Different interpolation methods used in the production of isarithmic maps: Case of temperature values analysis

In this research, Isarithmic maps, one of the thematic map types, were studied in detail. Subjects such as categories, brief history, advantages, usage areas, interpolation methods used in the determination of intermediate values for production, map design and symbolization of isarithmic maps are included. Isarithmic maps were created by using temperature data obtained from meteorology, which is one of the usage areas of isarithmic maps. Annual average temperature values for the years 1926-2018 were obtained from the General Directorate of Meteorology (MGM). 82 station points were used. 61 of them were determined as control points and 21 as interpolation points. Various interpolation methods were used to determine the annual mean temperature values for the interpolation points. There are 6 interpolation methods used. These methods are; inverse distance weighted, triangulation and linear, modified Shepard, natural neighborhood, minimum curvature, radial basis function (RBF). The methods used were evaluated according to the statistical results. The methods were compared according to the maximum/minimum values, range value and mean square error (MSE) values. According to this comparison, it was seen that the most suitable method was triangulation and linear method. The lowest accuracy was obtained from the modified Shepard method. The major deficiency in the literature part about isarithmic maps, which is frequently used, has been eliminated with this thesis study. It is thought that isarithmic maps produced for temperature data in the application part will be useful for many study areas. Nowadays, it is seen that the temperature values have changed a lot, global warming has increased and the natural balance has been disturbed accordingly. Therefore, studies on this subject have been increased and necessary precautions have been started to be taken.