Climate
Introduction




Factors that influence climate.
1. Latitude
2. Distance from sea / ocean
3. Prevailing winds and air masses
Latitude


Latitude is the distance north or south of the equator.
In general, the further north or south of the equator an
area is, the colder it will be.
Distance from the sea / ocean.




Water in the sea absorbs heat very slowly during the
summer.
It also loses its heat very slowly during the winter.
Therefore, areas of land close to the sea will be cooled
by the water in the summer, and warmed up by the
water in the winter.
Therefore, areas close to the sea tend to have a small
temperature range.
Distance from the sea / ocean.



Land absorbs heat very quickly during the summer, and
loses it very quickly during the winter.
Therefore, inland areas far from the sea tend to have
very hot summers and very cold winters.
Therefore, inland areas far from the sea tend to have a
larger temperature range than coastal areas. (Areas
beside the sea).
Distance from the sea / ocean.
Prevailing Winds and Air Masses


Winds and air masses can make an area colder, warmer,
wetter or drier.
Their influence will depend on the direction they come
from and whether they pass over land or water.
Prevailing Winds and Air Masses
Factors that influence local climate



Local climate is the climate experienced by a
small region, for example, the Wicklow
Mountains.
Even though Wicklow is in Ireland, the area of
the Wicklow mountains would generally be
colder and wetter than low lying Co. Kildare.
Local climates are influenced by the shape of the
land, in particular, Aspect and Altitude.
Aspect

Aspect refers to the direction in which a slope is facing.
For example, a slope can be facing north or south.

In the northern hemisphere, where we live, south facing
slopes are warmer. Why?

There are 3 reasons why.



The sun shines directly onto south facing slopes.
Warm southerly winds blow against south facing slopes.
They are protected from the cold northerly winds.
Aspect
Altitude

Altitude refers to height above sea level.

In general, the higher you go, the colder it is.

The temperature drops 7°C for each 1000m you go up.
Why?

There are two reasons for this.


This is because the air is thinner and it can hold less
heat.
Upland areas are more exposed to the wind which also
makes it colder. This is known as the Wind Chill Factor.
Altitude
Case Study: Mount Kilimanjaro: Even though this mountain is in
Africa, and very close to the equator, it is so high that the top part of
the mountain is covered in snow all year round. The word Kilimanjaro
means White Mountain, just like Mont Blanc in the Alps.
Where is Mount Kilimanjaro?
= Mt. Kilimanjaro
= The Equator
Mount Kilimanjaro
Mount Kilimanjaro




Mt. Kilimanjaro is made from 3
inactive volcanoes.
It is in north-eastern Tanzania,
340 km south of the Equator
close to the border with Kenya.
It is the highest mountain in
Africa at 5,895 metres.
Mount Kilimanjaro is one of the
tallest freestanding mountains
in the world, rising 4600 m
from the base.
World Climates





There are many different climate types in the
world.
World climates can be put into 3 groups.
1. Hot Climates
2. Temperate Climates
3. Cold Climates
The Major Climates of the World
The Major Climates of the World
Hot
Equatorial
Savanna
Hot Desert
Temperate
Cold
Cool Temperate
Warm Temperate
Boreal
Tundra
Hot Climates of the World

Most hot climates are found within
latitudes 30°N and 30°S. In other words,
they are found close to the equator.
Hot Climates of the World
Hot Climates






Equatorial Climate
Hot all year (28°C)
One Season
Rain every afternoon.
Rainfall 2000mm / yr
Rainforest / jungle.





Savanna Climate
Hot all year (25-35°C)
Two seasons
Wet summers, dry
winters
Scattered trees /
grassland
Hot Climates

Desert Climate

Temperature: Day – 30-50°C



Night 5°C
Precipitation:
There is very little rain (100mm per year).
There are long droughts (no rain) followed by sudden
downpours.
Desert Climate: Temperature + Precipitation
Questions






What is the temperature in December?
What is the temperature in August?
How many millimetres of rain fell in January?
How many millimetres of rain fell in July?
What is the average monthly rainfall from October to
March, and from April to September?
Calculate the temperature range.
Plants and Animals in the Desert.



