IBDP Physics- B.2 Greenhouse effect - IB Style Questions For HL Paper 1A -FA 2025
▶️ Answer/Explanation
The enhanced greenhouse effect refers to the additional warming caused by human activities that increase greenhouse gas concentrations in the atmosphere.
– (A) is a consequence, not a cause
– (B) is natural and not the primary human cause
– (C) contributes but is secondary
– (D) Burning fossil fuels is the primary source of anthropogenic CO₂ emissions, the main driver of the enhanced greenhouse effect
✅ Answer: (D)
▶️ Answer/Explanation
Volcanic activity can release greenhouse gases such as carbon dioxide into the atmosphere. These gases increase the greenhouse effect and can raise global temperatures.
Deforestation reduces the number of trees available to absorb carbon dioxide through photosynthesis. In addition, carbon stored in trees is released into the atmosphere when forests are cleared, increasing greenhouse gas concentration.
Increased solubility of carbon dioxide in the ocean would remove more \( \mathrm{CO}_2 \) from the atmosphere, which would reduce, not increase, the rate of global warming.
Therefore, only factors I and III increase the rate of global warming.
✅ Answer: (B)
▶️ Answer/Explanation
I. Capturing and storing \( \mathrm{CO}_2 \) reduces the amount released into the atmosphere. Since \( \mathrm{CO}_2 \) is a major greenhouse gas, this reduces the enhanced greenhouse effect.
II. Nuclear power using uranium-235 does not produce \( \mathrm{CO}_2 \) during electricity generation. Replacing natural gas with nuclear power therefore reduces greenhouse gas emissions.
III. Burning oil releases more \( \mathrm{CO}_2 \) per unit energy than natural gas. Switching from natural gas to oil would increase greenhouse gas emissions, not reduce them.
Therefore, only changes I and II reduce the enhanced greenhouse effect.
✅ Answer: (A)