Air is important for the planet because it contains the gases necessary to support plants, animals and other organisms. Additionally, the presence of an atmosphere keeps the Earth at a habitable temperature.Continue Reading
The air on planet Earth is largely comprised of nitrogen and oxygen. Nitrogen is inert and does not affect most living organisms; however, all living animals require oxygen to survive. Plants require carbon dioxide to survive, which is also found in the earth’s atmosphere. Some bacteria require oxygen, but others are called anaerobic species, and they do not require oxygen. The balance of the various components of the atmosphere is very important to life on the planet.
If the world had no atmosphere, it would be very cold. Astronomers studying other planets know that planets without atmospheres have wildly fluctuating temperatures or they are cold all the time. The Earth’s air helps to moderate the temperature and make it a habitable place for living organisms.
The chemistry of the air surrounding the earth is very important. Currently, the world is warming as the ratio of carbon dioxide, methane and other gases increases. These chemicals are called greenhouse gases because they cause the planet to warm up, just as a greenhouse does.Learn more about Atmosphere
Air seems thinner at high altitudes because air pressure is lower, which allows individual air molecules to occupy a larger volume than air molecules do at low altitudes. This decreasing pressure with increasing altitude occurs because there are increasingly fewer air molecules exerting pressure on the next-lowest altitude.Full Answer >
Air cools when it rises through the atmosphere because as altitude increases, air pressure decreases and allows the individual air molecules to expand away from each other. This expansion leads to a decrease in collisions between air molecules, which then results in less heat energy being transferred between those molecules.Full Answer >
In the thermosphere, the three major gases making up the air are atomic oxygen, atomic nitrogen and helium. Unlike below the mesopause, the gas components of the thermosphere are separated based on their chemical elements.Full Answer >
The three main gases found in the Earth's air are nitrogen, oxygen and water vapor. A typical volume of air at sea level at 15 degrees Celsius contains approximately 78 percent nitrogen, 21 percent oxygen and between 1 and 5 percent water vapor.Full Answer >