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?"

Comments

Re:What I've always wondered

[mOoZik]

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.

Another Link

[TripMaster Monkey]

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....

Well, sort of

[mcc]

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...

Re:Easy

[lightyear4]

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:

• 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.

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.

Ozone Hole != Global Warming

[mcc]

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.

Ozone

[Mark of THE CITY]

Who wants ozone? Believe it or not, Los Angeles!

The city water department makes ozone to disinfect drinking water. It produces essentially zero carcinogens compared to chlorine. Because ozone can't be relied on to prevent contamination downstream of the treatment plant, chloramine is added as a final step. Any excess ozone is destroyed by catalytic degradation.

I saw this plant roughly 18 years ago when it was dedicated. It's near Sylmar, and was installed to treat water from the formerly prisine, but now less so, Owens Valley.

CNN: thanks to Ted Turner.

[Elder Entropist]

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.

Re:CNN: thanks to Ted Turner.

[demachina]

They've put out a lot of political proclamations in the last day or two to make it look like they are doing something but you can see the situation on the ground and tell they in fact did next to nothing in reality during the first 4 days of the disaster other than the obvious, they did get helicopters in to pluck people off of roof tops. That is the only part of the entire effort that seems to have worked. Only problem is once they were rescued they were dropped in collection areas with no drinking water and are dehydrating.

I heard with interest the head of the Coast Guard describing their work and again search and rescue was great, but much of its resources are going to:

A. Buoy replacement to get commercial shipping flowing again

B. Repairing the off shore oil capacity in the Gulf.

Those things are important, but you can consistently tell the Bush administration is more focused on getting the oil industry back on its feet over keeping thousands of poor blacks in New Orleans alive by getting them fresh water. I certainly want gasoline supplies to stabilize but I imagine I would rather people didn't die of dehydration and from drinking contaminated water because we are busy trying to gettin Exxon and Shell on their feet instead.

The obvious complete failure is FEMA should have requisitioned trucks from all points available and started trucking food and water, especially water to the survivors. Private groups and individuals have started doing it because FEMA failed completely in this most basic obvious part of ANY recovery. They didn't get fresh water in to the disaster area. People can survive a distaster without food for a while but people don't last long without water, and when they get thirsty the drink contaminated water, get sick and die. You would think the Republicans would remember the importance of drinking water from the Terry Schiavo case. You only wish they had placed the same importance on this as they did that. They rush Congress in from all points to pass a pointless resolution about here. Congress hasn't yet reconvened or done anything for New Orleans.

I seem to recall yesterday FEMA saying the supplies were en route but it could easily take four days before they actually started getting distributed because of all the Federal, state and local channels they had to be routed through.

One also has to wonder how much of the National Guard's equipment is in Iraq, for example water treatment plants, water and fuel tankers, trucks in particular. 1/3 to 1/4 of the Guard in the disaster area were unavailable because they are in Iraq, you have to wonder how much of the the equipment vital for disaster relief is there too.

Not sure how it will come out in the post mortem investigation but I saw a post here yesterday in which a study in 2004 indicated the levies in New Orleans were in dire need of repair and the money for their repair had been diverted by the Bush administration from the Army Corps of Engineers to the war in Iraq and to homeland security. If that proves to be the case you can scratch one city thanks to the incompetence of the Bush administration.

Re:I will explain something to you

[Rei]

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).

Re:Easy......

[d34thm0nk3y]

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.

Re:We can't even agree on global warming

[lgw]

There's no evidence that the Earths diminishing magnetic field is related to global warming, but there is a strong correspondence between solar activity and global warming for as long as we have records on both. It's not immediately obvious why solar activity would affect temperatures on Earth (not solar temperature or radiation output, which are nearly constant, but activity such as sunspots).

I do, however, find the disappearance of the Earth's magnetic field quite troubling. Given that it's pretty important to surviving solar radiation to begin with, and is merely a symptom of something even more mysterious happening in the core, it could be quite dangerous. I guess it's not interesting to people who want to use global warming as a weapon for their pet political cause (since it's clearly unrelated to human activity) so it doesn't get any attention.

The Earth's crust more or less floats over the solid inner core, and there's no reason to assume they rotate the same speed or direction. However, if the core changes the speed or direction of it's rotation significantly (some interpretations of the magnetic field changing direction requires this), the planet as a whole will still have to conserve angular momentum, so the crust could be expected to change the speed or direction of its rotation. While the change would only be fast in geological terms, the poles don't have to move much for life to get interesting.

But, of course, we have very little data about the core, so we are left with making computer models which account for the magnetic field changes and guessing which one might have the accurate underlying assumptions.