Aim. Glaciological, geodetic and photogrammetric methods can be distinguished between methods of obtaining data for observations of glaciers. Photogrammetric method refers to the remote sensing methods, so its application for the study of these objects is definitely more reasonable. This is primarily conditioned by the fact that there is no need to work on the body of the glacier, which is very dangerous. In addition, the accuracy of the glaciers volume is satisfies of the glaciologist requirements by this method. The technology of digital surface model constructing of surface glaciers is a fairly significant problem in the implementation stereophotogrammetric method. The choice of DEM setting method is an important step. Defining the parameters of the grid is one of the processes in the case constructing DEM by regular placing grid nodes. The main aim is to optimize grid spacing that will help improve efficiency and adaptability to data processing. Methods. The regular grid with square elementary cell is set to build a digital surface model. Such values as: error of the determining coordinates of points, lengths of lines and error of the area determination, depth and volume of the glacier influence of the elementary cell size. The algorithm for determining the optimal grid spacing involves the following steps: calculating a priori accuracy of the coordinates of points, determining permissible relative errors of glaciers volume, depth and area and calculation of the optimal grid spacing. A priory accuracy of the points coordinates determination the first and obligatory step. Whereas the mean square errors of the determining photogrammetric coordinates of points influence on all following measurements and processes. The second step is setting accuracy of the glaciers volume determination. It is assumed that this error is 1%. The third stage involves consideration the permissible depth of object in a grid cell. The fourth stage of work is calculation of permissible relative error area determination considering relative permissible error and depth of object. The last – fifth step is to calculate the grid spacing. It is defined as the length of the elementary grid cell, taking into account the errors of the areas and side of grid cell. The calculated step can also determine the number and density of grid nodes in which measurements performed on the glaciers surface. Results. The algorithm and the proposed formula for calculating the optimum grid spacing for building DSM of glaciers outputs surfaces. Scientific innovation. For the first time proposed algorithm of optimization grid step of digital surface model in determining volume of glaciers, and other objects. The practical significance. This algorithm will significantly to reduce the time for digital terrestrial stereophotogrammetry data processing and to obtain the value of the surface volume of the Winter and Galindez island glaciers of the Antarctic coast with the corresponding accuracy.
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