MCQ Detailed View

The greenhouse effect is a natural phenomenon that keeps the Earth warm enough to support life. However, when certain gases increase excessively in the atmosphere, this effect becomes stronger, leading to global warming and climate change. The main gas responsible for this problem is carbon dioxide (CO₂).

Carbon dioxide is a greenhouse gas, meaning it traps heat energy from the Sun. Normally, sunlight passes through the atmosphere and warms the Earth's surface. The Earth then emits heat back toward space in the form of infrared radiation. Greenhouse gases like CO₂ absorb some of this heat and re-radiate it back to the Earth's surface, keeping the planet warm. This is beneficial in normal amounts, but excessive CO₂, mainly due to burning fossil fuels (coal, oil, gas), deforestation, and industrial emissions, traps too much heat, causing the greenhouse effect to intensify.

Other gases, such as methane (CH₄) and nitrous oxide (N₂O), also contribute, but CO₂ is the largest and most impactful contributor due to its high volume in the atmosphere. Carbon monoxide (option 2) is a harmful gas for human health but does not significantly trap heat. Carbon tetrachloride (option 3) is a chemical used in industrial applications and ozone-depleting substances but is not the main cause of the greenhouse effect.

The buildup of CO₂ leads to rising global temperatures, melting glaciers, rising sea levels, heatwaves, and changing weather patterns worldwide. Reducing CO₂ emissions by shifting to renewable energy, planting trees, and improving energy efficiency are major solutions to slow down the greenhouse effect.

Hence, the correct answer is Option 1: Carbon dioxide, as its excess concentration is the primary driver of the enhanced greenhouse effect on Earth.