Quality and Homogeneity Analysis of Precipitation Data in North Cyprus

2018-09-14
Yanmaz, Ali Melih
Akıntuğ, Bertuğ
This study aims to reveal procedures for testing and creating a set of complete, quality-controlled, and homogeneous precipitation data sets in North Cyprus. Database involves 37 daily precipitation series which are uniformly distributed throughout the study area with observation periods ranging from 1976 to 2015. As a first step of the procedures, the estimation of the missing values is carried out considering a range of distances with various estimation methods based on neighboring stations. Secondly, the quality assessment of the complete series is performed in terms of detection of unreasonable values and outliers. Thirdly, the two-step approach including the computation of four homogeneity methods and classification of the results is used to check the presence of inhomogeneities in series. As a result of applied procedures, the outliers exceeding the threshold value at monthly scale are observed as expected particularly in summer and early autumn covering the hot and dry periods. Additionally, some stations named as Mehmetçik and Boğaz are flagged as discordant according to the discordancy measures relying on L-moment ratios. In homogeneity analysis, daily precipitation series are analyzed through the testing variables such as, total annual precipitation, monthly maximum precipitation, annual wet days, and seasonal total precipitation. Tatlısu, Yeşilırmak, and Çayönü stations are found as inhomogeneous based on the four absolute homogeneity tests and in conclusion, 33 out of 37 precipitation stations are assessed and proven to be reliable.

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Citation Formats
A. M. Yanmaz and B. Akıntuğ, “Quality and Homogeneity Analysis of Precipitation Data in North Cyprus,” Çeşme-İzmir, Turkey, 2018, p. 1, Accessed: 00, 2021. [Online]. Available: https://hdl.handle.net/11511/74589.