2.2 The global energy budget

• Insolation


  incoming solar radiation
• Planetary albedo


  Reflection from the earth's surface including atmosphere and clouds
• Greenhouse effect


  process by which certain gasses allow short-wave radiation from the sun to pass.
• Intertropical convergence zone(ITCZ) or equatorial through


  low pressure area where N-E trade winds and S-E trade winds converge
• Low-latitude winds

  trade winds between 30 degrees N and S
• Maritime or oceanic

  describes areas close to the sea/ coast and where temperatures are lower than in inland areas in summer, but higher than in inland areas in winter.
• Continental


  areas distant from the sea
• Prevailing wind


  the direction from which the wind most commonly blows in a locality
• Gyre

  dominant large-scale pattern of rotating currents in an ocean
• Pressure gradient


  difference in air pressure between 2 areas - steep gradient produces strong winds - low gradient produces weak winds
• pressure (air)


  at any point on the Earth's surface is due to the weight of the air above it; it decreases as altitude increases. At sea level the average pressure is 1013 millibars (mb). Areas of relatively high pressure are called anticyclones; areas of low pressure are called depressions.
• Coriolis effect


  an effect that causes any body that moves freely with respect to the rotating earth to veer to the right in the northern hemisphere and to the left in the southern
• Geotropic balance


  when there is a balance between the Coriolis effect and the pressure gradient force
• Geotropic wind


  the wind that occurs when there is an exact balance between the Coriolis effect and the pressure gradient force
• Centrifugal force


  an outward force at right-angles to the wind
• Friction

  force resisting the motion of 2 objects against eachother
• General circulation model


  of atmosphere is based on convection. In the simplest case, cells of warm air rise at the equator and descend at the poles
• Stability


  describes stable, high-pressure conditions producing calm, dry weather
• El Nino

  an anomalous warming of surface waters in the eastern equatorial Pacific Ocean. It is linked to climatic disturbances throughout the world
• deficit

  shortage or negative balance
• why does the atmosphere not get any hotter after constantly getting more radiation (1) and how is it achieved (3)

  there is a balance in inputs and outputs. achieved radiation, convection (heat transfer by movement of a gas or liquid), conduction (heat by contact)
• what happens to insolation? (4)

  1/5 absorbed by ozone, some reflected by atmosphere, 1/4 reflected by clouds or rain, some albedo'd, 2/5 reflected to space.
• what is the pattern of temp from the tropic of capricorn

  decline northwards
• what are the variations of temp at the equator

  little seasonal varitations
• what are the two main influences on atmospheric transfer

  pressure variations and ocean currents.
• does air flow from high or low pressure to what


  from high to low
• what does low pressure indicate about the weather?

  bad weather
• what is the seasonal contrast in the northern and southern hemisphere

  northern - greater contrasts, southern - much simpler average conditions
• explain the convergence zone (3)

  few km wide, winds blow inwards therefore forming low pressure zones.
• what directions do winds flow between 10 degrees and 30

  they are easterlies, they fly west
• what is the weather in the 10-30 degree zone

  fairly predictable: warm, dry mornings and showery afternoons, caused by evaporation from tropical seas.
• what are westerly winds

  winds that fly east - from 35 to 60 degrees
• what is the most important factor in determining temp on a global scale and 2 other factors

  latitude. angle of sun and thickness of atmosphere
• what is the land-sea distribution in northern hemisphere

  50-50
• what is land-sea distribution in the southern hemisphere

  90 ocean 10 land
• why does water heat slower then land (2)

  its clear - sun rays penetrate deeper, tides carry the heat futther
• what is the pattern of ocean currents in northern and southern hemisphere (anti/clockwise)

  northern - clockwise and southern - anticlockwise
• from where to where is the oceanic convection movement?


  from polar regions (where salty water sinks) to the equator
• where does high pressure dominate (degrees)

  from 25-30 latitude
• describe the general circulation model (where warm air is transferred - latitude and pressure, what weather pressure produces) (3)

  warm air is transferred polewards, air rises = low pressure, low pressure creates rain and high dry conditions