Overview*

1. A research-grade dispersion model for estimating near-road pollutant concentrations from near-surface emissions from roads and other line sources.
2. Appropriate for flat roadways (no surrounding major complexities).
3. Handles intersections and crossing roads.
4. Handles curved roads.
5. Handles minor complexities often associated with the roads themselves: (noise and vegetative barriers, depressed roadways, etc).
6. Written in fortran.  Tested with gfortran compiler. 
   

Used For* 

• Risk assessments and health studies related to pollutants measured at receptors very near the source line/roadway.
• NOT appropriate for regulatory applications (e.g. NAAQS compliance and enforcement, NSR/PSD permitting, PM Hot-spot Conformity Analyses, SIP analysis, etc) because it has not undergone the extensive testing and comprehensive evaluation for such regulatory use.
  

* from https://www.cmascenter.org/r-line/

Model Dynamics, Physics & Parameterizations*

1. uses a steady-state Gaussian formulation that is designed to simulate line type source emissions (e.g. mobile sources along roadways) by numerically integrating point source emissions.  (beta option includes algorithms for analytical solution)
   
2. contains new (field study and wind tunnel based) formulations for the vertical and lateral dispersion rates,
   
3. also simulates low-wind-speed meander conditions,
   
4. includes Monin-Obukhov similarity profiling of winds near the surface
   
5. selects plume-weighted winds for transport and dispersion calculations.
   
6. utilizes the surface meteorology provided by the AERMET meteorological data preprocessor
   
7. includes user-friendly input requirements such as simplified road-link specifications.
   

Code sources

1. https://www.cmascenter.org/r-line/
   
2. Also uses AERMET (see more info in the AERMOD portion of this course).
3. Source download: https://www.cmascenter.org/download/forms/step_1.cfm
   

Resources

1. Users manual: https://www.cmascenter.org/help/documentation.cfm?model=r-line
   
2. 
   

Model running resources and tips

http://www.eos.ubc.ca/courses/atsc507/ADM/
Copyright © 2018 by Roland Stull.