Where did you hear that? CFCs can linger in the atmosphere for 50-100 years, so recovery is a slow process. It took more than a decade after the Montreal Protocol went into effect before the hole in the ozone layer stopped growing. Additionally, different parts of the ozone layer will recover at different rates:
Where did you hear that? CFCs can linger in the atmosphere for 50-100 years, so recovery is a slow process. It took more than a decade after the Montreal Protocol went into effect before the hole in the ozone layer stopped growing. Additionally, different parts of the ozone layer will recover at different rates: