【英语时差8,16】创造臭氧层-下（在线收听）

No. No? No, we can't manufacture enough ozon to replenish the ozon hole. why not? Several reasons, for one thing, ozone in large quantities is extremely hazardous and volatile, which makes it hard to work with, to say the least. Also, the ozone layer is immense–there’s roughly twenty billion tons of it–and we’d have no way of handling such large quantities. Plus, the ozone layer requires a huge amount of energy to maintain itself, which right now it gets from the sun. Taking over natural ozone production would require more than double the energy the United States produces annually. And that’s why the only way we know to fight ozone depletion is by cleaning up our act and giving nature the chance to take its course.