Historical climatic time series analysis of ENSO influence on surface and groundwater levels in Central Mexico

The historical climatic data provide valuable information to understand the groundwater behavior. When groundwater and surface data levels are combined with climatic records, the water levels present the influence of El Niño–Southern Oscillation. However, there is no comprehensive record of surface and groundwater levels in Mexico, which limits this focus. This is the first study to evaluate the influence of the ENSO on hydrogeological dynamics in a groundwater flow system (GFS) placed in Central Mexico. The methodology consisted of compiling groundwater and surface water levels from multiple sources and data sets of historical time series of precipitation, runoff, and spatial/temporal variability patterns across different ENSO phases. The main results indicate that precipitation and surface runoff exhibit a strong response to El Niño and La Niña events, resulting in distinct hydrological anomalies that impact the recharge and discharge dynamics of the basin. Indicators show decreases in precipitation and groundwater levels during El Niño events, and increases in precipitation and surface water levels during La Niña events.

Multidecadal trends indicate that land use and vegetation changes significantly modify the hydrological response to ENSO by intensifying evapotranspiration, altering infiltration rates, and affecting the interaction between groundwater and surface water. These analyses allow us to understand the complex relationship between historical climate data and water levels, linked to natural processes and anthropogenic processes, especially those associated with water extraction. 

This study provides an example for evaluating climate and hydrological changes linked to anthropogenic activities to improve sustainable management of water resources.