Transcript Folie 1

“Englisch als Arbeitssprache”
Unterrichtseinheiten zum Thema
“WORLD CLIMATE”
Walter Schöpf
HTL-Bregenz
Dornbirn, November 2005
1
World Climate
1st Atmospheric circulation and world climates
-Connection between atmospheric circulation and world
climates. (Figure, text, explanation)
-Importrant causes of wind developing: High-pressure, lowpressure, earth rotation (Figure, text, explanation)
2nd Factors affecting global temperatures
-Latitude and distance from the sea
-Prevailing winds, Ocean currents and Altitude
3rd Equatorial and tropical continental climates
-Equatorial climates and the daily pattern
-Tropical continental climates (climate graphs, figures, Text)
4th The monsoon, mediterranean and cold climates
-The monsoon
-Mediterranean and Cold climate (climate graphs, atlas, text)
5th Recapitulation
-Answer questions in groups and produce a card-game
-Play the -question and answer- game.
2
1st Atmospheric circulation and world climates
Any pattern of climate types that you could identify is mainly due
to the circulation of air in the atmosphere. In order to understand
this circulation, you need to be aware of the following processes:
1 If air next to the ground is heated, it expands, gets lighter an
rises.
Height of the air column
Height of the air column
after heating
before heating
It expands, gets
lighter and rises.
Height of the air
column before
heating
Height of the air
column after heating
Fill in the
underlined, and
the framed texts
into the suitable
boxes
Air next to the
ground is heated
0° (Equator)
Mark the right answer with a cross
Attend: The weight oft the air column above the ground is
0 the same as
0 more than
3
0 less than before the heating
1st Atmospheric circulation and world climates
K
Any pattern of climate types that you could identify is mainly due
to the circulation of air in the atmosphere. In order to understand
this circulation, you need to be aware of the following processes:
1 If air next to the ground is heated, it expands, gets lighter an
rises.
Height of the air column
Height of the air column
after heating
before heating
Tallness of the air
mm
Tallness of the air
mmm
Fill in the
underlined, and
the framed texts
into the suitable
boxes
0° (Equator)
Mark the right answer with a cross
Attention:
The weight oft the air column above the ground is
0 the same as
0 more than
0 less than before the heating
4
Mark the right answer with a cross
2 If air in the atmosphere is cooled, it becomes denser and
sinks, but it also means that the air column in 30° N and 30° S
is
0 higher
0 lower
than the air column at the equator, because it is
0 colder
0 warmer
Air pressure means the weight of the air column above the place
you quantify the pressure.
Fill the Letter L (low pressure) or H (high pressure) into the
suitable box. It means higher or lower pressure in relation to the
equator and 30° North or South. It might help you to imagine: A
ride on a hot-air balloon exactly in a height of 8 km at first at the
Equator and then in 30° north and south. At each place you
measure the pressure.
12
km
L
H
L
8
5
30° N
0° (equator)
30° S
Mark the right answer with a cross
K
2 If air in the atmosphere is cooled, it becomes denser and
sinks, but it also means that the air column in 30° N and 30° S
is
0 higher
0 lower
than the air column at the equator, because it is
0 colder
0 warmer
Air pressure means the weight of the air column above the place
you quantify the pressure.
Fill the Letter L (low pressure) or H (high pressure) into the
suitable box. It means higher or lower pressure in relation to the
equator and 30° North or South. It might help you to imagine: A
ride on a hot-air balloon exactly in a height of 8 km at first at the
Equator and then in 30° north and south. At each place you
measure the pressure.
12
km
L
H
L
8
6
30° N
0° (equator)
30° S
3 Wind, which is air in motion, blows from areas of high
pressure (H) to areas of low pressure (L). Therefore, the wind
in the atmosphere above 8 km blows from
0 the lower latitudes (30°N, 30°S) to the Equator
0 the Equator to the lower latitudes (30°N, 30°S)
12
km
L
H
30° N
H
L
0° (equator)
L
8
H
30° S
When this process is started, the air column at 30°N and 30°S
becomes 0 higher 0 lower and the air column at the equator
becomes 0 higher 0 lower, so that the atmospheric pressure at
the earth´s surface in 30°N and 30°S will 0 increase 0 decrease
as opposed to the atmospheric pressure at the earth´s surface at
the equator which will 0 increase 0 decrease.
Fill the Letter L (low pressure) or H (high pressure) into the
suitable box at the earth’s surface and complete the direction7 of
the wind flow with red arrows.
K
3 Wind, which is air in motion, blows from areas of high
pressure (H) to areas of low pressure (L). Therefore, the wind
in the atmosphere above 8 km blows from
0 the lower latitudes (30°N, 30°S) to the Equator
0 the Equator to the lower latitudes (30°N, 30°S)
12
km
L
H
30° N
H
L
0° (equator)
L
8
H
30° S
When this process is started, the air column at 30°N and 30°S
becomes 0 higher 0 lower and the air column at the equator
becomes 0 higher 0 lower, so that the atmospheric pressure at
the earth´s surface in 30°N and 30°S will 0 increase 0 decrease
as opposed to the atmospheric pressure at the earth´s surface at
the equator which will 0 increase 0 decrease.
Fill the Letter L (low pressure) or H (high pressure) into the
suitable box at the earth’s surface and complete the direction8 of
the wind flow with red arrows.
12
km
L
H
H
L
L
8
H
30° N
30° S
0° (Equator)
This circulation was discovered by Mr. Hadley, so it´s called
Hadley cell
4 The Coriolis force prevents air from moving directly from areas
of high pressure to areas of low pressure – otherwise the
prevailing wind in the Atlantic Ocean between the Equator and
30° north would be from the north, not the north east, so-called
the north-easterly trades.
9
K
12
km
L
H
H
L
L
8
H
30° N
30° S
0° (Equator)
This circulation was discovered by Mr. Hadley, so it´s called
Hadley cell
4 The Coriolis force prevents air from moving directly from areas
of high pressure to areas of low pressure – otherwise the
prevailing wind in the Atlantic Ocean between the Equator and
30° north would be from the north, not the north east, so-called
the north-easterly trades.
Draw the ground plan of the surface winds
10
Figure 13.1 shows the major areas of high and low pressure, and
the general circulation of the atmosphere.
a) Colorize Figure 13.1 like the master copy (transparency)
b) Fill in the framed winddirections into the suitable box of
Figure 13.1
Easterly winds
(South) westerly winds
North-easterly trades
South-easterly trades
(North) westerly winds
Easterly winds
11
- By midday, sun shines vertically giving maximum heat 2
- Warm air and water vapour
rise
3
- Sun´s rays heat the Earth´s surface 4
- Ground wet after previous day´s rain 1
3 Convection currents
1 Water vapour cools and condenses into water droplets
2 Cumulus clouds
2 After having lost most water, the dry and cold air is
spreading outwards from the Equator to …..
1 Cumulonimbus clouds give heavy rain, usually with
thunder and lightning
Ges. 18 Punkte möglich
a) Fill in the right numbers: O Ferrell cell
O Hadley cell
Ea
O Polar cell
b) Fill in the framed wind-directions into the
suitable box of Figure 13.1
Ea
Ea
North-easterly trades 6
Ea
(South) westerly winds 5
Easterly winds 4
Ea
(North) westerly winds 1
Ea
South-easterly trades 2
Easterly winds 3
12
Figure 13.1 shows the major areas of high and low pressure, and
the general circulation of the atmosphere.
a) Colorize Figure 13.1 like the master copy (overhead slide)
K
b) Fill in the framed winddirections into the suitable box of
Figure 13.1
Easterly winds
Easterly winds
South-easterly trades
North-easterly trades
(North) westerly winds
(South) westerly winds
Easterly winds
(South) westerly winds
North-easterly trades
South-easterly trades
(North) westerly winds
Easterly winds
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Convectional rainfall and thunderstorms at the Equator
Fill in the following sentences into the suitable boxes of Figure 12.10
1 Morning
1
2
3
1 Warm air and water vapour
rise
2 By midday, sun shines
vertically giving maximum heat
3 Ground wet after previous
day´s rain
4 Sun´s rays heat the Earth´s
surface
4
2 Early afternoon
1 Convection currents
2
2 Water vapour cools and
condenses into water droplets
3
1
3 Cumulus clouds
3 Late afternoon (4 p.m.)
1
2
1
1 After having lost most water,
the dry and cold air is
spreading outwards from the
Equator to …..
