I created a toy raster with the following values:
30 30 30 30
30 0 0 30
30 0 0 30
30 30 30 30
and a projection of NAD_1983_Albers, with 30x30 m cells (to match my DEM motivating the issue). I then ran Surface Volume (3D) with the following settings:
Reference Plane: BELOW
Plane Height: 30
Z Factor: 0.01 **Note I was not allowed to change this value in ArcMap; it was interpreted by default from the projection.
Based on my multiple open topics, here are results I could expect given those inputs:
- plane height is in meters, z factor is m/cm: volume = (30 m)*(30 m)*(30 m)*(4 cells) + (30 m)*(30 m)*(29.7 m)*(12 cells) = 428,760 m^3
- plane height is in centimeters, z factor is m/cm: volume = (30 m)*(30 m)*(0.3 m)*(4 cells) = 1,080 m^3
- plane height is in meters, z factor is in cm/m: volume = (30 m)*(30 m)*(30 m)*(4 cells) = 108,000 m^3
- plane height is in centimeters, z factor is in cm/m: volume = (30 m)*(30 m)*(0.3 m)*(4 cells) = 1,080 m^3
The actual results are... 241,650 somethings^3.
My conclusion: either I dont understand what this tool is doing (and my topics asking for more explanation are well-founded), my experiment was flawed, or there's something very wrong with the tool.
If anyone can shed some light on the topic, I would be really appreciative.