Fang (2025) Global Standardized Precipitation Evapotranspiration Index (SPEI) for the Common Era, calculated using monthly climate variables from MPI-ESM model simulations from past2k experiment in CMIP6

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

Identification

• Journal: Open MIND
• Year: 2025
• Date: 2025-10-15
• Authors: Miao Fang
• DOI: 10.5281/zenodo.18411291

Research Groups

• Max Planck Institute for Meteorology (MPI-M) (source of the MPI-ESM1-2-LR model outputs used as input data)
• Food and Agriculture Organization of the United Nations (FAO) (source of recommended Penman-Monteith formula for PET calculation)
• Vicente-Serrano et al. (developers of the Standardized Precipitation Evapotranspiration Index (SPEI) calculation formula)

Short Summary

This study describes the generation of a global gridded Standardized Precipitation Evapotranspiration Index (SPEI) dataset for the past 2000 years (1 CE to 2014 CE) at monthly, seasonal, and annual time scales, utilizing climate model outputs and established drought index methodologies.

Objective

• To generate a global gridded Standardized Precipitation Evapotapotranspiration Index (SPEI) dataset for the past 2000 years (1 CE to 2014 CE) at multiple time scales (monthly, seasonal, annual) to facilitate studies on spatiotemporal drought variations.

Study Configuration

• Spatial Scale: Global, gridded, with a resolution of approximately 250 km (corresponding to a 1.875 degree latitude-longitude grid).
• Temporal Scale: January 1 CE to December 2014 CE (2014 years), with SPEI calculated at monthly (SPEI-01), seasonal (SPEI-03), and annual (SPEI-12) scales.

Methodology and Data

• Models used:
  • MPI-ESM1-2-LR (CMIP6 past2k experiment) for primary climate variable outputs.
  • Penman-Monteith formula (FAO recommended) for potential evapotranspiration (PET) calculation.
  • Standardized Precipitation Evapotranspiration Index (SPEI) calculation formula (Vicente-Serrano et al., 2010).
• Data sources:
  • Monthly climate variables (tasmin, tasmax, pr, ps, sfcWind, rsds, rsdt, hurs) from the MPI-ESM1-2-LR model outputs, downloaded from the Earth System Grid Federation (ESGF).
  • Wind speed at 10 meters converted to 2 meters for PET calculation as per FAO guidelines.

Main Results

• A global gridded SPEI dataset covering the period from 1 CE to 2014 CE was successfully generated.
• The dataset provides SPEI values at three distinct time scales: monthly (SPEI-01), seasonal (SPEI-03), and annual (SPEI-12).
• The spatial resolution of the generated SPEI data is approximately 250 km (1.875 degrees latitude-longitude).
• The data is formatted in NetCDF4, including comprehensive metadata, making it suitable for sharing and analysis of global and regional drought spatiotemporal variations.

Contributions

• Generation of a novel, long-term global gridded SPEI dataset spanning the past 2000 years, offering an unprecedented temporal depth for drought research.
• Provision of multi-scalar SPEI data (monthly, seasonal, annual), enabling detailed analysis of drought impacts across various sectors (e.g., short-term meteorological, agricultural, hydrological).
• The dataset's adherence to standard meteorological data formats (NetCDF4) and inclusion of metadata promotes data accessibility and reusability for the scientific community.

Funding

No funding information was provided in the text.

Citation

@article{Fang2025Global,
  author = {Fang, Miao},
  title = {Global Standardized Precipitation Evapotranspiration Index (SPEI) for the Common Era, calculated using monthly climate variables from MPI-ESM model simulations from past2k experiment in CMIP6},
  journal = {Open MIND},
  year = {2025},
  doi = {10.5281/zenodo.18411291},
  url = {https://doi.org/10.5281/zenodo.18411291}
}