The Air Ocean

DOMAIN 01

Atmosphere as System

• Envelope held by Gravity
• Coupled with Ocean/Land
• Fluid Dynamics System
• Protective Shield

DOMAIN 02

Composition

• Nitrogen (78%) & Oxygen (21%)
• Argon & Trace Gases
• Variable Gases (H2O, CO2)
• Homosphere vs Heterosphere

DOMAIN 03

Atmospheric Water

• Water Vapour (0-4%)
• Humidity Concepts
• Source of Precipitation
• Potent Greenhouse Gas

DOMAIN 04

Atmospheric Particles

• Aerosols, Dust, Smoke
• Sea Salt & Volcanic Ash
• Condensation Nuclei
• Radiation Scattering

DOMAIN 05

Vertical Structure

THERMO

MESO

STRATO

TROPO

• Layering by Temp Profile
• Tropo, Strato, Meso, Thermo
• The 'Pauses' (Boundaries)
• Pressure Decrease with Height

DOMAIN 06

Troposphere

• Lowest Layer (Weather Sphere)
• Temp Decreases with Height
• Contains almost all Water Vapour
• Convection & Turbulence

DOMAIN 07

Stratosphere

✈

• Temp Increases with Height
• Stable Stratification
• Contains Ozone Layer
• Commercial Flight Cruising

DOMAIN 08

Ozone Layer

• O3 Gas Concentration
• UV Radiation Absorption
• Ozone Depletion (CFCs)
• The Ozone 'Hole'

DOMAIN 09

Mesosphere

• Temp Declines (Coldest Layer)
• Meteor Ablation (Burning up)
• Low Density
• Mesopause Boundary

DOMAIN 10

Thermosphere

• Temp Increases dramatically
• Solar X-ray/UV Absorption
• Ionosphere (Radio waves)
• Auroras occur here

DOMAIN 11

Exosphere

• Outermost Layer
• Extremely Low Density
• H and He Gases
• Atmospheric Escape to Space

DOMAIN 12

Atmospheric Pressure

SEA LVL

MOUNTAIN

• Weight of Air column
• Decreases with Altitude
• Measured in Millibars (hPa)
• High vs Low Pressure Areas

DOMAIN 13

Pressure Gradient

H

L

• Difference in Pressure
• Force driving air High to Low
• Determines Wind Speed
• Initial cause of wind

DOMAIN 14

Isobars

H

• Lines of Equal Pressure
• Close spacing = strong wind
• Wide spacing = gentle wind
• Synoptic Map interpretation

DOMAIN 15

Insolation

• INcoming SOLar radiATION
• Solar Constant
• Angle of Incidence effects
• Day Length & Season

DOMAIN 16

Solar Radiation

• Shortwave Electromagnetic
• UV, Visible, near-IR
• High Energy Transmission
• Passes through atmosphere

DOMAIN 17

Albedo

• Surface Reflectivity %
• Snow/Ice = High Albedo
• Ocean/Forest = Low Albedo
• Albedo Feedback loop

DOMAIN 18

Terrestrial Radiation

• Earth's Outgoing Energy
• Longwave Infrared
• Lower Energy than Solar
• Absorbed by Greenhouse Gases

DOMAIN 19

Greenhouse Effect

• Shortwave enters easily
• Longwave is trapped/re-emitted
• Water Vapour, CO2, Methane
• Natural warming mechanism

DOMAIN 20

Earth's Heat Budget

INCOMING 100% = OUTGOING 100%

GLOBAL ENERGY BALANCE

• Balance of In vs Out radiation
• Reflection vs Absorption
• Latent & Sensible Heat
• Global equilibrium

DOMAIN 21

Heat Transfer

• Conduction (Contact)
• Convection (Vertical fluid)
• Advection (Horizontal wind)
• Radiation (Waves)

DOMAIN 22

Conduction

• Molecular heat transfer
• Ground heating adjacent air
• Inefficient for whole atmosphere
• Boundary layer importance

