Converting Soil Water Content from mmH2O to unitless

[LJ]

Hi all,

I want to do some comparisons between modeled soil moisture with remote sensing soil moisture data. The remote sensing data comes in mm/mm or mm/m units (which are essentially unitless).

I would like to convert the SWmm in output.hru to the same unit. What is the depth I should be using in the conversion? Is it maximum depth of soil layers?

Regards,

LJ

[LJ]

Let me put my question in another way:

How exactly is the SWmm in output.sub calculated and what is the mm unit referring to?

Typically the soil water content or soil moisture is measured or quantified as Length of Water Column/Length of Soil Layer depth so the result values would be unitless or something like mm/m which is essentially unitless with a multiplier.

I am just unsure if this is also the case for SWAT soil water content output since there is little information given in the I/O document and theoretical document.

[Omid mohammadi]

You need to modify the codes to print SW at the same depth as RS.

[Omid mohammadi]

Hi,

You need to modify the codes to print the SW at the same depth as RS. I have already done this work. Let me know if you face any problems.

On Sunday, June 19, 2022 at 1:41:23 a.m. UTC+4:30 LJ wrote:

[LJ]

Hi,

Thank you for your reply. Unfortunately, It is not viable for my work to make modifications to the swat model codes rather than doing calculations externally.

What is the default depth that SWAT is using? It would be very helpful for me to know this since I can just use that to convert the soil water content from mm to unitless (mm/mm).