Difference in observation of Indonesian fire by DMSP-OLS and NOAA-AVHRR
Mikiyasu Nakayama
Faculty of Agriculture, Utsunomiya University
350 mine-machi, Utsunomiya Tochigi 321-8505, Japan.
Tel: +81-28-649-5495 Fax: +81-28-649-5508
E-mail: nakauyama@utsunomiya-u.ac.jp
Abstract
Satellite remote sensing is a useful tool to monitor forest fire. While monitoring of forest fire has so far been performed mostly using one sensor. This study aims at developing a methodology with a view to identifying the progress of the forest fire to Indonesian using multiple sensors namely DMSP-OLS and NOAA-AVHRR. The study area was established in Sumatra Island. The period from 26 October to 7 November 1997 was chosen for this study. "Hot spots" were identified with NOAA-AVHRR nighttime imagery and "fire flares" with DMSP-OLS data. Both "hot spots" and "fire flares" detected were compared, so that relative advantage and disadvantages of two sensors may be evaluated. A number of forest fires were detected initially as "fire flares" by DMSP-OLS, much sooner than being detected as "hot spots" by NOAA-AVHRR. It was presumably because NOAA-AVHRR often fails to detect "hot spot" at the onset of a fire owing to haze. Some fires failed to be detected as "fire flares" by DMSP-OLS, while they were detected as "hot sports" by NOAA-AVHRR. It may be because NOAA-AVHRR detected forest fires as hot spots even in "smoldering phase" of forest fires.
Introduction
The forest fire in Indonesia has given many adverse impacts both on natural resources and humanity. Such harms were not only found within Indonesian. For example, slack in tourism by haze in Thailand and Malaysia has been observed in the
past. Decrease in tropical rain forest is a global environment threat. Monitoring of forest fire in Indonesia thus has utmost importance. Satellite remote sensing is a useful tool for this sake to cover the wide area. The monitoring of forest fire has been performed mostly using one sensor. However, in case of forest fire observed in Indonesia in 1997, it was difficult to identify the progress of fire under persistent cloud and haze only with a single sensor such as NOAA-AVHRR. The purpose of this study is to develop a "methodology with a view to identifying the progress of the forest fire in Indonesia using multiple sensors with different characteristics. As the first step for the sake, the imagery obtained by Operational Linescan System on the Defense Meteorological Satellite Program (DMSP-OLS) and by the NOAA-AVHRR were compared in order to find out both the advantages and disadvantages of these sensors.
Study area
The study area for fire detection was established in Sumatra Island within a box spanning the region from 1.9 to 2.5". S in latitude and 104.3 to 1.04.8° E. in longitude (figure 1). Indonesia is known the most 'cloudy' region in the world. The Sumatra Island was chosen for this study because cloud cover in this area was found less than other areas in Indonesia.
Figure 1 Study area