DOMAIN 23

Convection

• Vertical air motion
• Warm air rises (Buoyancy)
• Cool air sinks
• Drives deep cloud formation

DOMAIN 24

Advection

• Horizontal transport
• Wind moving heat/moisture
• Warm or Cold Air Advection
• Frontal weather changes

DOMAIN 25

Temperature

• Measure of kinetic energy
• Diurnal (Daily) Range
• Annual Range
• Thermal Regimes

DOMAIN 26

Controls of Temp

LatitudeInsolation

AltitudeLapse Rate

DistanceFrom Sea

CurrentsOcean Heat

• Latitude (Primary control)
• Altitude (Cooling)
• Continentality vs Marine effect
• Cloud cover & Albedo

DOMAIN 27

Horizontal Temp

• Equator-to-Pole Gradient
• Isotherms (Lines of equal temp)
• Land-Sea thermal contrast
• Seasonal shifting

DOMAIN 28

Vertical Temp Structure

ALT TEMP

• Environmental Lapse Rate (ELR)
• Adiabatic Cooling/Warming
• Dry vs Moist Adiabatic Rates
• Atmospheric Stability

DOMAIN 29

Temperature Inversion

• Temp INCREASES with height
• Reversal of normal profile
• Highly stable air (traps pollution)
• Radiation, Valley, Subsidence types

DOMAIN 30

Atmospheric Stability

• Stable (Air resists lifting)
• Unstable (Air continues rising)
• Comparison of ELR to DALR/MALR
• Convection potential

DOMAIN 31

Pressure Belts

POLAR HIGH

SUBPOLAR LOW

SUBTROPICAL HIGH

EQUATORIAL LOW

• Thermal vs Dynamic origin
• Equatorial Low (ITCZ)
• Subtropical Highs (Deserts)
• Seasonal migration

DOMAIN 32

Hadley Circulation

• Tropical heating driven
• Rising air at Equator
• Sinking air at 30° lat
• Creates Trade Winds

DOMAIN 33 & 34

Ferrel & Polar Cells

• Ferrel Cell (Dynamic, mid-lat)
• Drives the Westerlies
• Polar Cell (Thermal, high-lat)
• Drives Polar Easterlies

DOMAIN 35

Planetary Winds

<< POLAR E WESTERLIES >> << TRADES

• Persistent global belts
• Trades (Tropics)
• Westerlies (Mid-latitudes)
• Polar Easterlies

DOMAIN 36

Coriolis Effect

• Due to Earth's rotation
• Deflects Right in NH
• Deflects Left in SH
• Zero at equator, max at poles

DOMAIN 37

Surface Friction

• Slows wind near ground
• Reduces Coriolis force
• Causes winds to cross isobars
• Boundary layer effect

DOMAIN 38

Local Winds

<<<

• Sea & Land Breezes
• Mountain & Valley Breezes
• Katabatic (Cold drainage)
• Foehn/Chinook (Warm, dry)

DOMAIN 39

Jet Streams

• High-altitude fast winds
• Geostrophic balance
• Subtropical & Polar Front Jets
• Meander in Rossby Waves

DOMAIN 40

Polar Front

• Boundary: Warm Tropics & Cold Polar air
• Steep Temp/Pressure gradient
• Cyclogenesis zone
• Mid-latitude weather systems

DOMAIN 44

Atmospheric Dynamics

• Balance of Forces
• PGF vs Coriolis (Geostrophic)
• Friction alters balance
• Determines actual wind vector

DOMAIN 45

Vertical Air Motion

• Rising Air (Expansion/Cooling/Clouds)
• Sinking Air (Compression/Warming/Clear)
• Convergence vs Divergence
• Crucial for precipitation

DOMAIN 48

The Great Air Engine

• Insolation → Heat Differences
• Pressure Gradient → Wind
• Coriolis + Friction
• Circulation Redistributes Heat