Climate change and frequency–intensity–duration (FID) curves for Florya station, Istanbul

Abstract

In recent decades, according to Intergovernmental Panel on Climate Change reports, the impact of climate change on hydro‐meteorological events has increased substantially. This point is obvious in many rainfall–runoff time series as a negative or positive trend. In this paper, first of all such trend possibilities are searched graphically according to Şen's 1:1 (45°) straight‐line method, which has been proposed instead of the classical methods including Mann–Kendall, Spearman's rho and linear regression approaches. Additionally, these trends are quantified by using frequency–intensity–duration (FID) curves, instead of intensity–duration–frequency (IDF) curves obtained from a set of single storm rainfall records. The FID curves provide practical, easy and clear representation of rainfall intensity variation through fitted exponential curves with coefficient of determination that is almost equal to 1 (R2 ≈ 1). FID curves are drawn on semilogarithmic paper with rainfall intensity estimations from the convenient Gamma probability distribution functions (PDFs) or cumulative distribution functions (CDFs). In this study 46‐year rainfall records are used from Florya station, which is located in Istanbul, Turkey. The comparisons generally indicated that a negative trend is valid at this station, and accordingly, representative FID curves are obtained on ordinary and semilogarithmic papers for this station.

Investigation of The Effect of Climate Change on Extreme Precipitation: Tekirdağ Case

“…Second half of the time series is latter half and places on the vertical (Y) axis. The existence of a trend is visually inspected by the position of scattered points relative to 1:1 line (Şen, 2012;Haktanir & Citakoglu, 2014;Güçlü et al, 2018;Ali et al, 2019;Alifujiang et. al., 2020).…”

“…Sarhadi et al (2017) and Cheng and Aghakouchak (2014) also urge the need of updated extreme rainfall used in the infrastructure design process. In the IDF/DDF curve generations updating is important as new records become available because some natural effects may cause alterations in the frequency or the magnitude of rainfall events (Güçlü et al, 2018). Hence future changes became into consideration to obtain appropriate and futureproofing design.…”

Kuzey Marmara Otoyolunda dere köprüsü tasarımı ve uygulaması: Alemdağ dere köprüsü örneği

“…Bu analiz için yukarıda da ismi verilen bazı yöntemler ortaya atılmıştır. Birçok araştırmacı [19][20][21][22][23][24] [18].…”

“…Bu aşamadan sonra seçilen sıklık esas alınarak şiddet değerleri belirlenir. Mesela, n yıllık frekans (sıklık) için F=1/n denklemi kullanılarak ODF'nun sağ kuyruğu veya YDF üzerinde 1-1/n'ye karşılık gelen sonuç göz önünde tutularak yağış şiddeti değerleri elde edilir (Şekil 2) [24].…”

İstanbul İçin Standart Süreli Gözlenen En Büyük Yağışların Eğilimleri

“…Korkmaz ve arkadaşları [23] Orta Karadeniz Bölgesinde 8 Meteoroloji Gözlem istasyonunda YŞST eğrilerindeki dönemsel değişimleri incelemişler, iki dönem ve tüm periyot için 2 istasyonda belirgin artış trendi tespit etmişlerdir. Güçlü ve arkadaşları [24] Florya istasyonunda yağış şiddetlerinde ise azalma eğilimi tespit etmişlerdir.…”