Climates of Earth

1. Climates of Earth Chapter Three

2. Earth-Sun Relationships • The seasons are determined by the Earth’s relationship to the sun • Reasons for the seasons • Earth’s Tilt • Earth’s Revolution around the sun

3. Tilt & Rotation • Tilt • The Earth is tilted at a 23.5* angle • The tilt affects how much sun an area receives • Tilted toward the sun– warmer temperatures • Tilted away from the sun – colder temperature • Rotation • Earth rotates on its axis from west to east • Axis – imaginary line running through Earth’s center from the N. Pole to the S. Pole • One rotation = 24 hours (1 day)

4. Revolution • Revolution – one full trip around the sun • One revolution = 365 ¼ days (1 year) • Earth revolves counterclockwise around sun • The position of the earth to the sun affects: • Seasons • Note: Seasons in the Northern Hemisphere are opposite in the Southern • Length of daylight • Temperature

5. Equinox – “equal” • The sun’s rays are directly over the Equator • Equal hours of daylight and sunlight • Occurs twice a year – Spring and Fall • Around March 21 & September 23 • Solstice – • Marks the beginning of Summer and Winter • June 21 – • Longest day of the year in the N. Hemisphere • sun is directly over the Tropic of Cancer • December 22 – • Shortest day of the year in the N. Hemisphere • sun is directly over the Tropic of Capricorn

6. Climate v. Weather Weather – • Condition of the atmosphere in one place during a SHORT period of time • Examples: raining, snowing, windy, etc. • Weather patterns that a place experiences over a LONG period of time • Examples: desert, tropical, tundra, etc. Climate –

7. Factors Affecting Climate • Zones of Latitude – • Low Latitude - • Most of this zone receives direct rays from the sun • Located around the Equator (30*N-30*S) • Creates Warm, Hot, Tropical climates • High Latitudes – • Located on the Poles of both hemispheres (60*N-90*N) (60*S-90*S) • Experiences cold to extreme cold year round

8. Midlatitudes – • Found in both the Northern and Southern Hemispheres (30*N-60*N) (30*S-60*S) • Experiences hot and cold • Seasonal changes • Example: the Midwest experiences 4 seasons • Elevation – • Air gets thinner as elevation rises • Thin air can NOT retain heat well • Temperature decreases by 3.5*F every 1,000 ft.

9. Wind Patterns – • Wind blows in specific patterns around the earth – prevailing winds • The direction wind blows is determined by the earth’s rotation • Northern Hemisphere – clockwise • Southern Hemisphere – counter clockwise • Known as the Coriolis Effect

10. Ocean Currents • Streams of hot or cold water moving in specific patterns • Cold water from the polar regions moves toward the equator • Warm water from the equator moves toward the poles • Affect coastal regions • Cold currents cool the land • warm currents warm the land • Topography • Landforms, or lack of, can affect climate • Examples: mountains, large bodies of water

11. World Climates • Five main climate regions • Tropical • Dry • Midlatitude • High Latitude • Highland

12. Tropical Climates • Found near the equator • Tropical Wet • Hot, humid and wet • Average precipitation – 80 in. per year • Average temperature – 80*F • Wide range of dense vegetation • Example: Rainforest (Amazon Rainforest – Brazil) • Tropical Dry • Dry winters and wet summers • Less vegetation, more grassland • Example: Savannas (Pampas – South America)

13. Dry Climates • Located in the low latitudes • Desert • Dry with sparse plant life • Avg. precipitation – less than 10 in. per year • Can be cold or hot - sandy or rocky • Example: Sahara Desert (northern Africa) • Steppe • On the edges of a desert • Average precipitation – 10-20 in. per year

14. Midlatitude Climates • Experience seasonal changes • Marine West Coast • Located along western coast lines • Ocean winds bring cool summers and winters • Vegetation - Coniferous and deciduous trees • Mediterranean • Primarily found around the Mediterranean Sea • Also located in SW Australia • Mild, rainy winters and hot, sunny summers

15. Humid Sub-tropical • Found in the Southern United States • Brings short, mild winters and nearly year round rain • Vegetation – • Prairies (inland grasslands), coniferous and deciduous forests • Humid Continental • Located in the interior of countries • Experience all four seasons • Vegetation – • Similar to Marine West Coast

16. High-Latitude Climates • Freezing Temperatures year round • Subarctic – • Located just south of the Arctic Circle • Winters are bitterly cold; summers short & cool • Permafrost – permanently frozen subsoil • Vegetation – coniferous trees • Tundra • Located near the North and South Poles • Winters are dark and bitterly cold, little sunlight • Vegetation – grasses, moss, lichens

17. Ice Cap • Covered in snow and ice • Snow is more than 2 miles thick • Vegetation - lichens • Average temperature – below freezing • Coldest temperature recorded was −128.6°F (Antarctica, 1983)

18. Highland Climate • High mountain areas • Found worldwide • Vegetation varies • Lower elevation – Mixed forests • Higher elevation – trees, shrubs, wildflowers • Temperature varies – depends on elevation