Drought monitoring mapping by using satellite remote sensing: Study Case

Abstract

Drought is the consequence of the absence of water, and the many variables that produce the meteorological drought (as the reduction of precipitation, climate changes, and surface temperature between others) are well understood. When this Meteorological drought is persistent, it leads to a reduction of soil moisture or agricultural drought which consequently reduces the stream of rivers, lake levels, and underground flows creating a hydrological drought. In growing crops, the water deficit reduces the production efficiency of the enzymes in charge of the photosynthesis process of the plants which harms the farm’s production inducing a socioeconomic drought. European countries went through one of the most droughted periods of the last centuries during the summer of the year 2022 increased by the frequent heatwaves and Hungary was not exempted from its consequences, where the higher drought index is commonly observed in the northern, western, and central section of the country. In the study, satellite images were used to map the state of vegetation. We monitored the effect of drought on crop-growing soils based on the statistical analysis of vegetation indices calculated from images, where the Normalized Difference Vegetation Index (NDVI) values are notably increasing until the 21st of Jun of the year 2022 reaching a maximal value of 0,6012 in one of the analyzed fields before it starts decreasing to a minimum observed value of 0.3209 in the same field after a period of thirty-seven days due to lack of water.