1. Climate & Vegetation
Chapter 3

2. Earth-Sun Relationships
Axis – imaginary line that run through the center of the Earth
Earth’s axis is tilted 23 ½ °
Earth’s tilt affects the climate since all places do not receive the same amount of direct sunlight.

3. Earth-Sun Relationships
Revolution – orbit around the sun
Earth’s revolution takes 365 ¼ days.
Revolution causes the changing seasons.

4. Earth-Sun Relationships
Rotation – spinning on its axis
The Earth’s rotation takes 24 hours.
Rotation causes day and night.

5. Earth-Sun Relationships
Equinox – either of the 2 times each year (spring and fall) when day and night are of nearly equal length everywhere on Earth
Solstice – either of the 2 times a year (summer and winter) when the sun appears directly overhead at noon to observers at the Tropics of Cancer and Capricorn

6. Weather vs. Climate
Weather - condition of the atmosphere at a particular location and time.
Climate – the term for weather conditions at a particular location over a long period of time

7. Weather Extremes
Hurricanes
Tornadoes
Blizzards
Droughts
Floods

8. Factors that Affect Climate
Latitude – the amount of direct sunlight affects climate
Places closer to the Equator receive more direct sunlight than areas closer to the poles which receive slanted rays.

9. Factors that Affect Climate
Landforms – mountains can block precipitation which can affect climate. This is called the orographic effect (rain shadow).
Ex. - Sierra Nevada range and the Mojave Desert
Windward side – wet
Leeward side - dry

10. Factors that Affect Climate
Wind currents
Prevailing winds are winds that blow in a fairly constant pattern.
The direction of the winds can determine what type of weather patterns an area will see.

12. Factors that Affect Climate
Ocean currents – cold and warm “rivers” of water known as currents, flow in the ocean
Cold currents cool the lands they pass while warm currents have a warming effect.
Ex. North Atlantic Drift flows near western Europe and gives the area a mild climate despite its northerly latitude

13. North Atlantic Drift

14. Factors that Affect Climate
Proximity to large bodies of water
Water is slower to heat and cool than land.
Water temperatures are more constant and uniform than land temperatures.
Temperatures of land areas located near oceans do not change as much as interior land areas.

15. Factors that Affect Climate
Proximity to large bodies of water
Example:
City Newport, OR Rapid City, SD
Location 44°N, 124°W 44°N, 103°W
Average Jan. 44° F Jan. 22° F
Temperatures July 57° F July 72° F

16. Factors that Affect Climate
Elevation – for every 1,000 feet gained, the temperature drops about 3.5° F.
Mt. Kilimanjaro in Africa is located near the Equator, but is covered with snow and ice

17. Changes in Climate
El Nino – warming of the waters off the west coast of South America
About every 7 years, prevailing easterly winds that blow over the central Pacific Ocean slow or reverse direction
The winds push warm ocean water toward the Americas causing floods and mudslides, Australia and Asia experience drought conditions
The reverse is called La Nina – this causes an increase in precipitation in places such as India and dryness along the Pacific coast of the Americas

19. Changes in Climate
Global Warming – although controversy exists over the causes of global warming, scientists agree temperatures are increasing
Some believe the cause is the greenhouse effect – layer of gases released by burning of coal and petroleum traps some solar energy, causing higher temperatures
Scientist predict that, if global warming continues, ice caps will melt, flooding some coastal areas, covering islands, and changing the global climate

21. 5 Major Climate Regions Tropical Dry Mid-Latitude High-Latitude
Highlands
See pages 60-61

22. Types of Precipitation
Convectional –hot, humid air rises and cools losing its ability to hold water (ex. Tropical rainforest)
Orographic – warm moist air is forced up when passing over high landforms
Frontal – 2 fronts of different temperatures meet

23. Convectional Precipitation

24. Frontal Precipitation

25. Orographic Precipitation

26. Four Types of Vegetation
Forest
Grassland
Desert
Tundra

27. Forest Tropical rainforest
Deciduous forest – broadleaf, such as maple and oak
Coniferous forest – cone bearing, evergreens
Chaparral

28. Forest

29. Grassland Tropical grasslands (savannas)
Temperate grasslands (prairies, steppes, pampas)

30. Grasslands

31. Desert
A desert can occur where there is a lack of precipitation, less than 10 inches a year.
Deserts can be cold, they do not have to be hot and sandy.
Vegetation – plants that can conserve water & withstand heat such as cacti & sagebrush

32. Desert

33. Tundra Alpine tundra Arctic tundra Vegetation – includes mosses
& lichens
Anaktuvuk Pass, Alaska