2 Cumulonimbus clouds give
heavy rain, usually with 14
thunder and lightning
Convectional rainfall and thunderstorms at the Equator
K
Fill in the following sentences into the suitable boxes of Figure 12.10
1 Morning
- Warm air and water vapour
rise
- By midday, sun shines
vertically giving maximum heat
- Ground wet after previous
day´s rain
- Sun´s rays heat the Earth´s
surface
2 Early afternoon
- Convection currents
- Water vapour cools and
condenses into water droplets
- Cumulus clouds
3 Late afternoon (4 p.m.)
- After having lost most water,
the dry and cold air is
spreading outwards from the
Equator to …..
- Cumulonimbus clouds give
heavy rain, usually with 15
thunder and lightning
Read the following description and show the cycles at the basic of
Figure13.1 and 12.10 as well as in your Atlas at page……
Verbal description to Figure 13.1
The circulation is controlled by the build-up of heat at the
Equator, which causes air to rise (convection currents) and low
pressure to form. As the rising air cools, it condenses to give
thunderstorms before spreading outwards from the Equator.
As the air becomes denser (at 30°N and 30°S), it descends to
form a high pressure belt and, as it gets warmer and drier, an
area of desert. Some of the descending air, on reaching the
ground, returns to the Equator as the trade winds. The remainder
moves away from the tropics (the westerlies) towards places like
Britain where, as warm, moist tropical air, it meets with colder
polar air and is forced to rise, creating low pressure and
depressions (… it will be done later).
This explanation is an oversimplified one (if it was not, then
weather forecasting would be quite easy!). Due to the Earth´s tilt
and rotation, the position of the overhead sun appears to change,
giving us our seasons. The northern hemisphere is hottest when
the sun appears to be above the Tropic of Cancer (21 June). At
this time, the pressure and wind belts move northwards. In
contrast, the southern hemisphere is hottest when the sun
appears to be over the Tropic of Capricorn (21 December), by
which time the pressure and wind belts have moved south. The
resultant changes in pressure and wind are responsible for the
seasonal contrasts in climates, such as the tropical continental
16
and the Mediterranean climate types.
Read the following description and show the cycles on the basis of Figure13.1 and 12.10 as well
as your Atlas at page……
Verbal description to Figure 13.1
K
The circulation is controlled by the build-up of heat at the Equator, which causes air to rise
(convection currents) and low pressure to form. As the rising air cools, it condenses to give
thunderstorms before spreading outwards from the Equator.
As the air becomes denser (at 30°N and 30°S), it descends to form a high pressure belt and, as it
gets warmer and drier, an area of desert. Some of the descending air, on reaching the ground,
returns to the Equator as the trade winds. The remainder moves away from the tropics (the
westerlies) towards places like Britain where, as warm, moist tropical air, it meets with colder polar
air and is forced to rise, creating low pressure and depressions (… it will be done later).
This explanation is an oversimplified one (if it was not, then weather forecasting would be quite
easy!). Due to the Earth´s tilt and rotation, the position of the overhead sun appears to change,
giving us our seasons. The northern hemisphere is hottest when the sun appears to be above the
Tropic of Cancer (21 June). At this time, the pressure and wind belts move northwards. In contrast,
the southern hemisphere is hottest when the sun appears to be over the Tropic of Capricorn (21
December), by which time the pressure and wind belts have moved south. The resultant changes
in pressure and wind are responsible for the seasonal contrasts in climates, such as the tropical
continental and the Mediterranean climate types.
Read the following description and show the cycles on the basis of Figure13.1 and 12.10 as well
as your Atlas at page……
Verbal description to Figure 13.1
The circulation is controlled by the build-up of heat at the Equator, which causes air to rise
(convection currents) and low pressure to form. As the rising air cools, it condenses to give
thunderstorms before spreading outwards from the Equator.
As the air becomes denser (at 30°N and 30°S), it descends to form a high pressure belt and, as it
gets warmer and drier, an area of desert. Some of the descending air, on reaching the ground,
returns to the Equator as the trade winds. The remainder moves away from the tropics (the
westerlies) towards places like Britain where, as warm, moist tropical air, it meets with colder polar
air and is forced to rise, creating low pressure and depressions (… it will be done later).
This explanation is an oversimplified one (if it was not, then weather forecasting would be quite
easy!). Due to the Earth´s tilt and rotation, the position of the overhead sun appears to change,
giving us our seasons. The northern hemisphere is hottest when the sun appears to be above the
Tropic of Cancer (21 June). At this time, the pressure and wind belts move northwards. In contrast,
the southern hemisphere is hottest when the sun appears to be over the Tropic of Capricorn (21
December), by which time the pressure and wind belts have moved south. The resultant changes
in pressure and wind are responsible for the seasonal contrasts in climates, such as the tropical
continental and the Mediterranean climate types.
17
Work in pairs and answer the following questions as a recapitulation:
K
a) Why is pressure:
- low at the Equator ?
- high about 30° from the Equator ?
- low at about 60° from the Equator ?
b) What is reponsible for this:
- the trade winds in the tropics
- the prevailing south-westerlies in Britain
- convectional rainfall on the Equator
c) - Draw a simple diagram to show the general circulation of the atmosphere. Your
diagram should show the three circulation cells.
- What relationship can you see between the circulation of the atmosphere and the
pattern of world climate types?
Work in pairs and answer the following questions as a recapitulation:
a) Why is pressure:
-low at the Equator
-high about 30° from the Equator
-low at about 60° from the Equator
b) How does this pattern of high and low pressure account for:
-the trade winds in the tropics
-the prevailing south-westerlies in Britain
-convectional rainfall on the Equator
c) - Draw a simple diagram to show the general circulation of the atmosphere. Your
diagram should show the three circulation cells.
- What relationship can you see between the circulation of the atmosphere and the
pattern of world climate types?
18
2nd Factors affecting global temperatures
Latitude: Places in the tropics, being nearer the Equator, are
much warmer than places towards the Poles.
Atmosphere
(dust, vapour)
Sun at a low angle AB a greater area to
heat up
Parallel and equal rays of
heat and light from the sun
Rays pass more quickly
through atmosphere at
Equator (Q) than nearer
poles (P)
Equator (sun overhead)
X-Y a smaller area to
heat up
The equatorial, tropical continental and monsoon climates are
therefore much warmer than places nearer to the poles. This is
due to the curvature of the Earth and the angle of the sun. At the
Equator the sun is always high in the sky. When it is overhead it
shines directly downwards, concentrating its heat into a small
area which will become very hot. In contrast, the sun is always
low in the sky towards the poles. This means that its heat is 19
2nd Factors affecting global temperatures
K
Latitude: Places in the tropics, being nearer the Equator, are much warmer than
places towards the Poles.
a) Colorize Figure 12.2 like the master copy (overhead slide)
b) Fill in the framed texts into the suitable boxes of Figure 12.2
Sun at a low angle A-B a greater
area to heat up
Parallel and equal rays of heat and
light from the sun
Atmosphere (dust, vapour)
Rays pass more quickly through
atmosphere at Equator (Q) than nearer
poles (P)
Equator (sun overhead) X-Y a smaller area
to heat up
Atmosphere
(dust, vapour)
Sun at a low angle
A-B a greater area
to heat up
Parallel and equal rays of heat
and light from the sun
Rays pass more quickly
through atmosphere at
Equator (Q) than nearer
poles (P)
Equator (sun overhead) XY a smaller area to heat
up
20
spread over a wide area, and so temperatures remain lower.
Notice also that the lower the angle of the sun, the greater the
amount of atmosphere through which the rays have to pass. This
means that more heat will be lost to gases, dust and cloud in the
atmosphere. This is why places in the south of Britain can expect
to be warmer, especially in summer, than places further north.
