ENVIRONMENT

Environment

Environment

When we decided to look for life on another planet or satellite, one of the most important is whether or not it has atmosphere. The reason is that if there is no atmosphere the surface temperature can vary over a hundred degrees between day and night, as happens on the moon, and this is incompatible with life. Therefore, it is because of the atmosphere that our planet is liveable. It is sometimes said that is because of the atmosphere containing oxygen is living on Earth. It's actually just the opposite. It was thanks to living beings, specifically cyanobacteria that 3500 million years ago began to perform photosynthesis, which is no oxygen in our atmosphere. Currently we are endangering this layer (global warming, ozone layer, acid rain, etc) and need help, because we are endangering the survival of future generations. In addition, many forms of terrestrial life may still exist with an atmosphere very different from today but we do not. Then find lots of information on this layer (Kotak et.al, 1994, p. 37-40).

This essay will summarize and review the topic of the determination of the concentration of oxygen in the terrestrial atmosphere.

Discussion

Oxygen is the most abundant element in Earth's crust. In the atmosphere, it is about 23 wt%, in the water - about 89% in humans - about 65%, the sand contains 53% oxygen in the clay -56%, etc. If you calculate the amount in the air (atmosphere), water (hydrosphere) and accessible direct chemical study of the solid crust (lithosphere), we find that the share of oxygen accounts for about 50% of their total mass (Wilcock, 1995, p. 277-288). Free oxygen is contained almost exclusively in the atmosphere, and the number is estimated at 15 tons 1.210 despite the enormity of this magnitude does not exceed 0.0001 total oxygen content in the earth's crust.

What was the impetus for the emergence of the atmosphere on Earth and what gases was part of the Archean atmosphere? On our planet, at first did not have any atmosphere. Probably, the molecules of gases by heat of the planet flew into space. In the primary Earth, there were a lot of active volcanoes. They were thrown out during the eruption of steam, dust, and many gases, including carbon dioxide, nitrogen, carbon monoxide, sulphur fumes. But the planet at this time was still so warm that the gases cannot condense (Wilcock, 1995, p. 277-288). As the temperature of the planet in an atmosphere of water appeared, not only gaseous, and liquid, and further cooling rains began to fall.

At the Earth's surface has a hot rain had fallen, and boil in a pair of returning to the atmosphere. This process is accelerated and the cooling Earth's surface. Much of the precipitated water quickly found a way of beginning to form in the oceans. Volcanic eruptions have continued to supply the atmosphere with water vapour, which will eventually replenish stocks of liquid water on the planet. Much of the carbon dioxide is easily soluble in water, washed out ...