Question

0-9. GREENHOUSE EFFECT
CO2 passes short wave length light (visible) but blocks long wave length
radiation (IR). Explain how adding CO2 to an atmosphere increases the
surface temperature of a planet. Consider the temperature of the sources
of radiation in and out.

Answer 1

CO₂ which passes short wavelength light but blocks long wavelength radiation.

Explain how adding CO₂ to an atmosphere which increases the surface temperature of a planet.

A tiny amount of CO₂ and other greenhouse gases, like methane and water vapour that keep the Earth’s surface 30 ⁰C warmer. We have added 42% more CO₂ but that doesn't mean the temperature will go up by 42% too. Doubling the amount of CO₂ which does not double the greenhouse effect.

As the amount of CO₂ goes up, temperatures do not rise at the same rate. Carbon dioxide is no dark-horse candidate for the warming of an atmosphere. Sunlight enters the atmosphere as ultraviolet and visible light. Some of this solar energy is then radiated back toward space as infrared energy or heat. The atmosphere is 78% nitrogen and 21% oxygen which are both gases made up of molecules which containing two atoms. But the greenhouse gases, including carbon dioxide, water vapor and methane, each have at least three atoms in their molecules.

When the molecules in carbon dioxide and other greenhouse gases which re-emit this long-wave radiation back toward Earth's surface, then the result is "warming". Thus, the presence of carbon dioxode in our atmosphere allows sunshine to penetrate to the surface but inhibits the emission of infrared radiation to space.