LESSON5: SOLSTICES AND EQUINOXES

Season

• A quarter of the year with unique weather pattern characteristics.

• Determined by the amount of sunlight being received.

• Earth’s axial tilt causes seasons.

Solstices

• Axis of the Earth points forward or away from the Sun.

• Unequal length of day and night.

The Solstices: 

1. June Solstices (Summer Solstice)

• Summer: higher insolation, longer day time. 

• Winter: lower insolation, longer night time. 

• North: Summer 

• South: Winter

2. December Solstices (Winter Solstice)

• Summer: lower insolation, longer night time.

• Winter: higher insolation, longer day time. 

• North: Winter

• South: Summer
  

Equinox

• Axis of the Earth DOES NOT point forward or away from the Sun.

• Almost equal length of day and night.

The Equinoxes: 

1. March Equinox (Spring Equinox)

• North: Spring

• South Autumn 

2. September Equinox (Fall Equinox) 

• North: Autumn

• South: Spring
  

Solstice-Equinox Cycle: 

1. Summer Solstice 

• Jun 21: Northern H.

• Dec 21: Southern S.

• Summer is marked by longer days and shorter nights.

• It is the hottest time of the year with the shortest shadows. 

2. Fall Equinox 

• Sept 21- Northern H.

• Mar 21- Southern H.

• The leaves of non-evergreen plants turn red and orange and eventually ‘fall’ as plants prepare for the winter. 

• Some animals eat a lot of food and store food for winter.

3. Winter Solstice

• Dec. 21- Northern H.

• June 21- Southern H.

• This is when animals hibernate. 

• Winter is marked by longer nights and shorter days.  

• It is the coldest time of the year with the longest shadows. 

4. Spring Equinox 

• March 21- Northern H.

• Sept.  21- Southern H.

• Some animals come out of hibernation.

• Plants start to ‘spring’ back to life, aided by the mild temperature.

Seasons in the Philippines

• TWO seasons (Wet and Dry seasons)

• The amount of sunlight does not vary significantly throughout the year.

• Only the equal length of day and night are observed.