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NASA Announces Record Ozone Hole

Drewsk writes "NASA has announced that the ozone hole over the Antarctic has broken all records. From the story: 'From September 21 to 30, the average area of the ozone hole was the largest ever observed, at 10.6 million square miles,' said Paul Newman, atmospheric scientist at NASA's Goddard Space Flight Center, Greenbelt, Md. If the stratospheric weather conditions had been normal, the ozone hole would be expected to reach a size of about 8.9 to 9.3 million square miles, about the surface area of North America.""

45 of 190 comments (clear)

  1. Re:Was Wondering... by i+kan+reed · · Score: 4, Interesting

    It had shrunk, up until this time, I was under the (obviously mistaken) impression that it had stayed shrunk.

    I'm not a big jumping to conclusions kind of person, but there are signifigant environmental impacts on the creation of new upper atmospheric ozone as well. I think, although I could be wrong, that most atmospheric ozone is created by lightning causing chemical reactions. There could be some relationship there that's gone unaddressed. Regardless, this is hardly good news to hear.

  2. I read about this by vought · · Score: 2, Interesting

    four days ago.

    Besides all the technical trinkets, is this where science ends up on Slashdot?

    Pretty sad, if you ask me - game consoles and .mp3 players get higher billing than planetary changes - on the planet we live on?

    1. Re:I read about this by tehSpork · · Score: 2, Insightful

      Meh, MP3 players and consoles come and go with a rapid speed that requires many news posts to keep track of. I haven't seen a Planet 2.0 with new and improved mineral deposits slated for release yet, my guess is that the project went overbudget and got cancled. :)

    2. Re:I read about this by Anonymous Coward · · Score: 3, Insightful
      Pretty sad, if you ask me - game consoles and .mp3 players get higher billing than planetary changes - on the planet we live on?


      It's because these global warming news are super depressing, anti-american, pro-terrorism and bad for the economy. We should collectively hush-hush these fairy-tales of evident destruction of human kind and just live in four year periods. Now, go back reading console news and smile. Remember - ignorance is strength!

    3. Re:I read about this by Anonymous Coward · · Score: 4, Funny

      I for one, am looking forward to our improved sun tanning opportunities. UV kills parasites too. It's win-win here. Ozone layers are over-rated.

  3. Sometimes... by God+of+Lemmings · · Score: 2, Interesting

    Sometimes I wonder whether or not the ozone hole has always been there and we just noticed the hole one day and thought it was something special. I mean, the Earth is slightly egg shaped, doesn't it kind of make sense for the atmosphere to also not be spherical?

    --
    Non sequitur: Your facts are uncoordinated.
    1. Re:Sometimes... by vxvxvxvx · · Score: 2, Insightful

      Sure! Your intuition is far more powerful than 100 years of scien-ma-tific observation. Well, admittedly science wasn't exactly at the same level in 1906 as it is today, especially for things like upper atmosphere composition.

    2. Re:Sometimes... by Zorque · · Score: 2, Funny

      And your fart joke certainly isn't of 8th grade calibur.

    3. Re:Sometimes... by antifoidulus · · Score: 4, Funny

      Dude, if your farts have a "shape" I would recommend some pepto bismol......

    4. Re:Sometimes... by kfg · · Score: 5, Informative

      Sure! Your intuition is far more powerful than 100 years of scien-ma-tific observation.

      Although the presence of ozone in the atmosphere has been known for a bit over 100 years, knowledge of the presence of a permanent ozone layer is rather more recent. Man did not reach the south pole until 1912 and did not fly over it until 1929. The first permanent observation station at the south pole was not established until 1957. Meanwhile the ability measure the thickness of the ozone layer, from either ground or satellite is concurrent with the discovery of the ozone hole. Mid 70s through mid 80s. Although ballons have been flying into the stratosphere for a couple ticks over 100 years, we only got a good idea of its structure in the mid 80s when we sent up an instrumented U2. OP is right to the extent that we really know squat all about the history of the ozone layer.

      Go back to eighth grade science class, then come back and post on slashdot.

