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Sun Storms Deplete Ozone, Too
An anonymous reader writes "Turns out the sun itself zaps the ozone that protects us from the sun. LiveScience is reporting that the record-setting string of solar storms around Halloween in 2003 (including an X28 flare) set off a cascade of events that depleted the ozone layer over the Arctic in early 2004. In a nutshell, more nitrogen was created, and an unusually strong vortex of high-speed winds aloft brought the nitrogen down, where it contributed to cutting ozone by 60 percent over the polar region. In January, the a European scientist warned residents of the far north to basically stay out of the sun. While chlorofluorocarbons are still blamed for ozone depletion, scientists said this study shows they don't properly account for the sun's impact."
Testing to see if something depletes ozone can be done in a lab. It's really not speculation to say that CFCs destroy ozone.
If you missed the Aurora Show this fall, you missed something special. The Aurora were intense and visible in most urban places. (Including me in Minneapolis)
For information on when flares and aurora are possible, see the following pages:
aurora alert- http://www.xs4all.nl/~carlkop/auralert.html/
for more of a daily "this is cool stuff in space" see
SpaceWeather.com http://spaceweather.com/
Fun Stuff.
It could be worse, it could be Monday.
High in the atmosphere, some oxygen (O2) molecules absorbed energy from the Sun's ultraviolet (UV) rays and split to form single oxygen atoms. These atoms combined with remaining oxygen (O2) to form ozone (O3) molecules, which are very effective at absorbing UV rays. The thin layer of ozone that surrounds Earth acts as a shield, protecting the planet from irradiation by UV light...Ozone is produced naturally in the stratosphere when highly energetic solar radiation strikes molecules of oxygen, O2, and cause the two oxygen atoms to split apart in a process called photolysis.
Linkage
So, yeah, the sun is the bad guy, but really, the sun is the good guy, too. =)
It's scientifically proven, that CFCs destroy ozone in the lab. Now weather or not it contributes to significant depletion of ozone in the upper atmosphere, is of question.
yes, but significant climate change is occuring now in mere generations rather than over k's of years.
This article is more to do with global warming (as opposed to ozone depletion), but it gives a good perspective.
Mongrel News all the news that fits and froths
... why I don't believe the "Global Warming is being caused by greedy corporations" spiel..
And what does Global Warming have to do with ozone-layer depletion?
These are two completely seperate phenomena.
quite simply, it's because most people (scientists included) quite simply don't have enough information to say for a FACT that THIS or THAT is causing ozone depletion
Wrong. CFCs do cause ozone depletion. That is established. The mechanisms of how CFCs catalyze the degradation of ozone into oxygen are fully understood. It is something you can easily reproduce in a laboratory. This has been done many times. A Nobel prize was awarded for this. They don't give out Nobels for things which aren't considered to be well-established.
You are confusing this issue with global warming, which is far more controversial, and something which is far less easy to know with certainty.
As for the quote:
"While chlorofluorocarbons are still blamed for ozone depletion, scientists said this study shows they don't properly account for the sun's impact."
It is also correct. But what they are saying is that the extent of ozone destruction due to CFCs wasn't correct before, since they didn't take this factor into consideration. It does not mean that CFCs don't destroy ozone. They do. And it's no theory.
CFC's are incredibly heavy. In order to reach the ozone layer, the CFC's have to be super-heated.
The ozone cover of our atmosphere is a dynamic process meaning that ozone is formed and destroyed at a constant rate as we speak. True that solar flares cause it to be destroyed but such phenomenon does not happen too often. In the time span between two such events the ozone can re-create itself. On the other hand, destruction of ozone by human made CFC's, freons, etc are spontaneous and hence causes permenant depletion.
Fact: the article was about the ozone layer, not the greenhouse effect, and the two are largely unrelated (other than tropospheric ozone levels contributing to the greenhouse effect, but that was not what the article was about). The parent post is offtopic, not insightful.
