An inconvenient truth

[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.

[bluesdave]

Originally Posted by Hippikos

NOAA states that the ozone hole was discovered in the 80´s, so take your pick.I´m interested to learn these. CFC and PCB´s are banned for decades, still ozone holes occur, exclusively over the Antarctic.

I stand corrected. The decrease in ozone levels was being hilighted through the 70s and the "hole" actually discovered in the early 80s. It will take at least 50 years for the lost ozone to be replaced, and that is assuming that the developing world does not spew out CFCs and halons.

Here is a quote explaining how the hole occurs:

Why does the ozone hole occur over Antarctica?
Human emissions of CFCs occur mainly in the Northern Hemisphere. Gases such as CFCs which are insoluble in water and relatively unreactive are mixed within a year or two throughout the lower 10 kilometres of the atmosphere (the troposphere). The CFCs then rise from the lower atmosphere into the stratosphere, mainly in the tropics. Winds then move this air poleward - both North and South - from the tropics. The meteorologies of the two polar regions are very different. The South Pole is part of a very large land mass that is completely surrounded by ocean. These conditions produce a very cold stratosphere which leads to the formation of clouds. The clouds that form lead to chemical changes that promote rapid ozone depletion. The North Pole lacks the land/ocean symmetry of the South Pole. As a consequence the stratospheric air is much warmer and fewer clouds form. Therefore the ozone depletion in the Arctic is very much less than in the Antarctic.

[bluesdave]

Coincidently, Goddard has just released a report that the ozone hole has just reached its largest area, and depth!

[xoxoxoBruce]

Originally Posted by Hippikos

snip~
There´s no such thing as a "hole", just a mere decrease in ozone levels at some altitude over the South Pole.

From Dave's "Goddard" link;

Scientists from NOAA's Earth System Research Laboratory in Boulder, Colo., use balloon-borne instruments to measure ozone directly over the South Pole. By Oct. 9, the total column ozone had plunged to 93 DU from approximately 300 DU in mid-July. More importantly, nearly all of the ozone in the layer between eight and 13 miles above the Earth's surface had been destroyed. In this critical layer, the instrument measured a record low of only 1.2 DU., having rapidly plunged from an average non-hole reading of 125 DU in July and August.

That would seem to agree that the "hole" is a thinning, rather than an absence, we would normally associate with "hole". I suspect the use of the word "hole", was a media concoction.

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

From Dave's "this link";

CFC's take up to 15 years to reach the stratosphere but can stay in the atmospere from 50-200 years. This means that the relatively small depletions in ozone seen now will get much larger as CFC's that have already been released accumulate in the stratosphere.

Originally Posted by Hippikos

Chlorine atoms can ONLY react with ozone on the hard ice crystals in the surface of the SPC (stratosphere polar clouds) in Antarctica. As SPC forms ONLY in Antarctica during the winter and spring (they do not form over the Arctic, because the Arctic’s stratosphere is not cold enough), the logical conclusion is that chlorine do not react with the ozone layer in the rest of the world. That’s a fact. But recognizing this fact would show the ozone depletion theory is a fake, and would deprive scientists milking the “ozone scare cow” of the so much needed money to survive.

Wouldn't that be like a swimming pool filter cleaning the water and dumping it in one spot? Eventually the water gets circulated throughout the pool and it all gets cleaner.
So just because the ozone is only being destroyed over the Antarctic, it's still depleting the total we have, unless it's being produced fast enough to make up for that loss, elsewhere.

Thanks to both Youze Guys for the insightful input.....and Dave, thank your boss for us.