      I had just finished my undergraduate studies in physics when we first started acurately measuring the thickness of the ozone layer indirectly; and thus being able actually map it. Perhaps you have the advantage on me of only recently being out of the eighth grade.

      KFG

  4. The hole got bigger? by Warbringer87 · · Score: 4, Funny

    Doesn't that usually happen when you fuck with a hole?

  5. Re:Damned if you do..... by wasted · · Score: 3, Interesting
    So if it's warmer, the ozone hole gets BETTER? It's global warming man!


    If I remember correctly...

    Ozone is created by lightning from thunderstorms.

    The warmer the surface, in general, the more likely it is that thunderstorms will occur.

    Antarctica is the coldest place on earth, therefore it is less likely that thunderstorms will occur in Antarctica, and less ozone will be produced in that area.

    Consequently, we can assume that global warming would reduce the size of the ozone hole if that warming could be focused on Antarctica, or was at least proportional.

    If anyone knows more than I on this, (yes, I am an old weather forecaster, but if you are sure of your data,) please correct me.
  6. Wow, that Paul Newman by jeffkjo1 · · Score: 5, Funny

    said Paul Newman, atmospheric scientist at NASA's Goddard Space Flight Center, Greenbelt, Md.

    Is nothing enough for Paul Newman? It's not enough that he stars in movies with Robert Redford, or that I'm forced to by his Salad Dressings and Microwave Pop-Corn... now I must apparently take his word on the o-zone layer. I suppose in 20 years he'll show up in a computer animated film as some sort of washed-up radio telescope convinced to go for one more shot at the big time.

    /end sarcasm sequencer

  7. Re:Great by PhB95 · · Score: 2, Insightful

    I heard when all this started that CFC made its way to upper atmosphere in a matter of 2-3 decades. So if dropping CFC helps, it may only become visible in the next decade... But I can't help thinking you may be right here :-)

    --
    One of those Europeans...
  8. Re:Was Wondering... by omegashenron · · Score: 4, Informative

    The article states the following:
    "these ozone-depleting substances typically have very long lifetimes in the atmosphere (more than 40 years).

    Obsoleting Freon has helped, however it will take tens of years for the existing CFC/HFC/HCFC's etc gas levels to drop to acceptable concentrations.

    --
    Excuses Are Like Assholes - Everybody's Got One
  9. Re:Great by Apparissus · · Score: 5, Informative

    RTFA. It kindly mentions that

    A) Chlorine, Bromine, and their Ozone cappin' friends stay in the atmosphere for decades. Even with a significant drop in emissions (its precipitousness is reminiscent of the bunny slope) it will be a very long time before significant positive effects accrue. As the article points out, we can expect about 0.1% to 0.2% per year in the near term.

    B) This record breaking event is the culmination of several phenomena, including large-scale, seasonal factors that completely overshadow the tiny bit of healing the layer has done in the last few years. "This slow decrease is masked by large year-to-year variations caused by Antarctic stratosphere weather fluctuations."

    One thing the article does NOT mention is any cry of "Wolf!". There isn't any environmentalist finger-wagging, just some scientists saying "holy shnikes, take a look at the SIZE of that thing!!"

  10. Re:Damned if you do..... by thre5her · · Score: 3, Interesting

    According to Al Gore, a rise of 1 degree at the equator would mean a rise in 12 degrees at the poles. So, it seems that yes, global warming would foster the creation of ozone closer the poles. However, I don't think anyone wants to see more ice shelf fall into the oceans and turning Europe into a giant ice cube.

  11. Where the ozone comes from by Beryllium+Sphere(tm) · · Score: 5, Informative

    The ozone we're concerned about here is formed by solar ultraviolet in the stratosphere. Almost all thunderstorm activity is in the troposphere. The ozone that thunderstorms and photochemical smog produce only lasts a few weeks.

    Now, if you want to get confused, CFCs are both catalysts of ozone breakdown and greenhouse gases. To make you even more confused, upper tropospheric ozone is a greenhouse gas, not as important as CO2 but worth taking into account.

