Taylor et al. (2026) Assessing the Ability of Tree-Ring Derived Aridity Records to Detect Compound Drought and Heatwave Events

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

Identification

• Journal: Journal of Climate
• Year: 2026
• Date: 2026-03-24
• Authors: K. J. Taylor, Michael N. Evans, Andrew Schurer, Gabriele C. Hegerl
• DOI: 10.1175/jcli-d-25-0472.1

Research Groups

Not explicitly mentioned in the abstract.

Short Summary

This study investigates whether extremes in the Palmer Drought Severity Index (PDSI), particularly those derived from tree-ring reconstructions, can identify past compound drought and heatwave events (CDHWs) in North America and Europe. It finds that in regions with strong land-atmosphere coupling, such as Central North America and Eastern Europe, negative summer PDSI values co-occur with precipitation deficits and high temperatures, allowing tree-ring PDSI reconstructions to identify CDHWs predating instrumental records.

Objective

• To quantify the relative roles of precipitation and temperature in determining variation in the Palmer Drought Severity Index (PDSI) across IPCC AR6 reference regions in North America and Europe, and to understand whether extremes in PDSI may be used to identify past compound drought and heatwave (CDHW) events.

Study Configuration

• Spatial Scale: IPCC AR6 reference regions in North America and Europe.
• Temporal Scale: Boreal summer season, covering both the instrumental period and periods predating instrumental records (paleoclimate).

Methodology and Data

• Models used: Palmer Drought Severity Index (PDSI).
• Data sources: Instrumental climate data, paleoclimate archives (specifically tree-ring derived reconstructions of PDSI and tree-ring width).

Main Results

• Tree-ring derived reconstructions of PDSI effectively capture extremes in instrumental PDSI during boreal summer.
• Precipitation is a significant predictor of both instrumental and tree-ring derived PDSI across all but one studied region.
• The importance of temperature in determining PDSI varies depending on the strength of land-atmosphere coupling in a given region.
• In Central North America and Eastern Europe, regions characterized by strong land-atmosphere coupling, the most negative summer season PDSI values coincide with significant precipitation deficits and high temperatures.
• In these strongly coupled regions, PDSI reconstructions can be used to identify CDHW events that occurred prior to the instrumental record.
• Reconstructions of PDSI derived from tree-ring width generally appear more sensitive to temperature compared to instrumental data.

Contributions

• Provides a novel approach to using paleoclimate archives (tree-rings) to understand the compound nature of past drought and heatwave events, extending beyond previous uses for identifying only summer drought.
• Identifies specific regions (Central North America and Eastern Europe) where tree-ring derived PDSI reconstructions are reliable indicators for past CDHW events, enhancing understanding of their drivers and historical frequency.
• Highlights the regional variability in the influence of temperature on PDSI, linking it to land-atmosphere coupling strength.

Funding

Not explicitly mentioned in the abstract.

Citation

@article{Taylor2026Assessing,
  author = {Taylor, K. J. and Evans, Michael N. and Schurer, Andrew and Hegerl, Gabriele C.},
  title = {Assessing the Ability of Tree-Ring Derived Aridity Records to Detect Compound Drought and Heatwave Events},
  journal = {Journal of Climate},
  year = {2026},
  doi = {10.1175/jcli-d-25-0472.1},
  url = {https://doi.org/10.1175/jcli-d-25-0472.1}
}