August-Roche-Magnus approximation [Pa]

from pg.38 of Lu, N. and J.W. Godt, 2013. Hillslope Hydrology and Stability. Cambridge University Press. 437pp.)
[Pa=N/m²] R²=1 for -30°C =< T =< 50°C

\[ e_s=610.49 \cdot \exp\frac{17.625\cdot T_C}{T_C+243.04}, \]

where \(T_C\) is air temperature in degrees celcius.

es.obs <- read.csv('es.csv',skip=1)

es.obs %>% ggplot() +
  geom_point(aes(Temperature,saturation.vapour.pressure.over.liquid.water)) +
  geom_function(fun = function(x) 610.49*exp(17.625*x/(x+243.04))) +
  xlim(c(-50,50)) +
  coord_flip()