21
Fill in the missing phrases into the following text:
K
nearer to the poles / lower / atmosphere through which / low in
the sky / cloud / will become very hot / high in the sky./ north /
wide area
The equatorial, tropical continental and monsoon climates are therefore
much warmer than places……………. This is due to the curvature of the
Earth and the angle of the sun. At the Equator the sun is always
…………………. When it is overhead it shines directly downwards,
concentrating its heat into a small area which …………….. In contrast,
the sun is always ………….. towards the poles. This means that its heat is
spread over a ……………….., and so temperatures remain………….
Notice also that the lower the angle of the sun, the greater the amount of
…………………..the rays have to pass. This means that more heat will
be lost to gases, dust and ………….. in the atmosphere. This is why
places in the south of Britain can expect to be warmer, especially in
summer, than places further……………..
22
Distance from the sea: The sea (a liquid) is less dense than the
land (a solid) and can be heated to a greater depth. This means
that the sea takes much longer to heat up in summer than does
the land. Once warmed, however, the sea retains its heat for
much longer, and cools down more slowly than the land in winter.
This is why places that are inland are warmer in summer but
colder in winter than places on the coast. As Britain is
surrounded by the sea, it tends to get cool summers and mild
winters. The largest reservoir of heat in winter is the Atlantic
Ocean, even though it is still cold enough to die from hypothermia
within a few minutes should you fall into it. This explains why
western parts of Britain are warmer than places to the east in
winter.
23
Prevailing winds: Prevailing winds will bring warm weather if
they pass over warm surfaces (the land in summer, the sea in
winter) and cold weather if they blow across cold surfaces (the
land in winter, the sea in summer). As Britain´s prevailing winds
are from the south-west, they are cool in summer but warm (mild)
in winter.
Ocean currents: Many coastal areas are affected by ocean
currents. The North Atlantic Drift is a warm current of water which
originates in the Gulf of Mexico. It keeps the west coast of Britain
much warmer in winter than other places in similar latitudes.
Altitude: Temperatures decrease, on average, by 1°C for every
100 meters in height. As many parts of the Scottish Highlands are
over 1000 meters, they will be at least 10°C cooler than coastal
places. In fact, the wind chill factor will make them even colder,
and enables snow to lie for long periods during winter.
24
Fill in the phrases into the following text:
K
colder in winter / longer to heat up / you
Distance from the sea: The sea (a
fall / in summer / western / summers /
east / cools down more slowly / winters liquid) is less dense than the land (a solid) and
can be heated to a greater depth. This means
that the sea takes much ……………….in
summer than does the land. Once warmed,
however, the sea retains its heat for much longer,
and …………………….than the land in winter.
This is why places that are inland are warmer
………….but ……………..than places on the
coast. As Britain is surrounded by the sea, it
tends to get cool …………and mild…………….
The largest reservoir of heat in winter is the
Atlantic Ocean, even though it is still cold enough
to die from hypothermia within a few minutes
should ………...into it. This explains why ………..
parts of Britain are warmer than places to the
………….in winter.
Prevailing winds: Prevailing winds
Fill in the phrases into the following
text:
south-west / warm surfaces / warm /
cold weather
west coast / North Atlantic Drift / latitudes
long periods / decrease / 10°C cooler
will bring warm weather if they pass over
…………………(the land in summer, the
sea in winter) and …………………if they
blow across cold surfaces (the land in
winter, the sea in summer). As Britain´s
prevailing winds are from the………….,
they are cool in summer but……….(mild)
in winter. Ocean currents: Many
coastal areas are affected by ocean
currents. The …………………is a warm
current of water which originates in the
Gulf of Mexico. It keeps the …………. of
Britain much warmer in winter than other
places in similar…………….. Altitude:
Temperatures…………….., on average,
by 1°C for every 100 meters in height. As
many parts of the Scottish Highlands are
over 1000 meters, they will be at least
………………….than coastal places. In
fact, the wind chill factor will make 25
them
even colder, and enables snow to lie for
………………during winter.
Work in pairs and answer the following questions as a recapitulation:
K
-Why do global temperatures increase towards the Equator?
- Why do places in the centre of continents have warmer summers and colder
winters than places that have a coastal location?
-Why are prevailing winds from the sea:
x warmer in winter
x cooler in summer?
-How can ocean currents affect the temperatures of coastal areas?
-Why can snow be found in some places on the Equator?
Work in pairs and answer the following questions as a recapitulation:
-Why do global temperatures increase towards the Equator?
- Why do places in the centre of continents have warmer summers and colder
winters than places that have a coastal location?
-Why are prevailing winds from the sea:
x warmer in winter
x cooler in summer?
-How can ocean currents affect the temperatures of coastal areas?
-Why can snow be found in some places on the Equator?
Work in pairs and answer the following questions as a recapitulation:
-Why do global temperatures increase towards the Equator?
- Why do places in the centre of continents have warmer summers and colder
winters than places that have a coastal location?
-Why are prevailing winds from the sea:
x warmer in winter
x cooler in summer?
-How can ocean currents affect the temperatures of coastal areas?
-Why can snow be found in some places on the Equator?
26
3rd Equatorial and tropical continental climates
Equatorial
Places with an equatorial climate lie within 5° either side of the
Equator. The main areas are the large drainage basins of the
Amazon (South America) and Congo (Africa) rivers and the
extreme south-east of Asia (Fig. 13.2).
a) Colorize the Equatorial climates in Figure 13.2 like the
master copy (overhead slide) and name the main areas of
Equatorial climates
b) Read the following text, analyze the climate graph of
Manaus and loklisize Manaus in your Atlas and in Figure
13.2
Manaus (Brazil) 3°S; Altitude 44 m
Figure 13.3 is a climate
graph for Manaus which
is located 3° south of the
Equator and in the centre
of the Amazon basin in
Brazil. It shows that
temperatures are both
high and constant
throughout the year. The
small annual range of
2°C is due to the sun
always being at a high
angle in the sky, even if
not always directly
overhead (Fig. 12.2).
Annual range of temperature 2°C
Annual precipitation 2104 mm
27
K
28
b) Read the following text, analyze the climate
graph of Manaus and localize Manaus in your
Atlas and in Figure 13.2
Manaus (Brazil) 3°S; Altitude 44 m; Annual
range of temperature 2°C ; Annual precipitation
2104 mm
K
Figure 13.3 is a climate graph for Manaus which is
located 3° south of the Equator and in the centre of
the Amazon basin in Brazil. It shows that
temperatures are both high and constant throughout
the year. The small annual range of 2°C is due to the
sun always being at a high angle in the sky, even if
not always directly overhead (Fig. 12.2).
b) Read the following text, analyze the climate
graph of Manaus and localize Manaus in your
Atlas and in Figure 13.2
Manaus (Brazil) 3°S; Altitude 44 m; Annual
range of temperature 2°C ; Annual precipitation
2104 mm
Figure 13.3 is a climate graph for Manaus which is
located 3° south of the Equator and in the centre of
the Amazon basin in Brazil. It shows that
temperatures are both high and constant throughout
the year. The small annual range of 2°C is due to the
sun always being at a high angle in the sky, even if
not always directly overhead (Fig. 12.2).
b) Read the following text, analyze the
climate graph of Manaus and localize
Manaus in your Atlas and in Figure 13.2
Manaus (Brazil) 3°S; Altitude 44 m; Annual
range of temperature 2°C ; Annual precipitation
2104 mm
Figure 13.3 is a climate graph for Manaus which is
located 3° south of the Equator and in the centre of
the Amazon basin in Brazil. It shows that
temperatures are both high and constant throughout
the year. The small annual range of 2°C is due to the
sun always being at a high angle in the sky, even if
not always directly overhead (Fig. 12.2).
29
Work in pairs: Read the following text and answer the
questions:
a) Look for the doldrums in your Atlas and write down the
German word: ……………..
b) Why are the winds generally light?: …………
c) The dryer month in Manaus are in July, August and
September, why?? ……………………
d) Characterise the equatorial climate: ……….
Equatorial areas have annual rainfall totals in excess of 2000 mm,
mainly due to convectional thunderstorms which occur during
most afternoons throughout the year (Fig. 12.10). These storms
are due to the convergence of warm air (the trade winds). The
warm air is forced to rise, creating an area of low pressure and
giving heavy rain (Fig. 13.1) .
