How to define relativeElevation reference and generate relativeElevation maps in CWatM

[YSQ0109]

Hi everyone,

We are currently preparing input data for a basin-scale study using CWatM, and we have a question about the critical terrain variable dzRel (relative elevation above flood plains).

We’d be grateful for clarification on:

1. Reference elevation definition:
   What is the zero reference point used to calculate dzRel within a grid cell?
   (e.g., is it relative to the minimum elevation within the cell?)

2. Data generation methodology:
   If we need to create 30 arc-second dzRel maps for a basin, what recommended methodology or tools/scripts should we use to calculate the elevation percentiles (e.g., dzRel0001 to dzRel0100)?

This information would help us prepare accurate input data consistent with the CWatM structure.

Thank you very much for your support!