Question 1: Define the greenhouse effect in your own words.

Answer: The greenhouse effect is the process by which certain gases in the Earth's atmosphere trap heat from the Sun, warming the planet.

Question 2: Name three major greenhouse gases responsible for climate change.

Answer: Carbon dioxide (CO₂), methane (CH₄), nitrous oxide (N₂O).

Question 3: Explain how increased levels of greenhouse gases lead to global warming.

Answer: Higher concentrations of greenhouse gases trap more infrared radiation emitted by Earth's surface, reducing heat escape into space and causing an overall increase in global temperatures.

Question 1: Calculate the increase in temperature (in °C) if the concentration of CO₂ doubles, assuming a direct proportionality with radiative forcing. Use the formula: ΔT = λ × ΔF, where λ = 0.8 °C per W/m² and ΔF = 5.35 × ln(C/C₀). Given initial concentration C₀ = 280 ppm and new concentration C = 560 ppm.

Answer: Approximately 1.2°C

Question 2: The current atmospheric concentration of methane (CH₄) is about 1.9 ppm. If it increases to 3.8 ppm, calculate the change in radiative forcing using ΔF = 0.036 × (√C - √C₀). Show your working.

Answer: Approximately 0.05 W/m²

Question 1: Describe a simple experiment to measure the effect of increased CO₂ levels on plant growth, including variables to control and safety precautions.

Answer: An experiment could involve growing identical plants in controlled environments with different CO₂ concentrations, controlling variables such as light, temperature, and water. Safety precautions include handling CO₂ cylinders carefully, ensuring proper ventilation, and avoiding inhalation of high concentrations.

Question 1: A report states that over the past 50 years, atmospheric CO₂ levels have increased from 320 ppm to 410 ppm. Explain how this increase correlates with global temperature rise and climate change impacts.

Answer: The increase in CO₂ levels enhances the greenhouse effect, trapping more heat and leading to rising global temperatures. This correlates with observed climate change impacts such as melting ice caps, sea level rise, and more extreme weather events.

Question 1: Explain the role of methane in climate change, including its global warming potential compared to CO₂. (6 marks)

Answer: Methane is a potent greenhouse gas with a higher global warming potential than CO₂—approximately 25 times greater over a 100-year period. It traps more infrared radiation per molecule, contributing significantly to climate change despite its lower concentration. Its increase accelerates global warming and impacts atmospheric chemistry.

Question 1: Describe how carbon capture and storage (CCS) technology can help reduce greenhouse gas emissions from industrial sources.

Answer: CCS involves capturing CO₂ emissions from industrial processes or power plants and transporting it to underground storage sites, preventing it from entering the atmosphere and thus reducing the greenhouse effect.