Many scientists think that human activities are causing climate change. The table shows the carbon dioxide concentration in the atmosphere and the global mean temperature difference for some years. The temperature difference is compared with the mean temperature from 1951 to 1980.
| Year | Carbon dioxide concentration / ppm | Temperature difference / °C |
|---|---|---|
| 1880 | 291 | −0.17 |
| 1920 | 303 | −0.27 |
| 1960 | 317 | −0.03 |
| 2000 | 370 | +0.39 |
| 2020 | 414 | +1.01 |
Describe the relationship between carbon dioxide concentration and temperature difference shown by the data.
Explain why these data alone do not prove that increasing carbon dioxide causes the temperature to increase.
Carbon dioxide values before 1958 come from air trapped in ice cores. Early temperature values come from thermometer records.
Suggest two reasons why the values for 1880 and 1920 are less certain than the values for 2000 and 2020.
Methane is also a greenhouse gas. Give one human activity that releases methane.
Give two potential effects on the climate of increasing global temperatures.
97 exam-style questions on Edexcel GCSE Chemistry 9.2 Earth and atmospheric science, covering 9.2.1 The Earth's early atmosphere, 9.2.2 How the atmosphere evolved, 9.2.3 Chemical test for oxygen, and 9.2.4 The greenhouse effect and climate change. Each one has a worked solution and a mark scheme showing where the marks go.