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

Abstract

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.

Keywords

• precipitation,elevation,geostatistics

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

Abstract

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. 

Keywords

• Yağış,Yükseklik,Jeoistatistik,Kriging with External Drift

References

1. Apaydin, H., Anli, A.S., Ozturk, F. (2011). “Evaluation of Topographical and Geographical Effects on Some Climate Parameters in the Central Anatolia Region of Turkey”, International Journal of Climatology, Vol.31, Pp. 1264–1279.
2. Aydın, O., Çiçek, İ. (2013). “Ege Bölgesi'nde Yağışın Mekânsal Dağılımı”, Coğrafi Bilimler Dergisi, Vol. 11, No. 2, Pp. 101–120.
3. Aydin, O.; Çiçek, İ. (2015). Geostatistical Interpolation of Precipitation in Turkey, Lambert Academic Publishing, Saarbrucken, Germany.
4. Bivand, R.S., Pebesma, E., Gómez-Rubio, V. (2008). Applied Spatial Data Analysis with R (use R!). 1. Edition, Springer, London.
5. Buytaert, W., Celleri, R., Willems, P., De Beivre, B., Wyseure, G. (2006). “Spatial and Temporal Rainfall Variability in Mountainous Areas: A case Study from the South Ecuadorian Andes”, Journal of Hydrology, Vol. 329, Pp. 413–421.
6. Boer, E.P.J., Beurs, K.M., Hartkamp, A.D. (2001). “Kriging and Thin Plate Splines for Mapping Climate Variables”, International Journal of Applied Earth Observation and Geoinformation, Vol. 3 No. 2, Pp. 146–154.
7. Daly, C., Gibson, W.P., Taylor, G.H., Johnson, G.L., Pasteris, P. (2002). “A knowledge-Based Approach to the Statistical Mapping of Climate”, Climate Resarch Vol. 22, Pp. 99–113.
8. Darkot, B., Tuncel, M. (1988). Geography of Aegean Region. Istanbul University Oublishing/Institute of Geography Publishing, 2. Edition, İstanbul.

