How Does Earth’s Atmosphere Support Life? | Science
The thin layer of gases that stretch from Earth’s surface to the edge of space is more than just the air we breathe. This blanket of air—called the atmosphere—sets Earth apart from the other planets in our galaxy by supporting life.
To expand on your studies of Earth’s systems for the TASC Test Assessing Secondary Completion™ Science subtest, let’s take an in-depth look at the role the atmosphere plays in sustaining life on Earth.
Processes Within the Atmosphere
- Breathing: The air you inhale is a different mixture of gases than the air you exhale. This continuous exchange of gases is made possible by the atmosphere.
- Flight: Air movement over the wings of birds, insects, and airplanes creates an upward lift, making flight possible.
- Weather: Wind, rain, and snow depend on the atmosphere. Without rain water, or water from melting snow, plants and animals could not survive. The wind helps new plants to grow by carrying their seeds to new places, or helping to pollinate existing plants.
- Vegetation: Plants use the small amount of carbon dioxide found in the atmosphere to carry out the process of photosynthesis. Without it, there would be no supply of oxygen.
How the Atmosphere Protects Us
- It regulates Earth’s temperature. Known as the greenhouse effect, the atmosphere traps Earth’s surface heat, preventing it from radiating into space.
- It shields harmful radiation from the sun. While the sun gives off light and heat, two necessary things for life on Earth, it also sheds dangerous ultraviolet radiation. Without the atmosphere’s ability to filter most of this radiation, living cells would be destroyed at a staggering rate. It is important to note that some ultraviolet radiation still enters Earth’s atmosphere. Sunscreen protects us against two types of ultraviolet radiation — UVA and UVB — defending against skin damage, premature skin aging, and skin cancer.
- It destroys falling meteors. Pieces of rock travel into Earth’s atmosphere every day. Due to high amounts of friction in the atmosphere, most meteors burn up before they’re able to reach surface level. Those that don’t completely combust fall to Earth as meteorites.
Want to learn more? Stay tuned for the next TASC Science subtest post to learn about the five layers that make up Earth’s atmosphere.