Antarctic Ozone Hole Leveling Off

twistedfuck writes: "An Irish Time article reports that the size of the hole in the antartican ozone layer is levelling off and should begin reducing in size. It seems like it should be welcome news but it is tempered by the fact that more UV radiation will reach the southern hemisphere this year because the hole will persist longer. Unfortunately I can not find any details regarding the NOAA report on their website." Update: 11/06 17:31 GMT by H :Thanks to Isaac Lewis, NOAA Sysadmin and Slashdot reader, for pointing out more information, as well as pointing out the ozonelayer site.

Comments

Hooray for regulation?

[bonzoesc]

Are we to believe that this reduction in size is a result of global regulation of CFCs, or could it possibly just be part of a natural cycle? Too bad we didn't get satellites before styrofoam.

Re:Hooray for regulation?

[legoboy]

No, but it is what the preponderance of the evidence suggests.

a) Upon seeing problems, we've heavily cut back on all sorts of emissions under the belief that it will fix the problem.
b) Results of a) (above) will take sixty more years to manifest.
c) Problem is disappearing long before results of a) are known.

Therefore, perhaps a) was a faulty assumption that costs businesses billions annually, and the ozone hole is really just a cyclical thing?

That said, lower emissions are good, if only for two reasons - one, so that whilst canoeing the Indian Arm of the Fraser River, I don't know that Vancouver is (that way) due to the brown sky. Two, because they *do* seem to be responsible for all sorts of human respiratory problems. You know, if environmentalists weren't all a bunch of crackpots who use pseudoscience to justify whatever their jihad of the day is, I'd probably identify myself as one.

PS - The ICE at the NORTH POLE is MELTING!!! Oh NO!!! ... Oh wait, that happens all the time?

Mother Nature

[rockwood]

IMHO Mother Nature takes care of herself. Fires to clean the earth, wind to sweep away the garbage, seasons to refresh the vibrance of life and so forth...

This article suggests that though the total mass of the hole is reducing in size, it is also maintaining itself for longer periods. Without research, an immediate assumption would suggest that this would be letting the same doses of UV rays reach the earth annually.

I'd say Mother Nature is attemtping to counteract our efforts and regulate the earth the way she has done for millions of years!

And given our (human) track record.. I'd give 1000:1 odds in favor of Mother Nature doing the right thing.

Re:Mother Nature

[NecroPuppy]

*sigh*

The increase of UV radition getting to the earth due to the depletion of ozone is smaller than the error factor of the best detection instraments.

And, even if it weren't, even changes as high as 20% aren't abnormal in nature. Otherwise, there wouldn't be life in Florida...

Big Deal...

[Anonymous Coward]

Who Cares? This only affects those of us that
actually go outside, and in all honestly, how many of us have actually been outside in the
past two weeks. (Outdoor-type quake mods do not count)

mccann@telalink.net

Additional info at EPA site

[cats-paw]

I was just looking into this not too long ago. Strangely enough, we met someone from Israel while we were travelling in New Zealand who said it had closed, which I was sure was wrong. Turns out it's still there.

And remember it's not really a hole, i.e. there is ozone present, it's just at significantly lower levels.

Here are a couple of sites I found useful :

www.epa.gov/ozone/science/hole/holehome.html
www.atm.ch.cam.ac.uk/tour/

When we were in New Zealand the sun feels different ! It feels very intense and somewhat uncomfortable, and it was only the first month of spring. You HAVE to use sunscreen.

Problem with Environmental Theories

[Moridineas]

The problem with environmental theories is that they are just that...theories.

Much like chemistry of 50 or 100 years ago in many ways would seem laughable to what we know now (and will again in 50 years probably), the science of the environment is a young and new science. Unlike chemistry or physics, it's much harder to do experiments, and the timescales involved are immense.

The truth is we simply know too little about the Earth to make longterm models and whatnot that are dead on. We can make GUESSES, and maybe even good guesses, but there is still so much that we don't know at this point.

As a side note-it is my understanding that CO2 levels during the time of the dinosaurs were much higher than they are today. The Earth can handle huge changes with relatively little environmental impact. It's been around (what? 5 billion years?) a long time, I don't think humanity can destroy it in a little over two century.

Scott

Re:Problem with Environmental Theories

[mrwilsox]

You're right, we're not going to destroy the earth in a little over two centuries. However, we are making great strides toward making the earth very, very hard to inhabit for humans (and a number of other critters). If we just let things keep on going as they are and use up all of our fossil fuels and spew pollution into the air, land, and sea, the earth won't be a great place to live for us. But you better believe Mother Nature wouldn't care one bit if humans disappeared forever. Earth itself would keep on living, with other species remaining and probably a lot happier that we're gone.

Re:Problem with Environmental Theories

[CaptainCarrot]

As a side note-it is my understanding that CO2 levels during the time of the dinosaurs were much higher than they are today. The Earth can handle huge changes with relatively little environmental impact.

