Chapter 2 Gateway 1 P2

1. CHAPTER 2
VARIABLE WEATHER AND
CHANGING CLIMATE
A Continuing Challenge?
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2. CHAPTER 2
VARIABLE WEATHER AND CHANGING
CLIMATE
A Continuing Challenge?
In this Chapter you will explore three key
questions:
1.Why do different places experience different
weather and climate?
2.What is happening to the earth’s climate?
3.Is the weather becoming more extreme?
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3. RECAPITULATION FOR LESSON 1
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4. Recapitulation
a. What is the difference between
weather and climate?
Weather: Condition of atmosphere at a
particular place and specific time.
Climate: Average condition of the atmosphere of
a particular place over a long period of
time, usually 30 years.
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5. Gateway 1: Why do different places experience
different weather and climate?
a. What is the difference between weather and climate?
b. What are the elements of weather?
c. What are the climatic types and where are they
experienced?
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CHAPTER 2
VARIABLE WEATHER AND CHANGING CLIMATE

6. Gateway 1: Why do different places experience
different weather and climate?
a. What is the difference between weather and climate?
b. What are the elements of weather?
-Temperature, relative humidity, clouds, rainfall, air
pressure and wind.
c. What are the climatic types and where are they
experienced?
CHAPTER 3
VARIABLE WEATHER AND CHANGING CLIMATE
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7. b. What are the elements of weather?
Temperature
• Temperature: Degree of hotness or coldness of a
place.
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8. b. What are the elements of weather?
Temperature
• Factors influencing temperatures at different
locations.
- Latitude
- Altitude
- Distance from the sea
- Cloud cover
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9. Factors influencing temperatures at
different locations (LATITUDE)
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10. Factors influencing temperatures at different
locations (LATITUDE)
• Latitude: Distance of any point on the earth
measured north or south from the Equator.
– Imaginary horizontal lines east to west of Equator.
– Equator is at a latitude of 0°
North Pole is 90°N.
South Pole is 90°S.
• Latitude is the most important factor affecting
temperature!
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11. Factors influencing temperatures at
different locations (LATITUDE)
North Pole
Long, cold winters.
Short, cool summers.
Temperature range: -40 to 10°C
Singapore
Summer whole year round.
Temperature range: 23 to 34°C 11

12. Factors influencing temperatures at
different locations (LATITUDE)
The nearer the Equator, the higher the temperatures.
The further from the Equator, the lower the
temperatures.

13. b. What are the elements of weather?
Temperature
• Factors influencing temperatures at different
locations.
- Latitude
- Altitude
- Distance from the sea
- Cloud cover
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14. Factors influencing temperatures at
different locations (ALTITUDE)
• Altitude: Height of a place in relation to sea
level.
- General decrease of 6.5°C for every 1,000 m increase in
altitude.
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15. Factors influencing temperatures at
different locations (ALTITUDE)
How does altitude affect temperature?
• Distance from surface of the earth
- Longwave radiation is heat emitted by the earth after
absorbing shortwave radiation
- Most heat absorbed by the earth at lower altitudes ->
little heat at high altitudes -> cooler
• Density of air
- Air is less dense at higher altitudes -> absorb less long
wave radiation -> lower temperatures
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16. b. What are the elements of weather?
Temperature
• Factors influencing temperatures at different
locations.
- Latitude
- Altitude
- Distance from the sea
- Cloud cover
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17. Factors influencing temperatures at
different locations (DISTANCE FROM SEA)
LOCATION LATITUDE DISTANCE
FROM SEA
TEMPERATURE
RANGE
ANCHORAGE 61.1919° N 1 KM 20°C
FAIRBANKS 64.8378° N 420KM 40°C
The sea heating and cooling more slowly
than land influences the temperatures of
inland and coastal areas.
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18. Factors influencing temperatures at
different locations (DISTANCE FROM SEA)
Maritime Effect: Effect large ocean bodies have on
climate of coastal areas.
• Small temperature range
• Cool summers and warm winters
Continental Effect: Effect huge land surfaces have
on climate of inland areas.
• Large temperature range
• Hot summers and cold winters
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19. b. What are the elements of weather?
Temperature
• Factors influencing temperatures at different
locations.
- Latitude
- Altitude
- Distance from the sea
- Cloud cover
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20. Factors influencing temperatures at
different locations (CLOUD COVER)
• Cloud cover: Extent of sky covered by clouds
- Higher amount of cloud cover results in smaller daily
temperature range
Do you know?
The average daily temperature
range of the Sahara desert is
30°C? During very hot
months, the temperature can
be as high as 55°C in the day.
Temperatures may also fall to
below 0°C at night! 20

21. Factors influencing temperatures at
different locations (CLOUD COVER)
With cloud cover Without cloud cover
Day: Cooler
-> Clouds reflect sun’s energy back to
space.
Night: Warmer
-> Clouds prevent heat radiated from
ground from escaping.
Day: Warmer
-> Large amount of sun’s energy reaches
earth’s surface.
Night: Cooler
-> Allows more heat radiated from ground
to escape.
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22. Gateway 1: Why do different places experience
different weather and climate?
a. What is the difference between weather and climate?
b. What are the elements of weather?
-Temperature, relative humidity, clouds, rainfall, air
pressure and wind.
c. What are the climatic types and where are they
experienced?
CHAPTER 3 Recapitulation
VARIABLE WEATHER AND CHANGING CLIMATE
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