The size of the hole(s) in the ozone layer is not the same problem as global warming. Greenhouse gases are irrelevant.
- Ozone (a molecule with three oxygen atoms) can be broken back down into O2 + O. Like all chemical reactions, this process goes both ways: free oxygen atoms combine into O2, or with O2 to form O3. Ozone in the stratosphere undergoes this process naturally while absorbing UV from the sun.
- Breaking oxygen to form ozone is a slow process as it absorbs energy. Breaking ozone to form oxygen progesses at a much higher rate.
- There's a LOT of oxygen in the atmosphere. The stratosphere reaches an equilibrium where a relatively small amount of ozone breaking down quickly is balanced by a lot more oxygen being photolyzed slowly.
- CFCs break down into chlorine, which catalyzes the O3 -> O2 + 0 reaction. This causes the ozone depletion direction to increase its rate, without an increase in ozone production. Thus, the total amount of ozone will decrease until a new equilibrium is reached at a lower level of ozone.
- Note that the chlorine is a catalyst, and thus is not consumed in the reaction. One chlorine atom can destroy hundreds of thousands of ozone molecules while it's in the stratosphere. So, a relatively small amount of CFCs has a much larger effect on the amount of ozone.
- Cold temperatures favor the ozone depletion direction of the reaction. This is why you see the hole appear first over the southern polar regions. That's the coldest place. Increases in the size of the hole and more northly locations indicate ever dropping levels of ozone across the atmosphere. If you think of the ozone as water in the ocean, then the ozone hole is an island sticking up out of water. Draining water from the entire ocean makes the island bigger, but that doesn't mean the water is only being lost at the island.
- "Ozone depletion deniers" used to exist, much like those that currently object to global warming. They had various objections, such as no known mechanism to transport CFCs released at ground level to the stratosphere. You also used to see a lot of objections that have familiar analogs in the global warming debate -- for instance, suggestion of natural sources such as chlorine from sea salt rather than CFCs. Satellite observations have observed tagged chlorine atoms from CFCs in the stratosphere. We know it's human-produced stuff up there causing problems.
- The chlorine will eventually be removed from the stratosphere as it combines with something other than ozone, though this process isn't as fast as we would like. By ceasing use of CFCs, the chlorine derived from them will eventually go away, and the ozone layer will reestablish at the old equilibrium we used to know and love. Changing human behavior can fix this problem as well as cause it.
One correction:
Cold temperatures favor the ozone depletion direction of the reaction. This is why you see the hole appear first over the southern polar regions.
Perhaps, but don't forget that ozone is created by UV hitting O2. In the polar regions in winter (when the hole happens) there is no sun, and thus no ozone creation. Those natural processes you have cited are all there working to destroy ozone, but nothing is creating it at the time.
It appears large amounts of discussion here are happening with people not understanding anything at hand. I will attempt to clarify some things to the best of my ability. Please excuse me if this is not as great as it could be, as my source here is my memory augmented by google.
The atmosphere is a very complex thing in both composition and behavior. For purposes of this slashdot discussion, though, about the only important thing about its behavior is that different gases exist in different compositions in different parts of the atmosphere, and these different gases block and reflect different frequencies of radiation. (Most of these gases exist in a cycle, where they are emitted out of the earth, usually by volcanic sources, then slowly fall out of the atmosphere, and are subducted back into the earth, where they're eventually re-emitted.) There are two specific important aspects to this. The first is a layer of ozone which blocks certain higher frequencies of incoming radiation from the sun. The second is a layer of "greenhouse gases" which block a lower frequency. This lower frequency of radiation is not so much important coming from the sun; however, it is important because when radiation hits the earth, it is absorbed and re-emitted as "longwave radiation"-- and this radiation has a frequency such that it is partially blocked by the greenhouse gases, keeping it inside the earth. All of this is very convenient for the forms of life currently common on earth, since the higher frequencies the ozone keeps out are harmful to this life and the lower frequencies the greenhouse gases keep in provide useful heat, keeping the earth from just being a big ball of ice like mars is. Perhaps if the atmosphere were different, life would have evolved differently and less or more heat, or more high-frequency radiation, would not be a bother. But it is the forms of life that live on earth right now we care about, specifically humans.
