Question

21 multiple choice 1 point why do we need greenhouse gases on earth? we need them because they block our atmosphere from escaping into space we dont want them because they cause climate change we need them because they keep the planet warm

Explanation:

Greenhouse gases, such as carbon dioxide and methane, play a crucial role in Earth's climate system. They trap heat (infrared radiation) emitted from the Earth's surface, preventing it from escaping directly into space. This natural greenhouse effect is essential for maintaining a temperature range on Earth that is suitable for life. Without greenhouse gases, the average temperature of the Earth would be much colder (approximately -18°C instead of the current average of about 15°C).

Option 1 is incorrect because greenhouse gases do not block the atmosphere from escaping into space. The Earth's gravity is the main factor that keeps the atmosphere from escaping. Option 2 is also incorrect because while excessive amounts of greenhouse gases (due to human activities like burning fossil fuels) can cause climate change (global warming), in appropriate amounts, they are necessary. Option 3 is correct as it accurately reflects the role of greenhouse gases in keeping the planet warm through the natural greenhouse effect.

Answer:

C. We need them because they keep the planet warm