Some places, like Manaus, may have two or three drier, but not
dry, months when the sun is overhead at the opposite tropic
(which is Cancer in the case of Manaus), and most rain when the
sun is closer to being overhead. Winds are generally light (the
doldrums are areas of calm over equatorial oceans) and variable
(there are no prevailing winds, Figure 13.1). The equatorial
climate is characterised by its high humidity, a lack of seasonal
change, and a daily weather pattern that remains remarkably
uniform throughout the year.
30
Work in pairs: Read the following text and answer the questions:
K
a) Look for the doldrums in your Atlas and write down the German word: …
b) Why are the winds generally light?: …………
c) The dryer month in Manaus are in July, August and September, why?? …
d) Characterise the equatorial climate: ……….
Equatorial areas have annual rainfall totals in excess of 2000 mm, mainly due to
convectional thunderstorms which occur during most afternoons throughout the year
(Fig. 12.10). These storms are due to the convergence of warm air (the trade winds).
The warm air is forced to rise, creating an area of low pressure and giving heavy rain
(Fig. 13.1) .
Some places, like Manaus, may have two or three drier, but not dry, months when
the sun is overhead at the opposite tropic (which is Cancer in the case of Manaus),
and most rain when the sun is closer to being overhead. Winds are generally light
(the doldrums are areas of calm over equatorial oceans) and variable (there are no
prevailing winds, Figure 13.1). The equatorial climate is characterised by its high
humidity, a lack of seasonal change, and a daily weather pattern that remains
remarkably uniform throughout the year.
Work in pairs: Read the following text and answer the questions:
a) Look for the doldrums in your Atlas and write down the German word: …
b) Why are the winds generally light?: …………
c) The dryer month in Manaus are in July, August and September, why?? …
d) Characterise the equatorial climate: ……….
Equatorial areas have annual rainfall totals in excess of 2000 mm, mainly due to
convectional thunderstorms which occur during most afternoons throughout the year
(Fig. 12.10). These storms are due to the convergence of warm air (the trade winds).
The warm air is forced to rise, creating an area of low pressure and giving heavy rain
(Fig. 13.1) .
Some places, like Manaus, may have two or three drier, but not dry, months when
the sun is overhead at the opposite tropic (which is Cancer in the case of Manaus),
and most rain when the sun is closer to being overhead. Winds are generally light
(the doldrums are areas of calm over equatorial oceans) and variable (there are no
prevailing winds, Figure 13.1). The equatorial climate is characterised by its high
humidity, a lack of seasonal change, and a daily weather pattern that remains 31
remarkably uniform throughout the year.
The daily pattern
One day is very much like another, with places receiving 12
hours of daylight and 12 hours of darkness. The sun rises at 0600
hours and its heat soon evaporates the morning mist, the heavy
overnight dew, and any moisture remaining from the previous
afternoon´s storm. Even by 0800 hours temperatures are as high
as 25°C and by noon, when the sun is near to a vertical position,
they reach 33°C. The high temperatures cause air to rise in
powerful convection currents. The rising air, which is very moist
due to rapid evapotranspiration from swamps, rivers and the
rainforest vegetation (Figure 13.4),
Cools on reaching higher altitudes. When it cools to its dew point
– the temperature at which water vapour condenses back into
water droplets –large cumulus clouds develop. By mid-afternoon
these clouds have grown into black, towering cumulonimbus
which produce torrential downpours, accompanied by thunder
and lightning.
Such storms soon cease, leaving the air calm. By sunset, at
about 1800 hours, the clouds have already begun to break up.
Nights are warm (23°C) and very humid. As one nineteenthcentury botanist wrote while exploring the Amazon area, ´Such
32
conditions are similar throughout the year, seemingly one long
tropical day´.
K
Work in pairs: Read the following
text and summarize the daily
pattern of the Equatorial Climates
in some few short points: ……….
The daily pattern: One day is very much like another, with places receiving 12 hours of daylight
and 12 hours of darkness. The sun rises at 0600 hours and its heat soon evaporates the morning
mist, the heavy overnight dew, and any moisture remaining from the previous afternoon´s storm.
Even by 0800 hours temperatures are as high as 25°C and by noon, when the sun is near to a
vertical position, they reach 33°C. The high temperatures cause air to rise in powerful convection
currents. The rising air, which is very moist due to rapid evapotranspiration from swamps, rivers
and the rainforest vegetation (Figure 13.4),
Cools on reaching higher altitudes. When it cools to its dew point – the temperature at which water
vapour condenses back into water droplets –large cumulus clouds develop. By mid-afternoon these
clouds have grown into black, towering cumulonimbus which produce torrential downpours,
accompanied by thunder and lightning. Such storms soon cease, leaving the air calm. By sunset,
at about 1800 hours, the clouds have already begun to break up. Nights are warm (23°C) and very
humid. As one nineteenth-century botanist wrote while exploring the Amazon area, ´Such
conditions are similar throughout the year, seemingly one long tropical day´.
Work in pairs: Read the following
text and summarize the daily
pattern of the Equatorial Climates
in some few short points: ……….
The daily pattern: One day is very much like another, with places receiving 12 hours of daylight
and 12 hours of darkness. The sun rises at 0600 hours and its heat soon evaporates the morning
mist, the heavy overnight dew, and any moisture remaining from the previous afternoon´s storm.
Even by 0800 hours temperatures are as high as 25°C and by noon, when the sun is near to a
vertical position, they reach 33°C. The high temperatures cause air to rise in powerful convection
currents. The rising air, which is very moist due to rapid evapotranspiration from swamps, rivers
and the rainforest vegetation (Figure 13.4),
Cools on reaching higher altitudes. When it cools to its dew point – the temperature at which water
vapour condenses back into water droplets –large cumulus clouds develop. By mid-afternoon these
clouds have grown into black, towering cumulonimbus which produce torrential downpours,
accompanied by thunder and lightning. Such storms soon cease, leaving the air calm. By sunset,
33
at about 1800 hours, the clouds have already begun to break up. Nights are warm (23°C) and very
humid. As one nineteenth-century botanist wrote while exploring the Amazon area, ´Such
conditions are similar throughout the year, seemingly one long tropical day´.
Tropical continental (interior)
This climate is found in central parts of continents, away from
coasts, and mainly between latitudes 5° and 15° north and south
of the Equator (Figure 13.2). This includes the Brazilian Highlands
and parts of Venezuela (South America), northern Australia, and a
large semi-circle surrounding the Congo basin (Africa). This last
area includes Kenya which, although straddling the Equator, lies
at an altitude too high to share the main features of the equatorial
climate. The main characteristic of the tropical continental climate,
as illustrated by the climate graph for Timbuktu in southern Mali
(Figure 13.5), is alternate wet and dry seasons,
Timbuktu (Mali) 16°50´N; Altitude 250 m
Annual range of temperature 13°C
Annual precipitation 285 mm
34
a) Colorize the tropical continental climates in Figure 13.2 like the master copy (overhead
slide) and name the main areas of Equatorial climates
b) Read the following text, analyze the climate graph of Timbuktu and localize Timbuktu in
your Atlas and in Figure 13.2
Timbuktu (Mali) 16°50´N; Altitude 250
Tropical continental (interior)
m Annual range of temperature 13°C
Annual precipitation 285 mm
This climate is found in central parts of
continents, away from coasts, and mainly
between latitudes 5° and 15° north and south
of the Equator (Figure 13.2). This includes the
Brazilian Highlands and parts of Venezuela
(South America), northern Australia, and a
large semi-circle surrounding the Congo basin
(Africa). This last area includes Kenya which,
although straddling the Equator, lies at an
altitude too high to share the main features of
the equatorial climate. The main characteristic
of the tropical continental climate, as illustrated
by the climate graph for Timbuktu in southern
Mali (Figure 13.5), is alternate wet and dry
seasons,
a) Colorize the tropical continental climates in Figure 13.2 like the master copy (overhead
slide) and name the main areas of Equatorial climates
b) Read the following text, analyze the climate graph of Timbuktu and localize Timbuktu in
your Atlas and in Figure 13.2
Tropical continental (interior)
This climate is found in central parts of
continents, away from coasts, and mainly
between latitudes 5° and 15° north and south
of the Equator (Figure 13.2). This includes the
Brazilian Highlands and parts of Venezuela
(South America), northern Australia, and a
large semi-circle surrounding the Congo basin
(Africa). This last area includes Kenya which,
although straddling the Equator, lies at an
altitude too high to share the main features of
the equatorial climate. The main characteristic
of the tropical continental climate, as illustrated
by the climate graph for Timbuktu in southern
Mali (Figure 13.5), is alternate wet and dry
seasons,
Timbuktu (Mali) 16°50´N; Altitude 250
m Annual range of temperature 13°C
Annual precipitation 285 mm
35
which are caused by the apparent movement of the overhead sun
(Figure 13.6). The hot, wet season occurs at Timbuktu when the
sun is overhead in the northern hemisphere (21 June-Figure
13.6b). Temperatures rise as the sun takes a more vertical
position and because places are too far inland to be affected by
any moderating influence of the sea. However, temperatures fall
slightly in July and August as cloud cover and rainfall increase.