Actually, the environment at the time of the dinosaurs was hugely different. Earth had no polar ice caps, and the continents were arranged differently. In the dinosarus' heyday around the middle of the Jurassic, the Atlantic Ocean didn't exist. The bulk of the land was grouped into an enormous crescent surrounding what is now the Indian Ocean. The coasts were warm and humid; the continental interior was desert. It was a world utterly unlike that we live in today, and we probably could not have flourished in it.

Re:Problem with Environmental Theories

[Jormundgard]

Environmental science is over 100 years old, but it didn't start to thrive until after WWII.

The ozone hole and CFC sitatuion is one of the most well understood things in science however. It's due to the following:

• Companies used to produce CFCs - a combination of Chlorine, Fluorine, and stuff that is extremely resilient. Most importantly, it's resilient to radiation, so it can survive long distances. Note that some people try to compare this to the chlorine dumped by Mt. St. Helens - but free chlorine is easily busted apart by radiation, while CFCs can survive the trip ahead of it.
• The Equatorial Winds are a series of currents that blow from the equator to the poles (with a slight lean towards the north(?) ) - these blow chemicals form the equator (where humans mainly live) to the poles. Chlorine molecules are destroyed in the upper atmosphere by radiation, but CFC's survive the trip.
• Finally, at the poles, the CFCs (which take a while to decay) break up in appreciable amounts at the poles, where the free chlorine reacts with the ozone, and breaking it apart. The fact that there are free fluorine atoms in the poles, which is only possible by man-made actions, is the smoking gun.
• 
  Based on the equatorial cycle, one would expect to be free of CFC effects after about 100 years - I guess it's been about 25? So I guess this is about when one would start to notice the effects.
  
  Although there are the occasional puppets who still denounce ozone problems, the industries and governments were immediately convinced by the evidence, which is why humans have probably fought off this problem.
  
  Finally, the CO2 issue is a global warming thing, which isn't really related to the ozone hole problem. That's a polar icecap melting problem, and the data is still not totally convincing---the problem is that some predictions say that it's too late to prevent a 1m rise in sea level.

Re:Problem with Environmental Theories

[Stelmsind]

Which volcano in the Phillipines poured out CFCs? I'd be very interested in hearing about a volcano that poured out chemicals that do not naturally occur! CFCs are manmade - they are no naturally occuring CFCs.

The hazards we now associate with CFCs were discovered in the 1960s when a British chemist (Lovelock) was interested in tracing the motions of air masses. He was using CFC's to do so, as they were ideal for tracing air motions, being chemically stable and not naturally-occurring (they are only man-made) so their presence in an air mass could not be confused with CFC's coming from natural sources.

Perhaps you are thinking of the theory that volcanic chlorine caused ozone depletion? There are a number of problems with this:

(1) There was significant O3 loss in the 1980's, but no major volcanic activity then.

(2) There has been major volcanic activity since O3 monitoring began in the 1950's, but it was not necessarily associated with declines in O3. That is, O3 losses and volcanic activity appear to be uncoupled in time (lack temporal consistency)

(3) Measures of hydrogen chloride in the stratosphere after the relatively recent eruptions of Mt. Pinatubo and El Chicon showed less than a 10% increase in stratospheric HCl following those eruptions, while stratospheric HCl has increased steadily across recent years. Furthermore, it is estimated that 1% of the Cl released by the eruption of Mt. Pinatubo Cl made it to the stratosphere, judged by the increase in HCl in the stratosphere following the eruption and the estimated release of Cl by the volcano.

(4) Stratospheric hydrogen fluoride has also increased steadily in parallel with HCl, as would be consistent with CFC sources.

(5) Much of the HCl produced by volcanoes (or Cl from sea salt) is injected into the troposphere and very little of that makes it to the stratosphere, as it is washed out first. Volcanic emissions include abundant water vapor, and HCl and NaCl are quite soluble in water, while CFC's are not.

(6) Most of the HCl that does make it to the stratosphere is rapidly washed out -- that is the major removal mechanism for Cl from the stratosphere.

(7) After volcanic eruptions, scientists find enriched sulfate in ice caps, suggesting that the eruptions inject sulfate into the stratosphere, where it gets widely distributed before being washed out. However, ice caps are not enriched with Cl following volcanic eruptions, suggesting that most Cl doesn't make it to the stratosphere where it could get dispersed as sulfate does.

Great, that's what G.W.Bush needs to hear =)

[veddermatic]

"See, fuck the environment, it just fixes itself! That Alaskan Wildlife thingie my dad and Uncle Cheney say I should let thier companies drill in will be all wildlifey again in no time!"

Oh well. Luckily the world will end AFTER I'm dead.

Press Release

[ukryule]

is at http://www.publicaffairs.noaa.gov/releases2001/oct 01/noaa01104.html.

