Concept of fire location data
To strengthen the prevention of air pollution, the MOENV cooperates with the Central Weather Administration and applies satellite remote sensing technology to enhance environmental monitoring ability. By receiving real-time observation data from the satellite, fire locations can be mapped (as shown in Figure 1). It can help strengthen non-traditional abilities in pollution monitoring and control, including analyzing hotspots of trash burning, monitoring agricultural waste biomass burning, and inspecting abnormalities in flares of fixed air pollution sources. The data is provided to local environmental protection departments and can increase the efficiency in auditing and law enforcement.
Currently, the MOENV's fire location data mainly comes from Terra, Aqua and Suomi NPP, the 3 polar-orbiting satellites of Central Weather Administration. The first 2 are equipped with moderate resolution imaging spectroradiometer (MODIS) and the 3rd one is equipped with visible infrared imaging radiometer suite (VIIRS). They are constantly circling around the earth by an almost North-South axis everyday to conduct observation (as shown in Figure 2).
Theories of fire location
The analysis of fire location data is done mainly by making use of the multispectral sensor equipped on the satellites. After analyzing middle-infrared and thermal infrared spectrums, the MOENV can evaluate which area on the ground has higher temperature and calculate reasonable coordinates and the brightness temperature (as shown in Figure 3). After the analysis, the MOENV can immediately provide when and where (including coordinates, township, county, or city) a place becomes a fire location, along with brightness temperature and radiant power of the fire location, to local environmental protection departments through emails. For more detailed theories, please refer to the web-page of NASA Fire Information for Resource Management System (FRIMS).
Fire location FAQ
Q ：I can see that there is a tremendous amount of open burning in my neighborhood, but why can’t I see any fire location on the system?
Because the sensors that are used now cover middle-infrared and thermal infrared spectrums, and the results can easily be affected by clouds. So if a cloud happens to pass by above a fire location, the system might not be able to identify the fire location.
Q ： I can see open burning from my house, but why is its location different from that on the system?
Because the maximum deviation of the sensor equipped on the satellite now is around 1 kilometer, so the fire location might be slightly erroneous.