Dry Deposition

Model

This is an implementation of a box model used to calculate changes in gas species concentration due to dry deposition.

Running the model

Here's an example of how concentration of different species, such as SO₂, O₃, NO₂, NO, H₂O₂, CH₂O and HNO₃change due to dry deposition.

We can create an instance of the model in the following manner:

using AtmosphericDeposition
using ModelingToolkit
using DifferentialEquations
using EarthSciMLBase
using DynamicQuantities
using ModelingToolkit:t

model = DrydepositionG()

Before running any simulations with the model we need to convert it into a system of differential equations.

sys = structural_simplify(model)
tspan = (0.0, 3600*24)
prob = ODEProblem(sys, [], tspan, []) # default initial concentration of SO₂, O₃, NO₂, H₂O₂, HNO₃, CH₂O
sol = solve(prob,AutoTsit5(Rosenbrock23()), saveat=10.0) # default parameters

which we can plot as

using Plots
plot(sol, xlabel="Time (second)", ylabel="concentration (ppb)", legend=:outerright)
Example block output

Parameters

The parameters in the model are:

parameters(sys) # [iLandUse, z, z₀, u_star, L, ρA, G, iSeason, T, θ]

where iLandUse is the index for the landuse, iSeason is the index for the season, z is the top of the surface layer [m], z₀ is the roughness length [m], u_star is friction velocity [m/s], and L is Monin-Obukhov length [m], ρA is air density [kg/m3], T is surface air temperature [K], G is solar irradiation [W m-2], Θ is the slope of the local terrain [radians].

Let's run some simulation with different value for parameter z. 

@unpack O3,z = sys

p1 = [z=>50]
p2 = [z=>10]
sol1 = solve(ODEProblem(sys, [], tspan, p1),AutoTsit5(Rosenbrock23()), saveat=10.0)
sol2 = solve(ODEProblem(sys, [], tspan, p2),AutoTsit5(Rosenbrock23()), saveat=10.0)

plot([sol1[O3],sol2[O3]], label = ["z=50m" "z=10m"], title = "Change of O3 concentration due to dry deposition", xlabel="Time (second)", ylabel="concentration (ppb)")
Example block output