  12. Re:Damned if you do..... by Andrew+Kismet · · Score: 5, Interesting

    Something repeatedly bothers me. We act like global warming caused by humans means the end of days, but surely the earth has undergone far more cataclysmic changes (such as after supervolcanoes), even during the lifespan of humanity, and we've lived to tell the tale?
    Perhaps it's just now that we're so widely knowledgeable (if not intelligent) about our world at large, we realise just how many people will be outright fucked over by the coming changes. I'm sure humanity will survive, regardless of what happens. Anyone recall Daisyworld and biodiversity versus adverse conditions from biology class?

  13. Hmm.... by Lars512 · · Score: 4, Funny

    ...increased cancer for us Australians this year. Not to worry though, in 60 years, whatever skin we have left on our face and arms after the melanomas have been removed will be safe(r).

  14. Re:Damned if you do..... by beckerist · · Score: 3, Funny

    holy crap, but the fact he just used Al Gore as a reference doesn't bother you?

  15. Re:Damned if you do..... by pluther · · Score: 5, Insightful
    We act like global warming caused by humans means the end of days, but surely the earth has undergone far more cataclysmic changes (such as after supervolcanoes), even during the lifespan of humanity, and we've lived to tell the tale?

    Some of us have, anyway.

    Sure, the earth has seen some big cataclysms in the past, which haven't wiped out all life on the planet. The big ass meteor that made the Yucatan peninsula 65 million years ago only wiped out about 90% of all species.

    But even within, as you say, the lifespan of humanity, there've been some major catastrophes, that haven't wiped us out. A couple of ice ages, we weathered through (so to speak). And even more recently, plagues, war, famine, huge volcanic eruptions. Sure the human species have survived. Villages, towns, cities, nations, even entire civilizations have been wiped out, but humans survive.

    Mostly, I just don't want to be part of one of the civilizations that gets wiped out.

    The same can be said about population pressure. The more people there are, the greater the chance some big disease will come along to take care of the problem, or some asshole pushes the button and nukes us back to the stoneage. Either way, nature will adjust. She's just not as picky as I'd like about her methods.

    --
    If the masses can keep you down, you're not the Ubermensch.
  16. It never went away by astro-g · · Score: 5, Informative

    certainly not for those of us who have to live under it.

    I live in New Zealand, the current position and shape of the ozone hole is a regular feature of TV weather reports.

  17. NASA announcement raises questions... by the_tsi · · Score: 4, Funny

    "NASA Announces Record Ozone Hole"

    - Yes, but will it be available in retail before the holiday shopping season? What will availability be?

    - Can it run Lunix? Duke Nukem 4? NetBSD? Can I make a beowulf out of them?

    - Shouldn't we wait for Rev. B?

    - Why didn't they mention any pricing in the article? It's totally a vaporware mock-up, like that keyboard!

    - Did they use clean energy to manufacture it?

    - Isn't the one from RKA/ESA/JAXA superior? NASA only makes hoaxes anyway -- Was this "ozone hole" actually on a sound stage in Nevada?

  18. Re:Was Wondering... by Anonymous Coward · · Score: 5, Informative
    Confusingly, an interviewed scientist was also commenting that people shouldn't panic, because it was on a downward trend and was still expected to heal itself over the next so many decades. I'm not quite sure exactly what was meant, because under most circumstances I wouldn't intuitively consider a "largest ever recorded value" to play any part in a measured downward trend.

    There are two possibilities that don't defy logic:
    • The depletion of the ozone is increasing but the rate of increase is decreasing. Logically there will eventually be a point at which the depletion rate reaches a zero value and then goes negative resulting in a regeneration of the ozone layer.
    • The record size hole was a statistical anomaly in data that showed that over a period of many years that the ozone layer is rebuilding. As long as the value of the statistical anomaly doesn't fall further than say 2.5 times the standard deviation from the curve fit, then it could have been just due to random error. And if it wasn't then the error would be systematic error but could probably be explained by changing climate conditions (such as Antarctica being colder than normal).
  19. Re:Was Wondering... by Anonymous Coward · · Score: 2, Informative

