Asked by: David, Camilleri Msida, Malta
The sheer scale of the notorious hole - or, more accurately, depleted region - in the Earth's ozone layer over the Antarctic beggars belief. At its peak each September, it spans an area bigger than the continental United States, and tens of millions of tonnes of ozone would be needed to fill it up again. Simply creating that amount of ozone, let alone getting it where it's needed, would be astronomically expensive.
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