The ozone layer is the important thing as far as this article goes. The problem is that the ozone layer has been depleting in recent years, starting around World War II, and accelerating in the 60s and 70s. In recent decades the problem has become so bad that the ozone layer actually is developing holes in it, around the north and south poles, mainly the south. This depletion has corresponded with increased levels of chlorofluorocarbons in the atmosphere. Chlorofluorocarbons, or CFCs, come from a number of sources. For example volcanoes put out CFCs in great quantity every time they erupt. When placed in the vicinity of certain gases-- specifically the gases found in the ozone layer of the atmosphere-- these CFCs catalyze chemical reactions which destroy ozone, converting it to oxygen. An individual CFC molecule, when it gets into the ozone layer, will thus cause this process pretty much continuously, until like all gases it falls out of the atmosphere. There isn't particularly any question about this, as these processes are easily experimentally reproduced. The other thing that isn't particularly a question is that the increased CFC levels from WWII on were a result of human industrial processes. CFC outputs by human industry after its first uses dwarfed the natural sources of same, leading to a continuous and steady increase in cfc levels far beyond what atmospheric processes are accustomed to. By 1987 it became clear that this human CFC output was having a negative impact on the ozone layer, leading to the adopting of the Montreal Protocol, a treaty which drastically reduced human CFC output with the goal of eliminating human CFC production entirely worldwide by 2010. The impact on CFC levels of the montreal protocol was dramatic and immediate; you can see here yourself that as soon as the significant human CFC sources stopped at the end of the 80s, the steady increase in CFC levels flattened out and became constant. (I am afraid this graph comes from a
Irritable, left-wing and possibly humorous bumper stickers and t-shirts
Greenhouse gases (linked to global warming) and CFCs (linked to ozone depletion) are not related. Please see my other post in this thread.
Irritable, left-wing and possibly humorous bumper stickers and t-shirts
Finally someone looks at NATURAL causes instead of using junk science to explain things. Here's a site to look at.
Let's see how many enviro-crack-pots claim that humans are STILL a significant detrimental factor in the depletion of the ozone.
CFCs work by turning O and O3 into O2s. Like all chlorine. You know, that stuff that gets released in massive amounts every time a volcano goes off.
You ever notice that they'll claim 'CFCs have been detected in the ozone layer', but never tell you how much, or what percentage they are versa other chlorine?
If corporations are people, aren't stockholders guilty of slavery?
Antarctica seems to be cooling, and its coastal ice pack is thicker than ever.
I do hope you're right about global warming, because global cooling looks at least as probable, given the few hard facts we actually know. Global warming would clearly leave the world a better place for all of us (especially the world's poor and hungry!), with more rainfall, warmer winters, more food, and so on. Global cooling, on the other hand, would probably kill more of the poor folks in Africa than the muslims' genocide and AIDS and Kyoto all put together.
I've got some links to facts and discussion of glaciers, ice packs, temperature series and so on at http://geocities.com/nelstomlinson/globalwarming.h tml
See what I've been reading.
But what percentage of melanoma patients are under 30, and how many are over 30? This site says that almost 90% of recent melanoma patients are over 40 years old.
This site, http://www.cancer.org/ has an article from 2002 that states:
So those under 30 are getting less melanoma now than before, and the elderly are getting much more.
As I said, statistics are great.
I have to stop wasting so much time reading Slashdot. It's interfering with my crystal meth addiction.
This is how ozone is made (the "source" reaction):
O2 + UV(180-240nm) -> O* + O*
O* + O2 -> O3
Its famed ability to absorb UV happens this way:
O3 + UV(200-320nm) -> O* + O2
O* + O2 -> O3 (again)
and this is the normal "sink" reaction, which removes the ozone-producing O* radicals from circulation:
O* + O* -> O2
(Another normal "sink" is O* + O3 -> 2O2.)
