Ozone layer barrier made life, only five millimeters

Ozone layer barrier made life, only five millimeters

About the Earth's atmosphere was able,
Volcanic gases and nitrogen such as hydrogen sulfide and carbon dioxide
It is thought that was the main component.
Early life that occurred there, the
Reserves of organic compounds have been synthesized by chemical reaction of natural
"Eat" was alive. You should of course if there are no reserve was Oshimai.
However, there is the appearance of oxygen (cyanobacteria) cyanobacteria perform photosynthesis
Begin to release, as long as there is a sustainable solar energy
Life cycle has started.
This is the scenario of the evolution of about two billion two years ago.
Oxygen, energy use due to oxidation,
And supporting the development of an organism to perform aerobic respiration that is
At the same time, in the atmosphere is changed to ozone in part by the sunlight,
Began to form a barrier to prevent the intense ultraviolet light.
Ozone layer, however, had emerged.


From sea to sea life near by it,
To expand the area to the ground and is now available.
The ozone layer, 10 km from the ground current
Widely distributed in the stratosphere near 50 km,
Actually is present as an area of ??fairly dilute ozone.
Under atmospheric pressure until the ground temporarily bring down the ozone layer
If you measured the thickness, not only to just five millimeters.
This thin barrier, called UV-B,
They also protect the life from ultraviolet rays that are capable of cutting a chemical bond.


However, the ozone layer is also a troubled existence in reverse.
Low ozone in the atmosphere has a greenhouse effect,
Causing pulmonary edema at high concentrations, respiratory and skin aging, even at low concentrations,
Harm and to promote carcinogenesis is because large.
Ozone generation is caused by industrial activity must be suppressed.
In 1982, Japan and the United Kingdom Antarctic team,
Than the average concentration of ozone over Antarctica
Got the data has been greatly reduced.
Discovery of the ozone hole is surprised the world.
And as a result of intensive research and intense debate of scientists,
Five years later, chlorine in the stratosphere is derived from the CFC
It came to be confirmed that interfere with the formation of ozone.


Now, is not only a decrease in ozone in the polar regions,
Has become significantly at mid-latitudes.
Sharp decline of amphibians, such as now, the absolute decline of wildlife,
Go in the world that is as well known.
Cause is complex, the impact of ozone depletion has been pointed out.
It has been most concerned about damage to humans, an increase of skin cancer,
Are also some movement to limit the activities of sunbathing and in the field.
Montreal Protocol of 1987, with subsequent further tightening of regulations,
The manufacture and use of CFCs has been banned or severely restricted,
Deterioration of the situation is being suppressed.
However, it stops the expansion of the ozone hole at the beginning of the next century
Is an unpredictable situation is whether.
The trend is the problem of the world's regulatory, legal regulations in Japan is the penalty
The question remains, such as point without.