Final answer:
Greenhouse gases like water vapor and carbon dioxide trap heat from the sun, creating a natural greenhouse effect that stabilizes the Earth's temperature. Without these gases, the average temperature would be much colder. However, human activities have increased greenhouse gas concentrations, leading to global warming and climate change.
Step-by-step explanation:
The greenhouse effect is a natural process that allows certain gases in the Earth's atmosphere, such as water vapor and carbon dioxide, to trap heat from the sun and keep the Earth's temperature stable. When sunlight reaches the Earth's surface, it is absorbed and re-emitted as infrared radiation. However, greenhouse gases absorb and re-emit a significant portion of this radiation, preventing it from escaping back into space. This process, known as the greenhouse effect, helps regulate and stabilize the Earth's temperature at levels suitable for life.
Greenhouse gases, including water vapor, carbon dioxide, methane, nitrous oxide, and ozone, act like a blanket around the Earth, trapping heat and warming the planet. Without these gases, the energy radiated onto the Earth's surface would be mostly lost into space, leading to much lower temperatures. In fact, if there were no greenhouse gases, the average temperature of the Earth would be approximately -18°C.
Human activities, such as burning fossil fuels and deforestation, have increased the concentration of greenhouse gases in the atmosphere. This enhanced greenhouse effect is causing global warming and climate change, leading to significant impacts on the Earth's ecosystems and weather patterns.