By reducing CFCs to repair the damage to the ozone layer, we also reduced greenhouse gases in our atmosphere. Of course at the time people opposed to the Montreal Protocol had all sorts of arguments as to why it was a bad idea. It is a good thing we did not listen.
- The science is not certain
- The ozone layer is not getting thinner
- It would be disastrous to the economy to ban CFCs
- Humans are not the cause of the loss of the ozone layer
I wonder where I have heard these before.
What’s good for the ozone layer has been even better for Earth’s climate. According to a new study, a 20-year-old ban on ozone-depleting chemicals has been extremely effective at curbing greenhouse gases as well. In fact, it has already had more impact than a fully implemented Kyoto Protocol would have accomplished…
In 1987, the Montreal Protocol was ratified by 191 countries to curb CFC emissions from sources such as refrigeration, dry cleaning, and foam insulation. The strategy has been effective: The rise in atmospheric concentrations of CFCs has been arrested, and the ozone layer has begun to show signs of recovery, to the point where scientists predict it will heal completely sometime after 2050.
The real surprise, though, is the dramatic impact the reduction of CFCs has already had on global climate change. In a paper published online this week in the Proceedings of the National Academy of Sciences, Velders and colleagues calculate that since 1987, gradually shutting down CFC emissions has removed the equivalent of about 11 billion metric tons of carbon dioxide from the atmosphere (or about 0.55 billion tons per year that the Montreal Protocol has been active). By comparison, even if the Kyoto Protocol had been fully ratified (the United States and Australia, among others, have not signed on) it would have removed only about 2 billion tons of carbon dioxide thus far (or about 0.25 billion tons per year that the Kyoto Protocol has been active). So for CO2 emissions curbs to match the impact of the ban on ozone-depleting chemicals, they would have had to be over five times more restrictive.
While this is great news it does seem to indicate that the Kyoto Protocol was not enough, and that green house gas emissions will have to be eventually reduced even further.