1. Factors That Affect Climate
Weather vs. Climate

2. Weather vs. Climate Weather
condition of the atmosphere in one place during a short period of time.
In other words…what it’s like OUTSIDE, right HERE, right NOW
Climate
weather patterns typical for an area over a long period of time. (AVG.)

3. Creating Seasons Revolution Rotation Axial Tilt Orbit around the sun
Earth rotates on its axis - 24 hours – from west to east.
Axial Tilt
Earth is tilted at 23 ½ ° differing the amount of sunlight throughout the year.

4. Creating Seasons Equinox Solstice
March 21 and September 23, suns rays on the equator. Spring and Fall
Solstice
June 21, north hemisphere receives the most sun, Dec 22 Southern hemisphere receives most sun. Summer and Winter.

5. Creating Seasons

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

7. Earth’s TILT
This tilt results in uneven heating of the Earth’s surface.
“Direct” sunlight
“Indirect” sunlight

8. From TILT to SEASONS
As the Earth travels around the Sun, the tilt changes in relation to the Sun. Sometimes “toward” the Sun, sometimes “away”, and sometimes neither.
This creates a predictable cycle of warmer and cooler periods, or seasons.

9. Latitude Major change to climate Change as you move North to South
Equator = direct rays = hot
Poles = indirect rays = cold

10. Seasons
Because the direction of the tilt (“towards” or “away”) is opposite for the Northern and 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

11. Greenhouse Effect
RULE #1 OF NATURE – Energy can be either absorbed or transferred
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.

12. Distributing the Sun’s Heat - WIND
RULE #2 OF NATURE – Nature seeks balance (equilibrium)
Wind is the movement of air from High pressure to Low pressure
Air Pressure changes with temp.
“Hot” (more active) molecules need
room to move, so they spread
apart, meaning LESS molecules
in a given space (LOW pressure)
“Cold” (less active) molecules don’t
move as much, so they pack closer
together, meaning MORE
molecules in a given space (HIGH pressure)
HOT
air
RISES
COLD
air
SINKS

13. Eight Factors That Affect Climate
Continental Location Ocean Currents Wind Currents Storms
Latitude Air Pressure Mountain Barriers Elevation

14. Air Pressure Caused by unequal distribution of earths heat.
LP = warm, moist air rises → forms clouds → storms.
HP = cold dry air → sinks → stable and clear.

15. WIND – Sea Breeze
When the sun shines, land (solid) heats up faster than water (liquid) – remember RULE #1 ?
Only the top 2-3 inches of earth get warm, then the heat is reflected back to the air. (Why do dogs dig in the dirt?)
The warm air rises, creating LOW PRESSURE over the land during the early/mid-morning
This imbalance (RULE #2) creates a COOL wind blowing in from the water, called a SEA BREEZE L H

16. WIND – Land Breeze
When the sun sets, the process reverses and land cools off faster than water (RULE #1)
This creates COOLer air (HIGH pressure) over the land and WARMer air (LOW pressure) over the water at night
The WARM wind blowing out from the land is called a LAND BREEZE L H

17. Mountain Barriers a.k.a. - Orographic Precipitation
a.k.a. – Rain Shadow Effect
Windward side
Warm, moist air → up windward side → cool moist air drops precipitation
Leeward side
Warm dry air → down leeward side → little to no rain.

18. Precipitation due to changes in elevation
Moist air travels over land and approaches a steep rise in elevation
As the air is forced up the side of the rise, the air cools, causing precip. on the “windward” side of the mountain
As the (now dry) air continues over and down the “leeward” side of the mountain, it warms up and absorbs any available moisture, creating a “rain shadow desert”
Found in areas of mountains or other rapid elevation change

19. Elevation How far above sea level you are.
Every 1,000 feet temperature changes 3.5°F.

20. Altitude (Elevation)
Higher elevation = thinner air, therefore less air to hold heat makes it colder.
RULE – The HIGHER the elevation, the COLDER the temperatures.

21. Continental Location Water heats and cools more slowly than land.
Coastline areas have stable temperature.
Interiors of continent have extreme temperature changes.

22. Ocean Currents Warm-water currents -equator to the poles.
Cold water currents - poles to the equator.
Coriolis effect – The currents circular patterns are opposite of one another due to the Earth’s rotation.
Northern Hemisphere – clockwise
Southern Hemisphere – counter clockwise.

23. Water Currents
Most ocean currents are affected by global wind patterns blowing across the oceans.
Most
WARM
currents
flow
WEST
Most
COOL
currents
flow
EAST

24. Direction of Currents
Global wind and ocean currents transfer heat and moisture around the world, and help carry moisture from the oceans to the land
Warm water moving toward the land brings moisture (H2O)
Warm water moving parallel to the coast brings heat, no H2O
Cool water brings cool, dry air -> mild or desert climates

25. Wind Currents
Air in high pressure rushes into areas of low pressure – this causes wind.
Helps to distribute earth’s heat.
Coriolis effect

26. Storms Clashes between warm and cold air masses
Hurricanes – tropical storms moving heat from tropics.
Tornadoes – powerful funnel shaped spiraling air.

27. CLIMATES
The world is divides into three large climate zones, based on latitude.
 DRAW THIS !!!
Low Latitude (“Tropical”) climates – always hot
Mid Latitude (“Temperate”) climates – hot/cold seasons
High Latitude (“Polar”) climates – seasons either mild or extreme cold

28. Climate Zones
Climate zones are divided into regions with differences in two key characteristics:
Amount of moisture (rain), and
Typical temperature range through the year
These two characteristics are affected by balancing the effects of four factors:
Latitude
Altitude
Nearness to water
Direction of atmosphere and ocean currents
 WRITE THESE DOWN !

29. Latitude
Due to the Earth’s tilt, the amount of sun energy changes over the earth’s surface…
Polar (High Latitude) zone – either mild temps. or extreme cold
Temperate (Mid-Latitude) zone – seasonal, most varied climates
Tropical (Low Latitude) zone – year-round direct sunlight, always hot
RULE: The HIGHER the latitude, the COLDER the temps.

30. How it Works... Tropical Wet Climate
Latitude – in the tropics HOT
Altitude – low land doesn’t stop air flow until mtns. in the west
Nearness – flat land “acts coastal”, allows moisture inland
Direction – air flow
brings in warm, moist air
from the ocean which then hits the mountain and rains

31. Precipitation – Nature’s Thermostat
There are 3 basic causes for rain. They are:
Convection – due to evaporation and cooling
Sun’s energy causes surface water to evaporate and become humidity
As the day cools off, the air cools and condenses, causing storms and rain
Usually in tropical environments
Frontal – due to changes in temperature
Starts with warm, moist air at the surface and above
As a cold front approaches, it stays low, forcing the moist air aloft
This cools and condenses the air, creating rain on the “leading edge” of the front
Usually in mid-latitudes where warm and cold air systems collide