Saturday, December 24, 2011

Physics Concept: Atmosphere and Weather


Atmosphere is the layer of air that surrounds the earth. The air is a gas object consisting of a variety of gases, dust, moisture and other particles. This will protect the earths from excessive solar radiation and meteor hit (the rocks) derived from space. In addition, the atmosphere is the medium for the cloud, due to the position of the Earth 32 ½ tilted to the plane of orbit, causing weather patterns are not the same as every part of the world long the year. Movement of air in the atmosphere sometimes also cause havoc such as hurricanes that hit many areas on the surface of this earth. Because of this atmosphere influence eventually evolved sciences such as climatology, meteorology and geophysics.

The atmosphere consists of layers of gas to a height of 80 km of gas composition in the atmosphere can be said uniform. In the dry state of the air composition is largely made up of:
Nitrogen                      78%
Oxygen                       21%
Carbon dioxide           0.03%
Noble gases                 0.936%
Water vapor and dust Uncertain


Nitrogen in the atmosphere is difficult to compound with other elements and can be said of a neutral substance. Small amounts of nitrogen are soil bacteria that are beneficial to the plants. Nitrogen also plays a role in combustion. Nitrogen is chemically inactive. So slow down the oxidation of nitrogen or oxygen incorporation process.

Oxygen is an element of active compound with other elements in the process of oxidation. Oxygen in the atmosphere can be a source of fire, because fire can occur because of mixing of oxygen with the carbon contained in charcoal, oil, wood and other fuels. Oxygen is needed by the organisms to convert food into energy now. We breathe oxygen into the lungs and blood oxygen channeling to the entire body. Oxygen is mixed with carbon in the cell body so occurs heat, energy and combustion of residual carbon dioxide, which released from the body when breathed.
The role of carbon dioxide in the air because can absorb solar radiant heat. For plants CO2 use to convert nutrients into carbohydrates in the process of photosynthesis.
The higher the percentage of air layer is a light substance such as H2, while the greater the weight substances such as N2, O2 and water relative dwindle
Some types of gases which are atmosphere will vary depending on the process that occurs in the earth, atmosphere and sun. Water vapor, carbon dioxide and ozone gases Brazilians number of changes, which affect weather patterns and climate.
1.      Water vapor can be transformed into water (liquid) or solid (ice)
2.      Carbon dioxide can be a condensation nucleus the greenhouse effect and increase atmospheric temperature.
3.      Ozone (O3) is a gas that can absorb ultraviolet rays that are at high 20-30 km from the earth's surface. Ultraviolet rays are the rays that have a high chemical effect that could endanger life, especially human
4.      In addition, dust, smoke and salt crystals from evaporation of sea water will also change to change. Dust particles that are hygroscopic may act at the core condensation to form a thick, dark layer that can disrupt traffic and block the sunlight to enter. Dust also can reflect, absorb, and scatter radiation that comes from the sun.
Atmospheric layers can be distinguished based on changes temperature against altitude, as depicted in Figure below.

Atmosphere layer
1.      Troposphere is a layer of still air that lets people interact in a familiar, because the air is how we can breathe in the air is also weather and climate. Troposphere is part of the atmosphere there with an average thickness of 0 to 10 km and an average temperature of about -500 C. troposphere temperature decrease caused very little soil to absorb short-wave and absorb solar radiation. In layer troposphere more water vapor and carbon dioxide than other layers, where the two gases can measure the balance of the earth, especially to infrared radiation. Carbon dioxide and water vapor may block the infrared rays radiated back from the land affected by the hot rays of the sun.
2.      Tropopause, the layer is an insulating or barrier with a layer of the stratosphere. This layer is very cold (-40 and in the polar region -80 in the equatorial / equatorial) and the temperature fixed. The thickness of this layer 6 km in the Polar Regions and 18 km at the equator.
3.      Stratosphere, situated at an altitude of 16-49 km. higher temperatures in accordance with the added height. The density of this layer is less dense than the layer under. Air layer is composed of the gases contained in troposphere, except for water vapor fewer. Layers consist certain items may form a sulfate-containing rain and ozone will protect from solar radiation mainly ultraviolet rays, so the levels of ultra violet to the surface of the earth safe for humans.
4.      Strotopause, located above stratosphere below the mesosphere at an altitude of 60 km. temperature order of 00 C and has a temperature discontinuities.
5.      Mesosphere, located at an altitude of about 60 to 85 km. mesosphere layer on carbon dioxide and water vapor less important, the density of other gases also have somewhat reduced. Mesosphere have a layer of ions or air that has a layer of electric charge called the 'D', this is caused by the presence of ultraviolet light on air molecules which met with an electron or a negative electrical charge. Decrease in average temperatures of 0.40 C per 100 m caused by a negative radiation balance. This layer is the place where the meteor burned by hot events mechanical (friction) with air.
6.      Mesopause, a layer with low temperature limit mesofir -1000 C with thermosphere. This layer is located at an altitude of 85 km.
7.      Thermosphere. Layer 85 km up to 200 or 300 km. This layer mark with extreme temperature rise from -1000 C to thousands of degrees Celsius. The density of the thermosphere is very low, less than a quarter million air density on the surface of the earth. However, although thin, air in the thermosphere enough dense to burn the meteor that was headed down at an altitude of 300 km. almost all gas atoms in the thermosphere layer containing an electric charge, or ionized by solar radiation, etc.
8.      Termopause. The highest layer in the atmosphere ranging in altitude of 200 km or 300 km to 1000 km. This layer has a relatively constant temperature with the difference that occurs because of differences in day and night. Daily amplitude at 1000-2000K daylight and at night 600-1500K

For furthermore explanation, download the doc and ppt file as follow.

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