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Ozone： Shield Of Earth
Ozone consists of 3 oxygen atoms， has special “stink” smell， and spreads over the Stratosphere. The ozone sphere 20 to 30 kilometers high from the land has the densest ozone. Ozone is a substance with unstable chemical property and strong oxidizing property. Its forming and breaking down close related with the solar radiation. In the standard scenario， if all the ozone in the air is gathered together， its average thickness on the earth is only 3 millimeters， as the thickness of two 5 cent coins. The total ozone is always measured by the Dobson Unit （DU）. One DU means the cumulative thickness in the standard scenario is 0.01 kilometers， and 3 kilometers is 300 DU.
Don’t underestimate the 3 kilometers of ozone sphere， it absorbs plenty of the ultraviolet radiations from the sun. 95% of the most harmful UV-8 radiations for living things are absorbed. So it makes big differences on the global ecological system and the atmospheric environment. You can say that the ozone sphere is the shield to protect lives on the earth. Without the ozone sphere， the earth we are living on won’t resist the harmful ultraviolet radiations from the sun， and lives on the earth will all die.
Different Ozone Hole
In The Antarctic
Year After Year
Since the end of 1970s， the total ozone has began to reduce， especially in the Antarctic region. In the middle of 1980s， the Japanese and English scientists successfully found that the total ozone at the Antarctic station in spring had reduced by 30% to 40% compared to that of ten years ago. Then the American scientists confirmed it through the satellite data. In spring， the total ozone in the Antarctic sharply reduces， less than the average level by 30% to 40%. It seems like a low zone “hole” over the Antarctic， that is called the ozone hole in the Antarctic.
The Antarctic ozone hole doesn’t exist all over the year， but only in spring. Usually， the Antarctic zone begins to reduce from the later July， and a obvious ozone hole will form in the middle of August. The area of ozone hole will be the biggest from later September to early October. The total ozone will sharply increase from later October， and the ozone hole is gradually filled up. It will come back to normal in the middle of December， and there is no more ozone hole.
Ozone consists of 3 oxygen atoms， has special “stink” smell， and spreads over the Stratosphere. The ozone sphere 20 to 30 kilometers high from the land has the densest ozone. Ozone is a substance with unstable chemical property and strong oxidizing property. Its forming and breaking down close related with the solar radiation. In the standard scenario， if all the ozone in the air is gathered together， its average thickness on the earth is only 3 millimeters， as the thickness of two 5 cent coins. The total ozone is always measured by the Dobson Unit （DU）. One DU means the cumulative thickness in the standard scenario is 0.01 kilometers， and 3 kilometers is 300 DU.
Don’t underestimate the 3 kilometers of ozone sphere， it absorbs plenty of the ultraviolet radiations from the sun. 95% of the most harmful UV-8 radiations for living things are absorbed. So it makes big differences on the global ecological system and the atmospheric environment. You can say that the ozone sphere is the shield to protect lives on the earth. Without the ozone sphere， the earth we are living on won’t resist the harmful ultraviolet radiations from the sun， and lives on the earth will all die.
Different Ozone Hole
In The Antarctic
Year After Year
Since the end of 1970s， the total ozone has began to reduce， especially in the Antarctic region. In the middle of 1980s， the Japanese and English scientists successfully found that the total ozone at the Antarctic station in spring had reduced by 30% to 40% compared to that of ten years ago. Then the American scientists confirmed it through the satellite data. In spring， the total ozone in the Antarctic sharply reduces， less than the average level by 30% to 40%. It seems like a low zone “hole” over the Antarctic， that is called the ozone hole in the Antarctic.
The Antarctic ozone hole doesn’t exist all over the year， but only in spring. Usually， the Antarctic zone begins to reduce from the later July， and a obvious ozone hole will form in the middle of August. The area of ozone hole will be the biggest from later September to early October. The total ozone will sharply increase from later October， and the ozone hole is gradually filled up. It will come back to normal in the middle of December， and there is no more ozone hole.