18 August 2011
Earth’s Atmosphere and Interior
Planet Earth, It’s our home in the universe. It’s also the birthplace of intelligent life and astronomy. In order to better understand our universe we must first understand our planet and planetary system of which we reside. By understanding Earth’s properties we can get a better grasp of the rest of our solar system. Earth is the best studied of all the terrestrial planets and also where our study of astronomy begins. In the following research paper I will cover topics such as Earth’s atmosphere, Earth’s Interior, Surface activity of the Earth, Earth’s magnetosphere, and Earth’s origin. From a human’s perspective, the most important part of the Earth’s atmosphere is the part in which we can live and breathe called the Troposphere. The air in which we breathe is a mixture of gases made up mostly of Nitrogen, Oxygen, Argon, and Carbon Dioxide. The presence of a very large amount of Oxygen makes us unique from any other planet in the solar system. Water, and Carbon Dioxide play a vital part in the workings of our planet and sustaining life on Earth. The portion of our atmosphere below 12km is called the Troposphere, and the portion 40 to 50 km above it is called the stratosphere. Between 50 and 80 km is the mesosphere, and above 80 km is the ionosphere. Atmospheric density decreases steadily as altitude increases. As altitude increase so does the pressure relative to ground level. Figure [ 1 ]Earth's Atmosphere
The troposphere is the area of Earth’s atmosphere in which convection takes place. It is the constant upwelling of warm air and the concurrent downward flow of cool air to physically take its place. When the Earth is heated by the sun, the air becomes warmer and expands therefore it becomes buoyant, less dense, and begins to rise. At higher altitudes the opposite effect occurs. The air cools down and becomes denser causing it to sink back down. A circulation pattern is established and convection occurs. The constant churning of convection cells is responsible for all of the weather we experience in our daily lives. Convection is also responsible for another phenomenon called turbulence. Ascending and descending parcels of air can cause a rough flight. Within the Stratosphere is the Ozone Layer. The Ozone layer is more or less a shield that serves to protect life on Earth from the harshness of outer space. Radiation and energetic particles from outer space are hazardous to humans, plants, and animals alike. Without the protective Ozone layer life on Earth’s surface would be almost impossible. Human technology has recently developed to a point where we are now doing measurable damage to our Ozone layer. The hole over the Antarctic continent is a region where climactic conditions and man-made chemicals combine to rob our atmosphere of its protective Ozone layer. The depth and area have grown significantly since the hole was discovered in the 1980’s. The next topic I will cover is Earth’s Interior. Although we live on the planet called Earth, We cannot easily probe and study Earth’s interior. No substance used for drilling, even diamond the hardest known material can withstand pressure below a depth of 10km. Earth’s interior is made up of four parts. They are the crust which is the outer region. The mantle which is 3000km thick and accounts for 80 percent of our planets volume, The Outer core being liquid and the inner core which is solid and extremely dense. The high central density of the Earth suggests to geologist that the inner parts of the earth must be rich in nickel and iron. The mantle of the earth is comprised of rocky material- compounds of silicon and oxygen. The core of the Earth consists primarily of even denser metallic elements. The core is a mixture of nickel iron and possibly some lighter materials such as sulfur. The pressure of the center of the Earth is said to be some 4...