Summary of the article on Stomatal Resistance in CLM5:

## Stomatal Resistance in CLM5

### Medlyn Stomatal Conductance Model
- CLM5 calculates stomatal conductance using the Medlyn stomatal conductance model, which is based on net leaf photosynthesis, leaf-to-air vapor pressure difference, and CO2 concentration at the leaf surface.
- This is a change from previous versions of CLM, which used the Ball-Berry conductance model.

### Stomatal Resistance Equation
- The equation for leaf stomatal resistance (rs) is:
1/rs = gs = g0 + 1.6(1 + g1/sqrt(Ds)) * An/(cs/Patm)
- Where gs is stomatal conductance, g0 is the minimum stomatal conductance, An is net photosynthesis, cs is CO2 partial pressure at the leaf surface, Patm is atmospheric pressure, and Ds is the leaf-to-air vapor pressure difference.
- g1 is a plant functional type (PFT) dependent parameter, as shown in Table 2.9.1.

### Resistance Conversion
- Stomatal resistance is converted from s m2 μmol^-1 to s m^-1 using the equation:
1 s m^-1 = 1x10^-9 Rgas * θatm/Patm μmol^-1 m^2 s
- Where Rgas is the universal gas constant and θatm is the atmospheric potential temperature.