by clicking on ArcView version at the top of each page containing the list of fires. To view fire hotspot information in ArcView prior to this follow these instructions.
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