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photosynthesis (version 2.0.3)

gw2gc: Convert g_c (\(\mu\)mol CO2/m^2/s/Pa) to g_w (\(\mu\)mol H2O /m^2/s/Pa)

Description

Convert g_c (\(\mu\)mol CO2/m^2/s/Pa) to g_w (\(\mu\)mol H2O /m^2/s/Pa)

Convert g_c (umol CO2/m^2/s/Pa) to g_w (umol H2O /m^2/s/Pa)

Usage

gw2gc(g_w, D_c, D_w, unitless)

gc2gw(g_c, D_c, D_w, unitless)

Value

Value with units \(\mu\)mol / (m^2 s Pa) of class units.

Arguments

g_w

conductance to water vapor in units (\(\mu\)mol H2O / (m^2 s Pa)) of class units.

D_c

diffusion coefficient for CO2 in air in units of m^2/s of call units

D_w

diffusion coefficient for H2O in air in units of m^2/s of call units

unitless

Logical. Should units be set? The function is faster when FALSE, but input must be in correct units or else results will be incorrect without any warning.

g_c

conductance to CO2 in units (\(\mu\)mol H2O / (m^2 s Pa)) of class units.

Details

Diffusive conductance to CO2 is generally about ~1.6x that of H2O because of the higher molecular weight. To convert, multiply conductance by the ratio of diffusion coefficients:

$$g_\mathrm{c} = g_\mathrm{w} D_\mathrm{c} / D_\mathrm{w}$$ $$g_\mathrm{w} = g_\mathrm{c} D_\mathrm{w} / D_\mathrm{c}$$

Examples

Run this code
D_c <- set_units(1.29e-05, "m^2/s")
D_w <- set_units(2.12e-05, "m^2/s")
g_c <- set_units(3, "umol/m^2/s/Pa")
g_w <- gc2gw(g_c, D_c, D_w, unitless = FALSE)
g_w

gw2gc(g_w, D_c, D_w, unitles = FALSE)

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