pathways

pathways

PyAERMOD Pathway dataclasses — Control, Meteorology, Output, and Event pathways.

Also contains enums used across multiple pathways (TerrainType, PollutantType, SourceType) and the chemistry-options cluster (ChemistryMethod, OzoneData, ChemistryOptions).

This module is an internal implementation detail. Public imports should go through :mod:pyaermod.input_generator (the backwards-compatible facade) or :mod:pyaermod.api.

TerrainType

Bases: Enum

AERMOD terrain types

PollutantType

Bases: Enum

Common pollutant types

SourceType

Bases: Enum

AERMOD source types

ChemistryMethod

Bases: Enum

AERMOD NO2 chemistry conversion methods.

OzoneData dataclass

Ozone data for NO2 chemistry options.

Provide either an hourly ozone file, a uniform value, or sector-dependent values.

Parameters:

Name	Type	Description	Default
ozone_file	str	Path to hourly ozone data file.	None
uniform_value	float	Uniform ozone concentration in ppb.	None
sector_values	dict	Mapping of sector index to ozone value in ppb.	None

ChemistryOptions dataclass

AERMOD NO2 chemistry configuration.

Controls the NO2-to-NOx conversion method used in AERMOD. Requires pollutant to be NO2.

Parameters:

Name	Type	Description	Default
method	ChemistryMethod	Chemistry algorithm (OLM, PVMRM, ARM2, GRSM).	ARM2
ozone_data	OzoneData	Ozone data for OLM/PVMRM/GRSM methods.	None
default_no2_ratio	float	Default in-stack NO2/NOx ratio (0-1). Default 0.5.	0.5
olm_groups	list of SourceGroupDefinition	Source groups for OLM method.	list()
nox_file	str	NOx background file (GRSM only).	None

ControlPathway dataclass

AERMOD Control (CO) pathway configuration

Defines overall model behavior, pollutant type, averaging periods, and other global settings.

to_aermod_input

to_aermod_input() -> str

Generate AERMOD CO pathway text

MeteorologyPathway dataclass

AERMOD Meteorology (ME) pathway

Defines meteorological data files and processing options.

AERMOD requires five mandatory ME keywords: SURFFILE -- path to the .sfc file PROFFILE -- path to the .pfl file SURFDATA -- surface station ID + start year UAIRDATA -- upper-air station ID + start year PROFBASE -- base elevation (m MSL) of the profile data

to_aermod_input

to_aermod_input() -> str

Generate AERMOD ME pathway text

OutputPathway dataclass

AERMOD Output (OU) pathway

Controls output file generation and formats.

to_aermod_input

to_aermod_input() -> str

Generate AERMOD OU pathway text

EventPeriod dataclass

A single AERMOD event period definition.

EventPathway dataclass

AERMOD Event (EV) pathway.

Defines specific time periods for event-based processing. Written as a separate file referenced by EVENTFIL in the CO pathway.

add_event

add_event(event: EventPeriod)

Add an event period.

to_aermod_input

to_aermod_input() -> str

Generate AERMOD EV pathway text.