[Hippikos]

Science does not stand still. New evidence appears constantly, and opinions change. Hippikos, you are entitled to hold onto your opinion, and you have obviously gone out of your way to do your own reading on the topic. Even though we disagree, I tip my hat to you for showing an interest.

Respect is mutual bluesdave. Fact is that I never see Earth´s own production of chlorine (100,000 times more) coming into the equation by the depletionists, neither the fact that CFC´s are 4,5 heavier than air, so how can they show up 40-50 km up in the air?

There´s no such thing as a "hole", just a mere decrease in ozone levels at some altitude over the South Pole. Some years it is bigger and other years is much smaller, following the sun's activity, or the QBO direction.

Note that the CSIRO started measuring ozone levels in 1956, but the hole as such was not discovered until the 1970s. Dobson's work is well recognised, and appreciated, but research has continued, and new light has been shed on the topic.

NOAA states that the ozone hole was discovered in the 80´s, so take your pick.

Science does not stand still. New evidence appears constantly,

I´m interested to learn these. CFC and PCB´s are banned for decades, still ozone holes occur, exclusively over the Antarctic.