Climate

Factors that influence climate.

1. Latitude2. Distance from sea / ocean3. Prevailing winds and air masses

LatitudeLatitude 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 heats up and cools down more slowly than land.Winter = water colder than landSummer = water warmer than land

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.

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 Temperate Cold

Equatorial Cool Temperate BorealSavanna Warm Temperate TundraHot Desert

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.