Boundary Layers, Transport and Mixing 2021(MO412M)

A course on transport (of e.g. energy, momentum, water, mass and potential vorticity substance) by turbulence in the atmospheric boundary layer, by radiation and by the large scale planetary waves and eddies in the atmosphere.

This is an optional course (7.5 ects) within the fourth year of the Masters program in "Climate Physics" at the Utrecht University (UU).

Given by Michiel van den Broeke and Aarnout van Delden (a.j.vandelden@uu.nl).

Wednesday, 15:15-17:00:online

Friday, 10:00-12:45: on campus (BBG)

Note: lectures on Friday begin at 10:00 on 7 May, 21, May, 28 May, 4 June, 11 June and 25 June

See Blackboard for the last information

Osiris link:

Boundary Layers, Transport and Mixing

Book

Recommended for part 1 of the course: R.B.Stull: An Introduction to Boundary Layer Meteorology. Kluwer Academic Publishers. 666 p.

Lecture Notes part 2

AtmosphericDynamics[2022]Ch12.pdf

Schedule part 2 (Transport and mixing in the General Circulation)

CoursePlan_BLT&M2_2021

Introduction and Content

This course consists of the two parts.

Part 1 is concerned with the Atmospheric Boundary Layer (ABL) (points 1-5 and 10under learning goals).

Part 2 is concerned with the General Circulation of the Atmosphere.(points 6-10 under learning goals).

Learning goals

1. Is acquainted with the overall characteristics of the atmospheric boundary layers (ABL), i.e. unstable (convective, mixed) ABL and stable (nocturnal) ABL
2. Recognises the various physical mechanisms that define the ABL, i.e. the layer in which the exchange of heat, moisture and momentum with the surface of the Earth occurs at short (sub-daily) time scales
3. Is acquainted with the various statistical terms used in the description of turbulence (variance, covariance, correlation, standard deviation) and the definition of turbulent fluxes (kinematic and dynamic)
4. Is acquainted with physical mechanisms that generate turbulence near the surface of the Earth (wind shear and buoyancy), and can apply that to the everyday meteorological situation
5. Is able to derive and mathematically manipulate simple theoretical models of the katabatic and convective boundary layer.
6. Is able to use the techniques introduced under point (3) to analyse the zonal mean meridional transport of heat, momentum and water vapour due to large scale eddies or planetary waves.
7. Is acquainted with the quasi-geostrophic theory of (a) the vertical propagation of planetary waves into the stratosphere, (b) the interaction of planetary waves with the zonal mean flow in the atmosphere, (c) the mechanism driving the meridional transport of mass in the stratosphere
8. Has an overview of the components of the water cycle (transport of water vapour in the atmosphere, phase transitions, i.e. evaporation, condensation and clouds) and their role in driving the general circulation of the atmosphere
9. Is familiar with the “PV-theta view” of the atmosphere and can use this theoretical framework to understand how radiative flux divergence, latent heat release in the tropical atmosphere and transport and mixing of potential vorticity (substance) interact to produce the jets and the extra-tropical tropopause
10. Is able to interpret reanalyses of observations, using the Python programming language (or MATLAB), and report on the result

Exam

There is no exam in 2021

The grade is derived from the weighted grades for hand-in exercises

Lectures and schedule of spring 2021, part 2

In part 2 a "big picture" is sketched of the complex interacting mechanisms that constitute and bring about the General Circulation.

The hand-in exercises will test your ability to assimilate a lot of theory and information from different fields of study (radiative transfer, turbulence theory, the hydrological cycle and dynamical meteorology)

Lecture 1 : 7 May 2021: BLT&M2-1.pdf

Lecture 2 : 21 May 2021: BLT&M2-2.pdf

Lecture 3 : 28 May 2021: BLT&M2-3.pdf

Lecture 4 : 4 June 2021: BLT&M2-4.pdf

Lecture 5 : 11 June 2021: BLT&M2-5.pdf

Lecture 6 : 25 June 2021: BLT&M2-6.pdf

PV at 350 K in the winter of 2009-2010: animation

PV-anomalies (zonal mean) in the winter of 2008-2009: animation

PV at 350 K in the winter of 2006-2007: animation

Run 3 (no planetary wave drag): animation

Run 4 (with planetary wave drag): animation

Eddy vorticity-flux in January 2007: animation

Eddy vorticity-flux in July 2006: animation

Details of BLT&M part 2

Data needed for problem 12.3 is provided on Blackboard

Data needed for problem 12.5 (a script, which reads these numpy-files) is provided on Blackboard)

u_600K_60N_1979-2015.npy

v_600K_60N_1979-2015.npy

sigma_600K_60N_1979-2015.npy

voabs_600K_60N_1979-2015.npy