Theory & Concepts for Atmospheric Dispersion

[ Home | Homework | ]


Overview

Spreadsheet comparing features of AERMOD, HYSPLIT, CALPUFF, & CMAQ.   (Draft, Aug 2018)

  1. Quick overview of turbulence theory, boundary-layers & diffusion theory
    (See Stull, 2017, Practical Meteorology (PrMet),
    Chapter 18 Atmospheric Boundary Layers &
    Chapter 19 Pollutant Dispersion). 

    The notation below refers to section numbers in those chapters.
    1. PrMet 19.0 - 19.2.  Intro, terminology, air qual standards. Also  BC AirQual Stds.
    2. Discussion: Passive tracers.   Role of turbulence vs. molecular diffusion.
    3. Superposition of eddies.  Shear generationBuoyant generation.
      Deeper convection1. Deeper convection2.
    4. Discussion of spectrum of eddy sizes.  Richardson's poem.  ScanSet A p3
    5. Turbulent timeseries.  
    6. Turbulence statistics BCMoE talk 2017 p39-60  ; & [PrMet 18.6 Turb (but not last page)] .
    7. Smoke is emitted into Atmos. Boundary Layers (ABL), and ABLs are often turbulent.
    8. PrMet 18.0-18.5 ABLs .
    9. PrMet 19.3 stable vs neutral vs unstable ABLs.  Pasquill-Gifford
  2. Gaussian Plumes
    1. PrMet 19.4.1.  Plume snapshot vs time average.
    2. From 1-D Gaussian puff (ScanSet B) to 3-D Gaussian plumes (ScanSet C)
      (and their relationship to AERMOD and HYSPLIT)
    3. Taylor's statistical theory (ScanSet D)
    4. Meaning and widespread use of Lagrangian autocorrelation R
    5. Sigma-y and sigma-z
    6. Applications
    7. Homework:  Gaussian plume for neutral PBL.
  3. Dispersion in Convective Boundary Layers (Deardorff)
    1. Similarity theory overview from Intro to BL Meteorology chapter 9 (ScanSet E),
      and the Handbook of similarity functions
    2. Movie of Willis & Deardorff convection tank experiments (download first, then play)
    3. Convective similarity for pollutant dispersion (ScanSet F)
    4. Interpretation of dimensionless variable "X"
    5. Stull's fit to Deardorff convective dispersion (PrMet 19.7)
    6. Homework: Deardorff smoke dispersion in convective PBL
  4. Plume Rise
    1. Briggs & Weil plume rise derivations (ScanSet G)
    2. .
  5. Lagrangian particle dispersion
    1. Concept of Advection by the mean wind.  Banff movie (download, then play) & COMET demo
    2. Trajectories vs streamlines vs streaklines
    3. Eqs. used in Hysplit. (see BAMS paper eqs 2 & 3 and Hysplit arl-224 Tech Memo in the HYSPLIT section of this course)
    4. Advection equation: (See BAMS paper eq 1).   Demo with advection worksheet
    5. Turbulent dispersion of particles
      1. Langevin eq. vs. turbulent dispersion (See BAMS supplement)
      2. Similarity eqs. for sigma-u,v,w .   (& Homework)
      3. Write your own Lagrangian particle model - 1-D
    6. Turbulence kinetic energy (TKE)
    7. Turbulent dispersion of puffs
  6. XXX
    1. .
    2. .
  7. XXX



Other Info





[ Home | Homework | ]

http://www.eos.ubc.ca/courses/atsc507/ADM/
Copyright 2016, 2018 by Roland Stull.