Ozone layer shows signs of recovery: scientists

[southernleftylady]

LONDON (Reuters) - The ozone layer is showing signs of recovering, thanks to a drop in ozone-depleting chemicals, but it is unlikely to stabilize at pre-1980 levels, researchers said on Wednesday.

Depletion of the earth's protective ozone layer is caused by the chemical action of chlorine and bromine released by man-made chlorofluorocarbons (CFCs), which are used in aerosol sprays and cooling equipment.

Ozone-depleting chemicals were banned by the 1987 Montreal Protocol which has now been ratified by 180 nations.

"We now have some confidence that the ozone layer is responding to the decreases in chlorine levels in the atmosphere due to the leveling off and decrease of CFCs," said Dr Betsy Weatherhead, of the University of Colorado in Boulder
http://news.yahoo.com/s/nm/20060503/sc_nm/environment_ozone_dc

[Canuckistanian]

1. Good news, especially for Australians

And South America and South Africa. They're affected the most by this "hole" above the Antarctic.

[CountAllVotes]

5. the Hawaiian islands have ozone alerts almost every day

So it is not just South America and South Africa that are being affected. When you go to Hawaii you hear alerts on the radio and some days they tell you not to go outside as there is a hole in the ozone layer over the islands. :(

:kick:

[Canuckistanian]

6. Really? I didn't know that

That hole must shift around a lot.

[CountAllVotes]

7. I didn't know it either!

Believe me, I was shocked! I was in Maui driving south on the highway and they had an alert on the radio go off.

I was also in Kauai a few years later and the same thing happened. I asked someone that lives there about it and they said, "oh yeah, there's a hole in the ozone layer over the islands ...".

So, we know now don't we?

*eek*

:kick:

[Knurled99]

8. Not an ozone hole...

The alerts are from too much ozone in the air. (Ozone is simply oxygen. Usually, because it is so unstable by itself, oxygen binds into groups of two, as in H2O or CO2. Ozone, which is O3 usually turns into O2 because two O3 molecules combine to make three O2 molecules. Ozone exists naturally in the upper atmosphere... until those CFC's which are very light in weight, make it up there and start bonding with the ozone molecules.)

Ozone is also a product of several things like air-conditioners, agricultural by-products, etc. It's a lung irritant so they make kids stay inside on hot days when the conditions are right for there to be a lot of ozone in the air.

[Gman]

9. Ozone is

O₃ and I believe it is unstable because of the 3 combination. Its easier to split back off into individual O^-2 ions that combine with other oppositely charged ions.

[Lisa]

10. from the EPA -- "good up high, bad nearby"

The same chemical, but as you say, it has different implications depending on where in the atmosphere it occurs. In the stratosphere it's formed naturally by UV radiation bombarding oxygen (and it helps absorb those same UV wavelengths and protects us down below). In the troposphere, near the surface, it's formed during the photochemical reactions between nitrogen oxides and volatile organic compounds (like benzene) -- associated with "smog".

[Solon]

11. Ozone alerts are different...

Due to many different types of industrial byproducts, ozone is produced in the lower atmosphere and is a severe lung irritant and can damage your lungs. Its also a possible reason for the uptick in childhood asthma in cities. Our city in the Midwest has Ozone alerts during the summer, probably a combination of fertilizer runoff and industrial reactions with the Mississippi and Missouri rivers. We actually have Ozone level alerts, color coded air quality charts, from green, yellow, orange, to red, we mostly get up to orange in our area.

[codebuster11]

2. good

Well at least there is some good news about the environment and our planet.

[lvx35]

3. Yeah, it goes to show that we can make serious changes.

We just need to get our heads together and do the work.

[Lisa]

4. it's working!

This is great news. Given that the corporations responsible for producing CFCs and other ozone-depleting chemicals were wailing that they would be ruined by the Vienna Convention (and Montreal Protocol, and subsequent beefing-up of the legislation) -- and that the right-wingers were scoffing that it would never fly -- it's good to hear this.

It's going to be harder for them to argue that there are no precedents to international action on something as big as global warming, when the ozone treaty appears to be working. (Of course they will probably just turn around and say that the ozone layer was never in danger to begin with, rather than admit that the Montreal Protocol is a success.)

[robcon]

12. Air pollution is declining almost everywhere in the U.s.

It's not just the ozone hole, it the quality of the air we breathe. With very few exceptions all major cities have much fewer air quality alerts than was the case 20 years ago.

Environmental policy works.

[Zynx]

13. My parents told me how bad it used to be in Milwaukee before green laws.

Many buildings turned black from the pollution.

[Lisa]

14. yes -- SO2 emissions are down

This is helping some of the areas once affected by acid rain, like the Canadian Shield, where the acidity of lakes is stabilizing or even reversing. (Actually, Bush's dad helped by strengthening the Clean Air Act, under pressure from the New England states). SO2 (from burning coal) was a major contributor to the "old" kind of smog -- of the type seen in the 1800s and early 1900s, like those pea-souper fogs that enveloped London and Glasgow.

However, we still have problems from the "new" smog -- photochemical reactions with car exhaust. Areas like Vancouver and Toronto, which used to have pretty decent air quality in the 1970s, regularly have problems now in the summer just like LA does.

I agree that there are a lot of things which have been improved thanks to policy ... getting rid of leaded gasoline, for example. Though we still have a lot of work to do in other areas.