Posted on 05/26/2006 10:43:28 AM PDT by Hunble
May 26, 2006: Think of the ozone layer as Earth's sunglasses, protecting life on the surface from the harmful glare of the sun's strongest ultraviolet rays, which can cause skin cancer and other maladies.
People were understandably alarmed, then, in the 1980s when scientists noticed that manmade chemicals in the atmosphere were destroying this layer. Governments quickly enacted an international treaty, called the Montreal Protocol, to ban ozone-destroying gases such as CFCs then found in aerosol cans and air conditioners.
The Antarctic ozone hole.
Today, almost 20 years later, reports continue of large ozone holes opening over Antarctica, allowing dangerous UV rays through to Earth's surface. Indeed, the 2005 ozone hole was one of the biggest ever, spanning 24 million sq km in area, nearly the size of North America.
Listening to this news, you might suppose that little progress has been made. You'd be wrong.
While the ozone hole over Antarctica continues to open wide, the ozone layer around the rest of the planet seems to be on the mend. For the last 9 years, worldwide ozone has remained roughly constant, halting the decline first noticed in the 1980s.
The question is why? Is the Montreal Protocol responsible? Or is some other process at work?
It's a complicated question. CFCs are not the only things that can influence the ozone layer; sunspots, volcanoes and weather also play a role. Ultraviolet rays from sunspots boost the ozone layer, while sulfurous gases emitted by some volcanoes can weaken it. Cold air in the stratosphere can either weaken or boost the ozone layer, depending on altitude and latitude. These processes and others are laid out in a review just published in the May 4th issue of Nature: "The search for signs of recovery of the ozone layer" by Elizabeth Westhead and Signe Andersen.
Sorting out cause and effect is difficult, but a group of NASA and university researchers may have made some headway. Their new study, entitled "Attribution of recovery in lower-stratospheric ozone," was just accepted for publication in the Journal of Geophysical Research. It concludes that about half of the recent trend is due to CFC reductions.
Lead author Eun-Su Yang of the Georgia Institute of Technology explains: "We measured ozone concentrations at different altitudes using satellites, balloons and instruments on the ground. Then we compared our measurements with computer predictions of ozone recovery, [calculated from real, measured reductions in CFCs]." Their calculations took into account the known behavior of the sunspot cycle (which peaked in 2001), seasonal changes in the ozone layer, and Quasi-Biennial Oscillations, a type of stratospheric wind pattern known to affect ozone.
What they found is both good news and a puzzle.
The good news: In the upper stratosphere (above roughly 18 km), ozone recovery can be explained almost entirely by CFC reductions. "Up there, the Montreal Protocol seems to be working," says co-author Mike Newchurch of the Global Hydrology and Climate Center in Huntsville, Alabama.
The puzzle: In the lower stratosphere (between 10 and 18 km) ozone has recovered even better than changes in CFCs alone would predict. Something else must be affecting the trend at these lower altitudes.
The "something else" could be atmospheric wind patterns. "Winds carry ozone from the equator where it is made to higher latitudes where it is destroyed. Changing wind patterns affect the balance of ozone and could be boosting the recovery below 18 km," says Newchurch. This explanation seems to offer the best fit to the computer model of Yang et al. The jury is still out, however; other sources of natural or manmade variability may yet prove to be the cause of the lower-stratosphere's bonus ozone.
Whatever the explanation, if the trend continues, the global ozone layer should be restored to 1980 levels sometime between 2030 and 2070. By then even the Antarctic ozone hole might close--for good.
05.26.2006
Earth's ozone layer appears to be on the road to recovery. + Play Audio | + Download Audio | + Email to a friend | + Join mailing list
May 26, 2006: Think of the ozone layer as Earth's sunglasses, protecting life on the surface from the harmful glare of the sun's strongest ultraviolet rays, which can cause skin cancer and other maladies.
People were understandably alarmed, then, in the 1980s when scientists noticed that manmade chemicals in the atmosphere were destroying this layer. Governments quickly enacted an international treaty, called the Montreal Protocol, to ban ozone-destroying gases such as CFCs then found in aerosol cans and air conditioners.
