Palazzoli et al. (2026) The hydrological asymmetric signature of El Niño–Southern Oscillation on global water storage

Identification

• Journal: Communications Earth & Environment
• Year: 2026
• Date: 2026-07-17
• Authors: Irene Palazzoli, Pierre Gentine
• DOI: 10.1038/s43247-026-03806-3

Research Groups

• Department of Civil, Chemical, Environmental, and Materials Engineering, Alma Mater Studiorum Università di Bologna, Italy (Irene Palazzoli)
• Department of Earth and Environmental Engineering, Columbia University, New York, USA (Pierre Gentine)

Short Summary

This study investigates the asymmetric impacts of El Niño–Southern Oscillation (ENSO) on global terrestrial water storage anomalies over the past four decades. The authors identify 81 El Niño-related clusters and 85 La Niña-related clusters covering 105.92 million km², showing that La Niña affects a broader area than El Niño.

Objective

• Investigate how ENSO phases have shaped global hydrological variability over the last four decades.
• Characterize the full spectrum of regional storage sensitivity to the complete ENSO lifecycle.

Study Configuration

• Spatial Scale: Global, with a focus on regions most responsive to ENSO forcing (excluding hyper-arid deserts and polar regions).
• Temporal Scale: 1984–2023, using a machine-learning reconstruction of water storage anomalies.

Methodology and Data

• Models used: GRAiCE dataset, a machine learning-based continuous reconstruction of global TWSA.
• Data sources: GRACE/GRACE-FO observations and independent water-budget datasets.

Main Results

• ENSO impacts 105.92 million km² of land, producing coherent wet and dry clusters across most climatic zones.
• La Niña exerts a broader control on global water storage than El Niño, affecting ~20% more land area.
• Dry responses dominate overall, but are most extensive during La Niña.

Contributions

• This study provides the first globally coherent assessment of ENSO-driven TWSA variability and asymmetry over an extended record.
• The framework introduced characterizes the full spectrum of regional storage sensitivity to the complete ENSO lifecycle.

Funding

• Not specified in the provided text.

Citation

@article{Palazzoli2026hydrological,
  author = {Palazzoli, Irene and Gentine, Pierre},
  title = {The hydrological asymmetric signature of El Niño–Southern Oscillation on global water storage},
  journal = {Communications Earth & Environment},
  year = {2026},
  doi = {10.1038/s43247-026-03806-3},
  url = {https://doi.org/10.1038/s43247-026-03806-3}
}