CHAPTER 11 WEATHER AND CLIMATE
CHAPTER 11
WEATHER AND CLIMATE
Learning Outcomes
You Will Learn:
• to differentiate between weather and climate
• about the use and siting of weather instruments
• to compare weather and climatic data to understand
weather and climatic variations
• about the distribution and characteristics of the
world’s major climatic types
• how weather and climate affect people positively and
negatively
Why is the weather important to you?
CLOTHES!
FOOD!
HOLIDAYS!
• Weather affects our daily lives.
• Weather affects the ways we lead our daily activities.
• Weather affects the types of houses we live in.
Why is the weather important to you?
What is the difference between weather and
climate?
Definition of Weather
• Conditions in the atmosphere of a
particular area at a particular point in
time.
• Short-term conditions.
• Changes all the time and varies from
place to place.
• Climate refers to the weather pattern of a place over a long period of time, usually 30 years or more
• Long- term conditions.
• Seldom change.
Definition of Climate
What’s the climate like?
Weather Climate
Short term Long Term
Daily, Weekly Usually 30 years or more
Changes all the time and varies from place
to place.
Seldom change.
What are the basic elements of weather and climate?
• The basic elements of weather
and climate:
Temperature
Rainfall
Wind
What is Temperature?
Temperature
Describe the temperature in the morning, at noon and evening yesterday
Definition of Temperature
• Temperature refers to the
degree of hotness or coldness
of the air
• It varies throughout the day in a
place
• It varies from place to place
It varies throughout the day in a place
It varies from place to place
Equator
• Places nearer the Equator are warmer throughout the year than places farther away from it
• The increase in distance away from the from the Equator is known as Latitude.
It varies from place to place
Mount Kenya
It varies from place to place
• Temperature gets cooler as we go to higher grounds
• As the Altitude gets higher, the Temperature gets lower
• Give me 1 location in Malaysia that is influence by Altitude.
It varies from place to place
How do we measure Temperature?
• Air temperature is measured with a thermometer
• The scale is in degree Celsius (OC)
• Daily maximum temperature refers to the highest temperature reading for the day
• Daily minimum temperature refers to the lowest temperature reading for the day
A Minimum and Maximum Thermometer ( Six’s Thermometer)
mercury and a metal index
Temperature rises> mercury expands
mercury pushes the index up
Maximum thermometer
Temperature falls > mercury
contracts and stays in place
Contains alcohol
Measure the minimum
temperature
Minimum thermometer
How do you reset t he thermometer?
Why is alcohol used?
How do we read the temperature using a Six’s thermometer?
• What is the minimum and maximum temperature shown in the thermometer on the right?
Minimum temp = 13 oC Maximum temp = 32 oC
• By taking the bottom of the index.
Where are the thermometers placed
to measure temperature?
•Stevenson Screen
•Describe the
Stevenson
Screen on the
right.
•Stevenson Screen
Parts Why
1 White in color reflects heat
2 Louvres allows air to flow freely through it
3 Raised above ground
shelters the instruments form the heat radiating from the ground
4 Face north and south
Do not get the direct heat from the sun
Where should a Stevenson Screen be
located and why?
•Describe the
locations of
the Stevenson
Screen on the
Where is the best location to place a Stevenson Screen in School
A: In an open field – Air will circulate easily in the Stevenson Screen as the Screen is in an open space and is far away from buildings. B: Within the school – Heat within the building may affect the instruments inside the Screen. – The Screen may be disturbed by people. Eg
People may open the Screen door and this will affect the reading of the instruments.
C: Under the trees – The Screen will be in the shade, protected from direct sunlight. – Air may not circulate freely under the trees. D: On the basketball court – Instruments inside the Screen may be affected by the heat from the ground. – People in the basketball court may disturb the Screen.
Ans: Choice A best fulfills the criteria set for the siting of a Stevenson Screen.
Learning Outcomes
You Will Learn:
• Definition of rainfall.
• How it is rainfall formed
• How is rainfall measured.
Rainfall
Why do we study rainfall?
Too much? Too little?
http://www.youtube.com/watch?v=Y1BgYeepNlE&feature=re
lated
Definition of rainfall
• refers to the amount of rain that an area receives over a period of time
•It is measured in millimetres (mm) or centimetres (cm)
How is rain formed
Evaporation
Transpiration
Condensation
Rain or snow
falls 1
2
3
4
How is rainfall measured?