Right: The Antarctic ozone hole. [More]
Today, almost 20 years later, reports continue of large ozone holes opening over Antarctica, allowing dangerous UV rays through to Earth's surface. Indeed, the 2005 ozone hole was one of the biggest ever, spanning 24 million sq km in area, nearly the size of North America.
Listening to this news, you might suppose that little progress has been made. You'd be wrong.
While the ozone hole over Antarctica continues to open wide, the ozone layer around the rest of the planet seems to be on the mend. For the last 9 years, worldwide ozone has remained roughly constant, halting the decline first noticed in the 1980s.
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The question is why? Is the Montreal Protocol responsible? Or is some other process at work?
It's a complicated question. CFCs are not the only things that can influence the ozone layer; sunspots, volcanoes and weather also play a role. Ultraviolet rays from sunspots boost the ozone layer, while sulfurous gases emitted by some volcanoes can weaken it. Cold air in the stratosphere can either weaken or boost the ozone layer, depending on altitude and latitude. These processes and others are laid out in a review just published in the May 4th issue of Nature: "The search for signs of recovery of the ozone layer" by Elizabeth Westhead and Signe Andersen.
Sorting out cause and effect is difficult, but a group of NASA and university researchers may have made some headway. Their new study, entitled "Attribution of recovery in lower-stratospheric ozone," was just accepted for publication in the Journal of Geophysical Research. It concludes that about half of the recent trend is due to CFC reductions.
Lead author Eun-Su Yang of the Georgia Institute of Technology explains: "We measured ozone concentrations at different altitudes using satellites, balloons and instruments on the ground. Then we compared our measurements with computer predictions of ozone recovery, [calculated from real, measured reductions in CFCs]." Their calculations took into account the known behavior of the sunspot cycle (which peaked in 2001), seasonal changes in the ozone layer, and Quasi-Biennial Oscillations, a type of stratospheric wind pattern known to affect ozone.
What they found is both good news and a puzzle.
The good news: In the upper stratosphere (above roughly 18 km), ozone recovery can be explained almost entirely by CFC reductions. "Up there, the Montreal Protocol seems to be working," says co-author Mike Newchurch of the Global Hydrology and Climate Center in Huntsville, Alabama.
Right: The ozone layer is located about 15+ km above Earth's surface. [More]
The puzzle: In the lower stratosphere (between 10 and 18 km) ozone has recovered even better than changes in CFCs alone would predict. Something else must be affecting the trend at these lower altitudes.
The "something else" could be atmospheric wind patterns. "Winds carry ozone from the equator where it is made to higher latitudes where it is destroyed. Changing wind patterns affect the balance of ozone and could be boosting the recovery below 18 km," says Newchurch. This explanation seems to offer the best fit to the computer model of Yang et al. The jury is still out, however; other sources of natural or manmade variability may yet prove to be the cause of the lower-stratosphere's bonus ozone.
Whatever the explanation, if the trend continues, the global ozone layer should be restored to 1980 levels sometime between 2030 and 2070. By then even the Antarctic ozone hole might close--for good.
It's being repaired by Global Warming.
The "OZONE HOLE" is one of the biggest frauds that has ever been done on the public.
It relies on superstition and misinformation which is being routinely debunked.
O3 (ozone) is created when O2 is hit with UV radiation, then splits into (2) O1 molecules. O1 and O2 are naturally attracted to each other as a result of their charge, and NORMALLY form O3. When UV radiation is low, the ozone layer will be thin. THIS IS THE CASE EVERY YEAR, OVER EACH OF THE POLES AS THEY ARE TILTED AWAY FROM THE SUN!
Several years ago ACTIVIST scientists decided to call THINNING of the Ozone layer a "hole" even though it was NOT an actual "hole."
The ozone is self-regulating, more UV, thicker ozone layer. Less UV, thinner ozone layer.
Want PROOF of the fraud? Why is it that we have regular "high pollution" alert days when Ozone levels are high but somehow it's a disaster when it's thin up above?