Normally both the "source" and "sink" reactions are happening at once, so that the concentrations of O3 relative to O2 are at an equilibrium- as much ozone is being produced as destroyed at any given moment.
This is the chlorine breakdown path:
Cl* + O3 -> ClO* + O2
ClO* + ClO* -> Cl2O2
Cl2O2 + UV -> 2Cl* + O2
overall: 2O3 -> 3O2
Cl* is a chlorine radical formed when CFCs break down under intense UV. The chlorine reactions happen at the surface of certain types of ice crystals that form at -80 degrees C. That's where we get the "ozone holes" from.
The overall reaction is an efficient ozone sink, with a rate of reaction 1500 times greater than the one with O*. This pushes the O3/O2 equilibrium downward. More ozone is continually being produced by sunlight hitting O2, but since the O3 is disappearing faster, the result is a much lower concentration of O3 relative to O2 than if no Cl* were present.
This article is so dumbed down as to be worthless. It blames "nitrogen gas", which is a load of crap. This story is about nitric oxide (NO) catalysis. This is a well known phenomenon. In addition to chlorine and nitric oxide, fluorine and bromine can also catalyze the breakdown of ozone. This is how nitrogen oxide breaks down ozone:
NO + O3 -> NO2 + O2
O2 + UV(180-240nm) -> O* + O*
NO2 + O* -> NO + O2 (as opposed to O* + O2 -> O3 which would regenerate the ozone)
Similar reactions happen in reverse near the ground in cities, where the NO2 that emerges from tailpipes results in ground-level ozone.
Normally there's much more NO than chlorine in the stratosphere, although the chlorine reactions are more efficient. Weather patterns above the poles have always brought a steady stream of NO down from the ionosphere to the stratosphere since the beginning of time. In other words the historic, preindustrial "normal" equilibrium concentration of ozone already accounts for what the sun does in a normal solar year. The solar storms of 2003 created an abnormal surge of NO, so we saw ozone drop markedly in spring 2004 relative to 2003. But 2003 levels were already depressed, and we had normal NO levels then.
NO and chlorine are both gradually cleared from the stratosphere by formation of nitric acid and hydrochloric acid respectively. So the supplies of these harmful catalysts have to be regenerated, either by the sun or us. But NO turns to nitric acid after only a couple days. A CFC molecule survives an average of 100 years before degrading to elemental chlorine (destroying ozone) and then HCl. Drops in ozone levels from solar activity can be expected to be transient, lasting a year or two at most. Drops in ozone levels from CFCs are essentially permanent for the rest of our lives. Don't let anyone fool you into thinking all our problems are the sun's fault.
No, seriously. The thing about science is that everything has to be proven, and everything _can_ be wrong or superceded by a better theory.
It means that yes, you're _supposed_ to question everything, be it the theory of relativity, or gravity, or global warming theories. That's what science is all about. Trying to see if you can improve the existing understanding of the world, instead of joining the lemming parrade.
The moment you've found absolute truths, evidence be damned, that's no longer science. That's _religion_.
It doesn't matter if it's about Christ, or lung cancer, or global warming. The moment you have your absolute truth and don't need no stinkin' scientists telling you about experimental evidence, or worse yet start accusing them of hidden agendas or being the enemy... congrats, you've reinvented the Inquisition. What lies that-a-way is not science, it's not environmentalism, it's religion.
A polar bear is a cartesian bear after a coordinate transform.
Alas, I wouldn't trust measurements from thermometers located in urban areas, though. Scientists discovered that when you keep "official" thermometers in urban areas they tend to skew higher due to urban development in the last 100 years or so.
Measurements done at "official" thermometers done at rural locations actually show very little (if any) increase in local temperatures in the last 100 years.
Gamingmuseum.com: Give your 3D accelerator a rest.