India’s CO2 emissions from burning fossil fuels are expected to rise by 4.6% in 2024, the highest increase among major economies, according to the Global Carbon Project. Globally, fossil-based CO2 emissions are projected to reach a record 37.4 billion tonnes in 2024, marking a 0.8% rise from 2023. If this trend continues, there is a 50% chance of global warming exceeding 1.5°C within six years.
The Role of CO2 in Climate Change
CO2 is the primary driver of anthropogenic climate change. It is one of the most critical greenhouse gases (GHGs) that trap heat in the Earth’s atmosphere, contributing significantly to the greenhouse effect.
Understanding the Greenhouse Effect
- Greenhouse Gases (GHGs): GHGs, including CO2 and methane (CH4), trap heat by absorbing infrared radiation.
- How It Works:
- The Sun emits shortwave radiation absorbed by the Earth’s surface.
- This energy is re-emitted as infrared radiation (heat).
- GHGs trap this heat, preventing it from escaping into space, thus warming the planet.
Why CO2 is More Significant Than Other GHGs
- High Concentration:
- CO2 is more abundant than other GHGs. Since the Industrial Revolution, atmospheric CO2 levels have increased by 50%, reaching 150% of their 1750 levels.
- Long Atmospheric Lifespan:
- CO2 persists in the atmosphere for centuries.
- CH4 stays for about 10 years, converting into CO2.
- Nitrous Oxide (N2O) lasts around 100 years.
- CO2:
- 40% remains for 100 years.
- 20% for 1,000 years.
- 10% can linger for 10,000 years.
CO2 vs. Other GHGs
While CH4 and Hydrofluorocarbons (HFCs) are more potent than CO2, their overall warming effect is less due to their lower concentrations and shorter atmospheric lifespans.
- CH4 is 80 times more powerful than CO2 over 20 years.
- HFCs can be thousands of times more powerful, but CO2 still contributes 70% of global warming.
Water Vapour: A Unique GHG
Water vapour, the most abundant GHG, has a short atmospheric cycle (10 days). It amplifies warming as higher temperatures increase evaporation, but its impact is secondary to CO2.
Multiple-Choice Questions (MCQs):
1. What is the expected increase in India’s CO2 emissions in 2024?
- A) 2.5%
- B) 3.6%
- C) 4.6%
- D) 5.6%
- Answer: C) 4.6%
2. What is the projected global CO2 emission level for 2024?
- A) 35 billion tonnes
- B) 36 billion tonnes
- C) 37.4 billion tonnes
- D) 38.4 billion tonnes
- Answer: C) 37.4 billion tonnes
3. Which GHG contributes the most to global warming?
- A) Methane (CH4)
- B) Carbon Dioxide (CO2)
- C) Hydrofluorocarbons (HFCs)
- D) Nitrous Oxide (N2O)
- Answer: B) Carbon Dioxide (CO2)
4. How long does CH4 typically stay in the atmosphere before converting into CO2?
- A) 5 years
- B) 10 years
- C) 50 years
- D) 100 years
- Answer: B) 10 years
5. What percentage of a CO2 pulse remains in the atmosphere after 1,000 years?
- A) 10%
- B) 20%
- C) 30%
- D) 40%
- Answer: B) 20%