Elvanidi et al. (2025) Assessment of Future Water Stress of Winter Wheat and Olive Trees in Greece Using High-Resolution Climate Model Projections

Identification

• Journal: Agronomy
• Year: 2025
• Date: 2025-12-22
• Authors: A. Elvanidi, P. Maletsika, Nikolaos Nikolaos Katsoulas, Giorgos Papadopoulos, Dimitrios Melas, Kostas Douvis, Ioannis Faraslis, Stavros Keppas, Ioannis Stergiou, Anastasia Poupkou, Dimitrios Voloudakis, John Kapsomenakis, Dimitris K. Papanastasiou
• DOI: 10.3390/agronomy16010035

Research Groups

• Department of Agriculture Crop Production and Rural Environment, University of Thessaly, Volos, Greece
• Laboratory of Atmospheric Physics, School of Physics, Aristotle University of Thessaloniki, Thessaloniki, Greece
• Atmospheric Monitoring and Modeling Services, Center for Interdisciplinary Research and Innovation, Aristotle University of Thessaloniki, Thessaloniki, Greece
• Research Centre for Atmospheric Physics and Climatology, Academy of Athens, Athens, Greece
• Department of Environmental Sciences, University of Thessaly, Larissa, Greece

Short Summary

This study evaluates the future water stress of winter wheat and olive trees in Greece by integrating the Crop Water Stress Index (CWSI) with high-resolution regional climate simulations, projecting increased water stress for both crops by mid-century under the SSP2-4.5 scenario.

Objective

• To quantify how future mid-century (2046–2055) climate conditions may alter the timing, magnitude, and spatial distribution of water stress for winter wheat and olive trees across Greece.

Study Configuration

• Spatial Scale: Greece, with simulations at 10 km horizontal resolution. Analysis focused on key winter wheat-, olive oil-, and table olive-producing Greek regions (EU NUTS 2).
• Temporal Scale: Two decadal periods: current climate (2005–2014) as reference, and near-future climate (2046–2055) under the SSP2-4.5 emission scenario.

Methodology and Data

• Models used:
  • Weather Research and Forecasting (WRF) model (version 4.5) for regional climate simulations.
  • Crop Water Stress Index (CWSI) for assessing water stress.
• Data sources:
  • Bias-corrected global dataset based on 18 models from the Coupled Model Intercomparison Project 6 (CMIP6) and ERA5 reanalysis for WRF boundary conditions.
  • ERA5-Land dataset (approximately 9 km resolution) for WRF model performance evaluation.
  • FAO definitions for winter wheat growing stages.
  • Hellenic Statistical Authority (ELSTAT) for regional crop production data.

Main Results

• Future climate projections (2046–2055) under the SSP2-4.5 scenario indicate a mean air temperature increase of 1.1–1.7 °C across Greece, with more pronounced warming in central and northern Greece (up to 1.7 °C).
• Mean relative humidity is projected to decrease across most of Greece, reaching up to -3.5% in the Pindos mountain range.
• Mean CWSI is projected to increase by up to 6% for winter wheat and up to 4% for olive trees in most of the country.
• For winter wheat, water stress (CWSI > 0.5) is projected to occur during all three FAO-defined growing stages, with more pronounced stress in Central Greece, Thessaly, and Western Macedonia (CWSI increases > 3% in over 70% of the area during specific growing stages).
• For olive trees, localized water stress hotspots are detected, with CWSI increases of 4–7% projected in Western Macedonia and mountainous areas of Central Greece, and 1–2.5% increases across 61.9% of the country.

Contributions

• First study to use decadal regional climate simulations at a high spatial resolution (10 km) for the Mediterranean region, driven by the CMIP6 framework under SSP scenarios, for assessing crop water stress.
• Integrated the WRF model with the Crop Water Stress Index (CWSI) and explicit crop phenology to enable stage-specific potential water stress mapping for winter wheat and olive trees within a single, comparable framework.
• Provided spatially explicit stress diagnostics without variety-specific calibration, offering decision-support metrics for irrigation scheduling and adaptation planning in Greece.
• Established a transferable modeling framework applicable to other crops and regions in the Mediterranean.

Funding

• Project: "Crop and Livestock Stress under Climate Change Scenarios (AGRO FUTURE CLIMATE STRESS)"
• Funding Program: National Recovery and Resilience Plan Greece 2.0
• Funding Source: European Union—NextGenerationEU (implementation body: HFRI)

Citation

@article{Elvanidi2025Assessment,
  author = {Elvanidi, A. and Maletsika, P. and Katsoulas, Nikolaos Nikolaos and Papadopoulos, Giorgos and Melas, Dimitrios and Douvis, Kostas and Faraslis, Ioannis and Keppas, Stavros and Stergiou, Ioannis and Poupkou, Anastasia and Voloudakis, Dimitrios and Kapsomenakis, John and Papanastasiou, Dimitris K.},
  title = {Assessment of Future Water Stress of Winter Wheat and Olive Trees in Greece Using High-Resolution Climate Model Projections},
  journal = {Agronomy},
  year = {2025},
  doi = {10.3390/agronomy16010035},
  url = {https://doi.org/10.3390/agronomy16010035}
}