Ozone Layer has mixed feelings towards Climate Change
While we may not see it or often think of it, the ozone layer is one of the most vital parts of the global ecosystem. It protects all living things from harmful cosmic UV-B radiation emitted from the sun. During the 1970s, a concern about the depletion of the ozone layer began to spread around the globe. Scientists wondered what was responsible for what could have become a global catastrophe, as loss of ozone could spell serious trouble for animals and plants alike. They finally confirmed that CFCs (chlorofluorocarbons) were largely responsible for the loss of ozone in earths statosphere. At the time, CFCs represented a large chunk of commercial propellants and strengthening agents, used in everything from some (even now) Albutorol inhalers, paint sprayers and mechanical lubricants to aerosol cans, pesticides and rigid foams. The US has since banned many products containing CFCs.
But how do we stop ozone depletion? Scientists think the very chemicals theorized to be the major culprit of the global warming crisis, greenhouse gases, actually slow the rates of chemical change that destroys ozone. This shows us that the greenhouse effect is actually beneficial to ozone. But, changing air currents induced by the effect can also have a negative effect on the ozone layer, as researchers from the University of Maryland found.
They ran a climate model simulator and found that the changing air circulation patterns induced an increase in air flow around Australia and argentina, delaying the ozone layers' recovery by slowing the rate of ozone production. The US, however, along with other northerly countries will see enhanced recovery of ozone as air currents slow.
The most frightening consequence of this is that UV-B radiation is responsible for skin damage that can lead to skin cancer (the radiation fractures DNA and RNA molecules and induce mutations that can lead to uncontrolled cell proliferation (cancer)). A loss of ozone means more UVB gets through the atmosphere in places like Peru, Argentina and Chile, posing potential problems for lightly skinned individuals in those countries.
These findings, however, are controversial. Further research modeling is needed, as labs in the UK have found conclusions not congruent to those proposed by the Maryland lab.
Source:
http://sciencenow.sciencemag.org/cgi/content/full/2009/206/1
Nathan Beck (Week 1)
posted by PWH @ 5:56 PM
6 comments
6 Comments:
Interesting article. I wonder if the changes in wind circulation is an actual long term solution for the depletion of the ozone. Also is there any way to rebuild ozone? It is interesting how the area in South America is in danger the most. I wonder why that is?
-Alex Pavidapha
Very interesting article. I'm a bit confused on the cause-and-effect of this theory. The emission of greenhouse gases will cause a changing of the air currents? Also, like Alex asked, why would a changing of the air currents result in hazard zones over south America and Argentina? Would the air currents change so they are not flowing away from those areas but just circulating around them?
Posted by Maura Mulvey
Interesting, it seems that the increased airflow slows down ozone production. I know chlorofluorocarbon that are broken down by UV rays releases chlorine atoms when it reaches the upper ozone layer. A single chlorine atom may cause the depletion of up to 100,000 ozone molecules. Greenhouse gases slows reactions that destroys ozone, but also at the same time it changes air circulation that increases ozone depletion. In my option greenhouse gases create a layer that protects ozone from reacting to CFCs. Then air circulation destroys it, sort of like building a wall then destroying it with your own tank. Like ocean currents that move nutrients, air circulation determines where our ozone holes are to be by moving the gases.
Do greenhouse gases actually help or destroy more ozone?
By: Peter Lau
Link
Alex -
Wind current changes would be a viable solution except that some areas of the world have the wrong type of change (an increase in wind currents is detrimental to ozone recovery). Ozone production comes about from interaction of sunlight and air - oxygen molecules get enough energy to create a stable enough O=O-O molecule. You can even purchase ground systems able to produce it.
Maura -
While the article had nothing about the mechanism of the system, I can make an educated guess as to how it changes the air currents. Greenhouse gases trap heat below the stratosphere. Because wind patterns are based on high and low fronts, which in turn are based on temperature ranges that produce varying pressures, temperature changes invariably produce changes in wind currents. So throwing in more heat (from the gases) is like throwing a wrench into the system. I'm not sure why south America and Argentina are particularly at risk. Perhaps because they are nearest to the south pole. Poles inherently receive less light than other areas = less sunlight = less ozone.
Peter -
That's a good thought. My only riposte would be the fact that O=O-O is an unstable molecule and perhaps greenhouse gases actually react with it. I've seen reactions on paper wherein many nitrogen-oxygen molecules destroy ozone and leave us with acid and water. CFCs are particularly dangerous because ionized Cl and F that come about from UVB reaction are hugely reactive and can polarize many things. Perhaps it is Cl and F reaction with greenhouse gases that produces even more products that destroy ozone?
With regards to your last question - both, or so the researchers concluded. The greenhouse gases slow ozone depletion but induce wind changes that hasten ozone depletion.
Thanks for your reviews
[Nathan Beck]
Nice writing. Does it mention how quickly ozone regenerates on its own and if our rates of emission have decreased enough to allow this? How long would it take?
(Nicholas Skvir 21798087)
Nice article. It would be quite ironic if the same CFCs we thought were ruining the ozone turned out to actually be slowing down its degradation. If this turns out to be the case, do you think government agencies will change their policies or even intentionally release these CFCs into the air?
(Calin Darabus)
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