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Over the Antarctic, the Smallest Ozone Hole In a Decade
hypnosec writes "The ozone layer seems to be on a road to recovery over Antarctica; according to Europe's MetOp weather satellite, which is monitoring atmospheric ozone, the hole over the South Pole in 2012 was the smallest it's been in the last 10 years. The decrease in size of the hole is probably the result of reduction in the concentration of CFCs, especially since the mid-1990s, because of international agreements like the Montreal Protocol."
Except that these processes are simple enough that we can measure the high altitude concentrations of these compounds and show that their influence on the O3 concentration closely matches our understanding of the processes involved.
Ezekiel 23:20
No. The hole in the ozone is caused by chlorine in the stratosphere, which gets there in chloroflorocarbons, catalyzing the O3 generated by the radiation in the upper atmosphere. It has nothing to do with climate change or greenhouse gasses.
Surely if it's been shrinking all this time then you could have the same story every day: "ozone hole smallest size since $date". Has it grown occasionally for some reason?
For reasons that are sufficiently messy that I certainly couldn't do them justice(and there really isn't any point in copy/pasting a pretend understanding from wikipedia and just wasting space) ozone levels vary considerably over time, both because of natural seasonal weather patterns and because of changes in the presence of various ozone-depleting synthetic compounds.
My understanding is that trends on atmospheric concentration of more or less all of the really nasty ozone-depleting compounds have been positive since regulation went into effect; but that the size and shape of the ozone hole has been a great deal more chaotic from season to season(shape counts, for our purposes, because ozone thinning over the antarctic is a bad sign; but the number of epidemiologists who care about penguin melanoma is limited, while ozone thinning over Australia is directly troublesome).
Good job misrepresenting that. Here, let me post the abstract, literally the first thing you'd read:
This Letter reports reliable satellite data in the period of 1980–2007 covering two full 11-yr cosmic ray (CR) cycles, clearly showing the correlation between CRs and ozone depletion, especially the polar ozone loss (hole) over Antarctica. The results provide strong evidence of the physical mechanism that the CR-driven electron-induced reaction of halogenated molecules plays the dominant role in causing the ozone hole. Moreover, this mechanism predicts one of the severest ozone losses in 2008–2009 and probably another large hole around 2019–2020, according to the 11-yr CR cycle.
The paper does not say it's dependent on cosmic rays exclusively, instead it points out that cosmic ray activity seems to play a significant role in determining the activity of halogenated molecules destroying ozone. Guess which one of those parameters we've totally screwed around with from the 1970s onwards?
I'll give you a hint: it's not cosmic ray irradiation.