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

Abstract

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.

Modulation of Compound Extremes of Low Soil Moisture and High Vapor Pressure Deficit by Irrigation in India

“…(2009) also found a considerable role of irrigation on the increase in crop production across the globe. Irrigation results in healthy vegetation (Asoka & Mishra, 2015; Chen et al., 2019), land surface cooling (Ambika & Mishra, 2019; Mishra, Ambika, et al., 2020; Mishra, Thirumalai, et al., 2020), and reduces the atmospheric aridity (Ambika & Mishra, 2020; Shah et al., 2019). Overall, both satellite and reanalysis data sets reflect a potential role of irrigation on soil moisture, VPD, LST, and primary productivity over the Indo‐Gangetic plain region.…”

“…This considerable decline in the low soil moisture extremes over the Indo‐Gangetic plain and other regions can be partly attributed to irrigation as a decrease in the summer monsoon rainfall has been observed in the same region (Mishra et al., 2012; Roxy et al., 2015). Irrigation over the Indo‐Gangetic plain resulted in cooling and increased soil moisture (Ambika & Mishra, 2019, 2020; Mishra, Ambika, et al., 2020; Mishra, Thirumalai, et al., 2020). Atmospheric aerosols also cause cooling over the Indo‐Gangetic Plain (Kumar et al., 2017; Oldenborgh et al., 2018).…”

“…We obtained LST from National Oceanic and Atmospheric Administration (NOAA) Star Center for Satellite Application and Research (NSTAR), which is available at 4 km spatial resolution from 1982 to 2018 (https://www.star.nesdis.noaa.gov/star/index.php; Mishra, Ambika, et al., 2020; Mishra, Thirumalai, et al., 2020; Yu et al., 2017). LST represents skin temperature that can be used to understand the moisture stress (Ambika & Mishra, 2019). We obtained plant photosynthetic activity (Jonard et al., 2020) based on Solar‐induced chlorophyll fluorescence (SIF, Li & Xiao, 2019) for 2000–2016 (http://globalecology.unh.edu/data.html).…”

“…A massive expansion of 40 million hectares (mha) in the net irrigated area occurred between 1950 and 2008 (Ambika et al., 2016), which had profound impacts on groundwater abstraction, construction of reservoirs, and water and energy cycles (Asoka et al., 2017; Boucher et al., 2004; Shah et al., 2019; Yang et al., 2019). Previous studies identified a substantial imprint of irrigation on local climate, land surface temperature (LST), and atmospheric aridity (Ambika & Mishra, 2019; Shah et al., 2019; Thiery et al., 2020). For instance, a remarkable expansion in the irrigated areas resulted in cooling and influenced hot extremes (Cook et al., 2015; Siebert et al., 2013, 2015; Thiery et al., 2017).…”

A seven-fold rise in the probability of exceeding the observed hottest summer in India in a 2 °C warmer world

“…The global consensus for climate change mitigation is aimed at limiting global mean surface temperature rise to 1.5°C from the pre-industrial level by the end of the 21st century (UNFCCC 2015). However, the rise in the global mean surface temperature has almost breached the 1°C mark in 2018 and is likely to reach the 1.5°threshold by 2040 without strong mitigation efforts as highlighted in the Intergovernmental Panel on Climate Change's Special Report on Extreme Events (Allen et al 2018). Previous studies show that limiting the global mean temperature rise within 2°C is itself an enormous challenge, which requires sustained mitigation efforts and reliance on negative emissions in the long run (Peters et al 2012).…”