Ercan et al. (2025) Trend analysis of drought in Antalya basin, Türkiye, using classical and innovative approaches

Identification

• Journal: Acta Geophysica
• Year: 2025
• Date: 2025-12-08
• Authors: Cansu Ercan, Ahmad Abu Arra, Eyüp Şişman
• DOI: 10.1007/s11600-025-01722-2

Research Groups

• Department of Civil Engineering, Yildiz Technical University, Istanbul, Türkiye
• Department of Civil and Architectural Engineering, An-Najah National University, Nablus, Palestine

Short Summary

This study spatiotemporally analyzed drought trends in the Antalya basin, Türkiye, from 1969 to 2022 using classical (Mann–Kendall, Sen’s slope) and innovative (Frequency Innovative Trend Analysis) methods with the Standardized Precipitation Index. It revealed an increasing trend in drought events, particularly for longer timescales and in the southern coastal parts of the region.

Objective

• To spatiotemporally analyze drought trends in the Antalya basin, Türkiye, using the Standardized Precipitation Index (SPI) at multiple timescales, employing classical (Mann–Kendall, Sen’s slope) and innovative (Frequency Innovative Trend Analysis) methodologies, and to assess their implications for water resource management and agriculture.

Study Configuration

• Spatial Scale: Antalya basin, Türkiye, located in the southern part of Türkiye, extending between 36°–38° N and 30°–32° E. The study included 14 meteorological stations (9 within the basin, 5 adjacent).
• Temporal Scale: Monthly precipitation data from 1969 to 2022 (54 years).

Methodology and Data

• Models used: Standardized Precipitation Index (SPI), Mann–Kendall (MK) test, Sen’s slope (SS), Frequency Innovative Trend Analysis (F-ITA), Climatol v4.1.0 (R package for data quality control, gap-filling, homogeneity, and clustering), Inverse Distance Weighting (IDW) interpolation.
• Data sources: Monthly precipitation data from 14 meteorological stations provided by the Turkish State Meteorological Service (TSMS).

Main Results

• An increasing trend in drought events was generally observed for SPI-3 and SPI-6 based on classical methods and F-ITA graphs for specific stations.
• For the long timescale (SPI-12), a significant drought trend was evident across all stations, accompanied by increased drought frequencies. For example, Alanya station showed a monotonic increasing trend, with frequencies of Moderate Drought (MD), Severe Drought (SD), Extreme Drought (ED), and Exceptional Drought (EXD) approximately doubling over the study period.
• The spatial distribution of slopes computed by Sen’s slope (SS) and Innovative Trend Analysis (ITA) methods, along with their respective actual trends, exhibited significant parallels. Both methods identified the maximum slope in the same region for all timescales.
• More frequent drought events and an increased drought trend were found in the southern parts of the region near the coast, with the southern and southeastern parts of the study area exhibiting the highest trends and slopes.
• For SPI-12, negative trends were most pronounced in southern regions (e.g., Alanya and Manavgat), with SS values up to -0.002 standard deviations per month and an actual trend of -1.3 standard deviations, indicating the maximum slope compared to other timescales.

Contributions

• First application of the Frequency Innovative Trend Analysis (F-ITA) method, including novel drought classification, histograms, and frequencies, for drought trend analysis in the Antalya basin.
• Spatial calculation and comparison of actual trends using both classical (Mann–Kendall, Sen’s slope) and innovative (F-ITA) methods on a regional scale.
• Provides crucial insights for sustainable water resource management and agricultural planning in the Antalya basin, addressing a significant gap in existing literature for this region.

Funding

• Scientific Research Projects (BAP) Coordination Unit of Yildiz Technical University (Project ID: 6558, Project code: FYL-2024-6558).

Citation

@article{Ercan2025Trend,
  author = {Ercan, Cansu and Arra, Ahmad Abu and Şişman, Eyüp},
  title = {Trend analysis of drought in Antalya basin, Türkiye, using classical and innovative approaches},
  journal = {Acta Geophysica},
  year = {2025},
  doi = {10.1007/s11600-025-01722-2},
  url = {https://doi.org/10.1007/s11600-025-01722-2}
}