Scientists measure carbon dioxide trapped in bubbles in ancient ice.
| Time | Carbon dioxide concentration (ppm) |
|---|---|
| Natural cycles over 800 000 years before 1750 | varied between 180 and 300 |
| 1750 | 280 |
| 2023 | 420 |
Which statement is supported by the data?
The concentration in 2023 was about 33% higher than in 1750 and above the natural range.
The concentration in 2023 was within the natural range, so the rise since 1750 is natural.
The concentration in 2023 was 50% higher than in 1750 and above the natural range.
Natural cycles changed the concentration by more than the rise between 1750 and 2023.
51 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.