The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences. Vol. XXXVII. Part B7. Beijing 2008 
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Figure 3-1 Chongqing NDVI on August 7 th , 2006 
Figure 3-2 Chongqing soil moisture on August 7 th , 2006 
Figure 3-3 Chongqing soil moisture on August 7th, 2006 
Figure 3-4 Meteorological Observation of Chongqing Drought 
in Summer of 2006 (July 21 st —August 10 th ) 
Figure 3-4 shows the drought distribution observed by 
Chongqing Municipality Climate Centre. 
Comparing the monitoring results from Chongqing Climate 
Centre with remote sensing retrieval results, we find that they 
are basically consistent. However, remote sensing retrieval 
result is more objective duo to its regional characteristic. It can 
be seen that political borders of counties are obvious in that of 
that meteorological observation data, because the 
meteorological observations are point data. Therefore, 
quantitative remote sensing retrieval soil moisture is more 
macro, objective, real-time in monitoring the actual local 
drought status. 
4. FOREST FIRE MONITORING IN CHONGQING 
4,1 Research Methods 
According to Wilhelm Wien's Displacement Law (Price J C, 
1983), MODIS bands 20, 21, 22 and 23 are designed for 
monitoring forest fire, which temperature is about 600 K and 
atmospheric window (8-14/jm) bands 31 and 32 are used to 
retrieval land surface temperature which temperature is about 
300 K. For the forest fire with smaller size, especially when 
forest fire area is smaller than that of a pixel, band 31 and band 
32 have important significance for the fire points monitoring. 
Furthermore, Channel 7 of MODIS has 500m spatial resolution. 
Our experiment showed that it is sensitive to high temperature, 
especially 600 ~ 1000K, though this channel has often been 
neglected in monitoring forest fires. We believe band 7 will 
greatly helpful for forest fire identification. 
Figure 4-1 and Figure 4-2 are brightness temperature of band 21 
and band 31 respectively. 
Figure 4-3 Brightness temperature of band 21 on August 11 th 
Figure 4-4 Brightness temperature of band 31 on August 11 th 
4.2 The Process and Results 
4.2.1 Direct Method for Detecting High Temperature 
Fire Points 
We use band 7 to detect high temperature fire points. Figure 4-3 
is the composite image of MODIS bands 7, 4 and 3. Figure 4-4 
is the enlarged one. The arrows point to two fire points. The left 
one is a high temperature open fire point. The right one is 
suspected a hidden fire point. According to reality information, 
at 12:00 on August 11 th , Bishan county, Aokang Industrial Park, 
Tiger hill occurred forest fire (fire should be 1). At 11:30 on 
August 11 th , Shapingba, Zengjia county occurred forest fire 
(fire should be 2). And this image’s acquisition time was 
August 11 th , MODIS (TERRA) crossing at local time 10:30, it 
was the very likely reason why lire point 2 has no smoke plume. 
In addition, some fires can also be found in Banan. 
Figure 4-3 RGB composite image of bands 7, 4, 3