APES 4.7 Solar Radiation and Earth's Seasons

• Insolation is the incoming solar radiation
  • (insolation = solar radiation/area)
  • The more area, the less solar radiation is being delivered to a single point
• The surface most perpendicular to the sun will have the highest concentration of solar radiation per area
• The angle of incidence decreases moving towards the poles, increasing area of incidence, lowering insolation

Seasons

• These only apply to the northern hemisphere
• December 21/22 marks the winter solstice
  • The shortest day and longest night
  • Moving on from here, days will get longer
• March 20/21 is the vernal equinox
  • Day and night is equal
  • Days are still getting longer
• June 21/22, the summer solstice
  • The longest day and shortest night
  • Nights get longer after this point
• September 22/23 is the autumnal equinox
  • Day and night is equal
  • Nights are getting longer
• In the southern hemisphere, equinox days are the same, but the summer and winter solstices are switched