    The real problem is a hundred years of devices using freon rotting in dumps worldwide. There were projections of it rising for a number of decades before it started to drop perminately. Actual recovery will take a couple of hundred years. Recycling of the devices would help but most of the world isn't willing to spend the money and even the US has a poor record for recyling old refridgerators and such. Just imagine all the millions of rusting cars leaking freon from old AC units. Most refridgerators in this country don't use freon but there's still some older ones in service and oceans of them in dumps. Add to that old paint spray cans and hair spray cans. Look on the brightside how bad would it have been if we hadn't stopped? Australia and New Zealand might have been covered by the hole by now. I spent some time in New Zealand a half a dozen years ago and skin cancer was common there. People didn't tan they burned. Better to start recovery now than waiting there is no ozone layer and everyone is getting skin cancer. When I was growing up I had never heard of skin cancer. Now I'm one of the few people I know over forty that hasn't had it and I know people in their twenties that have had skin cancer. Teens and children are getting it. It's one of the great unspoken plagues.

  20. Statistics by agentcdog · · Score: 5, Interesting

    I am a scientist trained at the undergraduate level (so I claim no authority). They beat statistics into us. I now read things with my statistical-skeptic hat on. Here's my problem: .2% decline only matters if there is a margin of error that is small enough for .2% to be significant. Let us say, for argument's sake, that the error in our readings is around 3%. We then model the system and have check it against the data that we have. Is there any way for us to have enough data to make the statement that we expect a .2% improvement? Statistics come with confidences. I'd be shocked if the confidence level on this data is above 50%. Does anyone have any insight here?

    --
    If I understand Dirac correctly, his meaning is this: there is no God, and Dirac is his Prophet. -Pauli
  21. Re:Damned if you do..... by Chas · · Score: 4, Insightful

    "She's just not as picky as I'd like about her methods."

    The problem is, when most people say this, by "discerning" or "picky", they automatically assume that THEY would be part of the population favored by such choice...

    --


    Chas - The one, the only.
    THANK GOD!!!
  22. Re:Your questions answered by jez9999 · · Score: 2, Informative

    http://en.wikipedia.org/wiki/Ozone_depletion#CFCs_ in_the_atmosphere, and the text below that section, seem to call bullshit on your assertion that CFCs have no effect on the ozone.

  23. Re:Damned if you do..... by Da+Fokka · · Score: 5, Insightful

    Something repeatedly bothers me. We act like global warming caused by humans means the end of days, but surely the earth has undergone far more cataclysmic changes (such as after supervolcanoes), even during the lifespan of humanity, and we've lived to tell the tale?


    Oh yes, we have survived. But barely. According to the Toba Catastrophe Theory the Lake Toba eruption reduced the total number of human beings to 1000-10000. We also survived the plague, which killed of a third of Europe's population in the middle ages.

    But surviving doesn't mean a walk in the park. Yes. We would survive sea levels rising a couple of feet. I live in Holland and we've been fighting the water for centuries. Now, we're more prosperous than ever so we'll be able to build the dykes. But countries like Bangladesh (which floods like every two years already) would be in serious trouble and would not be able to do a thing about it.

    Perhaps it's just now that we're so widely knowledgeable (if not intelligent) about our world at large, we realise just how many people will be outright fucked over by the coming changes. I'm sure humanity will survive, regardless of what happens. Anyone recall Daisyworld and biodiversity versus adverse conditions from biology class?



    You are right if bare survival is your criterium of success. But I'd prefer to aim a little higher than that.

    Oh and of course I am aware that I'm talking about global warming, which has very little to do with the hole in the ozone layer. But the point remains valid.

  24. Re:Your questions answered by Anonymous Coward · · Score: 5, Informative

    no-one has ever explained how CFC molecules which are much heavier than air, can rise up in the stratosphere, travel all of the way to Antarctica before being broken down into chlorine and fluorine and reacting the O3

    Maybe not, but they're there. All the same tools that tell us whats in other planets' atmospheres works equally well on our own. Further more, as surprising as it may be, if you lay down on the ground, you're not likely to asphyxiate unless someone dumps a sufficient amount of a heavy gas right next to you, since the atmosphere mixes up rather easily. As for how they move, I'm going to suggest things like the Jet Stream for moving them around the planet, and equatorial heating to carry CFCs into the upper atmosphere and down towards the pole.