• A rain gauge is an instrument used to measure rainfall
• Parts of a rain gauge:
Rain Gauge
Ground
Glass bottle
Funnel
Copper Cylinder
Outer Casing
Calculating Rainfall
• Daily rainfall refers to the amount of rain that
falls over 24 hours
• Monthly rainfall refers to the total amount of
rainwater collected throughout the month
• Annual rainfall is the total amount of rainwater
collected throughout the year
Rainfall Map(Refer to textbook page 142)
•Rainfall map
shows the
distribution of
annual rainfall
in a place for a
period of time
CVSS
•Refer to textbook page 142
isohyets •Name 1 location that has the same amount of rainfall as CVSS
•Name 1 location that has less amount of rainfall than CVSS
•Name 1 location that has more amount of rainfall than CVSS
• Temperature is displayed as a line graph in a climograph
• Rainfall is displayed as bar in a climograph
• Rain Gauge
• Look at the two photographs below, describe
the locations of the rain gauge?
• Discuss in pair: (5 minutes)
1. Which is the most suitable location to place a Rain Gauge. Give Two reasons for your answer
2. Explain why the other sites are not
suitable?
Learning Outcomes
You Will Learn:
• Definition of wind.
• How it is wind formed?
• How to read wind directions?
• Where should a wind vane be sited?
• How to read a wind rose?
Wind Why do we study wind?
Too much? Too Little?
What is wind?
• Wind is defined as the movement of air over
the surface of the Earth.
Definition of wind:
How is wind formed?
http://www.youtube.com/watch?v=itj-x1XhzQo&feature=related
• The Earth is heated up at a different
rate.
• Warm air expands and rises up while
cool air condenses and sinks.
• Low Pressure is formed when warm air
rise.
•Cool air will move in from area of high
pressure to replace the warm air that
rises.
•Wind if formed when cool air blows from
area of high to area of low pressure.
• Wind direction is given by the compass
point of North, South, East and
West.
• A wind vane is used to measure
the direction of the wind.
How is wind direction measured?
• The pointer on the wind vane points to
the direction that the wind is blowing
from.
How is wind direction measured?
SE N
• A wind vane is usually
placed on a high,
open place with little or
no obstruction to the
flow of wind
Where should the wind vane be sited to
measure the wind directions accurately?
Where should the wind vane be sited to
measure the wind directions accurately?
A
B
C
Learning Outcomes
You Will Learn:
• To compare weather and climatic data to
understand weather and climatic variations
• About the distribution and characteristics of
the world’s major climatic types
Major Climatic Types of the World
• Temperature and rainfall are commonly used to
classify different climates of the world
• Three broad types of the world’s climates
Tropical
Temperate
Polar
• A climograph is used to present the climatic data of a
place
Climograph:
Describe the key information that you can
derive from the climograph of Singapore
shown below.
Climograph:
1. Location of the place
2. Latitude of the place
3. Months ( J,F,M,A……..)
4. Temperature (o C )
5. Amount of Precipitation
(mm or cm)
1
5 4
3
2
Climograph:
• A line graph shows the mean monthly temperature during the year
• A bar graph shows the average precipitation for each month
Climograph:
• What is the average annual temperature for Singapore?
• What is the total annual rainfall for Singapore?
•What is the annual temperature range?
Major Climatic Types of the World- Tropical Climate
• Places with a tropic climate
Lie on or near the Equator In the region known as the Tropics,
between the Tropic of Cancer (23.5oN) and the Tropic of
Capricorn (23.5oS)
Major Climatic Types of the World- Tropical Climate
• Places with a tropic climate
Experience high temperatures ranging from 20oC to 30
oC
Receive almost the same amount of sunlight all year around
Receive high annual rainfall ranging from 1000 to 2000
millimetres or more
Has a small annual temperature range.
