1. Earth-Sun RelationshipEarth-Sun Relationship
 (Use with Notes and Homework Quiz(Use with Notes and Homework Quiz
handout)handout)

2. Weather vs ClimateWeather vs Climate
What is the weather like today?What is the weather like today?
Is it like this EVERY day? Why?
What is the difference between
WEATHER and CLIMATE?

3. Weather and ClimateWeather and Climate
 WeatherWeather – The– The temporarytemporary environmentalenvironmental
conditions in a localized area over a shortconditions in a localized area over a short
period of time.period of time.
*In other words…what it’s like OUTSIDE,
right HERE, right NOW
 ClimateClimate –– The long-termThe long-term environmentalenvironmental
conditions across a large area and long time.conditions across a large area and long time.
*In other words…the AVERAGE of all the
WEATHERS

4. What affects weather and climate?What affects weather and climate?
 ThereThere are two major factors that affect theare two major factors that affect the
overall environment andoverall environment and climateclimate……
-The tilt of the Earth in relation to it’s orbit
around the Sun
- The direction of that tilt that changes as
the Earth travels around the Sun

5. First, some basic vocabulary…First, some basic vocabulary…
 RevolutionRevolution –– one ORBITone ORBIT, or trip around the, or trip around the
Sun. This takes the EarthSun. This takes the Earth 365 ¼ days365 ¼ days
Rotation – one
SPIN of the
Earth on it’s
axis. This
takes about 24
hours…one
DAY.

6. EarthEarth’s’s TILTTILT
 The Earth is not vertical (straight up-and-The Earth is not vertical (straight up-and-
down) in relation to itdown) in relation to it’s orbital path, it’s’s orbital path, it’s tiltedtilted
23 ½ degrees from vertical23 ½ degrees from vertical..
This tilt means that
the Sun’s energy
doesn’t hit the
Earth equally.

7. EarthEarth’s’s TILTTILT
 ThisThis tilt results in uneven heating of thetilt results in uneven heating of the
EarthEarth’s surface’s surface..
“Direct”
sunlight
“Indirect”
sunlight

8. Section 1Section 1
The relationship between the Earth and the
sun affects climate, which influences life on
Earth in dramatic ways.
Climate and Weather
• Earth’s tilt is one reason for variations in sunlight.
• The angle of tilt affects the temperature, which is
measured in Fahrenheit or Celsius.
• Earth rotates on its axis, making one complete
rotation from west to east every 24 hours.

9. FromFrom TILTTILT to SEASONSto SEASONS
 As the Earth travels around the Sun, theAs the Earth travels around the Sun, the tilttilt
changes in relation to the Sun. Sometimeschanges in relation to the Sun. Sometimes
“toward” the Sun, sometimes “away”, and“toward” the Sun, sometimes “away”, and
sometimes neither.sometimes neither.
This creates aThis creates a
predictablepredictable
cycle ofcycle of
warmer andwarmer and
cooler periods,cooler periods,
or seasons.or seasons.

12. Section 1Section 1
• While Earth is rotating on its axis, it is also
traveling in an orbit around the sun—this
revolution takes 365 days to complete.
• The Earth’s revolution and tilt cause changes in
the angle and amount of sunlight that reach
different locations on the planet, also known as
seasons.
Climate and Weather (cont.)
Effects of Earth’s Tilt

13. SeasonsSeasons
 Because the direction of the tilt (Because the direction of the tilt (“towards” or“towards” or
“away”) is opposite for the Northern and“away”) is opposite for the Northern and
Southern hemispheres, so are the seasons.Southern hemispheres, so are the seasons.
Here is the rule to remember…
Tilted “toward” the Sun means Summer,
tilted “away” from the Sun means winter

14. Solstice and EquinoxSolstice and Equinox
 SolSolsticestice – the point at which the Earth is pointed farthest– the point at which the Earth is pointed farthest
toward / away from the Sun, creatingtoward / away from the Sun, creating long summer days andlong summer days and
short winter daysshort winter days . (Latin root word. (Latin root word “sol”)“sol”)
– Summer – around June 21Summer – around June 21
– Winter – around December 21Winter – around December 21 EquinoxEquinox – the– the
point at which thepoint at which the
Earth is notEarth is not
pointed toward ORpointed toward OR
away from theaway from the
Sun, creatingSun, creating
equalequal day andday and
nightnight.. ((“equi-nox”)“equi-nox”)
-Spring (“Vernal”)
around March 21
- Fall (“autumnal”)
around Sept. 21