So ozone is considered dangerous pollution down here, and the earth is going to somehow disintegrate when the layer gets thin up in the stratosphere.
No one has ever explained how the CFCs got up into the upper atmosphere levels to destroy the ozone. And why is the hole over Antartica a problem? No one lives there, scientists notwithstanding...........
Could this ozone hole be caused by Mount Erebus in Antarctica?
You need to read up a bit more on the subject, because the above statement is quite silly.
"No one has ever explained how the CFCs got up into the upper atmosphere levels to destroy the ozone."
CFCs are much, much heavier than any of our other common atmospheric gases and I don't see how it is possible to lift it with convection to the outer atmosphere.
You have good questions. I wonder if the hole has been there ever since we developed the technology to look. If so, how do we know there was ever a time when the hole wasn't there?
Yep, and durn little UV radiation will reach the surface of the earth's polar regions, ozone "hole" or no ozone "hole", if there isn't any UV radiation to start with during winter.
Is this actually so? It's gotten such that I don't believe anything I read about environmental crises, even from NASA.
I'd be asking a more important question...what if the hole was there for a good reason, and now...we may be sliding toward a ice age or global cooling. If you can't explain the logic of it being there in the first place...the opposite is true as well.
PC ideology parading as science.
"Is this actually so? It's gotten such that I don't believe anything I read about environmental crises, even from NASA."
You won't believe science agencies, so rely on posters to an internet forum to know the truth? LOL
Let's see if we can make this statement a little more accurate:
People were understandably alarmed, then, in the 1980s when scientists noticed that manmade chemicals in the atmosphere were destroying a change in this layer and made the unfounded assumption that the change was caused by manmade chemicals in the atmosphere, with the most widely blamed chemicals being heavier than atmosphere and thus highly unlikely to rise to sufficient altitude to even have an effect on the ozone layer.
Concentrated ozone where we breathe it is a bad thing.
While I agree that the ozone debate has been heavily skewed, your argument is like "Why is a layer of tar on the roof a good thing, and having it aerosolized into my Central Air bad?
Take a very close look at the image of the "Ozone Hole" and pay attention to the red ring that is around the Earth's pole.
Notice how the Earth's ozone forms a donut around the polar region and is very concentrated in that area?
To understand this, you must answer these very simple questions:
1) At the Earth's poles, why is it dark for six months of the year?
2) When the Sun sets, why is the sky red?
3) Spring is when the Sun appears to move toward the equator on Earth. At what times do the poles receive sunlight after a long winter?
4) Ozone is created when sunlight ionizes a normally stable O2 molecule and splits it in half. The two free Oxygen atoms may combine with each other or form a bond with other O2 molecules. If an singular Oxygen atom combines with a stable Oxygen molecule (O2), is O3 (Ozone) being produced?
5) Sunlight is the only force in the upper atmosphere that splits the normally stable O2 molecules into separate ions of Oxygen. Those free Oxygen ions are then allowed to combine with other Oxygen molecules. Without Sunlight or other high-energy sources, can new Ozone (O3) molecules be formed?
They went to all the top universities and media outlets of the time. "We must stop the huge hole from getting larger! Dire consequences await if we do not do this! The entire North American continent is at risk from this huge hole. If it grows any more the entire planet may be doomed! We must stop all exploration of the New World at once!"
Fortunately, the King of Spain was an intelligent man and had them thrown into the dungeons of The Inquisition never to be seen and heard form again...............
Did you even notice that there isn't a clearly defined "Oxygen Layer, Nitrogen Layer, Carbon Dioxide Layer" etc? It's because once gases disperse, they don't much settle due to Brownian motion. Way up high, where there are few other molecules to bump against, the molecular weight starts to have a significant effect, but that is waaaaay out there.
I have been trying to tell people this for years, but they only see the blue area around the pole.
What is that highly concentrated Ozone ring (depicted as red) around the "Ozone Hole?"
Why does the Earth have highly concentrated rings of Ozone around the poles during spring?
The global warming debate and the ozone "hole" debate are largely independent. One could easily be true while the other false - though there are some incidents that will affect both.
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