Ground Water Level and Precipitation Pattern for Indonesian Peat Fire Risk Assessment

Peat fires Indonesia are primarily a function of severe drought due to long dry seasons and less precipitation during El Nino events, among others. Drought leads to decreasing groundwater levels and exacerbates burning conditions. Our previous study revealed the close relationships among precipitation, groundwater level, and peat fire. To get a better understanding of this issue, we studied fire conditions in a portion of the ex-Mega Rice Project (MRP) area, Central Kalimantan. Here, we examine fire season and hydrology factors affecting peat fires by using 18-years of daily precipitation data from the TRMM satellite (2000-2017), 16-years of daily MODIS hotspot data (2002-2017), Nino 3.4 SST Anomalies, and 8-years of changing groundwater level data (2010-2017) from 300 dipwells, established in the MRP area, to explain precipitation patterns influencing the occurrence of peat fires. Our results powerfully illustrate that the long dry season followed by a relatively dry-rainy season will drive high intensity peat fires in the coming year, providing a country with some ability to predict fire risk in advance. Thus, rainfall patterns of the previous successive dry and rainy seasons should be taken into consideration when implementing peat fire prevention measures. Recently, the Government of Indonesia indicated a groundwater level threshold of -40 cm below the peat surface as a threshold for preventing surface fires from igniting the peat. However, our results strongly indicate that a groundwater level threshold of -20 cm is necessary in areas of degraded peat to prevent ignition of peat fires.