It is difficult for plants and animals to survive in the
desert because there is so little water.
Plants that survive have adapted to the desert climate.
One example is the Cactus.
It has thick bark which prevents loss of moisture and it
can store water inside it. The spread out over long
distance to reach available water. The needles protect it
from wild animals.
Animals in the Desert


An example of an animal that has adapted to life
in the desert is the camel.
They have long eye lashes to protect their eyes
and thick skin on their legs so they can kneel in
the hot sand. They have wide hooves for
walking in the sand and can store fat in their
humps for when food is scarce.
Temperate Climates of the World
Cool Temperate Oceanic Climate




Warm summers 15-17°C
Mild winters 4-6°C.
Rain throughout the year, most in winter.
Weather is cloudy and changes often
Warm Temperate Oceanic
Warm Temperate Oceanic Climate



This is also known as a Mediterranean
climate because many countries around
the Mediterranean Sea experience this
type of climate.
Summers are hot and dry, 30°C.
Winters are mild and moist, 4-6°C, with
400 – 700mm of rain.
Warm Temperate Oceanic
Questions










What is the temperature in December?
What is the temperature in March?
What is the temperature in July?
How much rain fell in May?
How much rain fell in November?
Calculate the total amount of rainfall throughout the
entire year.
Calculate the average rainfall from April to September,
and from October to March.
Contrast the amount of rainfall during these two periods.
Calculate the average temperature for Dec, Jan, Feb,
and Jun, Jul, Aug.
What is the temperature range?
Cold Climates of the World
Boreal Climate




Summers are short, long days, 10-15°C
Winters are very cold, long nights, -25 °C
Low precipitation 400mm / year.
Natural Vegetation is the Taiga –
Evergreen coniferous forest.
Tundra Climate






Summers are short and cool, rarely above 15°C.
Winters are long and cold, as low as -35°C
Large temperature range.
Precipitation (snow) less than 250mm / year.
Little vegetation because of extreme cold.
Animals and birds during the summer but not winter.
Taiga Forest
Boreal Climate
Questions










What is the temperature in August?
What is the temperature in January?
How much rain fell in March?
How much rain fell in July?
What was the average amount of rainfall from May to October?
What was the average amount of rainfall from November to
April?
What was the average temperature from May to October?
What was the average temperature from November to April?
Calculate the mean temperature for the year.
Calculate the temperature range.
Revision Questions













1. List 3 factors that can influence world climates.
2. Explain how each factor can influence world climates.
3. List 2 factors that can influence local climates.
4. Explain in detail how each factor can influence local climates. (D)
5. List the 3 different groups of climate on earth.
6. Make 3 lists showing all the climates in each group.
7. List 3 countries with hot climates.
8. Using the headings temperature, rainfall, vegetation/animals write a
detailed summary of two hot climates.
9. Select one plant and one animal and explain how they have adapted to
live in a hot climate.
10. List 3 countries with temperate climates.
11. Using the headings temperature, rainfall, write a detailed summary of
two temperate climates.
12. List three countries with cold climates.
13. Select one plant / animal and explain how they have adapted to live in
a cold climate.
Sample Answers

Section 2, Q.2.
Altitude means height above sea level. It affects climate in
the following way. The higher above sea level you go,
the colder it gets. The temperature drops 7°C for every
1000m you go up. There are two reasons for this.
a). The air is thinner and can hold less heat.
b). You are more exposed to the wind. This is called the
wind chill factor.
Sample Answers

Section 2, Q.3
Aspect refers to the direction in which a slope is facing. It affects climate in the
following way. In the northern hemisphere south facing slopes are warmer
than north facing slopes. There are 3 reasons for this.
a). South facing slopes receive direct sunlight.
b). They receive warm winds coming from the south.
c). They are protected from cold winds coming from the north.
The opposite is true for North facing slopes and so they are colder.