15. Section 1Section 1Climate and Weather (cont.)
• The Tropics of Cancer and Capricorn
– When the sun’s rays directly strike the Tropic
of Cancer, this marks the beginning of summer
in the Northern Hemisphere.
– When the sun’s rays directly strike the Tropic
of Capricorn, this marks the beginning of
winter in the Northern Hemisphere.

16. Section 1Section 1Climate and Weather (cont.)
• The Poles
– At the North Pole, the sun never sets from
about March 20 to September 23.
– At the South Pole, the sun never sets from
about September 23 to March 20.
The Earth’s Seasons

17. What are the Tropics?What are the Tropics?
 When we think of the tropics, we thing ofWhen we think of the tropics, we thing of
warm, humid weather and great beaches!warm, humid weather and great beaches!
 Although this is true, the term comes fromAlthough this is true, the term comes from
the area of the earth that lies between thethe area of the earth that lies between the
two lines of latitude that are called thetwo lines of latitude that are called the
Tropic of Cancer and the Tropic ofTropic of Cancer and the Tropic of
Capricorn. These areas tend to be warm,Capricorn. These areas tend to be warm,
humid, green and beautiful.humid, green and beautiful.

18.  The Tropic of Cancer is found at 23 ½The Tropic of Cancer is found at 23 ½
degrees North Latitudedegrees North Latitude
 The Tropic of Capricorn is found at 23 ½The Tropic of Capricorn is found at 23 ½
degrees South Latitudedegrees South Latitude

19. Section 1-GTRSection 1-GTR
A. Tropic of Cancer
Earth-Sun Relationships
B. Tropic of Capricorn

20. Section 1Section 1
The Earth rotates on its
axis, making one
complete rotation every
A. Month
B. 24 hours
C. 365 days
Earth-Sun Relationships

21. EarthEarth’s’s tilttilt affects length of daysaffects length of days
 Places experiencing summerPlaces experiencing summer
havehave “longer” days“longer” days
(more sunlight per 24 hrs.)(more sunlight per 24 hrs.)
 Places experiencing winterPlaces experiencing winter
havehave “shorter” days“shorter” days
(less sunlight per 24 hrs.)(less sunlight per 24 hrs.)
 Areas above 66 ½ degreesAreas above 66 ½ degrees
N or S will experience 24 hr.N or S will experience 24 hr.
extremes (light and dark)extremes (light and dark)
depending on the seasondepending on the season
 (Land of the Midnight Sun)(Land of the Midnight Sun)
24
hrs.
of
dark
from
May
to
August
24
hrs.
of
light
from
Nov.
to
Feb.
Longer
Summer
days
Shorter
Winter
days

23. Section 1Section 1
The imaginary line running from
the North Pole to the South Pole
through the planet’s center is
known as which term?
A. Equator
B. Solstice
C. Axis
D. Equinox

24. Section 1Section 1
The natural process of the greenhouse
effect has been influenced by human
activity.
The Greenhouse Effect
• Like the glass in a greenhouse, the atmosphere traps
some heat and keeps it from escaping back into
space too quickly so that the Earth is warm enough to
maintain life.

25. Section 1Section 1The Greenhouse Effect (cont.)
• Many scientists claim that in recent decades a
rise in atmospheric carbon dioxide levels has
coincided with a general rise in global
temperatures, also known as global warming.
The Greenhouse Effect

26. Greenhouse EffectGreenhouse Effect
 Normally, when the Sun’s energy
penetrates the atmosphere, some of
it is absorbed, and some of it is
reflected back to space.
 Human and natural events increase
pollutants that trap the reflected
energy and send it back to the Earth
again, increasing the Earth’s heat.

27. Section 1Section 1
Which of the following do you think has
caused global warming?
A. A natural cycle
B. Human activity
C. Both
D. Neither