Earth's Atmosphere
By: Camden Fuerst
Introduction
Can you picture not being able to breathe? Being cold every time you go outside? Not having the ability to speak? These and many other things that are a part of everyday lives that occur due to Earth's atmosphere. All living things could not survive without the atmosphere. The atmosphere is made of many different gases and is split into four main layers. There are different types of instruments that are used to measure air pressure and density. The air pressure and density is affected by altitude. The atmosphere is an extremely important factor to Earth.
Composition of Earth's Atmosphere
The composition of Earth's atmosphere contains many different gases. It is composed of....
- nitrogen(78%)
- oxygen(21%)
- argon(1%)
- small amounts of carbon dioxide, neon, helium, methane, krypton, hydrogen, nitrous oxide, xenon, ozone, iodine, carbon monoxide, ammonia, and water vapor
Composition of Earth's Atmosphere
Importance of Atmosphere
The atmosphere is extremely important to living things on Earth. It allows for us to breathe, due to its oxygen. It also protects us from dangerous sun rays by blocking them out. It keeps us warm by keeping all of the heat inside the atmosphere. It gives us weather, allowing for rain to water plants and go through photosynthesis. It also stops meteoroids from flying and hitting Earth. The carbon dioxide allow for plants to carry through photosynthesis. Birds and planes are able to fly because of the atmosphere, allowing for travel. It also lets us talk by carrying vibrations made by your vocal cords. Without the Earth's atmosphere, living things would not be able to survive.
Formula used to calculate density
Density is calulated using mass divided by volume.
Air Pressure
The closer to sea level, the higher the air pressure. As you reach higher altitiudes, the lower the air pressure.
Density
The warmer the air, the less dense it is. The cooler the air, the higher the desnity is.
Properties of Air
Air may seem to have no mass, but it actually does due to the atoms and molecules that make up the air. Due to the air mass, it also has properties such as density and pressure. The density is the amount of mass in a given volume. The greater amount of molecules, the greater the density. The fewer amount of molecules, the density is lower. The pressure is the force pushing down on an surface or area. Air pressure is the result of the weight a column of air pushing down on an area. The atmosphere of Earth is very heavy. It does not crush you because the molecules push in all different directions. The air pressure changes from day to day.
Instruments used to study Air
To know what is happening to the air, especially the air pressure, we use many different instruments. Barometers are instruments use to study air pressure. Two common barometers are mercury barometers and aneroid barometers.
A mercury barometer is a tube open at the bottom end and partially filled with mercury. The space above the tube works similar to a vacuum and has very little air. At the open end of the tube ot rests in a dish filled with mercury. The greater the air pressure, the higher the mercury is pushed up. The lower the air pressure, the lower the mercury rises.
An aneroid barometer has a metal chamber that is sensitive to air pressure. As pressure increases, the walls of the chamber become thin. As the pressure decreases the walls budge out. The chamber is conmected to springs and levers. As the shape of the chamber changes, the needle on the barometer moves.
Altitude, Air Pressure, and Density
Altitude effects both density and air pressure. Air pressure decreases as you increase in altitide because the the higher the altitude, the less things are being pushed down than at a lower altitude. Density decreases as the altitude increases. The higher the altitude, the farther apart molecules are, making the density lower than when the altitude is low, when the molecules are closer together making for a higher density.
Main Layers of the Atmosphere
The atmosphere is split into four main layers, the troposphere, stratosphere, mesosphere, and thermosphere. These layers are split up by scientists because they are classified by changes in temperature.
Troposphere
The troposphere is the layer of the atmosphere closest to Earth. It extends from about 10-15 kilometers above Earth's surface. 75% of the atmosphere's mass is located in the troposphere. Temperature and pressure decreases as altitude increases. The troposphere is the layer in which Earth's weather occurs.
Stratosphere
The stratosphere is the layer of the atmosphere located above the troposphere. It extends from about 15-50 kilometers above Earth's surface. This layer contains the ozone layer. The top of this layer is warmer than the bottom of the layer. This is due to the ozone layer, which contains the most ozone in this layer and absorbs the sun's energy, making it warmer. The ozone layer protects Earth from dangerous sun rays.
Mesosphere
The mesosphere is the layer of the atmosphere that is located above the stratosphere. It extends from about 50-80 kilometers above Earth's surface. This is the layer where temperature decreases with increasing altitude. The mesosphere is the layer in the atmosphere that has air thick enough to slow down meteoriods to prevent them from hitting Earth.
Thermosphere
The thermosphere is the final layer of the atmosphere located above the mesosphere. It extends from 80 kilometers above Earth's surface and reaches to outer space. This layer is very warm because the sun's energy reaches this layer first. You would not feel the heat because the molecules move fast, but they are so spread apart you cannot feel the energy. The thermosphere is split into two layers. The bottom layer is the ionosphere. It extends from about 80 kilometers to 400 kilometers. Energy from the sun causes the particles to become ionized due to the ultraviolet light. These particles glow, creating the Northern Lights. The exosphere is the top layer of the thermosphere. It extends from about 400 kilometers to thousands of kilometers outward. Its name comes from the term "exo", meaning outer.