Inaccuracy of hotspots data for early warning land fires incidence

Abstract

Severe and expansive land fires in Indonesia have been occurred since 1982 due to the human activities and got more severe because of El Nino phenomenon. The impact of this catastrophe has always been notorious. The land fires in 2019 burned down a total of 850,000 hectares of which 200,000 hectares were peat land. The National Disaster Mitigation Agency (BNPB) stated that 85% of the land fires incidence did not occur in concession land, on the contrary, The Ministry of Environment and Forestry claimed that 85% of the land fires were related to oil palm plantation or oil palm businesses. These contradictory statements of both government institutions have led to the public's bafflement, therefore the aim of this study was to seek the actual condition regarding the land fires in 2019. The results show that the BNPB statement was based on satellite data and actual field observation data while extinguishing the fires. Meanwhile, The Ministry of Environment and Forestry released their statement according to the land fires hotspots data. This research showed that there are many land fires cases actually detected from real time burn scar of Sentinel L1C and L2A, but are not detected from the MODIS C6 hotspots data. This fact related to the fire flow that fire was initiated mostly in areas with low biomass vegetation such as shrubs. This type of vegetation provided highly combustible fuel for fires so that fire continuously swept the whole similar areas and eventually approached areas with higher biomass vegetation, such as oil palm plantation. Once fire reaches and burns higher biomass vegetation, it lasts for a longer period, and will be recorded as hotspots data. Referring to the regulation of The Ministry of Environment and Forestry Number P.8/MENLHK / General Secretariat / KUM.1 / 3 / 2018 article 8, land fires without hotspots recorded will not be the priority to be checked and controlled. Consequently, the fire will be only detected and then checked after reaching the area with higher biomass vegetation, such as oil palm plantation. There will be a significant delay for inspecting and controlling initial fires. This study also showed that as the result of this monitoring system, The Ministry of Environment and Forestry tended to assume that the land fires are mostly initiated and occurred on oil palm plantations or on concession areas. Therefore it can be concluded that hotspots data cannot be the only source for early warning land fires incidence. An alternative method which is more accurate and susceptive should be invented.