Spectral mapping of an unregulated dump around Sofia municipality

Landfills are a source of heat and form their own thermal field, which is different from the natural thermal background of the environment, leading to the generation of thermal pollution, which is formed through the processes of biochemical decomposition of waste, and this in turn leads to the formation of local heat islands. Monitoring landfills (regulated or unregulated), their thermal pollution and dynamics by remote methods has a number of advantages that make these methods extremely effective. This is because remote sensing (RS) contributes to greater safety and accessibility for researchers, the observation of multiple parameters, much more effective monitoring of landfills, devoid of the subjective factors, easy detection of illegal landfills and greater efficiency. This type of monitoring contributes to the Assessment of the risk of natural disasters, control over the tracking of recycling and waste, reduction of financial costs for in-person monitoring and, last but not least, generation of a large database for climate analyses. This study presents a quasi-synchronous approach to spatial data analysis that can be used to locate and map unregulated dumps located within the Sofia Municipality. Various methods for visualization and interpretation of satellite data have been used. Composite images from the multispectral instrument (MSI) of the Sentinel 2 platform of the Copernicus program of the European Space Agency were used. The surface temperature of the landfill was calculated using the heat (THERMAL) bands from the Landsat as Landsat 8, Landsat 9 (OLI / TIRS) and Sentinel 3 SLSTR sensors. Data from different seasons and years were used in order to monitor the dynamics of thermal pollution in the study area. Assessment of the territory on which the unregulated dump located has been made. A positive correlation (r) between LST day (Sentinel -3LST) and LST (Landsat) has been proven with a value +0.99.