Atmospheric systems

• What is the first layer of the atmosphere moving outwards from the Earth's surface?

  Troposphere
• What happens to temperature in the troposphere as altitude increases?

  Temperature decreases with altitude
• Why does temperature decrease in the troposphere?

  Because the Earth's surface warms the air
• What is the environmental lapse rate?

  Temperature decrease by 1000 m increase
• What is the main characteristic of the tropopause?

  It is an isothermal layer
• What is the second layer of the atmosphere?

  Stratosphere
• How does temperature change in the stratosphere?

  Temperature steadily increases with height
• What causes the temperature inversion in the stratosphere?

  Concentration of ozone absorbs UV radiation
• What is the third layer of the atmosphere?

  Mesosphere
• What happens to temperature in the mesosphere?

  Temperature falls rapidly with height
• What is the fourth layer of the atmosphere?

  Thermosphere
• What causes the rapid temperature rise in the thermosphere?

  Increasing proportion of atomic oxygen
• What is the atmosphere like at the height of the thermosphere?

  Virtually a vacuum
• What is the role of solar radiation in the Earth's energy balance?

  It is the prime source of energy
• What happens to solar radiation when it enters the Earth's atmosphere?

  It is absorbed, reflected, and scattered
• What is albedo?

  The ratio of reflected radiation to incoming radiation
• What factors affect albedo?

  Color, depth, and texture of the surface
• What is the average albedo of clouds?

  30-40%
• How does the color of a surface affect its albedo?

  Lighter colors have higher albedo
• What is the natural greenhouse effect?

  It traps outgoing radiation to warm the Earth
• What percentage of outgoing radiation is lost to space?

  6%
• What is the heat budget?

  The balance between incoming and outgoing radiation
• What is a positive heat balance?

  More incoming radiation than outgoing
• Where does a negative heat balance occur?

  At high latitudes and altitudes
• What are the two major transfers of heat in the atmosphere?

  Vertical and horizontal heat transfers
• What is latent heat?

  Energy needed to change a substance's state
• How do ocean currents affect temperature?

  They carry warm water polewards and cool water equatorwards
• What is the North Atlantic Drift?

  A warm ocean current warming Europe
• What is continentality?

  Difference in heat absorption between land and sea
• How does altitude affect temperature?

  Temperature falls with height above sea level
• What is the average rate of temperature decrease with altitude?

  0.6-1°C per 100 m
• What is the effect of aspect on temperature?

  South-facing slopes receive more sun
• What causes seasonal variations in insolation?

  Earth's rotation and tilt as it revolves
• When do equinoxes occur?

  21st March and 22nd September
• What happens during solstices?

  The sun is overhead at the tropics
• What is the general circulation of the atmosphere responsible for?

  Global energy transfer
• What is normal atmospheric pressure at sea level?

  1013 mb
• What do isobars represent?

  Lines of equal atmospheric pressure
• What does a steep pressure gradient indicate?

  Strong winds
• What does a gentle pressure gradient indicate?

  Light winds