Question

Earth's atmosphere helps to regulate its temperature. However, the addition of gases such as [missing gas] causes more energy to [missing word] radiate back toward Earth. As a result, the atmospheric temperature increases over time. If Earth had no atmosphere, it would radiate nearly as much energy as it receives from the Sun. This implies that the temperatures on Earth would be [missing word] Earth's current temperature.

a) Lower than

b) Higher than

c) Equal to

d) Unpredictable compared to

Answer 1

The Earth's atmosphere, due to greenhouse gases like CO₂, keeps the planet warmer than it would be without an atmosphere, leading to a surface temperature much higher than it would otherwise be.

Step-by-step explanation:

The Earth's atmosphere contains gases such as carbon dioxide (CO₂), methane (CH₄), and nitrous oxide (N₂O) that trap the Sun's energy, particularly the long-wave infrared radiation emitted by the warmed planet. This trapping of energy is known as the greenhouse effect, which maintains the Earth's surface temperature about 40°C higher than it would be without these gases. Without the greenhouse effect, the Earth's average temperature would be close to -18°C instead of the current 15°C, primarily because energy from the Sun would be radiated back into space without being trapped by these gases.

Therefore, to complete the student's statement, the [missing gas] could be 'carbon dioxide (CO₂)', the [missing word] after 'causes more energy to' could be 'be trapped and', and the temperatures on Earth would be a) Lower than Earth's current temperature if it had no atmosphere.