更多"41)__________. The mystery involves"的相关试题:
[填空题]41)__________. The mystery involves a change in the atmoshpere—a hole, or thinning, of the ozone in the atmosphere over Antarctica. Scientists were not sure what was causing it.
42) __________. It is found both in the air we breathe and in the upper atmosphere. Near the earth, ozone in the air is a danger to life. It is a pollutant. But ozone found 10 kilometers to 50 kilometers up in the atmosphere protects life on earth. Ozone forms in the atmosphere through the action of solar radiation. Once formed, the ozone blocks harmful radiation from reaching the earth. Scientists say a decrease in ozone and an increase in the harmful radiation will cause many more cases of skin cancer and will harm crops, animals and fish.
43) __________.
Chlorine is released into the air from the chlorofluorocarbons—or CFCs—used in plastic, air conditioners and spray cans. The use of CFCs has greatly increased worldwide since 1960 and is continuing to increase. The destruction of the ozone in