I am trying to calculate the volume of several DEMs in order to obtain elevation and volume changes. I have pixels of 1x1 each one associated to an elevation. I used several methods but non of them gave me the same results and I am starting to despair.
First method: I multiply the total sum of the dem elevation, obtained in the statistics of it, by the area of one pixel. I subtract two consecutive DEMs in order to obtain the total volume change.
Second method: I use the Volume and Area Calculator of the 3D Analysis Tool. I subtract two consecutive DEMs in order to obtain the total volume change.
Third method: I use the Cut/Fill tool in order to obtain the gain/losses of volume between to consecutive DEMs. Total gain minus total losses will give me the total change. Forth method. I subtract to consecutive DEMs in the raster calculator and I obtained the volume of this new raster using the pixel method (first one) and using the Volume Calculator (second one).
Non of these methods gave me the same results and I am really worry about it. I will really appreciate if someone knows how to obtain the volume of a DEM.