Which gas is a major contributor to the enhanced greenhouse effect due to human activities?

Which gas is a major contributor to the enhanced greenhouse effect due to human activities?

• A. Oxygen (O2)
• B. Nitrogen (N2)
• C. Hydrogen (H2)
• D. Carbon dioxide (CO2)

Answer: (D)

The main idea is how human activities raise the level of greenhouse gases that trap heat in Earth’s atmosphere. Carbon dioxide is the primary contributor because it efficiently absorbs infrared radiation emitted by the surface and stays in the atmosphere for a very long time, accumulating from burning fossil fuels, cement production, and land-use changes. Even though some other gases can be more potent per molecule, their overall impact is smaller because they are present in much lower amounts or have shorter lifetimes. Oxygen and nitrogen don’t act as strong greenhouse gases under ordinary conditions; their diatomic molecules don’t absorb infrared radiation well in the relevant wavelengths, so they don’t significantly warm the planet. Hydrogen is not a major contributor in the current atmosphere for similar reasons and because it’s not released in the quantities that would make it a dominant greenhouse gas. So, carbon dioxide stands out as the major driver of the enhanced greenhouse effect due to human activities.

The main idea is how human activities raise the level of greenhouse gases that trap heat in Earth’s atmosphere. Carbon dioxide is the primary contributor because it efficiently absorbs infrared radiation emitted by the surface and stays in the atmosphere for a very long time, accumulating from burning fossil fuels, cement production, and land-use changes. Even though some other gases can be more potent per molecule, their overall impact is smaller because they are present in much lower amounts or have shorter lifetimes.

Oxygen and nitrogen don’t act as strong greenhouse gases under ordinary conditions; their diatomic molecules don’t absorb infrared radiation well in the relevant wavelengths, so they don’t significantly warm the planet. Hydrogen is not a major contributor in the current atmosphere for similar reasons and because it’s not released in the quantities that would make it a dominant greenhouse gas.

So, carbon dioxide stands out as the major driver of the enhanced greenhouse effect due to human activities.