A climate model predicts atmospheric concentrations under one future emissions scenario.
| Gas | Concentration at the start of the model period (parts per billion) | Concentration at the end of the model period (parts per billion) | Warming effect of one molecule compared with one molecule of carbon dioxide |
|---|---|---|---|
| Carbon dioxide | 420 000 | 450 000 | 1 |
| Methane | 1 900 | 3 300 | 25 |
Calculate which gas is predicted to contribute more to the additional warming during the model period. Show your working.
The model assumes that cattle numbers continue to increase. Explain how reducing cattle numbers could change the warming predicted by the model.
109 exam-style questions on OCR GCSE Chemistry 6.3 Interpreting and interacting with earth systems, covering 6.3.1 Formation and evolution of the atmosphere, 6.3.2 The greenhouse effect and climate change, 6.3.3 Sources and problems of atmospheric pollutants, and 6.3.4 Producing potable water. Each one has a worked solution and a mark scheme showing where the marks go.