Slashdot Mirror
Your Thoughts on the Great Ozone Debate?
Hrodvitnir asks: "Yesterday the BBC reported that the hole in the ozone layer above the Antarctic is the largest on record. Today CNN says that it is recovering, or at least stabilized. Do we really know what's going on? Is this more bad science/false studies, or are they both partially right?"
The reason they end up over the poles is because that's where the offending particles end up. To read about why this is so, visit here: Ozone Hole.
A blog like any other.
Here's a good link to the story...quite a bit of detail not present in either article cited in the submission.
Interesting that the sources that hold that the hole is gtting worse are European, while the sources that state everything's OK are American.....hmm....
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~ |rip/\/\aster /\/\onkey
The articles linked are both right in some sense, the article submission is wrong... the slashdot summary here says the 2005 hole is the "the largest on record", the BBC article it links says it is the largest on record since 2000, which was the actual all-time record...
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Both are completely right. An elaboration: Wheras the CNN article discusses the stabilization of ozone depletion, the BBC article discusses the size of the Antarctic ozone hole. The BBC piece says, in not so many words, that the size of the ozone depleted region was largest in 2000 and 2003, owing to biennial-ish seasonal fluctuations and weather conditions. The hole might be of similar size THIS year as well for the same reasons. However, to quote from the very same BBC article:
So then, both articles do indeed agree. They were not referring to separate conclusions on the same issue, but instead to different facets of the same phenomenon.Two years ago researchers produced the first evidence that damage to the ozone layer is slowing down; globally, they showed, destruction continues, but at a slower rate than before.
That is down to the Montreal Protocol, established in 1987, which has limited production and use of CFCs and related substances.
But the indications are that the ozone layer will not be back to its pre-industrial condition for at least another 50 years.
Carbon Dioxide has no impact on the ozone hole.
The ozone hole, which this article is about, is not connected to the separate problem of global climate change as a result of human-produced greenhouse gases. The ozone hole is also a problem which is easier to deal with; the CFCs and particles which cause ozone layer damage fall out of the atmosphere much faster than carbon dioxide.
Irritable, left-wing and possibly humorous bumper stickers and t-shirts
3) Ted Turner hasn't been intimately involved in what goes on with CNN for a decade (he sold CNN in 1995) and conservative Walter Isaacson moved the network very much to the right when he took over in 2001.
Cute explanation, but wrong. CFCs have a stratospheric halflife of 70-120 years, and catalyze ozone destruction, thus reducing the steady-state ozone level when balancing solar ozone creation and ozone destruction.
Basically, CFCs long life allows them to reach the stratosphere. There, they slowly break down, releasing a constant supply of chlorine ions. This participates in many reactions, most notably Cl + O3 -> ClO + O2; ClO + O -> Cl + O2. Note that the chlorine ion is still left over. This ion goes on to complete thousands of more reactions before it is ultimately lost (to a variety of mechanisms).
sed "s/SJW.*$/... never mind. I was about to say something stupid, and also, I'm a troglodyte./Ig"
No, the experiment I was aluding to was using ice core samples to determine if ozone depleting chemicals existed in nature before industrialization.
It is easy to figure out when the hole appeared because it happened in the last 100 years or so.