The frequent afternoon convectional thunderstorms mean that the
climate resembles, at this time of year, that of equatorial areas.
Unfortunately both the length of the rainy season and the total
amounts of rain are unreliable and many areas, especially those
with increasing distance from the Equator in Africa, have
experienced severe drought in recent years (Case Study 13A).
The dry, slightly cooler season at Timbuktu occurs when the sun
is overhead in the opposite (i.e. southern) hemisphere (21
December – Figure 13.6d).
Timbuktu
Timbuktu
Timbuktu
Timbuktu
36
The apparent movement of the sun southwards is accompanied
by the movement of the equatorial low pressure and the global
wind belts (Figure 13.6 and page 210) so that the area is now
influenced by the prevailing trade winds. The trade winds, blowing
from the east, will have shed any moisture long before they reach
these inland areas. Indeed, as the sun is still at a sufficiently high
angle to give quite high temperatures, the climate here at this
time of year remembers that of the hot deserts. (Remember that
for places south of the Equator, the seasonal pattern described
here is reversed.)
37
Read the following description and explain the whole process on the
basis of Figure13.6 and your Atlas at page……
K
…which are caused by the apparent movement of the overhead sun (Figure 13.6). The hot, wet
season occurs at Timbuktu when the sun is overhead in the northern hemisphere (21 June-Figure
13.6b). Temperatures rise as the sun takes a more vertical position and because places are too far
inland to be affected by any moderating influence of the sea. However, temperatures fall slightly in
July and August as cloud cover and rainfall increase. The frequent afternoon convectional
thunderstorms mean that the climate resembles, at this time of year, that of equatorial areas.
Unfortunately both the length of the rainy season and the total amounts of rain are unreliable and
many areas, especially those with increasing distance from the Equator in Africa, have experienced
severe drought in recent years (Case Study 13A).
The dry, slightly cooler season at Timbuktu occurs when the sun is overhead in the opposite (i.e.
southern) hemisphere (21 December – Figure 13.6d).
The apparent movement of the sun southwards is accompanied by the movement of the equatorial
low pressure and the global wind belts (Figure 13.6 and page 210) so that the area is now
influenced by the prevailing trade winds. The trade winds, blowing from the east, will have shed
any moisture long before they reach these inland areas. Indeed, as the sun is still at a sufficiently
high angle to give quite high temperatures, the climate here at this time of year remembers that of
the hot deserts. (Remember that for places south of the Equator, the seasonal pattern described
here is reversed.)
Timbuktu
Timbuktu
Timbuktu
Timbuktu
38
4th The monsoon, mediterranean and cold climates
The monsoon
The word monsoon means “a season”. In much of Southeast
Asia, as seen in the climate graph for Mumbai (Bombay) (Figure
13.7), there are two seasons. These, the so-called south-west
monsoon and the north-east monsoon, result from the reversal in
the direction of the prevailing wind.
39
a) Colorize the monsoon climates in Figure 13.2
like the master copy (overhead slide) and name
the main areas of monsoon climates climates
K
b) Read the following text, analyze the climate
graph of Mumbai and localize Mumbai in your
Atlas and in Figure 13.2
The monsoon
The word monsoon means “a season”. In much of
Southeast Asia, as seen in the climate graph for
Mumbai (Bombay) (Figure 13.7), there are two
seasons. These, the so-called south-west monsoon
and the north-east monsoon, result from the
reversal in the direction of the prevailing wind.
a) Colorize the monsoon climates in Figure 13.2
like the master copy (overhead slide) and name
the main areas of monsoon climates climates
b) Read the following text, analyze the climate
graph of Mumbai and localize Mumbai in your
Atlas and in Figure 13.2
The monsoon
The word monsoon means “a season”. In much of
Southeast Asia, as seen in the climate graph for
Mumbai (Bombay) (Figure 13.7), there are two
seasons. These, the so-called south-west monsoon
and the north-east monsoon, result from the
reversal in the direction of the prevailing wind.
40
The south-west
monsoon (Figure 13.8)
the sun appears to be
overhead at the Tropic
of Cancer in June.
Places to the north of
the Himalayas, which
are a long way from any
moderating influence of
the sea, become
extremely hot. As the hot
air rises, an extensive
area of low pressure is
formed and warm, moist
air is drawn northwards
from the Indian Ocean.
Where the air is forced
to rise over mountains
(e.g. the Western Ghats
and the Himalayas), it
gives large amounts of
relief rainfall (Figure
12.8).
Mumbai gets over 2000 mm in
five months and Cherrapunji,
reputed to be the wettest place
on Earth, 14000 mm. The rain,
ideal for rice (Case Study 7),
can cause extensive flooding in
the Ganges basin, while places
41
north of the Himalayas, being in
the rainshadow, remain dry.
Read the following description and
explain the whole process on the
basis of Figure13.8, 12.8 and your
Atlas at page……
The south-west monsoon (Figure 13.8)
the sun appears to be overhead at the
Tropic of Cancer in June. Places to the
north of the Himalayas, which are a long
way from any moderating influence of the
sea, become extremely hot. As the hot air
rises, an extensive area of low pressure is
formed and warm, moist air is drawn
northwards from the Indian Ocean. Where
the air is forced to rise over mountains (e.g.
the Western Ghats and the Himalayas), it
gives large amounts of relief rainfall (Figure
12.8).
K
Fill in the following sentences into the
suitable boxes of Figure 12.8
Prevailing winds pick
up moisture form the
sea (evaporation)
Air descend, warms,
and is able to pick up
moisture
Air is cooled to dew point.
Condensation occurs. Clouds and
eventually rain are formed
Winds forced to rise
by mountains. Rising
air cools
Air is cooled to dew point.
Condensation occurs. Clouds and
eventually rain are formed
Winds forced to rise
by mountains. Rising
air cools
Prevailing
winds pick up
moisture form
Air descend, warms,
and is able to pick up
moisture
Mumbai gets over 2000
mm in five months and
Cherrapunji, reputed to be
the wettest place on Earth,
14000 mm. The rain, ideal
for rice (Case Study 7), can
cause extensive flooding in
the Ganges basin, while
places north of the
Himalayas, being in the rain
shadow, remain dry.
42
The north-east
monsoon (Figure 13.9)
During the northern
winter, the overhead son
moves southwards.
Places to the north of the
Himalayas now become
very cold and an
extensive area of high
pressure develops.
Winds blow outwards
from the high pressure
area but, because they
originate in a dry area,
they give only small
amounts of rain as they
cross India – Mumbai, for
example, only receives
45 mm in seven months.
By the end of the ´dry´
season, many places are
at risk of drought.
43
Read the following description and explain
the whole process on the basis of
Figure13.9 and your Atlas at page……
The north-east monsoon (Figure 13.9) During
the northern winter, the overhead son moves
southwards. Places to the north of the
Himalayas now become very cold and an
extensive area of high pressure develops.
Winds blow outwards from the high pressure
area but, because they originate in a dry area,
they give only small amounts of rain as they
cross India – Mumbai, for example, only
receives 45 mm in seven months. By the end of
the ´dry´ season, many places are at risk of
drought.
K
Read the following description and explain
the whole process on the basis of
Figure13.9 and your Atlas at page……
The north-east monsoon (Figure 13.9) During
the northern winter, the overhead son moves
southwards. Places to the north of the
Himalayas now become very cold and an
extensive area of high pressure develops.
