Reducing Ozone Depletion
Introduced| English | Meaning |
|---|---|
| Montreal Protocol/ˌmɒntrɪˈɔːl ˈprəʊtəkɒl/ | An international agreement protecting the ozone layer by controlling and phasing out the production and consumption of ozone-depleting substances. |
| substitutes/ˈsʌbstɪtjuːts/ | Goods or services that can be used in place of each other. |
| recover/rɪˈkʌvə/ | recover |
A problem the world solved
- Ozone depletion could have been a disaster.
- Instead, it became a rare environmental success story.
- The world noticed the danger and acted together.
- The ozone layer is now slowly healing.
The Montreal Protocol
- In 1987, nations signed the Montreal Protocol 蒙特利尔议定书.
- They agreed to phase out CFCs and similar chemicals.
- Almost every country in the world joined.
- It is one of the most successful treaties ever made.
A chlorine atom from a CFC destroys ozone in a repeating cycle
The Montreal Protocol was a global agreement to…
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The Montreal Protocol (1987) had countries agree to phase out CFCs — a rare global success.
Safer substitutes
- Industry developed substitutes 替代品 for CFCs.
- These new chemicals cool and spray without harming ozone.
- Old fridge and air-conditioner coolants are recycled safely.
- So daily life continued while the danger was removed.
Helps or harms the ozone layer?
Sort each action by whether it helps the ozone layer recover or keeps harming it.
To replace CFCs, industries switched to…
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Companies developed substitutes that cool and spray without harming the ozone layer.
Because CFCs were banned, the ozone layer is slowly starting to ____.
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With CFCs falling, the ozone layer is beginning to recover — proof that global action works.
Slow but real recovery
- CFCs already in the air last for decades.
- So the ozone layer heals slowly, not overnight.
- But measurements show it is starting to recover 恢复.
- Scientists expect it to fully heal later this century.
The ozone layer recovered within a few years of the CFC ban.
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False. CFCs already released last for decades in the stratosphere, so recovery is slow and is expected to take until the middle of this century.
Select all actions that help the ozone layer.
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Banning CFCs, using substitutes, and recycling coolants all help. Releasing more CFCs harms.
Ozone recovery is the environmental movement's best proof that global cooperation works. The world identified a threat, agreed a binding treaty, replaced the harmful chemicals, and the problem is reversing. But note the lag: because CFCs linger for decades, recovery is slow even after the ban. Acting early matters — the longer a persistent pollutant is released, the longer the damage lasts.
Why it worked:
- Scientists proved CFCs were thinning the ozone layer, and the danger was clear.
- Nations signed the Montreal Protocol and industry switched to ozone-safe substitutes — fridges and sprays kept working.
- Decades later, satellite data shows the ozone hole shrinking and the layer starting to recover — a problem caught, agreed on, and reversed.
Ozone depletion was reversed by global action. The Montreal Protocol (1987) phased out CFCs worldwide, and industry switched to ozone-safe substitutes. Because CFCs linger for decades, the layer heals slowly, but it is now starting to recover — a rare success showing that international cooperation can fix a global problem.