Drought assessment in the Mediterranean Region of Türkiye

Fuzzy c-means (FCM) and innovative trend analysis (YTA, Innovative Trend Analysis) were used to investigate the meteorological drought across the Mediterranean Region of Türkiye. To this aim, the study area was clustered and the standardized precipitation index (SPI) at 3, 6, and 12 month (SPI-3, SPI-6, and SPI-12) accumulation periods were calculated using long-term observed precipitation data between 1970 and 2021 from 35 meteorological stations spread over the study area. The severity and duration of the extreme drought (AK), severe drought (SK), and moderate drought (OK) occurrences were tracked at each cluster and each station. The spatiotemporal changes in SPI indicated that OK events predominated in all seasons, however the study area has had a large number of SK and AK occurrences over the study period. SPI-3 data of Senirkent station; SPI-6 and SPI-12 data of Dörtyol station show that these stations have seen the highest number of drought occurrences. Moreover, reconnaissance drought index (RDIst,) at 3, 6, and 12 month accumulation periods were calculated for each station. The Mediterranean Region of Türkiye can be studied in three clusters: the high elevations in the north that receive the least amount of yearly precipitation, the eastern region at relatively low altitudes, and the western coastline region, according to the fuzzy cluster analysis. The western coastal cluster was exposed to prolonged OK, SK, and AK events compared to other clusters. Since 1995, there have been more OK, SK, and AK events, according to the YTA at all clusters. Considering SPI and RDIst results, compatible results are obtained.