9. Deutsch, C., Journel, A. (1998). GSLIB: Geostatistical Software Library and User’s Guide. 2. Edition, New York: Oxford University Press.
10. Diodato, N. (2005). “The Influence of Topographic Co-variables on the Spatial Variability of Precipitation Over Small Regions of Complex Terrain”, International Journal of Climatology, Vol. 25, No. 3, Pp. 351–363.
11. Goovaerts, P., (1997). Geostatistics for Natural Resources Evaluation. New York: Oxford University Press.
12. Goovaerts, P. (2000). “Geostatistical Approaches for Incorporating Elevation into the Spatial Interpolation of Rainfall”, Journal of Hydrology, Vol. 228, Pp. 113–129.
13. Hession, S.L., Moore, N. (2011). “A spatial Regression Analysis of the Influence of Topography on Monthly Rainfall in East Africa”, International Journal of Climatology, Vol. 31, Pp. 1440–1456.
14. Hevesi, J.A., Flint, A.L., Istok, J.D. (1992). “Precipitation Estimation in Mountainous Terrain Using Multivariate Geostatsitics. Part I: Structural Analysis”, Journal of Applied Meteorology and Climatology, Vol. 31, Pp. 661–676.
15. Hofierka, J., Parajka, J., Mitasova, H., Mitasi, L. (2002). “Multivariate Interpolation of Precipitation Using Regularized Spline with Tension”, Transactions in GIS, Vol. 6, No. 2, Pp. 135–150.
16. Hohn, M.E. (1998). Geostatistics and Petroleum Geology. Kluwer Academic Publishers, Dordrecht.
17. Hutchinson, M.F. (1998). Interpolation of Rainfall Data with Thin Plate Smoothing Splines-part II: Analysis of Topographic Dependence. Journal of Geographic Information and Decision Analysis, Vol. 2, No. 2, Pp. 152–167.
18. Isaaks, E., Srivastava, R. (1989). An Introduction to Applied Geostatistics. Oxford University Press, New York.
19. Kieffer Weisse, A., Bois, P.H. (2002). “A Comparison of Methods for Mapping Statistical Characteristics of Heavy Rainfall in the French Alps: The Use of Dairly Information”, Hydrological Sciences, Vol. 47, No. 5, Pp. 739–752.
20. Koçman, A. (1993). Turkey Climate. Aegean University Faculty of Arts Geography Branch, İzmir.
21. Kyriakidis, P.C., Kim, J., Miller, N.L. (2001). “Geostatistical Mapping of Precipitation from Rain Gauge Data Using Atmospheric and Terrain Characteristics”, Journal of Applied Meteorology, Vol. 40, Pp. 855–1877.
22. Lloyd, C.D. (2005). “Assessing the Effect of Integrating Elevation Data into the Estimation of Monthly Precipitation in Great Britain”, Journal of Hydrology, Vol. 308, Pp. 128–150.
23. Lloyd, C.D. (2010). “Nonstationary Models for Exploring and Mapping Monthly Precipitation in the United Kingdom”, International Journal of Climatology, Vol. 30, Pp. 390–405.
24. Mair, A., Fares, A. (2011). “Comparison of Rainfall Interpolation Methods in a Mountainous Region”, Journal of Hydrologic Engineering, Pp. 371–383.
25. Moral, F.J. (2010). “Comparison of Different Geostatistical Approaches to Map Climate Variables: Application to Precipitation”, International Journal of Climatology, Vol. 30, Pp. 620–631.
26. Pardo-Igúzquiza, E. (1998). “Comparison of Geostatistical Methods for Estimating the Areal Average Climatological Rainfall Mean Using Data of Precipitation and Topography”, International Journal of Climatology, Vol. 18, Pp. 1031–1047.
27. Pebesma, E.J., Wesseling, C.G. (1998). Gstat, A Program for Geostatistical Modelling, Prediction and Simulation. Computers & Geosciences, Vol. 24, No. 1, Pp. 17–31.
28. Pebesma, E.J. (2004). “Multivariable Geostatistics in S: The Gstat Package”, Computer&Geosciences, Vol. 30, Pp. 683–691.
29. Peucker, T.K. (1980). “The Impact of Different Mathematical Approaches to Contouring”, Cartographica, Vol. 17, Pp. 73–95.
30. Phillips, D.L., Dolph, J., Marks, D. (1992). “A Comparison of Geostatistical Procedures for Spatial Analysis of Precipitation in Mountainous Terrain”, Agricultural and Forest Meteorology, Vol. 58, No. 1–2, 119–141.
31. Qing, Y., Zhu-Guo, M., Liang, C. (2011). “A Preliminary Analysis of the Relationship Between Precipitation Variation Trends and Altitude in China”, Atmospheric and Oceanic Science Letters, Vol. 4, No. 1, Pp. 41–46.
32. Silva, W.M., Simões, S.J. (2014). Spatial Intra-annual Variability of Precipitation Based on Geostatistics: A Case Study for the Paraiba Do Sul Basin, Southeastern Brazil. International Journal of Geosciences, Vol. 5, Pp. 408–417.
33. Tobin, C., Nicotina, L., Parlange, M.B., Berne, A., Rinaldo, A. (2011). “Improved Interpolation of Meteorological Forcings for Hydrologic Applications in a Swiss Alpine Region”, Journal of Hydrology, Vol. 401, Pp. 77–89.
34. Wilmott, C.J. (1982). “Some Comments on the Evaluation of Model Performance”, Bulletion of the American Meteorological Society, Vol. 63, Pp. 1309–1313.
35. Wotling, G., Bouvier, Ch., Danloux, J., Fritsch, M.J. (2000). “Regionalization of Extreme Precipitation Distribution Using the Principal Components of the Topographical Environment”, Journal of Hydrology, Vol. 233, No. 1–4, Pp. 86–101.
36. Yin, Z.Y., Zhang, X., Liu, X., Colella, M., Chen, X. (2008). “An Assessment of the Biases of Satellite Rainfall Estimates Over the Tibetan Plateau and Correction Methods Based on Topographic Analysis”, Journal of Hydrometeorology, Vol. 9, Pp. 301–417.