Over the several years, there have been major forest fires in Australia, the Amazon in Brazil and California in US. We consider global warming as the cause of forest fires. However, the frequency of forest fires due to spontaneous combination is low. The progress of global warming is a problem because large-scale forest fires reduce the area of forests that purify the air.

   In Japan as well, there was a series of news reports on forest fires, and we have the impression that the number of cases is increasing. However, in 1975 and has been declining. Forest fires are man-made disasters caused by    bonfires and mismanagement of fires, and are not caused by global warming.