Winds blow outwards from the high pressure
area but, because they originate in a dry area,
they give only small amounts of rain as they
cross India – Mumbai, for example, only
receives 45 mm in seven months. By the end of
the ´dry´ season, many places are at risk of
drought.
44
Mediterranean
Places with a Mediterranean climate are found on the west coast
of continents between latitudes 30° an 40° north an south of the
Equator (Figure 13.2) Apart from the area surrounding the
Mediterranean Sea, where the climate does extend inland, this
climate also occurs in California, central Chile, around Cape Town
in South Africa and in parts of southern Australia. The climate is
characterised by hot, dry summers and warm, wet winters, as
shown by the climate graph for Rom.
Summers are hot . This is partly because the sun is at a high
angle in the sky (though never directly overhead) and the
prevailing winds blow from the warm land. Places next to oceans
(but not those around the Mediterranean Sea) are cooler due to
the moderating influence of the sea (San Francisco is no warmer
than southern England). As the wind also blows across a dry land
surface, it is unable to pick up much moisture. Apart from an
occasional thunderstorm, most places have several months of dry
and sunny weather.
Winters are warm, for although the sun is lower in the sky, it is still
higher than places further from the Equator (like Britain).
However, the prevailing winds have reversed direction and now
blow from the sea. This helps to keep coastal areas warm, and
also brings warm, moist air which, as it is forced to rise over the
many coastal mountains, gives large amounts of relief rainfall
(Figure 12.8) Even so, wet days are usually separated by several
that are warm and sunny.
45
a) Colorize the Mediterranean climates in Figure 13.2 like the master copy (overhead slide)
and name the main areas of Mediterranean climates
K
b) Read the following text, analyze the climate graph of Rom and localize Rom in your Atlas
and in Figure 13.2
Mediterranean
Places with a Mediterranean climate are found on the west coast of continents between latitudes
30° an 40° north an south of the Equator (Figure 13.2) Apart from the area surrounding the
Mediterranean Sea, where the climate does extend inland, this climate also occurs in California,
central Chile, around Cape Town in South Africa and in parts of southern Australia. The climate is
characterised by hot, dry summers and warm, wet winters, as shown by the climate graph for Rom.
Summers are hot . This is partly because the sun is at a high angle in the sky (though never
directly overhead) and the prevailing winds blow from the warm land. Places next to oceans (but
not those around the Mediterranean Sea) are cooler due to the moderating influence of the sea
(San Francisco is no warmer than southern England). As the wind also blows across a dry land
surface, it is unable to pick up much moisture. Apart from an occasional thunderstorm, most places
have several months of dry and sunny weather.
Winters are warm, for although the sun is lower in the sky, it is still higher than places further from
the Equator (like Britain). However, the prevailing winds have reversed direction and now blow from
the sea. This helps to keep coastal areas warm, and also brings warm, moist air which, as it is
forced to rise over the many coastal mountains, gives large amounts of relief rainfall (Figure 12.8)
Even so, wet days are usually separated by several that are warm and sunny.
a) Colorize the Mediterranean climates in Figure 13.2 like the master copy (overhead slide)
and name the main areas of Mediterranean climates
b) Read the following text, analyze the climate graph of Rom and localize Rom in your Atlas
and in Figure 13.2
Mediterranean
Places with a Mediterranean climate are found on the west coast of continents between latitudes
30° an 40° north an south of the Equator (Figure 13.2) Apart from the area surrounding the
Mediterranean Sea, where the climate does extend inland, this climate also occurs in California,
central Chile, around Cape Town in South Africa and in parts of southern Australia. The climate is
characterised by hot, dry summers and warm, wet winters, as shown by the climate graph for Rom.
Summers are hot . This is partly because the sun is at a high angle in the sky (though never
directly overhead) and the prevailing winds blow from the warm land. Places next to oceans (but
not those around the Mediterranean Sea) are cooler due to the moderating influence of the sea
(San Francisco is no warmer than southern England). As the wind also blows across a dry land
surface, it is unable to pick up much moisture. Apart from an occasional thunderstorm, most places
have several months of dry and sunny weather.
Winters are warm, for although the sun is lower in the sky, it is still higher than places further from
the Equator (like Britain). However, the prevailing winds have reversed direction and now blow from
the sea. This helps to keep coastal areas warm, and also brings warm, moist air which, as it is
forced to rise over the many coastal mountains, gives large amounts of relief rainfall (Figure 12.8)
46
Even so, wet days are usually separated by several that are warm and sunny.
Cold climate
The cold climate is found to
the pole ward side of 60°N in
Eurasia, where it extends from
Scandinavia across Russia to
the Pacific, and across North
America, central Alaska and
northern Canada (Figure
13.2). The graph for Fairbanks
shows the large annual range
in temperature that typifies
this type of climate. Winters
are very long, dark and
extremely cold. This is partly due to the northerly latitude which,
for places within the Arctic Circle, means a period of time when
the sun fails to rise above the horizon, and partly due to the
distance from any moderating influence of the sea. Strong winds
can lower temperatures, increase the wind-chill factor and bring
the risk of frostbite. Summers are short but relatively warm for the
latitude. This is partly due to the long hours of daylight (the sun
does not set at all for a short time each year at places within the
Arctic Circle, although its angle is always low in the sky) and
partly due to its continental location far from the influence of the
sea.
Precipitation is light throughout the year partly because the air is
too cold to hold much moisture and partly because most places
are a long way from any rain-bearing winds from the sea. It falls
as snow in winter and may be blown about in blizzards. The
summer maximum results from occasional convectional
rainstorms occurring when temperatures are at their highest. 47
a) Colorize the cold climates in Figure 13.2 like the master copy (overhead slide) and name
the main areas of cold climates
K
Cold climate
b) Read the following text, analyze the climate graph of
Fairbanks and localize Fairbanks in your Atlas and in
Figure 13.2
The cold climate is found to the pole ward side of 60°N in
Eurasia, where it extends from Scandinavia across Russia
to the Pacific, and across North America, central Alaska and
northern Canada (Figure 13.2). The graph for Fairbanks
shows the large annual range in temperature that typifies
this type of climate. Winters are very long, dark and
extremely cold. This is partly due to the northerly latitude
which, for places within the Arctic Circle, means a period of
time when the sun fails to rise above the horizon, and partly
due to the distance from any moderating influence of the
sea. Strong winds can lower temperatures, increase the
wind-chill factor and bring the risk of frost-bite.
Summers are short but relatively warm for the latitude. This is partly due to the long hours of daylight (the sun does not
set at all for a short time each year at places within the Arctic Circle, although its angle is always low in the sky) and
partly due to its continental location far from the influence of the sea. Precipitation is light throughout the year partly
because the air is too cold to hold much moisture and partly because most places are a long way from any rain-bearing
winds from the sea. It falls as snow in winter and may be blown about in blizzards. The summer maximum results from
occasional convectional rainstorms occurring when temperatures are at their highest.
a) Colorize the cold climates in Figure 13.2 like the master copy (overhead slide) and name
the main areas of cold climates
Cold climate
b) Read the following text, analyze the climate graph of
Fairbanks and localize Fairbanks in your Atlas and in
Figure 13.2
The cold climate is found to the pole ward side of 60°N in
Eurasia, where it extends from Scandinavia across Russia
to the Pacific, and across North America, central Alaska and
northern Canada (Figure 13.2). The graph for Fairbanks
shows the large annual range in temperature that typifies
this type of climate. Winters are very long, dark and
extremely cold. This is partly due to the northerly latitude
which, for places within the Arctic Circle, means a period of
time when the sun fails to rise above the horizon, and partly
due to the distance from any moderating influence of the
sea. Strong winds can lower temperatures, increase the
wind-chill factor and bring the risk of frost-bite.
Summers are short but relatively warm for the latitude. This is partly due to the long hours of daylight (the sun does not
set at all for a short time each year at places within the Arctic Circle, although its angle is always low in the sky) and
partly due to its continental location far from the influence of the sea. Precipitation is light throughout the year partly
because the air is too cold to hold much moisture and partly because most places are a long way from any rain-bearing
winds from the sea. It falls as snow in winter and may be blown about in blizzards. The summer maximum results from
occasional convectional rainstorms occurring when temperatures are at their highest.
