What is climate change?
Climate change is the change in weather patterns that we can see on earth over a long time e.g. hundreds to millions of years. Climate can change naturally because of changes in:
- volcanic eruptions
- ocean currents
- the sun
How is weather different from climate?
Changes caused by people
People have caused recent changes in climate by burning oil, gas and coal and by removing forest and farming. This has caused the levels of greenhouse gases in the air to grow. Greenhouse gases cause global warming by stopping heat from escaping back into space.
How are greenhouse gases measured?
What are greenhouse gases?
Greenhouse gases are those that help cause the ‘greenhouse effect’. The most common greenhouse gases are:
- water vapour (water in its gas form)
- carbon dioxide
- methane
What is the ‘greenhouse effect’?
The ‘greenhouse effect’ is what happens when the sun’s heat is trapped by greenhouse gases (in the way sun is trapped by glass in a glass house). This causes higher temperatures on Earth. One of the greenhouse gases, carbon dioxide, has increased very quickly since the beginning of the industrial revolution in 1750. This is when people started burning more fossil fuels (such as coal and oil). This increase in carbon dioxide can be seen on the graph below:
