Decadal variability analysis of extreme precipitation in Turkey and its relationship with teleconnection patterns


Tezin Türü: Yüksek Lisans

Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Mühendislik Fakültesi, İnşaat Mühendisliği Bölümü, Türkiye

Tezin Onay Tarihi: 2017

Öğrenci: EREN DÜZENLİ

Danışman: MUSTAFA TUĞRUL YILMAZ

Özet:

Natural disasters as droughts and floods originate as a consequence of excessive decrease or increase in precipitation amount and/or frequency, while the variability in the climate significantly impacts the expected change in precipitation. Given that many global ocean-atmosphere teleconnection patterns (AO, WeMO, NAO, SOI, etc.) are tightly related with the climate variability and show decadal/multi-decadal oscillations, it is important to analyze precipitation variability at the decadal time-scale to understand the (expected) variability in the climate more effectively. In this study, decadal oscillations of extreme precipitation in Turkey are investigated using Quantile Perturbation Method (QPM). Daily precipitation data observed over 67 stations in Turkey between 1955 and 2014 are utilized in the analyses. AO, WeMO, NAO, and SOI teleconnection patterns are examined for their relation with the extreme precipitation variability to understand the potential drivers of extreme precipitation in Turkey. According to the analysis based on single drivers, NAO is identified as the most effective driver of Turkey’s extreme precipitation among 4 climate indices, while AO has a similar effect. When the teleconnection patterns are investigated in pairs, combination of NAO and SOI results in the highest response to the winter extremes in Turkey.