Hi all,
I am currently working on replacing the soil organic matter variable (ORGANIC) in CLM5.0 surfdata.
However, the dataset does not provide ORGANIC directly. It provides:
Based on my understanding, ORGANIC represents the density of soil organic matter (SOM). Therefore, I derived the following conversion formula:
ORGANIC (kg/m³) = OC (g/100g) × BD (g/cm³) × 10 / 0.58
Where:
Thank you very much for your time and help.

I am currently working on replacing the soil organic matter variable (ORGANIC) in CLM5.0 surfdata.
However, the dataset does not provide ORGANIC directly. It provides:
- Soil organic carbon (OC): unit = g/100g (mass content of organic carbon in fine earth fraction)
- Bulk density (BD): unit = g/cm³ (oven dry)
Based on my understanding, ORGANIC represents the density of soil organic matter (SOM). Therefore, I derived the following conversion formula:
ORGANIC (kg/m³) = OC (g/100g) × BD (g/cm³) × 10 / 0.58
Where:
- 10 converts OC from g/100g to g/kg
- 0.58 assumes that SOM contains ~58% carbon (i.e., SOM = OC / 0.58) , see surfdata.nc like figure1
- Is this conversion (especially using the 0.58 factor) widely accepted in CLM5.0 data preprocessing practices?
- Has anyone used the same dataset or a similar one? How did you handle the conversion?
Thank you very much for your time and help.
