HATİCE ÇITAKOĞLU, VAHDETTİN DEMİR, TEFARUK HAKTANIR

L−MOMENTLER YÖNTEMİYLE KARADENİZ’E DÖKÜLEN AKARSULARA AİT YILLIK ANLIK MAKSİMUM AKIM DEĞERLERİNİN BÖLGESEL FREKANS ANALİZİ

Bu araştırmada, Karadeniz’e dökülen akarsulardaki 52 adet akım gözlem istasyonuna ait Yıllık Anlık Maksimum Akım (YAMA) verileri kullanılarak L-Momentler yöntemiyle bölgesel frekans analizi yapılmıştır. Hosking tarafından sağlanan bilgisayar programı kullanılarak gerçekleştirilen uygulama beş büyük havzayı kapsayan çalışma alanının tek başına bir bütün olarak homojen bir bölge olmadığını ortaya çıkarmıştır (H1=13,60>>1,0). Bu havzaların fizyografik ve hidrolojik özellikleri göz önüne alınarak ve H1 kriterine göre, çalışma alanı 11 farklı homojen bölgeye ayrılmıştır. ZDIST uygunluk testi sonuçlarına göre 11 alt bölgenin beşinde Genelleştirilmiş Normal dağılım en uygun olasılık dağılımı olarak belirlenmiştir ve Genelleştirilmiş Ekstrem Değerler, Pearson Tip 3 ve Genelleştirilmiş Lojistik dağılımları sırasıyla üç, iki ve bir alt bölgede en uygun dağılım olarak bulunmuştur. Bu dağılımlarla yapılan indeks‒taşkın frekans analizleri sonucunda, çalışma alanı için 2 yıl ile 1000 yıl arası tekerrür periyotlarında grid yöntem ile bölgesel Yıllık Anlık Maksimum Akım haritaları oluşturulmuştur.

Anahtar Kelimeler:

L−Momentler, taşkın, grid yöntem, radyal tabanlı fonksiyon

REGIONAL FREQUENCY ANALYSIS OF ANNUAL FLOOD PEAKS OF NATURAL STREAMS DISCHARGING TO THE BLACK SEA BY THE L-MOMENTS METHOD

In this study, Regional Frequency Analysis of annual flood peaks (AFP) series of natural streams discharging to the Black Sea using AFP series recorded 52 stream-gauging stations is done by L-Moments method. Application of method performed by using computer program provided by Hosking reveals that working area including five major basins cannot be treated as a single homogeneous region as a whole (H1=13.6>>1.0). Taking into consideration physiographical and hydrological peculiarities of these basins and according to H1 criteria, working area is divided into 11 different homogeneous regions. According to ZDIST goodness-of-fit criterion, Generalized Normal Distribution is determined to be the best probability distribution in five of eleven sub-regions and Generalized Extreme Values, Pearson Type 3, Generalized Logistic distributions are found to be the best in three, two, and one sub-regions, respectively. As a result of index-flood frequency analysis with these distributions, regional annual flood peaks maps covering range of return periods from 2 to 1000 years are produced by grid method for working area.

Keywords:

L−Moments, flood, grid method, radial−based function,

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