I found these two links really helpful, try:

http://blogs.esri.com/esri/arcgis/2010/10/27/understanding-curvature-rasters/

http://www.ian-ko.com/ET_Surface/UserGuide/Raster/ETG_RasterCurvature.htm

At the same time, you may have a look into this paper:

Rana, Sanjay. "Use of plan curvature variations for the identification of ridges and channels on DEM." Progress in spatial data handling. Springer Berlin Heidelberg, 2006. 789-804.

Hope that helps.

you should be classify profile and plan curvature based on the following values:

concave: 0.001 or upper bound value)

Hello!

I was reading this exchange of information and there is something I do not manage to get my hear around. If the reply of Hamid Reza Pourghasemi holds true, negative values should indicate a concave surface.

Yet, from Esri's webpage (http://blogs.esri.com/esri/arcgis/2010/10/27/understanding-curvature-rasters/) fig. 16.20 (profile curvature), a concave curvature should be indicated by positive values. Is that an error on Ersi's webpage part?

From a commonsene standpoint, I would lean to agree with Hamid Reza Pourghasemi...

Best

Dear Alverti

in Plan curvature: Convex (+), Concave (-)

BUT

Profile curvature: Concave (+), Convex (-)

Best

Dear Hamid,

thank you for the clarification.

Best

Gianmarco

Hello,

I have a question related to the profile curvature values.

In an article I was reading (reference provided at the bottom of this question), scholars have found a negative correlation between profile curvature and soil moisture (see articles' pages 274-75).

Now, it is my understanding that (judging from the fact that the correlation is negative) when profile curvature has negative values (i.e., convex), the moisture should be high, and vice versa.

Now, what I am wondering is how can a convex (sloping) terrain hold more moisture than a concave one? May be I am missing something here....

Thanks for any elucidation.

Reference:

Famiglietti, J., Rudnicki, J., & Rodell, M. (1998). Variability in surface moisture content along a hillslope transect: Rattlesnake Hill, Texas. Journal of Hydrology, 210(1-4), 259–281. doi:10.1016/S0022-1694(98)00187-5

Dear researchers, 

Thank you for your response.

The answer given by the Dr. Hamid is for plan and profile curvatures. 

If we use combo-curvature (which is combination of plan and profile curvature how would be the classification ? 

Ramesh for the Combo-curvature, according to ESRI: A positive curvature indicates the surface is upwardly convex at that cell and a negative curvature indicates the surface is upwardly concave at that cell. See this link

http://webhelp.esri.com/arcgisdesktop/9.2/index.cfm?TopicName=Curvature

Strange, in a more recent link the positive profile curvature is a concave cell but I really don’t understand how a convex surface decelerates the flow and  the concave one will accelerate it.

It´s what they are saying in this link … additionaly i’m currently trying to cite someone on this matter and I’m just more confused. I know other software’s use different signs but the logic of the acceleration in a concave cell I still don’t get it!?? Can someone please clarify this to me?

http://desktop.arcgis.com/en/arcmap/10.3/manage-data/raster-and-images/curvature-function.htm

Thanks for the information, I am starting to learn about this topic in order to implemet a methodology in my field (archaeology, rockart) and I find this line really usefull!