    Chlorine in the ice

    Interesting theory. Where did the chlorine come from? A molecule of Cl2 (total atomic mass 71) is more massive than N2 (28), O2 (32), and CO2 (44), or does "too heavy" only count when it's you saying it? Could it possibly be that the Cl in your ice is the same Cl in CFCs?

    thus turning your refrigerator into a potential BOMB.

    Aside from someone else already pointing out that it's not benzene, I guess you're too young to remember the days of early ammonia refrigerators, now those were the BOMB!

  25. Finally! by SilentOneNCW · · Score: 2, Funny

    Alright everyone, our goal has been achieved. Take a little break and we'll meet back here for more ozone depletion in a few aeons, mm'kay?

  26. Re: Ozone Hole by Anonymous Coward · · Score: 5, Interesting

    I don't think the severity of the Ozone hole, regardless of its fundermental underlying causes, can really be accepted or apprecciated by any-one living in the Northern Hemisphere. Its appears to be something akin to "Ah well, that sound bads, nevermind" BUT .. Anyone living in Australia or especially New Zealand, the coutries on the edge of the hole, know too well what it will mean for them this summer...and it not pretty.

    With the highest rates of melanoma skin cancer in the world due to the lack of UV protecting Ozone and predominantly clean air. These two countries bear the full brunt of the impact of the hole. At the height of summer, sunburn can occur in as little as 6 minutes!! of sun exposur. Anyone outside without SPF30+ sunscreen, glasses, a shirt and a hat should be considered a fool. This is what its like to live with a hole in the Ozone above your country.

    If this is what is was like above your country in summer, when you would just like to enjoy yourself and "Catch some rays, down at the beach". You certainly wouldn't be arguing about how it was cause or who caused it, you'rd be trying to find a way to fix it!

    Sometimes, I wish the hole could be moved to somewhere move deserving.

  27. Re:Damned if you do..... by Orp · · Score: 4, Informative

    My God where did you get your meteorology degree?

    Tropospheric ozone is created by many things but is very reactive and does not last long. Lightning does produce ozone in the troposphere as does certain chemical reactions between anthropogenic pollutants.

    Stratospheric ozone is created when high-energy ultraviolet light from the sun splits diatomic oxygen (O2) into oxygen atoms (O) which can combine with O2 to create O3. UV also splits O3 into O and O2, and there is constant creation/destruction of O3 in the strasophere. It reaches an eqilibrium which is a function of a bunch of things, but the end result is (a) the creation/destruction of O3 in the stratosphere "absorbs" the most energetic UV from the sun (which is good for life) and (b) this process heats up the stratosphere, making it one big inversion which has the nice side-effect of keeping thunderstorm updrafts from blasting into the mesosphere.

    In order to undertsand why there is an ozone "hole" over Antarcitca you have to understand about the dynamics of the atmosphere. Most ozone is actually created in the tropical latitudes and is advected southward/northward via the Hadley Cell circulation. The polar vortex over Antarctica tends to inhibit mixing across its boundary, so stuff that gets in it tends to stay there. Ozone depletion due to CFCs tends to be greatest around this time of year when the Antarctic is entering Spring and the sun is beginning to interact with polar stratospheric clouds which are a major catalyst to the ozone depletion.

    Anyone could look this stuff up in a recent undergraduate meteorology textbook. Just about all of the "Mod 5 : informative" posts in this thread are laughingly incorrect.

    Same goes to the douche who thinks "CFCs are too heavy to get into the Stratosphere". I'm not going to bother to explain that one to you.

    And finally, don't ever mention "global warming" and "ozone hole" in the same sentence as if they are related. They are not.

