{"slug": "reconstructing-grace-terrestrial-water-storage-with-spatio-temporal-graph-neural", "title": "Reconstructing GRACE Terrestrial Water Storage with Spatio-Temporal Graph Neural Networks: An Application to South America", "summary": "Researchers reconstructed GRACE-like terrestrial water storage anomalies back to 1940 using a spatio-temporal graph neural network (MTGNN) applied to South America. The model achieved high correlations and low bias, outperforming prior methods with fewer predictors, and is publicly available on GitHub.", "body_md": "arXiv:2606.23833v1 Announce Type: new\nAbstract: Terrestrial water storage (TWS) integrates snow, soil moisture, surface water, and groundwater and is a key indicator of how climate variability and human activity reshape the global water cycle. The GRACE and GRACE-FO satellite missions provide the only direct, globally consistent observations of TWS change, but their record only begins in 2002 which is too short for many climate-scale analyses. We present a deep learning application that reconstructs monthly GRACE-like TWS anomalies (TWSA) back to 1940 by learning the relationship between daily ERA5 meteorological forcing (precipitation, evapotranspiration, runoff) and monthly GRACE observations. In contrast to prior reconstruction approaches based on grid-cell-wise regression, CNNs, or LSTMs, we adapt a multi-variate time series graph neural network (MTGNN) architecture, which was originally developed for mobility and traffic forecasting on urban sensor networks to this satellite-geodesy task. Spatial dependencies are encoded in a static, interpretable hybrid adjacency matrix that combines geodesic proximity with lagged correlations of climatic time series, capturing both local hydrological coupling and large-scale teleconnections. The reconstruction achieves a grid-cell Pearson correlation of 0.69, a basin-mean correlation of 0.94, and a near-zero bias, and it reproduces the spatial fingerprints of the 2015/16 El Ni\\~no and 2020/21 La Ni\\~na events. A systematic comparison with established reconstruction approaches (GTWS-MLrec, RM-REC, GRAiCE) shows that the graph-based model is statistically competitive at basin scale, reaching a correlation within 0.025 of the best baseline while using only roughly half to a tenth of the predictors the other models require and revealing characteristic weaknesses in arid regions in all models. The complete implementation is publicly available at github.com/hcu-cml/MTGNN-TWS-Reconstruction-GRACE", "url": "https://wpnews.pro/news/reconstructing-grace-terrestrial-water-storage-with-spatio-temporal-graph-neural", "canonical_source": "https://arxiv.org/abs/2606.23833", "published_at": "2026-06-24 04:00:00+00:00", "updated_at": "2026-06-24 04:28:49.011058+00:00", "lang": "en", "topics": ["machine-learning", "neural-networks", "artificial-intelligence"], "entities": ["GRACE", "GRACE-FO", "MTGNN", "ERA5", "GTWS-MLrec", "RM-REC", "GRAiCE"], "alternates": {"html": "https://wpnews.pro/news/reconstructing-grace-terrestrial-water-storage-with-spatio-temporal-graph-neural", "markdown": "https://wpnews.pro/news/reconstructing-grace-terrestrial-water-storage-with-spatio-temporal-graph-neural.md", "text": "https://wpnews.pro/news/reconstructing-grace-terrestrial-water-storage-with-spatio-temporal-graph-neural.txt", "jsonld": "https://wpnews.pro/news/reconstructing-grace-terrestrial-water-storage-with-spatio-temporal-graph-neural.jsonld"}}