Identification of peat-fire-burnt areas among other wildfires using the peat fire index

Abstract

Fires in peat soils are distinguished from other wildfires by their duration, the release of combustion pollutants dangerous to human health, carbon loss, and other environmental impacts. Peat fires can be detected by superimposing fire data extracted on the basis of the thermal anomalies of the MODIS Terra/Aqua Moderate Resolution Imaging spectroradiometer on previously developed peatland maps. It is necessary to take into account, not all forest fires in peatlands turn into underground (peat) fires. In the example of the extensive fires that occurred in Central European Russia in 2010, the potential of using fire activity indicators (fire radiative power (FRP), temperature, duration, etc., obtained according to MODIS data) to identify soil (peat) fires and separate them from surface fires was investigated. A special peat fire index (consisting of maximum values of FRP, average temperature, duration of burning, and area of ignition) was proposed and tested. A model of the peat fire index is a value that shows the degree of confidence that this fire is a peat fire. This index takes values from 0 to 1: 0 – surface fire, 1 – peat soil fire; values in the interval mean that a fire can affect both the surface and soil of the peatland. After analyzing the proportions of identified fires, we found out that the devised peat fire index is the most effective indicator compared with others. This indicator makes it possible to identify with high probability not only peat fires, but also to identify surface fires, and this reduces the area of uncertainty. Although the obtained results require verification at other sites, they provide convincing evidence that remote data can be used to detect peat fires.