Welcome to the ERTH 435, Boundary Layer Meteorology, public webpage for the Spring 2025 semester.
The instructor will try to update this page every few days during the semester.

Cumulus clouds at the top of the atmospheric boundary layer over the M2HATS field site on 24 July 2023, Photo by S. D. Mayor.

Spring 2025 Lectures: MWF, 9:00 - 9:50 AM.

Weds., 22 Jan., Introduction: mean structure and composition of the atmosphere, and the importance of the planetary boundary layer.
Fri., 24 Jan., Definition of a fluid, stress and strain, Cauchy stress tensor, dynamic viscosity.
Mon., 27 Jan., Surface and body forces, partial derivatives, no-slip condition, laminar Couette flow
Weds., 29 Jan., Derivation of linear velocity profile in laminar Couette flow without pressure gradient.
Fri., 31 Feb., Derivation of laminar Couette flow with pressure gradient and the parabolic velocity profile.
Mon., 3 Feb., Incompressible mass continuity eqn. and Blasius laminar boundary layer over a smooth flat plate and the transition to turbulence.
Weds., 5 Feb., Concept of a parcel (system, boundary, state, etc.), ideal gas law, adiabatic expansion and compression, dry adiabatic lapse rate.
Fri., 7 Feb., First law of thermodynamics, adiabatic process, Poisson's Equation, and potential temperature.
Mon., 10 Feb., The effect of water vapor on air density, and virtual temperature and virtual potential temperature.
Weds., 12 Feb., Static stability: unstable, neutral, stable. Environmental and process lapse rates.
Fri., 14 Feb., Dynamic stability: Reynolds number: the ratio of inertial forces to viscosity. Laminar and turbulent flow.
Mon., 17 Feb., How shear-driven and buoyancy driven boundary layers both generate mixed layers with neutral environmental lapse rates.
Weds., 19 Feb., Characteristics of turbulence, L. F. Richardson's conceptual model of energy cascade, Begin Kolmogorov's approach to a quantiative model
Fri., 21 Feb., Variance and the Kolmogorov inertial subrange hypothesis. Power law functions and Buckingham Pi Theorem
Mon., 24 Feb., Flux-gradient relationships at the molecular level: Fourier's law of heat condition, Fick's law of diffusion, and Newton's law of viscosity.
Weds., 26 Feb., Reynolds decomposition, perturbations, turbulent kinetic energy, variance, covariance, correlation.
Fri., 28 Feb., Then, Prandtl's mixing length hypothesis and covariance: turbulent fluxes of heat, momentum, and trace gases.
Mon., 3 Mar., Conversion of kinematic fluxes to true fluxes.
Weds., 5 Mar., Review contributions of 6 of 12 names discussed so far this semester.
Fri., 7 Mar., Review contributions of 6 of 12 names discussed so far this semester.
Mon., 10 Mar., Quiz #1. Then discussion of the free atmosphere. Geostrophic balance and geostrophic wind
Weds., 12 Mar., Discussion of friction, free atmosphere versus "friction layer". Then begin diurnal cycle of the atmospheric boundary layer (ABL).
Fri., 14 Mar., Continue the diurnal cycle of the ABL and balanced flows (geostrophic and Ekman flows).
Mon., 17 Mar., Spring break. No classes.
Weds., 19 Mar., Spring break. No classes.
Fri., 21 Mar., Spring break. No classes.
Mon., 24 Mar., Continue the diurnal cycle of the ABL and (geostrophic and Ekman flows). Also, entrainment and inversion layer.
Weds., 26 Mar., Lecture on balanced flows: antitriptic, geostrophic, inertial, gradient, and Ekman flows.
Fri., 28 Mar., Quiz 2.
Mon., 31 Mar., César Chávez Day (observed)
Weds., 2 Apr., The importance of Boundary Layer Meteorology (1, 2) cellular structure of free convection.
Fri., 4 Apr., Quiz 3. Finish The importance of Boundary Layer Meteorology (3 - 11) and begin characteristics of the stable boundary layer
Mon., 7 Apr., Review of energy transfer processes: Conduction, radiation, convection, and "latent heat".
Weds., 9 Apr., Tour of Chapter 7: Surface energy budget. Review: microlayer, effective turbulent heat flux, energy balance budget models
Fri., 11 Apr., Quiz 4. Discussion of aerosol features in the REAL images from M2HATS: Turbulent coherent structures in the sheared CBL.
Mon., 14 Apr., Begin Atmospheric surface layer. K-theory, exchange coefficients, friction velocity, and begin derivation of the log-wind profile.
Weds., 16 Apr., Complete derivation of log-wind profile and equations 1.13 - 1.17 in Kaimal & Finnigan.
Fri., 18 Apr., Roughness length, displacement height, discussion of similarity theory
Mon., 21 Apr., Discussion of Richardson number, the Obukhov length, z/L, Monin-Obukhov Similarity Theory (MOST) and begin the stable boundary layer,
Weds., 23 Apr.,
Fri., 25 Apr.,
Mon., 28 Apr.,
Weds., 30 Apr.,
Fri., 2 May,
Mon., 5 May,
Weds., 7 May,
Fri., 9 May,
Weds., 14 May, Final comprehensive exam.

Dr. Mayor's page

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