Final answer:
a. Greenhouse gases allow solar energy in but trap heat energy, acting like a greenhouse's glass panels and contributing to the greenhouse effect which is essential for maintaining life-sustaining temperatures on Earth.
Step-by-step explanation:
As a group, the greenhouse gases allow solar energy to pass through Earth's atmosphere but absorb heat energy as energy passes back through the atmosphere into outer space. Greenhouse gases, such as carbon dioxide, methane, water vapor, nitrous oxide, and ozone, act like the glass panels of a greenhouse. They permit short-wave radiation from the sun to enter but impede the escape of long-wave thermal (infrared) radiation back into space.
The warming effect of greenhouse gases is critical for maintaining temperatures that allow for life on Earth. However, human activities, particularly since the Industrial Revolution, have increased concentrations of these gases in the atmosphere, leading to a more significant greenhouse effect and contributing to global climate change.