Exploring the use of satellite observations of soil moisture, solar-induced chlorophyll fluorescence and vegetation optical depth to monitor droughts across India

Abstract: The aim of this study is to explore the potential of remotely sensed soil moisture (SM), solar-induced chlorophyll fluorescence (SIF) and vegetation optical depth (VOD) to monitor droughts across India. Rainfall indicators such as standardised precipitation index and Z-score were used to identify deficit or normal rainfall events and it was compared with the Z-scores of the remotely sensed variables, using correlation and time-series analysis. The results indicated that SM was able to capture drought events throughout India and across all land covers. Similarly, SIF and VOD could also capture drought signals but with a certain lag after precipitation, except for over irrigated croplands. Among the different microwave frequencies such as L-, C- and X-bands, VOD-X exhibited strong correlation with rainfall indicators. All the three variables have the potential to capture drought events and hence should be included in operational drought monitoring programmes in India. Research highlights: Managed Aquifer Recharge sites in the fluoride contaminated aquifer were delineated.A total of 41 artificial recharge sites were delineated, among them only 13 sites considered as suitable for implementation of MAR structures.Showed the importance of chemical behaviour of groundwater during the recharge.Behaviour of fluoride with water level fluctuation was used as a key factor.