Paul et al. (2026) Normalized Regime Persistence: A Simple Metric to Diagnose Land Feedback States

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

Identification

• Journal: Geophysical Research Letters
• Year: 2026
• Date: 2026-08-25
• Authors: Sandipan Paul, L. Karthikeyan
• DOI: 10.1029/2026gl125188

Research Groups

• Department of Earth Sciences, University of California, Berkeley
• National Aeronautics and Space Administration (NASA) Jet Propulsion Laboratory
• European Centre for Medium-Range Weather Forecasts (ECMWF)

Short Summary

This study introduces a new observation-driven metric to characterize land feedback states using satellite-derived soil moisture variability. The research reveals that climatic gradients shape the seasonal evolution of three land feedback regimes, with distinct coupling strengths across different climate types.

Objective

• Investigate global characterization of land feedbacks and their impact on energy flux partitioning and hydroclimatic extremes

Study Configuration

• Spatial Scale: Global scale, with a focus on regional variations in land feedback regimes
• Temporal Scale: Seasonal to interannual timescales, examining the evolution of land feedback states throughout the year

Methodology and Data

• Models used: None mentioned; analysis relies on satellite-derived soil moisture variability and energy flux-based coupling diagnostics
• Data sources: Satellite data (e.g., SMOS, SMAP) for soil moisture estimates, reanalysis datasets (e.g., ERA5) for climate variables

Main Results

• Three distinct land feedback regimes are identified: weak coupling in arid regions, decoupling in humid climates during wet seasons, and dynamically interacting states in semi-arid to sub-humid regions
• Dynamically coupled states exhibit stronger and more coherent water-energy coupling, particularly across transitional climates

Contributions

• Introduces a new observation-driven metric for characterizing land feedback states, circumventing multi-variate flux dependencies
• Provides robust evidence for the existence of dynamically interacting states with distinct coupling strengths across different climate types

Funding

• NASA's Terrestrial Hydrology Program (NNX16AC44G)
• European Union's Horizon 2020 research and innovation program (grant agreement No. 776186)

Citation

@article{Paul2026Normalized,
  author = {Paul, Sandipan and Karthikeyan, L.},
  title = {Normalized Regime Persistence: A Simple Metric to Diagnose Land Feedback States},
  journal = {Geophysical Research Letters},
  year = {2026},
  doi = {10.1029/2026gl125188},
  url = {https://doi.org/10.1029/2026gl125188}
}