Xia et al. (2026) A first characterization of lake ice thickness on the Tibetan Plateau by leveraging satellite altimetry and ERA5 reanalysis

Identification

• Journal: International Journal of Applied Earth Observation and Geoinformation
• Year: 2026
• Date: 2026-04-07
• Authors: Tian Xia, Laihui Luo, Wenbin Zhu, Jian Ju, Liguang Jiang
• DOI: 10.1016/j.jag.2026.105284

Research Groups

• School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen, China
• Shenzhen Raw Water CO., LTD, Shenzhen, China
• Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
• State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources (TPESER), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China

Short Summary

This study provides the first large-scale, satellite altimetry-based quantification of lake ice thickness (LIT) across 170 Tibetan Plateau lakes from 2016-2024, revealing mean annual maximum LIT values between 0.28 and 0.78 meters and an overall thinning rate of -0.8 mm per year over the past three decades, primarily driven by temperature.

Objective

• To provide the first comprehensive, large-scale quantification of lake ice thickness (LIT) across the Tibetan Plateau (TP) using satellite radar altimetry, characterizing its spatial distribution and temporal trends.

Study Configuration

• Spatial Scale: 170 lakes on the Tibetan Plateau, with individual lake areas ranging from 7 km² to 4484 km².
• Temporal Scale: Altimetry data from 2016 to 2024; reconstructed long-term lake ice thickness time series from 1990 to 2024.

Methodology and Data

• Models used: Numerical waveform fitting algorithm, FLake model, Multiple Linear Regression (MLR).
• Data sources: Multi-mission radar altimetry (Jason-3, Sentinel-3A/B, Sentinel-6A, SWOT nadir altimeter); ERA5-Land reanalysis; in-situ lake ice thickness measurements (Eling Lake, Qinghai Lake, Nam Co Lake); Sentinel-1 SAR imagery; Sentinel-2 optical imagery; Tibetan Plateau Lakes Dataset (>1 km²); lake ice phenology and bathymetric datasets.

Main Results

• The first satellite altimetry-based mapping of lake ice thickness (LIT) was achieved for 170 lakes on the Tibetan Plateau (TP) from 2016 to 2024.
• Multi-mission altimetry LIT retrievals showed high consistency, with a median difference of 18%.
• Altimetry-corrected ERA5 reanalysis significantly reduced overestimation, achieving RMSEs of 0.08 meters for Qinghai Lake and 0.14 meters for Eling Lake compared to in-situ data.
• Mean annual maximum LIT for 95% of the studied lakes ranged from 0.28 meters to 0.78 meters.
• LIT exhibited a negative correlation with lake area (decreasing by approximately 0.19 meters for every tenfold increase in area) and a positive correlation with elevation (increasing by 0.11 meters per 1000 meters elevation gain).
• An overall thinning trend of -0.8 mm per year was observed for annual maximum LIT across the TP from 1990 to 2024, with the Brahmaputra River Basin showing the fastest thinning rate (-1.71 mm per year).
• Air temperature was identified as the dominant driver of LIT variability (explaining 57.6% of variance), followed by longwave (24.1%) and shortwave radiation (17.6%).
• Lake depth and salinity were also found to be key intrinsic lake properties influencing LIT.

Contributions

• Provides the first consistent, large-scale, observation-based quantification of lake ice thickness (LIT) across the Tibetan Plateau (TP) using multi-mission satellite altimetry.
• Develops a novel approach to reconstruct long-term (1990-2024) LIT time series by correcting ERA5-Land reanalysis with altimetry-derived LIT, improving accuracy in a data-sparse region.
• Offers critical insights into the spatial distribution, temporal trends (thinning rate), and dominant climatic and intrinsic drivers of LIT variability on the TP.
• Establishes a valuable, spatially continuous, and temporally consistent dataset for future assessments of TP lake responses to climate change.

Funding

• National Natural Science Foundation of China (No. 42471348)
• National Key R&D Program of China (No. 2024YFF0808803)
• High-level University Special Fund (G03050K001)
• Shenzhen Science and Technology Program (KCXFZ20240903093659003)

Citation

@article{Xia2026first,
  author = {Xia, Tian and Luo, Laihui and Zhu, Wenbin and Ju, Jian and Jiang, Liguang},
  title = {A first characterization of lake ice thickness on the Tibetan Plateau by leveraging satellite altimetry and ERA5 reanalysis},
  journal = {International Journal of Applied Earth Observation and Geoinformation},
  year = {2026},
  doi = {10.1016/j.jag.2026.105284},
  url = {https://doi.org/10.1016/j.jag.2026.105284}
}