How many gases make up the atmosphere

In respiration, oxygen is combined with glucose to chemically release energy for metabolism. The products of this reaction are water and carbon dioxide. The next most abundant gas on the table is water vapor. Water vapor varies in concentration in the atmosphere both spatially and temporally. The highest concentrations of water vapor are found near the equator over the oceans and tropical rain forests. Cold polar areas and subtropical continental deserts are locations where the volume of water vapor can approach zero percent.

Water vapor has several very important functional roles on our planet:. The fifth most abundant gas in the atmosphere is carbon dioxide. This increase is primarily due to human induced burning from fossil fuels, deforestation, and other forms of land-use change. Carbon dioxide is an important greenhouse gas. The human-caused increase in its concentration in the atmosphere has strengthened the greenhouse effect and has definitely contributed to global warming over the last years.

Carbon dioxide is also naturally exchanged between the atmosphere and life through the processes of photosynthesis and respiration. Methane is a very strong greenhouse gas. The primary sources for the additional methane added to the atmosphere in order of importance are: rice cultivation; domestic grazing animals; termites; landfills; coal mining; and, oil and gas extraction. Anaerobic conditions associated with rice paddy flooding results in the formation of methane gas.

However, an accurate estimate of how much methane is being produced from rice paddies has been difficult to ascertain. Nevertheless, scientists believe that the contribution of rice paddies is large because this form of crop production has more than doubled since Grazing animals release methane to the environment as a result of herbaceous digestion.

Some researchers believe the addition of methane from this source has more than quadrupled over the last century. Termites also release methane through similar processes. Land-use change in the tropics, due to deforestation, ranching, and farming, may be causing termite numbers to expand. If this assumption is correct, the contribution from these insects may be important. The Stratosphere is the layer at which most weather balloons fly.

The Mesosphere is where meteors mostly ignite. The Thermosphere is where the International Space Station orbits. Finally, the exosphere, being the outermost layer, is where you can find the lightest gases: hydrogen and helium.

Many properties of the gases in the atmosphere are dependent on the altitude at which they are found. For instance, average density of these gases generally decrease as one rises to higher altitudes. As a result, the pressure being due to the collisions of the particles that make up the gas also decreases in the same manner. Since the force of gravity pulls down on the masses of these gases, the heavier gases are typically found near the surface of the Earth while the lightest ones e.

Temperatures decrease in the mesosphere with altitude. The thermosphere is located above the mesopause and reaches out to around kilometers miles. Not much is known about the thermosphere except that temperatures increase with altitude. The uppermost layer, that blends with what is considered to be outer space, is the exosphere. Also called a shooting star or falling star. The audio, illustrations, photos, and videos are credited beneath the media asset, except for promotional images, which generally link to another page that contains the media credit.

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