Asia Pacific Network for Disaster Mitigation Using Earth Observation Satellite(Andes)(1)- Forest Fire Detection
4. Forest Fire Detecting in East Asia
In the Southeast Asian region, wild fire and artificially made fire for farming sometimes became large
and uncontrollable, and damaged human activities and health. Information for such fire is needed as soon
as possible. NOAA/AVHRR data is useful for fire detecting because NOAA POES frequently and widely
observe ground. The data is processed and thermal spots which are possible fire are detected in our
system.NOAA/AVHRR HRPT data received at Asian Institute of Technology (AIT), Thailand, covering this
region is transferred in real time to the computer center of Agriculture,
Figure 2. Images of big fire monitored by 2 earth observation
satellites in Riau province in Sumatra, Indonesia, July 13, 2000.
(a) Legends and index map.
(b) Distributions of burnt
area, smoke and haze cause by big fire recognized by using SPOT image. Some burnt areas eject smoke and they still burns or smolders. The other areas are already ceased eject smoke and they are hot but does not burn. Smokes spread forward NNE direction and this shows wind direction. Right half are covered with haze which may be produced another areas in Sumatra.
(c) Distributions of thermal spots detected by the ANDES system. Most of all areas which eject smoke (in picture b and meaning "burns") are detected as thermal spots.
Forestry and Fisheries research in Tsukuba through highly advanced network links
(Science Information Network (SINET) and IM-net). Shiogama, Yokohama and Ishigaki stations in
Japan receive NOAA/AVHRR HRPT data and send through MAFFIN network to the computer center. These
data covering most of East and Southeast Asian countries, are processed by the real time fire detecting
system. Mainly nighttime data is used for detecting thermal spots, because channel 3 data of AVHRR is
not affected by day light, cloud and heated surface by the sun directly. This system uses simple
threshold as "T3 > 310K" for detecting thermal spots and this was verified by comparing with
high-resolution images of SPOT satellite (Figure 2). AIT data just covers Indonesia, in which haze
sometimes caused by big fire and damages closing area. Although this area is often covered with noises
which are made at the beginning of receiving and these makes pseudo thermal spots, they are removed by
geometrical method in the system.
In the system, both thermal spots of NOAA/AVHRR and fire products of DMSP/OLS data are showed with
SPOT/vegetation ten-day's composite using LMF method (Sawada, 1999). Thermal spots sometimes include
remanent noises and show heated point which has remanent heat of sun light. DMSP/OLS detects only light
and this supports AVHRR thermal spots data for separating these pseudo thermal spots. Real time fire
products process three kinds of satellites data and the final images are put on the ANDES web site
early next morning. Real time fire detecting system does not only detect thermal spots but also checks
time-series of the spots. When a thermal spot is detected on a same place (accuracy is about 1km),
the system records and informs by email where and how long the continuous spot exists. Because
continuous thermal spots mean big or uncontrolled fire. In fact, in July 2000, in Sumatra
, Indonesia, number of detected thermal spots rapidly increased, and many spots continued (5 days
in maximum). As shown in figure 2, the area where continuous thermal spots sited, spots distributes
as cluster and it consists of more than ten spots, and big fires occurred and they made haze and
smokes over several ten kilo meters. On the contrary, in March 2000, in and around Thailand, the
number of thermal spots reached maximum. But almost all thermal spots disappeared within a day, and
they distributes separately. This means fires in this region were almost controlled and they did not
grew dangerous fires.
References
Sawada, Y., Mitsuzuka, N., Sawada, H., 1999. Classification of vegetation types by time series data
analysis of vegetation index. Proceedings of the 27th conference of Remote Sensing Society of Japan,
pp.73-74.