• Characteristics of places with a
tropical climate:
High temperature and high rainfall throughout the year
Hot and wet climate
eg Singapore, Malaysia, Brazil and Kenya
Major Climatic Types of the World- Temperate Climate
• Places with a temperate climate
Lie between the Tropic of Cancer (23.5oN) and Arctic Circle
(66.5oN), and between the Tropic of Capricorn (23.5
oS) and
Antarctic Circle (66.5oS)
Major Climatic Types of the World- Temperate Climate
• Places with a temperate climate
Experience four seasons every year: spring, summer, autumn
(or fall) and winter
Receive different amounts of sunlight in different periods of the
year hence, temperatures vary greatly throughout the year
Annual rainfall is moderate
(300 to 1000 millimetres)
• Characteristics of places with a
temperate climate
Low to Moderate temperatures depending
on the season
Moderate rainfall throughout the year
Examples: Korea, Japan and the United States
of America
Major Climatic Types of the World- Polar Climate
• Places with a polar climate
Lie between Arctic Circle (66.5oN) and the North Pole (90
oN),
and between Antarctic Circle (66.5oS) and the South Pole (90
oS)
Major Climatic Types of the World- Polar Climate
• Places with a polar climate
Experience only summer and winter
From March to September: the North Pole receives six months of
continual sunshine while the South Pole faces six months of darkness
Are very dry because the air lacks
water vapour for the formation
of clouds and rain or snow
• Characteristics of places with
a polar climate
Very low temperatures (often below
freezing point) and rainfall throughout
the year
eg Arctic, Antarctica, Northern
Canada and Siberia
• Guide to describe the climate of a place :
1. Describe the temperature.
2. Describe the total annual rainfall.
3. Describe the annual temperature range.
4. Describe any distinct rainfall or temperature if they are present. E.g. Hot and wet, four seasons
etc.
Practise time: Base on the climographs provided in the next slide: a. Describe the climate of the locations. b. Identify the type of climate associated with the locations.
Major Climatic Types of the World-
Major Climatic Types of the World-
Climograph 1 Climograph 2 Climograph 3
Major Climatic Types of the World-
Climograph 1
1. It has low to moderate temperature
depending on the season. In winter,
the temperature is around -10oC
and 22oC in the summer.
2. It has a low annual rainfall of less
than 1000mm
3. It has a large annual temperature
range of about 32 oC
4. It has 4 seasons.
5. It probably has a Temperate
climate.
Major Climatic Types of the World-
Climograph 2
1. It has high temperature averaging
27 degree Celsius.
2. It has a small annual temperature
range of about 2 to 3 degree
Celsius.
3. Its has high annual rainfall of more
than 2000mm
4. This place is hot and wet.
5. It has no season.
6. It probably has a Tropical
Equatorial climate.
Major Climatic Types of the World-
Climograph 3
1. It has very low temperature
throughout the whole year. ( -28oC
to - 3oC
2. It has very low rainfall throughout
the year with an annual rainfall of
less 300mm
3. It has a large annual temperature
range of about 25oC
4. It probably experience summer and
winter only
5. It probably has a Polar climate.
Learning Outcomes
You Will Learn:
• how weather and climate affect humans
positively and negatively.
How Weather and Climate Affect Us
• Study the photographs on the next slide 1st row to look at picture A
2nd row to look at picture B
3rd row to look at picture C
4th row to look at picture D
5th row to look at picture E
6th and 7th row to look at picture F
• Write down on the same piece of paper earlier:
Describe any activities or things that caught your attention on the photographs
Describe how they can be related to climate and weather?
How Weather and Climate Affect Us
• Daily activities Weather will determine whether we stay indoors or participate in outdoor activities.
How Weather and Climate Affect Us
• The Daily activities Weather will determine the types of activities we can engage in.
How Weather and Climate Affect Us
• Housing
The locations people choose to live in.
People prefer to live in places where it is neither too hot nor too cold.
How Weather and Climate Affect Us
• Housing The climate will also influence the types of housing people live in.
eg In many Southeast Asian countries, houses are built on stilts to prevent water from damaging their property during floods
How Weather and Climate Affect Us
• Tourism
The different climates experienced around the
world encourage tourism
How Weather and Climate Affect Us
•Production of electricity
Modern-day windmills harness the energy from the wind to generate electricity.
Solar energy is harness from the sun to generate electricity.
Hydroelectric power is harness from fast-moving water to generate electricity.
How Weather and Climate Affect Us
•Production of electricity
The wind, water and sun are known as renewable resources.
Can be naturally restored or replenished
Petroleum, natural gas and coal are non-renewable resources
How Weather and Climate Affect Us
• Food and water supplies
Different crops thrive under different climatic
conditions
How Weather and Climate Affect Us
• Food and water supplies
Changes in the climate will affect crops and
animals e.g a drought will destroy crops and reduce water
supplies which can result in a famine and affect
livestock
How Weather and Climate Affect Us
•Loss of lives and property
Extreme weather conditions can destroy many lives and property e.g. floods, heat waves and hurricanes
Spend 3 minutes to answer these questions
EXIT SLIP:
Describe any 3 ways that weather and climate
can affect us:
Something that I still do not understand is :