48
Work in pairs and answer the following questions as a recapitulation:
K
a) Some climates are described in the last few lessons. Their locations are
shown in Figure 13.2. Match each of the six climates with the following
descriptions:
-hot, dry summers; warm, wet winters
-hot, very wet summers; very warm, dry winters
-long cold winters, short warm summers, little rain
-hot, wet and humid all year
-cool summers; mild winters; rain all year
-hot, wet summers, warm, dry winters
b) Make a copy of the table below.
-fill in the left-hand column by choosing three of the climate types
-complete the table by using information from the relevant climate graph and text.
c) For each of the three climate types which you selected in (b):
-name the part, or parts, of the world in which it is located.
-explain how it is affected by:
-latitude (angle of the sun)
-distance from the sea
-prevailing winds.
-give reasons for any seasonal differences in climate.
49
Vocabulary list: Excel
50
Test A
Name:…………………… Klasse: 1HW
1. Why do global temperatures increase towards the Equator?
Datum: 30.1.2006
2P
2. Why are prevailing winds from the sea:
x warmer in winter
x cooler in summer?
1P
3. Why can snow be found in some places on the Equator:
1P
4. Characterise the equatorial climate:
3P
5. Analyze the climate graph of Manaus
2P
6. Describe the south-west monsoon:
Punkte 1
Note
2
3
5
4
5
4
6
7
3
8
9
2
2P
10
11
1
51
Test A
Mit Antworten
Klasse: 1HW
Datum: 30.1.2006
1. Why do global temperatures increase towards the Equator?
The equatorial, tropical continental and monsoon climates are therefore much warmer than places nearer to the
poles. This is due to the curvature of the Earth and the angle of the sun. At the Equator the sun is always high in the
sky. When it is overhead it shines directly downwards, concentrating its heat into a small area which will become
very hot. In contrast, the sun is always low in the sky towards the poles. This means that its heat is spread over a
wide area, and so temperatures remain lower. Notice also that the lower the angle of the sun, the greater the amount
of atmosphere through which the rays have to pass. This means that more heat will be lost to gases, dust and cloud
in the atmosphere. This is why places in the south of Britain can expect to be warmer, especially in summer, than
places further north.
2. Why are prevailing winds from the sea:
x warmer in winter
x cooler in summer?
Prevailing winds: Prevailing winds will bring warm weather if they pass over warm surfaces (the
land in summer, the sea in winter) and cold weather if they blow across cold surfaces (the land in
winter, the sea in summer). As Britain´s prevailing winds are from the south-west, they are cool in
summer but warm (mild) in winter.
3. Why can snow be found in some places on the Equator:
Altitude: Temperatures decrease, on average, by 1°C for every 100 meters in height. As many parts of the Scottish
Highlands are over 1000 meters, they will be at least 10°C cooler than coastal places. In fact, the wind chill factor will
make them even colder, and enables snow to lie for long periods during winter.
4. Characterise the equatorial climate:
Equatorial areas have annual rainfall totals in excess of 2000 mm, mainly due to convectional thunderstorms which
occur during most afternoons throughout the year (Fig. 12.10). These storms are due to the convergence of warm air
(the trade winds). The warm air is forced to rise, creating an area of low pressure and giving heavy rain (Fig. 13.1) .
Some places, like Manaus, may have two or three drier, but not dry, months when the sun is overhead at the
opposite tropic (which is Cancer in the case of Manaus), and most rain when the sun is closer to being overhead.
Winds are generally light (the doldrums are areas of calm over equatorial oceans) and variable (there are no
prevailing winds, Figure 13.1). The equatorial climate is characterised by its high humidity, a lack of seasonal change,
and a daily weather pattern that remains remarkably uniform throughout the year.
5. Analyze the climate graph of Manaus:
Figure 13.3 is a climate graph for Manaus which is located 3° south of the Equator and in the centre of the Amazon
basin in Brazil. It shows that temperatures are both high and constant throughout the year. The small annual range of
2°C is due to the sun always being at a high angle in the sky, even if not always directly overhead (Fig. 12.2).
6. Describe the south-west monsoon:
The south-west monsoon (Figure 13.8) the sun appears to be overhead at the Tropic of Cancer in June. Places to
the north of the Himalayas, which are a long way from any moderating influence of the sea, become extremely
hot. As the hot air rises, an extensive area of low pressure is formed and warm, moist air is drawn northwards
from the Indian Ocean. Where the air is forced to rise over mountains (e.g. the Western Ghats and the
Himalayas), it gives large amounts of relief rainfall (Figure 12.8).
52
Test B
Name:…………………… Klasse: 1HW
Datum: 30.1.2006
1. Why do places in the centre of continents have warmer summers and colder
winters than places that have a coastal location?
2. How can ocean currents affect the temperatures of coastal areas?
3. Why can snow be found in some places on the Equator.
4. Characterise the daily pattern of the Equatorial Climates in some few short points:
5. Analyze the climate graph of Timbuktu:
sd
6. Describe the north- east monsoon:
Punkte 1
Note
2
3
5
4
5
4
6
7
3
8
9
2
10
11
1
53
Test B
Mit Antworten
Klasse: 1HW
Datum: 30.1.2006
1. Why do places in the centre of continents have warmer summers and colder
winters than places that have a coastal location?
Distance from the sea: The sea (a liquid) is less dense than the land (a solid) and can be heated to a greater depth.
This means that the sea takes much longer to heat up in summer than does the land. Once warmed, however, the sea
retains its heat for much longer, and cools down more slowly than the land in winter. This is why places that are inland
are warmer in summer but colder in winter than places on the coast. As Britain is surrounded by the sea, it tends to get
cool summers and mild winters. The largest reservoir of heat in winter is the Atlantic Ocean, even though it is still cold
enough to die from hypothermia within a few minutes should you fall into it. This explains why western parts of Britain
are warmer than places to the east in winter.
2. How can ocean currents affect the temperatures of coastal areas?
Ocean currents: Many coastal areas are affected by ocean currents. The North Atlantic Drift is a warm current of
water which originates in the Gulf of Mexico. It keeps the west coast of Britain much warmer in winter than other places
in similar latitudes
.
3. Why can snow be found in some places on the Equator.
Altitude: Temperatures decrease, on average, by 1°C for every 100 meters in height. As many parts of the Scottish
Highlands are over 1000 meters, they will be at least 10°C cooler than coastal places. In fact, the wind chill factor will
make them even colder, and enables snow to lie for long periods during winter.
4. Characterise the daily pattern of the Equatorial Climates in some few short points:
The daily pattern: One day is very much like another, with places receiving 12 hours of daylight and 12 hours of
darkness. The sun rises at 0600 hours and its heat soon evaporates the morning mist, the heavy overnight dew, and
any moisture remaining from the previous afternoon´s storm. Even by 0800 hours temperatures are as high as 25°C
and by noon, when the sun is near to a vertical position, they reach 33°C. The high temperatures cause air to rise in
powerful convection currents. The rising air, which is very moist due to rapid evapotranspiration from swamps, rivers
and the rainforest vegetation (Figure 13.4), Cools on reaching higher altitudes. When it cools to its dew point – the
temperature at which water vapour condenses back into water droplets –large cumulus clouds develop. By midafternoon these clouds have grown into black, towering cumulonimbus which produce torrential downpours,
accompanied by thunder and lightning. Such storms soon cease, leaving the air calm. By sunset, at about 1800 hours,
the clouds have already begun to break up. Nights are warm (23°C) and very humid. As one nineteenth-century
botanist wrote while exploring the Amazon area, ´Such conditions are similar throughout the year, seemingly one long
tropical day´.
5. Analyze the climate graph of Timbuktu: This climate is found in central parts of continents, away
from coasts, and mainly between latitudes 5° and 15° north and south of the Equator (Figure 13.2). This includes the
Brazilian Highlands and parts of Venezuela (South America), northern Australia, and a large semi-circle surrounding
the Congo basin (Africa). This last area includes Kenya which, although straddling the Equator, lies at an altitude too
high to share the main features of the equatorial climate. The main characteristic of the tropical continental climate, as
illustrated by the climate graph for Timbuktu in southern Mali (Figure 13.5), is alternate wet and dry seasons,
6.
