Climate change impacts on meteorological drought using SPI and SPEI: case study of Ankara, Turkey

Sorman, Ali Unal
Kahya, Ercan
Afshar, Mahdı Hesamı
Using regionally downscaled and adjusted outputs of three global climate models (GCMs), meteorological drought analysis was accomplished across Ankara, the capital city of Turkey. To this end, standardized precipitation index (SPI) and standardized precipitation evapotranspiration index (SPEI) were projected under (representative concentration pathway) RCP4.5 and RCP8.5 greenhouse gas scenarios. In general, our results show that Ankara experienced six severe and two extreme drought events during the reference period, 1971-2000. However, the projections indicate fewer drought events for the near-future period of 2016-2040, with no potential extreme drought events. While the RCP4.5 scenario showed that dry spells will be dominant in the second half of the near-future period, the RCP8.5 scenario projected that dry spells will be evenly distributed during the entire near-future period.


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Tekeli, AE; Sensoy, A; Sorman, A; Akyürek, Sevda Zuhal; Sorman, U (Wiley, 2006-03-15)
Over the ablation period of 2004, daily snow albedo values retrieved from the moderate-resolution imaging spectroradiometer (MODIS) Terra were compared with ground-based albedo measurements. Two data sets are used for this study. The first data set is from two automatic weather stations (AWS) located at fixed points in Karasu basin in eastern Turkey. This provided the temporal assessment of MODIS daily snow albedo values. The second data set, consisting of 19 observation points randomly distributed around o...
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Accuracy assessment of precipitation retrievals is a pre-requisite for many hydrological studies as it helps to understand the source and the magnitude of the uncertainty in hydrological response variables, particularly over regions with complex topography. This study evaluates GPM IMERGv05, TMPA 3B42V7, ERA-Interim, and ERA5 precipitation products using 256 ground-based gauge stations between 2014 and 2018 over Turkey known to have complex topography and varying climate. Error statistics, categorical perfo...
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Estimation of groundwater recharge to an unconfined aquifer is studied using analytical and numerical techniques and results are compared with field observations. There is an acute need for such estimation in water balance studies in arid climates, and the case study in this paper is for such a region. The wetting front movement in the unsaturated zone depends on antecedent soil moisture, the ponded water depth and its duration, and on the position of the water table and the hydraulic properties of the unsa...
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Altınbilek, Doğan H. (Informa UK Limited, 2006-06-01)
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Citation Formats
A. D. MEHR, A. U. Sorman, E. Kahya, and M. H. Afshar, “Climate change impacts on meteorological drought using SPI and SPEI: case study of Ankara, Turkey,” HYDROLOGICAL SCIENCES JOURNAL-JOURNAL DES SCIENCES HYDROLOGIQUES, pp. 0–0, 2019, Accessed: 00, 2020. [Online]. Available: