Resistance

atmospheric_canopy_resistance(lai_eff, stress_rad, stress_vpd, stress_temp, rs_min=70, rcan_max=1000000.0)

Computes canopy resistance excluding soil moisture stress.

\[r_{canopy,0}=\left(\frac{r_{s,min}}{I_{lai, eff}}\right)\cdot \left(\frac{1}{S_{T} \cdot S_{V} \cdot S_{r}}\right)\]

Parameters

lai_eff (float) – effective leaf area index, \(I_{lai,eff}\) [-]
stress_temp (float) – stress factor for air temperature, \(S_{t}\) [-]
stress_vpd (float) – stress factor for vapour pressure deficit, \(S_{v}\) [-]
stress_rad (float) – stress factor for radiation, \(S_{r}\) [-]
rs_min (float) – Minimal stomatal resistance, \(r_{s_min}\) [sm-1]
rcan_max (float) – Maximum stomatal resistance, \(r_{can_max}\) [sm-1]

Returns

r_canopy_0 – atmospheric canopy resistance, \(r_{canopy,0}\) [sm-1]

Return type

float

Examples

>>> import ETLook.resistance as res
>>> res.atmospheric_canopy_resistance(0.9, 0.4, 0.9, 0.94)
229.839768846861

canopy_resistance(r_canopy_0, stress_moist, rcan_max=1000000.0)

Computes canopy resistance.

\[r_{canopy}=\frac{r_{canopy,0}}{S_{m}}\]

Parameters

r_canopy_0 (float) – Atmospheric canopy resistance, \(r_{canopy_0}\) [sm-1]
stress_moist (float) – stress factor for root zone soil moisture, \(S_{m}\) [-]
rcan_max (float) – Maximum stomatal resistance, \(r_{can_max}\) [sm-1]

Returns

r_canopy – canopy resistance, \(r_{canopy}\) [sm-1]

Return type

float

Examples

>>> import ETLook.resistance as res
>>> res.canopy_resistance(218, 0.8)
272.5

soil_resistance(se_top, land_mask=1, r_soil_pow=-2.1, r_soil_min=800)

Computes soil resistance.

\[r_{soil}=r_{soil, min}\cdot \left(S_{e,top}\right)^{a}\]

Parameters

Returns

r_soil – soil resistance, \(r_{soil}\) [sm-1]

Return type

float

Examples

>>> import ETLook.resistance as res
>>> res.soil_resistance(se_top=0.9)
998.1153098304111