Global warming

We are learning how to:

• explain climate change in terms of human activity

• consider the possible effects of global warming.

Global warming

The average surface temperature of the Earth has increased by about 0.8 °C over the last 100 years. Much of this increase has occurred in the last 30 years. This suggests that the trend in rising temperature is increasing.

This may not sound like much of an increase, but even this small rise has caused major changes to the climate in different parts of the world. This is known as global warming

The average winter temperature at the North Pole is around −34 °C while in the summer the average is around 0 °C. Scientists who study the North Pole have been aware for some time that average temperatures are increasing. The northern polar ice cap is slowly getting smaller and the ice is getting thinner as more ice turns to water

In some parts of the world the summers are getting much hotter and drier. Warmer weather has led to water shortages and droughts in certain parts of the world.

Water is being used up more quickly than it can be replaced by nature.

In areas of the world where there are large forests, the vegetation is much drier than in the past due to higher temperatures and lack of rain.

Activity 8.2.1

The effects of drought

You should work in a small group for this activity. Here is what you should do:

1. Discuss what effects a drought is likely to have on people and on wildlife.

2. Imagine there is a drought in your area now. Discuss what steps you could take to reduce the use of water

Check your understanding

1. Copy and complete the following sentences by writing either ‘increasing’ or ‘decreasing’.

a) The surface temperature of the Earth has been over the last 100 years.

b) The thickness of the ice at the North Pole is c) In some parts of the world summers are getting hotter and drier. The effects of this are that: i) water levels in lakes and reservoirs are . ii) the risk of forest fires is . iii) the number of wild animals and farm animals dying from lack of food and water is .

Fun fact

There is land beneath the ice at the South Pole, but the North Pole consists entirely of ice. If the northern polar ice cap were to completely melt it would be possible to sail over the North Pole.

Key terms

global warming rise in average surface temperature of the Earth droughts lack of rain