Streamflow map of the Eastern Black Sea Region, Turkey

The purpose of this study is to generate a streamflow map for the coastal part of the Eastern Black Sea Region, which is located in the north-east of Turkey. The topographic structure of the region is an obstacle in terms of the number of observation gauges. In order to determine spatial variation of flow and to estimate flow on any ungauged points in the region, interpolation between gauged and ungauged points is applicable. For this purpose, any hydrological models, which depend on large meteorological datasets, can be used. However, in this study, ordinary and universal kriging as geostatistical interpolation methods are used to interpolate mean annual flow depth over the study area; thus, flow values on ungauged points can be easily estimated. Kriging methods are compared with simple regression based on the relationship between flow data and basin area. Calibration results of the observed and estimated flow depths for ordinary and universal kriging methods are satisfactory; the determination coefficients are found to be 0.84 and 0.87, respectively. Besides, the validation results show that the performance of kriging methods is superior to that of the regression model. (C) 2018 Sharif University of Technology. All rights reserved.