Fróis et al. (2026) A satellite-based assessment of ERA5 soil moisture and land surface temperature interannual co-variability

⚠️ Warning: This summary was generated from the abstract only, as the full text was not available.

Identification

• Journal: Environmental Research Letters
• Year: 2026
• Date: 2026-01-13
• Authors: Luís Fróis, Isabel F. Trigo, Wouter Dorigo, Patricia de Rosnay, Emanuel Dutra
• DOI: 10.1088/1748-9326/ae3789

Research Groups

Not explicitly mentioned in the abstract.

Short Summary

This study identifies regions with strong interannual co-variability between the diurnal amplitude of land surface temperature and surface soil moisture using Earth observations, and evaluates ERA5's performance, revealing that ERA5 underestimates this co-variability in areas with high interannual vegetation variability.

Objective

• To identify regions exhibiting a strong interannual co-variability between the diurnal amplitude of land surface temperature and surface soil moisture using Earth observations, and subsequently apply a new metric to evaluate the fifth reanalysis from the European Centre for Medium-Range Weather Forecasting (ERA5).

Study Configuration

• Spatial Scale: 0° Meteosat Second Generation region, encompassing Africa and Europe.
• Temporal Scale: 2004–2023 (20 years).

Methodology and Data

• Models used: ERA5 (for evaluation). A new metric was introduced to quantify soil moisture-temperature interannual co-variability.
• Data sources:
  • Land surface temperature: European Organization for the Exploitation of Meteorological Satellites Applications Facility on Land Surface Analysis (LSA-SAF).
  • Soil moisture: Copernicus Climate Change Service (C3S).

Main Results

• Earth observations and ERA5 demonstrate similar spatial co-variability patterns across a significant portion of the domain, particularly highlighting regions of transition between climate zones.
• ERA5 shows weaker co-variability in regions characterized by large interannual vegetation variability compared to Earth observations.

Contributions

• Introduction of a novel metric to quantify the interannual co-variability between soil moisture and land surface temperature using satellite data.
• Comprehensive evaluation of ERA5's capacity to capture this co-variability, identifying specific limitations in regions with substantial interannual vegetation variability.
• Suggestion that a dynamic representation of vegetation status, beyond mean annual cycles, is crucial for accurately modeling land surface temperature and its co-variability with soil moisture in reanalysis products like ERA5.

Funding

Not explicitly mentioned in the abstract.

Citation

@article{Fróis2026satellitebased,
  author = {Fróis, Luís and Trigo, Isabel F. and Dorigo, Wouter and Rosnay, Patricia de and Dutra, Emanuel},
  title = {A satellite-based assessment of ERA5 soil moisture and land surface temperature interannual co-variability},
  journal = {Environmental Research Letters},
  year = {2026},
  doi = {10.1088/1748-9326/ae3789},
  url = {https://doi.org/10.1088/1748-9326/ae3789}
}