Seasons Science W5-6

• Seasons


  Different periods of the year that are distinguished by special weather and climate conditions
• 4 types of seasons

  • Spring
  • Summer
  • Autumn
  • Winter
• Seasons differs from..

  • Different amount of light received from the sun
  • Different temperatures
  • Different weather conditions that repeat
• Axis

  An imaginary line passing through the center of the earth that goes through both the north pole and the south pole
• Rotation


  The spinning motion of earth around its axis
• Revolution


  The movement of the earth around the sun
• It takes 24 hours or one day for the earth to completely rotate around on its axis
• It takes 365 and 1/4 days or one year for the earth to move around the sun
• Tilt of the earth's axis

  • Tilted at an angle of 23.5 degrees
  • Reason behind the occurrence of seasons
• Earth's axis is tilted


  Different parts of the earth receive different amounts of sunlight as the earth revolves around the sun
• Different amounts of sunlight

  Results in different temperatures and different weather conditions we call seasons
• Solstice


  When the axis of the earth points forward or away from the sun
• Unequal lengths of days and night are experienced in different places of the earth during solstices
• The first day of summer is marked by the summer solstice which occurred during June 21 or June 22
• The first day of winter is marked by the winter solstice which occurred during December 21 or 22
• In June, the north pole is tilted toward the sun

  The northern hemisphere receives more direct rays from the sun and experiences longer daytime than nighttime
• In December, the south pole is tilted toward the sun

  The southern hemisphere receives more direct rays from the sun and experiences summer
• Equinox

  When the axis of the earth does not point either toward or away from the sun
• During an equinox, the duration of days and nights are almost equal
• The first day of spring is marked by the vernal equinox which happens on March 21 or 22
• The first day of the autumn season is marked by the autumnal equinox which happens on September 21 or 22
• Wet and dry seasons

  The two seasons experienced in the Philippines
• The Philippines is located near the equator, so the amount of sunlight it receives does not vary significantly throughout the year
• The rainy season in the Philippines is from June to November, and the dry season is from December to May
• The dry season in the Philippines can be subdivided into cold dry season and hot dry season
• Seasonal change is experienced due to the tilt of the earth's axis, the revolution of the earth around the sun, the direct rays of the sun, and the length of daytime