MT24A: Atmosphere and Ocean Dynamics

Module Provider:

Meteorology

Number of credits:

20 [10 ECTS credits]

Level:

I (Intermediate)

Terms in which taught:

Autumn and Spring

Module Convenor:

Pre-requisites:

MT11A MT11B

Co-requisites:

Modules excluded:

Module version for:

2007/8

Aims:
This module aims to introduce the physical processes affecting fluid motion on various scales in the atmosphere and ocean, building up to the equations used in studying atmospheric and oceanic motions, and to solve related fluid flow problems. The concepts will be illustrated by reference to atmospheric and oceanic phenomena and through laboratory demonstrations.

Assessable learning outcomes:
By the end of this module, the student should be able to:
Describe the physical processes affecting a fluid, including the basic effects of rotation and stratification
Solve basic dynamical problems for a fluid
Estimate relevant non-dimensional parameters
Describe and make quantitative use of the equations of motion for the atmosphere and ocean
Describe and interpret physically basic atmospheric and oceanic flows, and solve quantitative problems relating to these flows.

Additional outcomes:
Students will enhance their problem solving skills.

Outline content:
The nature of fluids, pressure, pressure gradient force, streamlines and Bernoulli's theorem, circulation and vorticity, vortex tubes, irrotational flows, grad, div and curl, divergence theorem and Stokes' theorem, Eulerian and Lagrangian rates of change, viscosity, Reynolds number, inertial and rotating frames of reference, Coriolis and centrifugal forces, inertial oscillations, Rossby number, Taylor-Proudman theorem, buoyancy and stratification, buoyancy oscillations, Richardson number, thermal wind, Burger number, Rossby deformation radius, rotating annulus, Blasius boundary layer, Ekman layer.

Navier-Stokes equations, scaling analysis, primitive equations, vorticity equation and mechanisms for changing vorticity, potential vorticity, barotropic vorticity equation, barotropic flow over orography, beta effect, Sverdrup balance and wind-driven gyres, Stommel-Arons model of the abyssal ocean circulation, surface waves and sound waves, phase and group velocity, wave dispersion, wave breaking, linearization of the equations of motion, dispersion relations, reduced-gravity model, internal gravity waves, Rossby waves, Kelvin waves, introduction turbulence, chaos and eddy fluxes.

Brief description of teaching and learning methods:
One 3 hour session per week. This will typically involve a 1 hour lecture followed by a short laboratory demonstration (to small groups) and a problem solving class. Basic concepts introduced during the lectures will be further developed during the problem solving class.

Contact hours:

Assessment:
Coursework
Two assessed problem sheets, one due at the end of each term (15% each) plus an open-book test at the end of the Autumn term (20%)
Relative percentage of coursework: 50%
Examinations
A 2 hour examination requiring answers to 2 out of 3 questions
Requirements for a pass
40% overall
Reassessment arrangements
September examination only