OGINO Kazuhiko College of Agriculture, Ehime University, professor, 農学部, 教授 (90026394)
OGAWA Toshihiro Faculty of Science Department of Earth and Planetary Physice, University of Toky, 大学院理学部・地球惑星物理学科, 教授 (70011616)
YAMANAKA Manabu Radio Atmospheric Science Center, Kyoto University., Associate professor, 超高層電波研究センター, 助教授 (30183982)
The research activities have been performed as almost originally planned. The climatic and environmental aspects of the 1997 Indonesian forest fire event have been depicted by various measurements of meteorology, atmospheric optics, atmospheric chemistry, forest environmental studies in Indonesia and Singapore. Meteorological data analyzes have shown that there is a tendency that early onset of dry season causes delayd end of the dry season, and hence has a strong correlation with the magnitude of fires. It is also found, however, there is a large locality in meteorological condition for causing fires. For exapmle, there was a distinct seasonal change in rainfall amount in Java, whereas no such seasonal change was observed in Sumatra and Kalimantan regions. The total amount of emitted smoke particles is of order of 0.3 Tg/year, which is several times larger than that of past events in this region, and is equivalent to several percents of the total global emission due to agricultural activities. Since there were significant peat bog fires, a large amount of trees have fallen and cause smokes which are with less solar radiation absorption and with small particle radii as compared with those of Amazon and Africa. At the same time, the ozone amount has increased several times as compared with the standard value. Such a change in particulate and gaseous environment has caused a largeimpact on the energy budget and atmospheric stratification of this region. We need more analyzes to draw a final conclusion about the sign (cooling or heating) of the total effects of the forest fires.