To summarise the findings, it seems the density of Chlorine from CFCs has peaked, and it is expected the Ozone hole will gradually (i.e. over the next 50 years!) disappear.

It now seems to be an interesting case of us screwing up our environment, working out what we'd done, and fixing it. However, you could consider that we just 'got lucky':

• The fact that it was concentrated in one spot meant that the problem was identified before we'd managed to strip the whole atmosphere of ozone.
• It was concentrated over the least populated part of the globe. Compare the increase in awareness/incidence of skin cancer in Australia/New Zealand with what might have happened if it was concentrated around the equator.
• The solution (banning CFCs) had relatively little economic impact making it easily implementable. It was also a universally accepted solution.

Compare this with the current situation re global warming, and this looks less like a successful victory and more like a warning shot across the bows ...

Re:Press Release

[frankie]

I read a nice article (not sure if was on slashdot)

Danger! Danger, Will Robinson! Moderators, please do not Not NOT mark a comment "Informative" if it makes a scientific claim without providing any hard links to back it up.

A quick google search, for example, led me to several potentially informative web sites, such as:

• European Chlorine industry association
• American Chlorine industry association
• an anti-Chlorine lobbying group
• Women's Environmental Network

etc, etc, etc. Don't just spout off random crap that you think you heard once.

Google means never having to say "I don't remember".

Re:Size will decline?

[dragons_flight]

Sunlight naturally converts some oxygen to ozone in the upper atmosphere. Problem is that when CFCs and other chemicals are present, they eat up ozone far faster than it is typically produced.

Ozone is harder to produce and easier to break down when it is cold, which is one reason ozone is at its lowest levels over the poles in winter (also when there is a deficit of sunlight). The poles are also especially vulnerable because global wind patterns circle around them rather then refreshing the air. Even the most stubborn air pollutants will break down or become absorbed by the environment if we stop pumping them out and give the Earth time to get back to normal.

The Polar Vortex, that's why it's there

[dido]

I believe there's a meteorological phenomenon called the polar vortex that causes the ozone hole to occur at the South Pole and during Antarctic summer. See this link for more details. Short version is, during polar night there's a huge whirlpool of cold air that circulates there all night causing the CFC's we've emitted to more rapidly destroy the ozone in the region. By summer, the vortex stops, so the ozone hole disperses. There's also a vortex in the North Pole, but because there are a lot of irregular land masses there, the vortex up north is a lot weaker, hence the ozone hole up north is far smaller. But global warming is causing the northern vortex to strengthen, and hence increase the size of the hole up north.

This is what I get for watching too much Discovery Channel!

Ozone hole leveled off every year

[LazyDawg]

Ok, here's the deal:

Stratospheric ozone is created by bombarding normal, happily breathable O2 mollecules with ultraviolet light, splitting the O2 into a pair of O1's. These O1's eventually bump into another O2 mollecule and create O3. Big woop.

Where there is solar UV light, you'll probably see some ozone popping up. Since the Antarctic Desert is in the dark for a good chunk of the year, you'll discover a not-too-surprising lack in stratospheric ozone over winter and well into the Spring. Also not surprisingly, we have an ozone hole over the north pole.

Over the north pole, of course, there isn't quite as extreme a desert as over the south, and there are more large land masses nearby to carry air better.

Back in the 30s when the first weather measurements were taken in Antarctica they found almost identical levels of UV light hitting them as during a modern winter. Greenies prefer to depend on climactic models rather than empirical evidence these days, however, so their multi-million dollar research is stating the problem is getting bigger, even if someone else's multi-thousand dollar research is saying the opposite.

The ozone hole is the result of too many people putting faith in government, who can't predict the future more than a few weeks down the road, and weather men, who can't predict the future more than a few days down the road, and expecting their government-funded computer models to be able to predict the future years down the road.

Good point

[Uttles]

I agree with your statements, and I've read similar articles in scientific periodicles. Those articles, however, are usually well hidden and no longer than half a page, because they aren't very popular. So why is rational thought about the O-zone not popular? Well it's not sensationalist, it doesn't give people something to "fight" for, and people who are "environmentally concious" just hate to admit that they are wrong.

Another thing that I don't think you touched on, our climate goes in cycles. I don't recall the exact dates, but I know that some time ago in recent history (1960's maybe?) all of the popular scientists were warning of global cooling. That's right, the earth was getting too cold and there was going to be another ice age if people didn't do something about it. Our climate is not as stable as some would imagine, and contrary to popular beleive we humans have nothing to do with it. Yes, in large cities there is smog, but that is a microclimate just around the city, and it dissipates in the atmosphere and goes away eventually, doesn't affect the global environment. The global climate is something that is very dynamic and not easily understandable. One thing is for certain though: there is no proof that we have a problem with the O-zone layer.