Drought Trends in Türkiye Under Global Warming Conditions

Fatih Sekendur; Ali Ünlükara

doi:10.15832/ankutbd.1779288

Drought Trends in Türkiye Under Global Warming Conditions

Abstract

The methods used in monitoring the increasing drought are vitally significant. In order to determine and monitor drought, many scientific studies have been carried out in our country, especially using the standardized precipitation index (SPI). However, due to increasing temperatures and evaporation, there is a need for studies showing the spatio-temporal change of drought at the country scale according to the standardized precipitation evapotranspiration index (SPEI), which also takes evaporation into account. The change in drought indices according to different evapotranspiration methods is also of interest. In this study, spatio-temporal comparison of drought trend and trend magnitude at 1, 6 and 12-month time scales according to SPI and SPEI indices was aimed by using meteorological observation data of 81 meteorological stations in Türkiye between 1980-2019. FAO-56 Penman-Monteith (PM) and Hargreaves (HG) reference evapotranspiration methods were used to calculate the SPEI index. Temporal trend analyses were conducted by Modified Mann-Kendall method and drought slope magnitude analyses by Sen’s Slope Estimator and spatial analyses by IDW method. According to the SPI index trend analysis for a 1, 6 and 12- month time scale, especially the drought in the Black Sea, the Marmara and Aegean Regions of Türkiye showed a significant downward trend while a significant upward trend of drought was seen in the other regions. The findings revealed that the humid periods were more prevailing than the dry periods in these areas that have downward drought trend. Unlike the SPI, the trend analysis of SPEIPM and SPEIHG index, downward trend of drought was only encountered in the coastal provinces of the Aegean region, the Central Black Sea, and the West Marmara Region. A significant upward trend of drought was observed in the majority of Central Anatolia, Eastern Anatolia, and Southeastern Anatolia Regions according to the SPEIPM and SPEIHG index.

Keywords

Thanks

The authors are thankful for Turkish State Meteorological Service for providing all necessary meteorological parameters.

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Details

Primary Language

English

Subjects

Biosystem, Agricultural Hydrology, Agricultural Spatial Analysis and Modelling

Journal Section

Research Article

Authors

Fatih Sekendur ^*
0000-0001-6509-2952
Türkiye

Ali Ünlükara
0000-0003-4931-8100
Türkiye

Publication Date

October 12, 2026

Submission Date

September 6, 2025

Acceptance Date

May 12, 2026

Published in Issue

Year 2026 Volume: 32 Number: 4

DOI

https://doi.org/10.15832/ankutbd.1779288

IZ

https://izlik.org/JA94UN49JA

Cite

RIS / Bibtex

APA

Sekendur, F., & Ünlükara, A. (2026). Drought Trends in Türkiye Under Global Warming Conditions. Journal of Agricultural Sciences, 32(4), 1008-1029. https://doi.org/10.15832/ankutbd.1779288

AMA

1.Sekendur F, Ünlükara A. Drought Trends in Türkiye Under Global Warming Conditions. J Agr Sci-Tarim Bili. 2026;32(4):1008-1029. doi:10.15832/ankutbd.1779288

Chicago

Sekendur, Fatih, and Ali Ünlükara. 2026. “Drought Trends in Türkiye Under Global Warming Conditions”. Journal of Agricultural Sciences 32 (4): 1008-29. https://doi.org/10.15832/ankutbd.1779288.

EndNote

Sekendur F, Ünlükara A (October 1, 2026) Drought Trends in Türkiye Under Global Warming Conditions. Journal of Agricultural Sciences 32 4 1008–1029.

IEEE

[1]F. Sekendur and A. Ünlükara, “Drought Trends in Türkiye Under Global Warming Conditions”, J Agr Sci-Tarim Bili, vol. 32, no. 4, pp. 1008–1029, Oct. 2026, doi: 10.15832/ankutbd.1779288.

ISNAD

Sekendur, Fatih - Ünlükara, Ali. “Drought Trends in Türkiye Under Global Warming Conditions”. Journal of Agricultural Sciences 32/4 (October 1, 2026): 1008-1029. https://doi.org/10.15832/ankutbd.1779288.

JAMA

1.Sekendur F, Ünlükara A. Drought Trends in Türkiye Under Global Warming Conditions. J Agr Sci-Tarim Bili. 2026;32:1008–1029.

MLA

Sekendur, Fatih, and Ali Ünlükara. “Drought Trends in Türkiye Under Global Warming Conditions”. Journal of Agricultural Sciences, vol. 32, no. 4, Oct. 2026, pp. 1008-29, doi:10.15832/ankutbd.1779288.

Vancouver

1.Fatih Sekendur, Ali Ünlükara. Drought Trends in Türkiye Under Global Warming Conditions. J Agr Sci-Tarim Bili. 2026 Oct. 1;32(4):1008-29. doi:10.15832/ankutbd.1779288