Monthly and Seasonal Drought Characterization Using GRACE-Based Groundwater Drought Index and Its Link to Teleconnections across South Indian River Basins

Kuruva Satish Kumar,Pallakury Anandraj,Koppala Sreelatha,Deepak Singh Bisht,Venkataramana Sridhar

doi:10.3390/cli9040056

Abstract

Traditional drought monitoring is based on observed data from both meteorological and hydrological stations. Due to the scarcity of station observation data, it is difficult to obtain accurate drought distribution characteristics, and also tedious to replicate the large-scale information of drought. Thus, Gravity Recovery and Climate Experiment (GRACE) data are utilized in monitoring and characterizing regional droughts where ground station data is limited. In this study, we analyzed and assessed the drought characteristics utilizing the GRACE Groundwater Drought Index (GGDI) over four major river basins in India during the period of 2003–2016. The spatial distribution, temporal evolution of drought, and trend characteristics were analyzed using GGDI. Then, the relationship between GGDI and climate factors were evaluated by the method of wavelet coherence. The results indicate the following points: GRACE’s quantitative results were consistent and robust for drought assessment; out of the four basins, severe drought was noticed in the Cauvery river basin between 2012 and 2015, with severity of −27 and duration of 42 months; other than Godavari river basin, the remaining three basins displayed significant negative trends at monthly and seasonal scales; the wavelet coherence method revealed that climate factors had a substantial effect on GGDI, and the impact of Southern Oscillation Index (SOI) on drought was significantly high, followed by Sea Surface Temperature (SST) Index (namely, NINO3.4) and Multivariate El Niño–Southern Oscillation Index (MEI) in all the basins. This study provides reliable and robust quantitative result of GRACE water storage variations that shares new insights for further drought investigation.

Highlights

Introduction published maps and institutional affilDrought is a dynamic natural phenomenon with high frequency and long duration characteristics that impact ecosystems and society in many ways [1,2,3]
Seasonal and annual scale Gravity Recovery and Climate Experiment (GRACE) terrestrial water storage anomaly (TWSA) analysis was performed over four basins
The results showed distinct seasonal and annual TWSA characteristics over these river basins

Summary

Introduction

Drought is a dynamic natural phenomenon with high frequency and long duration characteristics that impact ecosystems and society in many ways [1,2,3]. Drought is a common natural disaster that has serious influence on water resources, agriculture, and socio-economic development due to its long-term persistence and frequent occurrence [4,5,6]. Monitoring of traditional drought depends on ground data from meteorological and hydrological stations. Due to the scarcity of station observation data and the spatial heterogeneity of the regional environment, it is difficult to obtain accurate drought distribution characteristics, and tough to replicate the large-scale information of drought [7]. To precisely monitor and assess drought characteristics, researchers have developed various drought indices such as the Palmer Drought Severity Index (PDSI) [8], Standardized Precipitation Index (SPI) [9], Standardized Precipitation Evapotranspiration Index iations

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Conclusion