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Central and Southern Europe is undergoing a drying trend driven by increased evapotranspiration and rising air temperatures, even though precipitation levels remain stable. In the Bug River Basin, GRACE observations indicate that total water storage (TWS) declined at a rate of 8.8 ± 5.2 mm/year between 2012 and 2023. To validate this trend, we analysed spatial and temporal discrepancies between TWS-GRACE and water budget-based estimates (TWS-WB). Using ensemble data assimilation techniques, we integrated hydrometeorological data with TWS-GRACE. Regression models developed for TWS simulation were employed to adjust TWS-GRACE estimates. The results demonstrate that TWS fusion effectively mitigates uncertainties in TWS-GRACE caused by its low spatial and temporal resolution. Correlation analysis between TWS-fusion and TWS-GRACE identified errors in GRACE solutions and commonly used autoregressive methods for filling data gaps. Our findings show that model developed in this study significantly improved alignment between TWS-GRACE and TWS-WB, reducing RMSE from 34.7 to 14.9 mm/month. The proposed data fusion approach based on combining GRACE observations with precipitation, evapotranspiration, and runoff data, offers a viable alternative for extending TWS-GRACE time series beyond the GRACE observational period. Additionally, our research provides valuable insights for downscaling GRACE data and addressing challenges in spatial and temporal interpolation, which remain critical in water resource studies.
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Gainers and losers of surface and terrestrial water resources in China during 1989–2016
Abstract Data and knowledge of the spatial-temporal dynamics of surface water area (SWA) and terrestrial water storage (TWS) in China are critical for sustainable management of water resources but remain very limited. Here we report annual maps of surface water bodies in China during 1989–2016 at 30m spatial resolution. We find that SWA decreases in water-poor northern China but increases in water-rich southern China during 1989–2016. Our results also reveal the spatial-temporal divergence and consistency between TWS and SWA during 2002–2016. In North China, extensive and continued losses of TWS, together with small to moderate changes of SWA, indicate long-term water stress in the region. Approximately 569 million people live in those areas with deceasing SWA or TWS trends in 2015. Our data set and the findings from this study could be used to support the government and the public to address increasing challenges of water resources and security in China.
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- Award ID(s):
- 1911955
- PAR ID:
- 10170213
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Nature Communications
- Volume:
- 11
- Issue:
- 1
- ISSN:
- 2041-1723
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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