Earth’s Tilt

and

Seasons

Axis:

imaginary line that passes through Earth’s center and the North & South Poles

Earth’s axis tilt = 23.5°

• causes Earth’s seasons• causes ‘length’ of day to change

throughout the year

23.5°

23.5°

Plane of orbit

Rotation:

Earth’s spinning on its axis

• causes night & day

• Earth rotates every 24 hours

Revolution: movement of one object around

another

• Earth revolves around the sun every 365.25 days

Orbit:

an object’s path as it revolves around another object

• Earth’s orbit around the sun is slightly elliptical, not perfectly circular

• When we are tilted toward the sun, we have summer.

• When we are tilted away from the sun, we have winter

23.5°

23.5°

Plane of orbit

Equator: imaginary line encircling the Earth like a belt at 0° latitude

• All lines of latitude are measured as north or south of the equator.

Tropic of Cancer: latitude 23.5° N

Tropic of Capricorn: latitude 23.5°S

Arctic Circle: latitude 66.5° N

Antarctic Circle: latitude 66.5°S

Solstice: 2 days of the year when the noon sun is directly overhead at either 23.5° S or 23.5° N

1.Summer: longest “day” of year (daylight)

Around June 21st

2.Winter: shortest “day” of year (daylight)

Around Dec. 21st

Equinox: 2 days of the year when the noon sun is directly overhead at the equator (equal amt. of day & night)

1. Vernal (spring) Around March 21st

2. Autumnal (fall)

Around Sept. 21st

Seasons simulator

Copy this diagram into your notes.

What season is it at your house in this animation?

Climate

Global Wind Patterns

&

“Climate is what you expect, weather is what you get.”

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3 BASIC CLIMATE ZONES

A. Tropical zone = HOT

Tropic of Cancer (23.5°N)

Tropic of Capricorn (23.5°S)

Tropic of Cancer (23.5°N)

Tropic of Capricorn (23.5°S)

Arctic Circle (66.5°N)

Antarctic Circle (66.5°S)

C. Polar zones (2) = COLD

Arctic circle (66.5°N)

Antarctic circle (66.5°S)

Mt. Kilimanjaro latitude = 3°S

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Copy this diagram to show windward (wet) & leeward (dry) sides of mountain

H2O

desert

Aerosols in the atmosphere (video)

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60°N

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30°S

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60°N

60°S

30°S

30°N

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http://www.ssec.wisc.edu/data/us_comp/movie-large.php

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60°N

60°S

30°S

30°N

0°

60°N

60°S

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Weather you like it or not! (4m)National Geographic.com Weather 101

Air: consists of different gases, including H2O vapor, and other particles

• it has mass & volume and exerts pressure

• denser air has more pressure

5 Factors that affect weather:

1. Humidity: amount of water vapor in the air

2. condenses into clouds which can result in precipitation

3. Warm air holds more water vapor than cold air, so it’s more humid in the summertime!

dew point: temp. at which condensation occurs

(both in the air or on the ground)hygrometer: instrument used to measure relative humidity

2. Clouds form when H2O vapor cools

and condenses onto tiny particles in the air

satellite imagery

Wind map

AIR MASS GLOBE MAP

Pilots use them when flying from west to east to decrease travel time.

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Hyperlink: weather fronts (4:44m)

Warm Front

Tracking Map

FRONT SYMBOLS