Estimation Of Turkey's Long-Term Average Temperature (°C) With Three Different Interpolation Methods

Abstract

In this study, Turkey's long-term monthly average temperatures were estimated using three different interpolation methods. Temperatures were estimated using the latitude-longitude characteristics of neighboring measuring stations and Inverse Distances Weighted (IDW), Kriging and Radial Basis Function (RBF) methods. The methods were applied with ArcMAP program under ArcGIS software. Two different interpolation parameters were used in the study. These are Latitude (Degrees) and Longitude (Degrees). The data are between 1981-2020 and were obtained from the General Directorate of Meteorology. In the study, 81 province measurement stations were used to represent Turkey. In total, 75 of the data of 972 (81 stations x 12 months) was used in the training phase. And the 25 of the data of 972 (81 stations x 12 months) was used in the testing phase. The test stations used were randomly selected and the predictions obtained during the testing phase were compared with the observed data. In comparisons, Root Mean Squared Error (RMSE), Mean Absolute Error (MAE) and Coefficient of Determination (R2) were used. When the results obtained are examined, the best result is estimated at Ardahan (Kriging, RMSE:30,22 degrees C, MAE:5,29 degrees C, R2:0,988) station, and the worst result is estimated at Aksaray (IDW, RMSE:121,94 degrees C, MAE:3,48 degrees C, R2:0,375) station. When the best results of the methods are examined, the best estimation for the IDW method was found at Sanliurfa (RMSE:27,21 degrees C, MAE:4,02 degrees C, R2:0,851) station, for the Kriging method the best estimation was found at Ardahan (RMSE:30,22 degrees C, MAE:5,29 degrees C, R2:0,988) station, and for the RBF method the best estimation was found at Sirnak (RMSE: 0,47 degrees C, MAE: 0,43 degrees C, R2: 0,998) station. The worst results were found at Aksaray (RMSE:121,94 degrees C, MAE:3,48 degrees C, R2:0,375) station for IDW method, at Tunceli (RMSE:48,44 degrees C, MAE:6,5 degrees C, R2:0,986) station for Kriging method, and at Tunceli (RMSE:7,85 degrees C, MAE:7,86 degrees C, R2:0,521) station for RBF method.GEOMATI