Liaqat et al. (2026) Beyond GRACE: Evaluating the benefits of NGGM and MAGIC for precipitation estimation over Europe

Identification

• Journal: Hydrology and earth system sciences
• Year: 2026
• Date: 2026-08-07
• Authors: Muhammad Usman Liaqat, Stefania Camici, Francesco Leopardi, Jaime Gaona, Luca Brocca
• DOI: 10.5194/hess-30-4969-2026

Research Groups

• Institute of Geosciences, National Research Council, Italy
• Department of Civil and Environmental Engineering, University of Perugia, Italy

Short Summary

This study evaluates the benefits of Next Generation Gravity Mission (NGGM) and Mass Change And Geosciences International Constellation (MAGIC) for precipitation estimation over Europe. The results show that SM2RAIN algorithm exhibits satisfactory performance at a daily temporal resolution, with a mean correlation coefficient of 0.86.

Objective

• To examine the impact of improved accuracy and spatiotemporal resolution of NGGM and MAGIC on precipitation estimation using the SM2RAIN algorithm.
• To investigate the sensitivity of precipitation retrieval to different synthetic mission configurations by adding Gaussian error into simulated TWS observations used as input to the SM2RAIN algorithm.

Study Configuration

• Spatial Scale: Europe, with a spatial grid corresponding to the ERA5L dataset resampled to approximately 100 km spatial resolution.
• Temporal Scale: Daily to weekly scales, with a focus on sub-weekly temporal sampling and effective spatial resolution approaching approximately 100 km at regional scales.

Methodology and Data

• Models used: SM2RAIN algorithm, which estimates precipitation accumulated between two consecutive TWS measurements by inverting the soil water balance equation.
• Data sources: ERA5-Land reanalysis product, which provides volumetric soil moisture content and total precipitation data from 1950 to present.

Main Results

• The results show that SM2RAIN exhibited satisfactory performance at a daily temporal resolution, with a mean correlation coefficient of 0.86.
• The study found that the NGGM/MAGIC mission configurations exhibit good agreement with the reference precipitation data, with mean R, RMSE, and bias values of 0.95, 9.45, and −0.21 mm, respectively.

Contributions

• This study provides a comprehensive evaluation of the benefits of NGGM and MAGIC for precipitation estimation over Europe.
• The results highlight the potential value of next generation gravity missions such as NGGM and MAGIC, whose improved temporal resolution and measurement accuracy are expected to enhance the detectability of short-term storage changes and improve precipitation estimation.

Funding

• This research was funded by the European Space Agency (ESA) under the Future EO Program.
• The study also received funding from the National Aeronautics and Space Administration (NASA) for the development of the NGGM mission.

Citation

@article{Liaqat2026Beyond,
  author = {Liaqat, Muhammad Usman and Camici, Stefania and Leopardi, Francesco and Gaona, Jaime and Brocca, Luca},
  title = {Beyond GRACE: Evaluating the benefits of NGGM and MAGIC for precipitation estimation over Europe},
  journal = {Hydrology and earth system sciences},
  year = {2026},
  doi = {10.5194/hess-30-4969-2026},
  url = {https://doi.org/10.5194/hess-30-4969-2026}
}