Download Chapter 4: Climate and Climate Change

What causes Climate ?
Text Book page # 470 - 477
Weather: The condition of Earth’s
atmosphere at a particular time and place.
 Climate: The average, year after year,
conditions of temperature, precipitation,
winds and clouds in an area.
 Microclimates: Climate conditions within
a small area that differ from those in the
surrounding area.
 Examples: parks, cities, areas near
lakes or ponds, gardens, etc.

Two main factors that causes Climate -
 Temperature
(cold or warm climate)
 Precipitation (dry or humid climate)
Factors Affecting Temperature
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Latitude
Altitude
Distance From Large Bodies of
Water
Ocean Currents
Latitude

Latitude: The distance in degrees
north or south of the equator.
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Based on latitude Earth’s surface can
be divided into 3 Temperature Zones
 Tropical Zones: warm climates
 Temperate Zones: ranging
temperatures
 Polar Zones: cold climates
Polar Zone
Polar Zone
Temperature Zones of Earth
Altitude

Altitude: elevation above sea level

High land areas have cooler climates
For example: Mt. Kilimanjaro, in East Africa is
covered with snow all year round although it is
near equator (3 degrees south latitude.
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Higher altitudes = cooler temperatures
Lower altitudes = warmer temperatures
Distance From Large Bodies of Water

Marine Climates: warmer winters and
cooler summers

Where? Much of the west coast of North
America, South America, and Europe.
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Continental Climates: colder winters and
warmer summers (extreme temperatures)

Where? Most of Canada and Russia, Central
United States.
Ocean Currents

Ocean Currents- Streams of water within
the oceans that move in regular patterns.

Oceans and lakes can affect temperatures /
climate

3 examples: Gulf Stream (warm water currents), North
Atlantic Drift (brings milder and humid air to Ireland and
Southern England) , California Current (cool water
current)
Major Ocean Surface Currents
Factors Affecting Precipitation
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Prevailing Winds
Presence of Mountain Ranges
Seasonal Winds
Prevailing Winds

movement of air masses caused by
directional winds in a region

The amount of water vapor in an air mass
influences how much rain or snow will fall

The amount of water vapor in the
prevailing wind depends on where the
wind comes from
Mountain Ranges
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Air forced up the
mountain cools,
condenses, and creates
clouds
Falls as precipitation on
windward side (The side
of the mountain that faces
the wind).
Leeward side (the side of
the mountain range that
faces away from the
oncoming wind) of
mountain has drier
conditions.
Seasonal Winds

Similar to sea or land breezes, but occurs
over wider area.
 Monsoons
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are type of seasonal winds.
Monsoons: Sea or land breeze over a large
region that changes direction with the seasons.
Thailand and part of India get most of the rain
from the summer monsoons.
The winter monsoons winds brings very little rain
to same regions.