Describe the north- east monsoon:
The north-east monsoon (Figure 13.9) During the northern winter, the overhead son moves southwards. Places to the
north of the Himalayas now become very cold and an extensive area of high pressure develops. Winds blow
outwards from the high pressure area but, because they originate in a dry area, they give only small amounts
54 of
rain as they cross India – Mumbai, for example, only receives 45 mm in seven months. By the end of the ´dry´
season, many places are at risk of drought.
World Climate
Presentation of the teaching
preparation
• The main topics I have prepared
• My teaching objectives
• My framework
• Methods and experiences
55
World Climate
1st Atmospheric circulation and world climates
-Connection between atmospheric circulation and world
climates. (Figure, text, explanation)
-Importrant causes of wind developing: High-pressure, lowpressure, earth rotation (Figure, text, explanation)
2nd Factors affecting global temperatures
-Latitude and distance from the sea
-Prevailing winds, Ocean currents and Altitude
3rd Equatorial and tropical continental climates
-Equatorial climates and the daily pattern
-Tropical continental climates (climate graphs, figures, Text)
4th The monsoon, mediterranean and cold climates
-The monsoon
-Mediterranean and Cold climate (climate graphs, atlas, text)
5th Recapitulation
-Answer questions in groups and produce a card-game
-Play the -question and answer- game.
56
My teaching objectives
• They should learn geographic contents
• They should learn the special terminology in English and in
. German
• They should practice their English nearby
My Framework
•
•
•
•
They are pupils from the HTL-Bregenz
The pupils are 15/16 years old, they are 9th graders
Sometimes they are vocational pupils, sometimes they are
pupils from the upper level
There are big groups of 33 pupils
57
Methods and experiences
• Short steps at the beginning:
At the beginning they have to read small texts. A vocabulary list
and figures help them to understand the contents easily.
They have to cross right answers, or to fill in suitable sentences.
To much subject matter: Four hours for the first topic
• Difficult contents are developed step by step: For example, the
trade winds are developed in four steps. The experiences were
very good: Five of 33 pupils were able to draw this ground plan
self-dependent
• Reading and spelling by explaining for example a figure. They
read the texts with their English teacher too (spelling).
• Recapitulation exercises in pairs
• They exercise the skills in English, which they have learned in
..German.
• They answer questions in groups, produce a card-game and
...play it.
58
1st Atmospheric circulation and world climates
K
Any pattern of climate types that you could identify is mainly due
to the circulation of air in the atmosphere. In order to understand
this circulation, you need to be aware of the following processes:
1 If air next to the ground is heated, it expands, gets lighter an
rises.
Height of the air column
Height of the air column
after heating
before heating
Tallness of the air
mm
Tallness of the air
mmm
Fill in the
underlined, and
the framed texts
into the suitable
boxes
0° (Equator)
Mark the right answer with a cross
Attend: The weight oft the air column above the ground is
0 the same as
0 more than
59
0 less than before the heating
K
3 Wind, which is air in motion, blows from areas of high
pressure (H) to areas of low pressure (L). Therefore, the wind
in the atmosphere above 8 km blows from
0 the higher latitudes (30°N, 30°S) to the Equator
0 the Equator to the higher latitudes (30°N, 30°S)
12
km
L
H
30° N
H
L
0° (equator)
L
8
H
30° S
When this process is started, the air column at 30°N and 30°S
becomes 0 higher 0 lower and the air column at the equator
becomes 0 higher 0 lower, so that the atmospheric pressure at
the earth´s surface in 30°N and 30°S will 0 increase 0 decrease
as opposed to the atmospheric pressure at the earth´s surface at
the equator which will 0 increase 0 decrease.
Fill the Letter L (low pressure) or H (high pressure) into the
suitable box at the earth’s surface and complete the direction
60 of
the wind flow with red arrows.
K
12
km
L
H
H
L
L
8
H
30° N
30° S
0° (Equator)
This circulation was discovered by Mr. Hadley, so it´s called
Hadley cell
4 The Coriolis force prevents air from moving directly from areas
of high pressure to areas of low pressure – otherwise the
prevailing wind in the Atlantic Ocean between the Equator and
30° north would be from the north, not the north east, so-called
the north-easterly trades.
Draw the ground plan of the surface winds
61
12
km
L
H
H
L
L
8
H
30° N
30° S
0° (Equator)
This circulation was discovered by Mr. Hadley, so it´s called
Hadley cell
4 The Coriolis force prevents air from moving directly from areas
of high pressure to areas of low pressure – otherwise the
prevailing wind in the Atlantic Ocean between the Equator and
30° north would be from the north, not the north east, so-called
the north-easterly trades.
62
Read the following description and show the cycles at the basic of
Figure13.1 and 12.10 as well as in your Atlas at page……
Verbal description to Figure 13.1
The circulation is controlled by the build-up of heat at the
Equator, which causes air to rise (convection currents) and low
pressure to form. As the rising air cools, it condenses to give
thunderstorms before spreading outwards from the Equator.
As the air becomes denser (at 30°N and 30°S), it descends to
form a high pressure belt and, as it gets warmer and drier, an
area of desert. Some of the descending air, on reaching the
ground, returns to the Equator as the trade winds. The remainder
moves away from the tropics (the westerlies) towards places like
Britain where, as warm, moist tropical air, it meets with colder
polar air and is forced to rise, creating low pressure and
depressions (… it will be done later).
This explanation is an oversimplified one (if it was not, then
weather forecasting would be quite easy!). Due to the Earth´s tilt
and rotation, the position of the overhead sun appears to change,
giving us our seasons. The northern hemisphere is hottest when
the sun appears to be above the Tropic of Cancer (21 June). At
this time, the pressure and wind belts move northwards. In
contrast, the southern hemisphere is hottest when the sun
appears to be over the Tropic of Capricorn (21 December), by
which time the pressure and wind belts have moved south. The
resultant changes in pressure and wind are responsible for the
seasonal contrasts in climates, such as the tropical continental
63
and the Mediterranean climate types.
Work in pairs and answer the following questions as a recapitulation:
K
a) Why is pressure:
- low at the Equator ?
- high about 30° from the Equator ?
- low at about 60° from the Equator ?
b) What is reponsible for this:
- the trade winds in the tropics
- the prevailing south-westerlies in Britain
- convectional rainfall on the Equator
c) - Draw a simple diagram to show the general circulation of the atmosphere. Your
diagram should show the three circulation cells.
- What relationship can you see between the circulation of the atmosphere and the
pattern of world climate types?
Work in pairs and answer the following questions as a recapitulation:
a) Why is pressure:
-low at the Equator
-high about 30° from the Equator
-low at about 60° from the Equator
b) How does this pattern of high and low pressure account for:
-the trade winds in the tropics
-the prevailing south-westerlies in Britain
-convectional rainfall on the Equator
c) - Draw a simple diagram to show the general circulation of the atmosphere. Your
diagram should show the three circulation cells.
- What relationship can you see between the circulation of the atmosphere and the
pattern of world climate types?
64
3rd Equatorial and tropical continental climates
Equatorial
Places with an equatorial climate lie within 5° either side of the
Equator. The main areas are the large drainage basins of the
Amazon (South America) and Congo (Africa) rivers and the
extreme south-east of Asia (Fig. 13.2).
a) Colorize the Equatorial climates in Figure 13.2 like the
master copy (overhead slide) and name the main areas of
Equatorial climates
b) Read the following text, analyze the climate graph of
Manaus and loklisize Manaus in your Atlas and in Figure
13.2
Manaus (Brazil) 3°S; Altitude 44 m
Figure 13.3 is a climate
graph for Manaus which
is located 3° south of the
Equator and in the centre
of the Amazon basin in
Brazil. It shows that
temperatures are both
high and constant
throughout the year. The
small annual range of
2°C is due to the sun
always being at a high
angle in the sky, even if
not always directly
overhead (Fig. 12.2).
Annual range of temperature 2°C
Annual precipitation 2104 mm
65
66
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