Chapter 3 : Lesson 1 Earth-Sun Relationships

Essential Question: How do the relationships between the Earth and the sun affect climate?

Climate vs. Weather Weather: condition of the atmosphere in one place during a limited time

Climate vs. weather Climate: weather patterns of an area over a long period of time

The most important factor of climate is Earth’s position in relation to the sun

Axis: imaginary line runs from pole to pole, through center Earth’s Tilt Axis: imaginary line runs from pole to pole, through center Tilted at 23 ½ º angle Places receive diff. amounts of light at diff. times

Areas with direct sunlight warmer temps. (Tropics, Equator) Earth’s Tilt Areas with direct sunlight warmer temps. (Tropics, Equator) Areas with indirect sunlight cooler temps. (High latitudes/ mid-lat)

Earth rotates on its axis Earth’s Rotation Earth rotates on its axis One complete rotation = 24 hours From west to east, one hemisphere at a time

As it rotates, Earth revolves around the sun (365 days) Earth’s Revolution As it rotates, Earth revolves around the sun (365 days) Tilt + Revolution = seasons As in length of days and temp. Reversed for N & S hemispheres

Equinox: Spring and Fall Solstice: Summer and Winter Equinoxes & Solstices Equinox: Spring and Fall Equal days and nights Solstice: Summer and Winter Longer day or shorter day

Spring equinox March 21- rays hit Equator directly…equal day/night Equinoxes & Solstices Spring equinox March 21- rays hit Equator directly…equal day/night Summer solstice June 22- rays hit Tropic of Cancer…longest day (US)

Fall equinox Sept. 23- rays hit Equator directly…equal day/night Equinoxes & Solstices Fall equinox Sept. 23- rays hit Equator directly…equal day/night Winter solstice December 22- rays hit Tropic of Capricorn…shortest day (US)

So if it is summer in Houston, what season is it in South Africa? Equinoxes & Solstices So if it is summer in Houston, what season is it in South Africa? If we are wearing long sleeves and jackets, what are they wearing in China?

“lands of the midnight sun” The Poles For 6 months one pole is pointed toward sun  constant sunlight Other is pointed away little to no sunlight “lands of the midnight sun”

Midnight Sun: Continuous daylight, a time when the sun is visible at midnight during the summer in either the Artic or Antarctic Circle

The perfect balance must be kept: The Greenhouse Effect The perfect balance must be kept: Too much heat escapes freeze Too much heat is trapped dry out

Review Question: Chapter 3 : Lesson 1 Read pages 60-63 and answer Review Questions on page 63 Hand in Google Class Room.