TITLE:
Spatiotemporal Analysis of Groundwater Storage Dynamics across the Major Aquifer Systems in Nigeria Using GLDAS Data
AUTHORS:
Peter Adetokunbo, Ayodeji Adekunle Eluyemi, Michael Ayuk Ayuk, Rasheed Babatunde Adesina, Segun Aguda, Olayiwola Grace Olaseeni, Joel Olayide Amosun
KEYWORDS:
GLDAS, Groundwater, Nigeria, Hydrogeology
JOURNAL NAME:
Open Access Library Journal,
Vol.12 No.7,
July
29,
2025
ABSTRACT: The spatial variability of groundwater storage in Nigeria was investigated using Global Land Data Assimilation System (GLDAS) data over 21 years (2003 and 2023). The spatial and temporal analyses of the data were conducted in Google Earth Engine (GEE) and Python to assess regional and national aquifer responses to environmental change. The time analysis of the data revealed high groundwater recharge rates from 1.2 mm/year (2003-2013) to 14.5 mm/year (2013-2023). Three hydrogeological regions were identified that closely match the major aquifer systems in Nigeria: the extremely high groundwater storage (2500 - 3400 mm) of the Niger Delta Basin, the intermediate values (2000 - 2500 mm) of the Middle Belt region (Middle Niger Basin/Benue Trough), and low values (300 - 1500 mm) in Northern Nigeria (principally Basement Complex/Chad Basin). One major transition zone occurred in southwest Nigeria where the groundwater storage indicated a well-defined gradient of the transition from unconsolidated coastal aquifers at Lagos/Ogun to basement complex rocks at Ondo. The time lapse difference map revealed major regional contrast with a sharp increase (80% - 100%) in northeast Nigeria (Chad Basin) and moderate decrease (1% - 20%) in southern regions. The findings show the differential behavior of aquifer systems in Nigeria and their response to the diverse climatic changes and anthropogenic stresses which have implications for regional water resource planning.