Drought analysis using CORDEX simulations over the mediterranean climate regions of Turkey

Poyraz, Anıl Yıldırım
Drought has been a significant result of climate change that causes variance on precipitation regimes. Mediterranean region is one of the hotspots of the world in this respect. Dry summers and rainy winters -the characteristic of this climate type- makes this region more vulnerable to the effects of climate change. Hence, it is important to monitor drought considering the increasing population and economic facilities in the regions that are under Mediterranean climate conditions in Turkey. This study aims to assess the trends in drought by applying the Standardized Precipitation Index(SPI) for 5 timescales – from 1 month to 12 months. The model grid data that corresponds to meteorological stations distributed from south to west within the study area was obtained from 12 different Global Circulation Model / Regional Climate Model couplings of CORDEX project. Observed and modeled prediction data were compared for reference period (1971-2005) in order to detect the most reliable models. Afterwards, modified Mann-Kendall trend test was applied on the SPI and annual precipitation values for the entire period (1972-2100). The trends were estimated by linear regression for the locations in which Mann-Kendall results indicated a significant change. In conclusion, a persistent increasing drought trend was detected for Muğla and western Antalya parts such that all models are coherent. On the other hand, the divergence of the trends for some regions according to different models signifies the discrepancy of models. Besides, the drought trends are decreasing for some regions (especially Southern Marmara) as the timescale increases.


Poyraz, Anıl; Yücel, İsmail (2018-06-02)
This study aims to assess the trends in drought by using the Standardized Precipitation Index(SPI) for 14 stations from Mediterranean climate region of Turkey. The SPI values for different timescales - from 1month to 1 year - are estimated for past and future by using the observed, uncorrected and bias corrected model data. The model data that correspond the grids which consist these 14 stations was obtained from 12 different climate models on CORDEX project. Bias correction method was applied using equival...
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Citation Formats
A. Y. Poyraz, “Drought analysis using CORDEX simulations over the mediterranean climate regions of Turkey,” M.S. - Master of Science, Middle East Technical University, 2018.