Atmospheric Circulation Course

Lesson 1 • Composition and Structure of the Atmosphere

Covers atmospheric gas composition, aerosols, and vertical layering by temperature. Provides the physical context for understanding how energy and mass move through the atmosphere.

Lesson 2 • Solar Radiation and Energy Budget

Examines incoming solar radiation, albedo, and Earth's outgoing longwave radiation. Establishes the energy imbalance that drives global atmospheric circulation.

Lesson 3 • Atmospheric Thermodynamics Basics

Introduces temperature, pressure, and density relationships governing air behaviour. These thermodynamic principles underpin all circulation-driving mechanisms covered later.

Lesson 1 • The Coriolis Effect

Explains Earth's rotation-induced deflection of moving air and its latitude dependence. Essential for understanding why large-scale winds curve rather than flow straight.

Lesson 2 • Friction and Turbulent Boundary Layer

Describes surface friction effects on wind speed and direction in the planetary boundary layer. Shows how friction modifies geostrophic balance near the surface.

Lesson 3 • Pressure Gradient and Gravity Forces

Defines the pressure gradient force as the primary driver of horizontal air motion. Connects pressure maps to wind initiation and direction.

Lesson 4 • Balanced Flow Regimes

Derives geostrophic, gradient, and cyclostrophic wind balances from force equations. Students apply these balances to interpret synoptic-scale wind patterns.

Lesson 1 • Polar Cell and High-Latitude Circulation

Covers the thermally direct polar cell, polar vortex, and surface polar easterlies. Connects polar dynamics to mid-latitude weather through stratosphere-troposphere coupling.

Lesson 2 • Ferrel Cell and Mid-Latitude Westerlies

Explains the thermally indirect Ferrel cell maintained by eddy momentum fluxes. Links mid-latitude westerlies to baroclinic wave activity and storm tracks.

Lesson 3 • Monsoon Systems and Seasonal Shifts

Analyses land-sea thermal contrast as the driver of monsoonal reversals in wind direction. Seasonal shifts in the ITCZ and pressure systems are quantified.

Lesson 4 • Zonal Mean Atmospheric Energy Transport

Quantifies poleward transport of sensible heat, latent heat, and momentum by mean flow and eddies. Demonstrates how the atmosphere compensates for the equator-to-pole energy imbalance.

Lesson 1 • Mid-Latitude Cyclone Life Cycle

Traces cyclone development from wave disturbance through occlusion using the Norwegian model. Connects surface pressure evolution to upper-level trough-ridge patterns.

Lesson 2 • Upper-Level Troughs and Ridges

Analyses 500 hPa geopotential height patterns and their relationship to surface weather. Rossby wave propagation explains the planetary-scale trough-ridge configuration.

Lesson 3 • Synoptic-Scale Precipitation Patterns

Links large-scale vertical motion to precipitation distribution around cyclones and fronts. Omega equation diagnostics connect dynamic forcing to observed rainfall.

Lesson 4 • Frontal Systems and Air Masses

Classifies air masses by source region and defines frontal boundaries between contrasting air masses. Frontal analysis skills are applied to weather map interpretation.

Lesson 1 • Mesoscale Convective Systems

Examines organised convective clusters, squall lines, and mesoscale convective complexes. Their role in tropical rainfall and circulation feedback is quantified.

Lesson 2 • Tropical Thermodynamics and Convection

Covers convective available potential energy, convective inhibition, and tropical instability. Establishes the thermodynamic environment that sustains deep tropical convection.

Lesson 3 • Walker Circulation and ENSO

Defines the zonal overturning Walker circulation and its disruption during El Nino and La Nina. ENSO teleconnections to global precipitation and temperature anomalies are mapped.

Lesson 4 • Tropical Cyclone Structure and Dynamics

Describes the warm-core structure, wind field, and energy source of tropical cyclones. Intensity and track dynamics are linked to sea surface temperature and environmental shear.

Lesson 1 • Planetary Wave Propagation into the Stratosphere

Applies Eliassen-Palm flux theory to diagnose upward wave activity from the troposphere. Wave breaking and absorption in the stratosphere are linked to mean flow deceleration.

Lesson 2 • Sudden Stratospheric Warming Events

Analyses the dynamics of major and minor sudden stratospheric warmings and polar vortex disruption. Downward coupling to the troposphere and surface impacts are examined.

Lesson 3 • Stratospheric Mean Circulation

Describes the Brewer-Dobson circulation, stratospheric jets, and the quasi-biennial oscillation. Establishes the stratospheric background state that modulates wave propagation.

Lesson 1 • Southern Annular Mode

Describes the dominant mode of Southern Hemisphere extratropical variability and its jet stream shifts. SAM trends are connected to ozone depletion and greenhouse gas forcing.

Lesson 2 • Teleconnection Patterns and Rossby Wave Trains

Explains how tropical heating anomalies excite Rossby wave trains that alter remote circulation. Pattern correlation and empirical orthogonal function methods identify key teleconnections.

Lesson 3 • North Atlantic Oscillation and Arctic Oscillation

Defines the NAO and AO indices and their associated pressure and wind anomaly patterns. Links these modes to European and North American winter climate variability.

Lesson 4 • Pacific Decadal Oscillation and AMO

Characterises decadal sea surface temperature patterns in the Pacific and Atlantic and their atmospheric responses. Decadal variability modulates ENSO impacts and regional climate trends.

Lesson 1 • Circulation Feedbacks and Tipping Points

Identifies circulation-related climate feedbacks including water vapour, lapse rate, and cloud feedbacks. Potential tipping points in the Atlantic overturning and monsoon systems are assessed.

Lesson 2 • Arctic Amplification and Mid-Latitude Impacts

Explains the disproportionate warming of the Arctic and its proposed effects on mid-latitude circulation. Debates over jet stream waviness and extreme weather linkages are critically reviewed.

Lesson 3 • Observed Circulation Trends

Documents observed poleward shifts of jet streams, Hadley cell expansion, and storm track changes. Reanalysis datasets and attribution methods are used to separate forced trends from variability.

Lesson 4 • Stratospheric Ozone Recovery and Circulation

Evaluates how ozone recovery interacts with greenhouse gas forcing to alter stratospheric and surface circulation. Competing effects on the SAM and Southern Hemisphere westerlies are analysed.