    --
    A squid eating dough in a polyethylene bag is fast and bulbous, got me?
  28. Re:Your questions answered by hey! · · Score: 2, Interesting

    a) the temperature above Antarctica has fallen in the last fifty years (and not a single climate model predicted that one) and in the ice clouds that form high in the stratosphere in the early Antarctic spring the temperature drops below -80C. Chlorine in the ice reacts with the ozone.

    But but by your argument there should not be any stratospheric ice, since water is heavier than atmospheric gases.

    In fact, if we accept your theory then we wouldn't be able to breathe at sea level, because atmospheric CO2 would sort to the bottom, forming a thin layer of pure CO2,over which there would be thick layer of pure O2, over which there would be a very thick layer of N2.

    However, below 100km, the weight of gas molecules is completely irrelevant to their atmospheric concentration due to many, many mechanisms that mix the atmosphere.

    --
    Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
  29. Re:Was Wondering... by RockModeNick · · Score: 4, Interesting

    Freon is much more dense than air. Rotting devices in landfills are not getting CFC's into the upper atmosphere. I'd look to substances with significantly more potential to end up there, like jet fuel burnoff, as being the source of ozone troubles.

  30. Re:900 million cows for mcdonalds is part of the s by Dunbal · · Score: 2, Insightful

    and how much shit those cows make and how much they fart methane!!!

          You know, people fart too. I hope you're wearing your butt-plug, my fellow eco-warrior...

    --
    Seven puppies were harmed during the making of this post.
  31. This is perfectly normal by TheVelvetFlamebait · · Score: 3, Informative

    Here's a brief explanation:

    CFCs need to leech from the troposphere to the stratosphere. The troposphere is very easy to travel through, as temperatures decreases as you approach the stratosphere. This allows for the warmer air near ground level to rise to the top of the troposphere, where it cools and sinks back to the ground (which then warms again, etc). This makes sure that pollutants such as CFCs travel very well throughout the troposphere.

    However, the stratosphere warms as you go higher. The cooler air down below sinks back into the troposphere, making it hard for pollutants to enter it. The stratosphere is where the ozone is. The only way for the gas to get into the stratosphere is to diffuse very slowly into it, where it can do its damage.

    This is why there is such a big hole now. Diffusion into the stratosphere takes many years. Scientists have predicted a peak in CFC levels in the stratosphere around about now. Slowly, all the CFCs we've produced will diffuse, react to become relatively harmless free radicals, and the ozone layer will be restored. Until then, sit tight.

    --
    You know, there is a difference between trolling and pointing out the flaws in your reasoning. Just saying.
  32. It is a user contributed site by everphilski · · Score: 2, Insightful

    Why didn't you contribute this article 4 days ago, then?

  33. I wrote a journal entry on this topic yesterday by maynard · · Score: 2, Interesting

    link

    It contains contextual information about what is ozone, who the main players are / were that contributed to the ozone cycle discovery, who first discovered the Antarctic ozone hole, and why it is believed that it will begin to shrink in the near future (decades).

    Hope it is of interest.

  34. Re:Damned if you do..... by Orp · · Score: 5, Informative

    Same goes to the douche who thinks "CFCs are too heavy to get into the Stratosphere". I'm not going to bother to explain that one to you.

    Actually, I'd really like to hear an explanation. I'm not going to claim to know anything about CFC's, but if these gases really are heavier than air and don't readily mix with air, how exactly does a bucket of them in my back yard elevate itself to the upper atmosphere?

    Think of it this way: What is "air" in the first place? To a good approximation within the troposphere, it's a mixture of molecular oxygen (molecular weight = 32 grams/mol, 21%), molecular nitrogen (MW = 28 g/mol, 78%) and argon (MW = 40 g/mol, .9%). If the heaviest gases simply sunk to the bottom, we would be suffocated by argon near the ground and all of the nitrogen would be on the top of the atmosphere, with the oxygen in the middle.

    The troposphere (tropos in Latin means "turning" or "mixing") is well-mixed and the relative ratio of the three aforementioned permanent gaes to one another is constant. If you introduce a heavier gas (higher MW) it will still get mixed into the lighter gases over time due to the winds. Brownian motion will also cause heavier gases to diffuse in a calm environment.

