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).
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.
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.
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.
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 • 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 Hot TemperateCold Equatorial Cool Temperate Boreal Savanna Warm Temperate Tundra Hot 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.
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
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.
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.
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 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.
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?
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.
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.