Season

Seasons are caused by:
-Earth's 23.5o tilt changing the amount of
sunlight received (from direct to indirect)
-Earth’s revolution around the Sun

If the Earth wasn't tilted what would happen?
Direct Sunlight: concentrated (less spread out) =
more intense energy
Indirect Sunlight: more spread out = less intense
energy

● Earth is tilted away from the Sun
● Winter Solstice: shortest day of the year
● Dec. 21-22
● Less than 12 hrs. of daylight
● Nights get shorter, daytime longer

● Indirect light over N. Hemisphere (shorter days &
less light = cold temps!)
● N. Pole gets 24 hrs. night
● Summer in S. Hemisphere (direct rays at Tropic of
Capricorn)
*Equator gets 12 hours of sunlight

● Earth is tilted towards the Sun
● Summer Solstice: longest day of the year
● June 21-22
● More than 12 hrs. of daylight
● Nights get longer, daytime shorter

● Direct sunlight over N. Hemisphere at Tropic of
Cancer (longer days & more light = warmer temps)
● Arctic Circle gets 24 hrs. of daylight
● Winter in S. Hemisphere

● Earth is not tilted towards or away from the Sun
● Spring (Vernal equinox)
● Mar. 20-21
● All Earth has 12 hrs day/12 hrs. night

● Daytime get longer, nights shorter
● Sun is directly over equator
● Fall/Autumn in S. Hemisphere

● Earth is not tilted towards or away from the sun
● Autumnal equinox
● Sept. 22-23
● All earth has 12 hrs. day/12 hrs. Night

● Daytime gets short, nights longer
● Sun is directly over equator
● Spring in S. Hemisphere