    CFCs will spread laterally across the globe by the horizontal winds. Whenever there is a strong thunderstorm, updrafts will slam air, which originates near the ground, into the tropopause, the boundary between the troposphere and the stratosphere. Very strong updrafts can intrude into the bottom of the stratosphere where the tropospheric air mixes into the stratosphere. Once something gets into the stratosphere (if it's got a very small terminal velocity - think about strong volcanoes spewing ash) it tends to stick around because the stability of the stratosphere is so high (due to the temperature inversion I mentioned before).

    Back to "heavier gases" for a moment. It is true that if you "pour" a heavy gas onto the ground it will spread out before mixing. There have been cases where CO2 (MW = 34) has seeped out of the ground and spread laterally, suffocating people (google Lake Nyos). But given a few hours of typical winds, the heavier gas will be diluted and over time mixes into the rest of the atmosphere, contributing slightly towards the atmosphere's own average molecular weight.

    --
    A squid eating dough in a polyethylene bag is fast and bulbous, got me?
  35. Re:Was Wondering... by Keebler71 · · Score: 2, Insightful
    Not long ago I was wondering, "whatever happened to the ozone hole?" It seemed that Global Warming had taken over as the looming apocalypse. So the obsoleting of Freon hasn't helped?

    Remember how this was supposed to be a global-warming induced horrible hurricane season?

    --
    "It takes considerable knowledge just to realize the extent of your own ignorance." - Thomas Sowell
  36. Re:Was Wondering... by letxa2000 · · Score: 2, Informative
    For the geeks out there who haven't studied Archemedes Principal, that 5.5 times heavier than air coupled with the fact that it doesn't mix with air, produces the same effect when CFC's are dropped into the atmosphere as dropping a solid steel cannon ball into a lake. Since there are noted to be no large collections of cannon balls floating on lakes the obvious conclusion here is that CFC's are highly unlikely to float up to the high atmosphere and cause any problems. They can't do it. They fall out.


    Nice try. Grains of dust are trillions of times heavier than a molecule of air or CFC, and don't mix with it, yet they can be blown miles into the atmosphere and across oceans without immediately settling to the ground. The suggestion that CFCs can't reach the stratosphere based on their relative weight is entirely bogus. It'd be true if there were no air currents agitating the atmosphere, but that's not the case.

  37. Ozone "Hole" by thethibs · · Score: 3, Interesting

    It's not a hole—it's a depression.

    Ozone concentration increases smoothly going from the poles to the equator. It's never zero.

    The size of the so-called Ozone Hole isn't a discovery, it's a decision. Pick a threshold value and everything below that value is your "hole"—pick one value and you have a big hole, pick another and it's tiny. Different scientists at different times have used different threshold values, so it's hard to believe any comparison without checking the raw data to make sure they are comparing apples to apples.

    Using thresholds destroys interesting information. There's a real difference between a big shallow depression and a big deep depression. The total extent of the "hole" could be just a bit below the arbitrarily chosen threshold, so that a tiny change in the threshold would result in a very tiny "hole". Gotta see the data.

    --
    I'm a Programmer. That's one level above Software Engineer and one level below Engineer.
  38. Caused by BELOW average temps in Antarctica by uber_geek9 · · Score: 2, Interesting
    The increased hole size is caused by BELOW AVERAGE temperatures in Antarctica.

    From TFA:
    The temperature of the Antarctic stratosphere causes the severity of the ozone hole to vary from year to year. Colder than average temperatures result in larger and deeper ozone holes, while warmer temperatures lead to smaller ones. ... The temperature readings from NOAA satellites and balloons during late-September 2006 showed the lower stratosphere at the rim of Antarctica was approximately nine degrees Fahrenheit colder than average, increasing the size of this year's ozone hole by 1.2 to 1.5 million square miles.

    GLOBAL COOLING!!! I don't know what's happening here... warming? cooling? What does it mean anyways, that Antarctica is colder than usual?