Open Access

ARTICLE

Exploring the Dynamics of Terrestrial Water and Groundwater Storage across Nigeria: Insights from GRACE/GRACE-FO

Ikenna D. Arungwa^1,2,*, Elochukwu C. Moka²

1 Department of Surveying and Geoinformatics, School of Environmental Science, Federal University of Technology, Owerri, Nigeria
2 Department of Geoinformatics and Surveying, Faculty of Environmental Studies, University of Nigeria, Enugu Campus, Enugu, Nigeria

* Corresponding Author: Ikenna D. Arungwa. Email:

Revue Internationale de Géomatique 2026, 35, 423-459. https://doi.org/10.32604/rig.2026.083164

Received 30 March 2026; Accepted 08 June 2026; Issue published 29 July 2026

Abstract

This study utilized nearly two decades of temporal gravity field observations from the Gravity Recovery and Climate Experiment (GRACE/GRACE-FO) satellite missions to analyze the spatial and temporal variations of terrestrial water storage (TWS) and groundwater storage (GWS) in Nigeria. Advanced statistical techniques, including Singular Spectrum Analysis (SSA), Principal Component Analysis (PCA), and Empirical Orthogonal Function (EOF), were applied to characterize and quantify these variations at a basin scale. Results show that TWS exhibits biennial, annual seasonal fluctuations (between ±10 to ±55 mm), reaching its lowest levels during the dry season (February–June) and peaking in the wet season (August–October). Anomalously high TWS in 2012 coincided with one of Nigeria’s worst nationwide flooding events. Trend analysis reveals an overall increase in both TWS and GWS. While GWS oscillates annually and seasonally (±20 mm), it peaks between September and November and declines around May–June. Temporal decomposition reveals annual, inter-annual (3–4 years), and multi-annual (~10–12 years) cycles, suggesting influences from climate phenomena such as the El Niño-Southern Oscillation (ENSO) and Indian Ocean Dipole (IOD), along with human-induced factors like groundwater abstraction and land-use changes. The increasing trend in TWS and GWS implies enhanced aquifer recharge due to rising precipitation, but it also raises the risk of recurrent flooding. Notably, an out-of-phase pattern in the western littoral region suggests significant anthropogenic influence. This study highlights the value of GRACE-based monitoring for water resource management in Nigeria, particularly in regions where in-situ hydrological data are scarce.

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