Input Files
Gas Chemistry Input File
The YAML input file for atmospheric chemistry consists of five sections:
environmental_conditions: pressure and temperature of individual cells.initial_state: initial species concentrations within the cells.reactions: list of reactions with rate parameters and reaction type.constant_species: species that are part of the reaction mechanism but are assumed constant in time.- E.g., invariant species.
species: list of species names.
For example, given the toy reaction \(A \rightarrow B\), simulation with N cells, one reaction, and three species, we have
yaml
NCAR-version: v1.0
environmental_conditions:
pressure:
evolving: false
initial_value: [P1, ..., PN]
units: Pa
temperature:
evolving: false
initial_value: [T1, ..., TN]
units: K
initial_state:
A:
initial_value: [A1, .., AN]
units: mol m-3
M:
initial_value: [M1, .., MN]
units: mol m-3
reactions:
- coefficients:
products:
B: 1.0
reactants:
A: 1.0
type: ARRHENIUS
constant_species:
- description: tracer-CONSTANT
name: M
species:
- description: A
name: A
- description: B
name: B
A description of the reaction types currently implemented in TChem-atm is presented in Methodology section. In addition, a set of examples of input files is presented under /src/examples/runs/atmopheric_chemistry.
Gas-Aerosol Chemistry Input File
To execute a gas-aerosol case in TChem-atm, one needs an input file with the aerosol mechanisms, aerofile, and a file where scenario particle information is given, inputfile_particles. The aerosol mechanism utilizes a YAML file and follows to the CAMP format. The scenario particle information follows this format:
```yaml particles: initial_state: species_name_1: initial_value: [1.0e-8] species_name_2: initial_value: [1.4e-2] num_concentration: initial_value: [1.3e6]
``
In this structure,species_name_1` denotes the initial concentration of species 1 within a single particle. It's important to note that the initial composition for species 1 is consistent across all particles.
Additionally, to incorporate gas-phase reactions into the simulation, a gas reaction mechanism can be seamlessly integrated into the gas-aerosol case.