Observational Evidence of Irrigation Influence on Vegetation Health and Land Surface Temperature in India

Irrigated area in India has significantly increased after the green revolution. However, quantification of irrigation influence on vegetation health and land surface temperature (LST) remains limited. Here, we develop a high-resolution (250 m) remotely sensed data of enhanced vegetation index (EVI) and LST from Moderate Resolution Imaging Spectroradiometer for 2000-2017 at the 8-day temporal resolution for India to quantify the role of irrigation in the modulation of EVI, LST, and vegetation health. We show that irrigation-dominated regions have significantly (p value < 0.05) higher EVI and cooler (1-2 K) LST during the crop-growing season in the Indo-Gangetic Plain. Vegetation health in highly irrigated areas is poorly correlated with meteorological drought primarily due to irrigation. Moreover, vegetation health is negatively correlated with groundwater storage anomalies in the highly irrigated Indo-Gangetic Plain. Irrigation in Indo-Gangetic Plain modulated EVI, LST, and vegetation health and resulted in groundwater depletion during 2002-2016.