EVALUATION OF KRIGING WITH EXTERNAL DRIFT METHOD IN SPATIAL MODELLING OF PRECIPITATION: A CASE OF AEGEAN REGION, TURKEY

Yıl 2018, Sayı: 56, 1 - 18, 27.04.2018

Olgu Aydın

Öz

The structures and
geographical formations observed in the Aegean region of Turkey differ from the
other coastal regions of the country. Especially, elevation and aspect have
different characteristics in this region. Thus, the precipitation conditions
are influenced and the annual precipitation amounts observed in the plains are
not consistent. In this study, Kriging with an External Drift was applied to
obtain a prediction map of precipitation in the Aegean region. Annual mean
total precipitation data obtained from 36 stations (1976–2010) were used. Elevation
was used as a secondary variable in Kriging with an External Drift
calculations. The R² of 0.35 shows that at least one quarter of the
precipitation behaviour can be explained by the model. A distribution that
complies with the orographic extension draws attention in the Kriging with an
External Drift precipitation estimation map. The results show that Kriging with
an External Drift and incorporation of elevation as a secondary variable could
be used to supplement sparse observations in the mapping of precipitation.

Anahtar Kelimeler

precipitation, elevation, geostatistics

YAĞIŞIN MEKÂNSAL OLARAK MODELLENMESINDE KRIGING WITH EXTERNAL DRIFT YÖNTEMININ DEĞERLENDIRILMESI:EGE BÖLGESI

Öz

TEge Bölgesi’nde görülen coğrafi oluşumlar
ve yapılar, Türkiye’nin diğer kıyı bölgerinden farklılık göstermektedir.
Özellikle bu bölgedeki yükseklik ve bakı, farklı karekteristiklere sahiptir. Bu
nedenle, yağış durumu etkilenmektedir ve düzlük alanlarda görülen yıllık yağış
miktarlarında bir istikrar gözlenmemektedir. Bu çalışmada, Ege Bölgesi’nde
yağış haritası tahmini için Kriging with External Drift yöntemi kullanılmıştır.
Çalışmada 36 istasyonda 1976–2010
yıllarında ölçülmüş aylık ortalama yağış değerlerinden elde edilen yıllık
toplam yağış verisi kullanılmıştır. Yağış tahmininde yardımcı değişken olarak
yükseklik verisinden yararlanılmıştır. Kriging with External Drift yağış tahmin
haritasında orografik uzanımlar ile uyumlu bir dağılım dikkat çekmektedir.
Sonuçlar, yüksekliğin yardımcı değişken olarak kullanıldığı Kriging with
External Drift analizinin seyrek gözlemlerin olduğu yerlerin yağış
haritalarının oluşturulmasına yardımcı bir yöntem olduğunu göstermiştir. 

Anahtar Kelimeler

Yağış, Yükseklik, Jeoistatistik, Kriging with External Drift

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