Greenhouse effect ???

dmccarty · Feb 2, 2006

CRJCaptain,

Most likely I heard that the holes had decreased/filled in on NPR.

And no I don't need to learn anymore on the subject. Either the problem is some long term event that has been going on forever in human terms or the science is correct and the CFC ban will solve the problem.

Later,
Dan

Chuck52 · Feb 2, 2006

( ( and we can safely store the by products, )

How can one possibly say this, knowing those by-products can remain a hazard for 100,000 + years?

Nuclear energy has its place, but the cost to future generations is an unknown and should not be taken lightly.

-Mike Z. /forums/images/graemlins/grin.gif )

Which is why I said we'd have to agree on a definition of "safely", or agree to disagree. TANSTAFL. And there Also Ain't No Such Thing As Absolute Safety. Or absolute anything. Except as a theoretical limit, such as Absolute Zero temperature.

Chuck

cp1969 · Feb 2, 2006

( Well, I don't know where you're getting your information, but the ozone hole at both poles is an annual occurrence. )

And how is it that all the ozone-damaging CFC's migrate to the poles to cause these holes? I'm assuming this must occur since it seems penguins and Eskimos would have little use for air conditioning and therefore not have a lot of CFC's around.

AutoUnionTypeC · Feb 2, 2006

( And how is it that all the ozone-damaging CFC's migrate to the poles to cause these holes? I'm assuming this must occur since it seems penguins and Eskimos would have little use for air conditioning and therefore not have a lot of CFC's around. )

Your answer can be found here. /forums/images/graemlins/cool.gif

CFC's & the Ozone Hole

cp1969 · Feb 2, 2006

from the link:
( Ozone over the northern hemisphere was at the
thinnest level ever recorded last year (but we have only been recording for a
few years, and Mt. Pinatubo had much to do with the recent thinning). )

Two things: Could it be that thickness of the ozone layer is a naturally varying quantity regardless of man's influence and how much is "Mount Pinatubo had much to do with the recent thinning."

I'm not sure that he link between CFC's and ozone depletion has been concretely established.

NewToy · Feb 2, 2006

I read an article a while back on smuggling CFC's into the USA. They said the majority of it was coming from India. We can legislate it into oblivion but when they make it and use it in other countries we'll still suffer the consequences. It's a small world after all.

John

HGM · Feb 2, 2006

Yep, its all our fault, dont forget it........... /forums/images/graemlins/wink.gif

CT_Tree_Guy · Feb 2, 2006

And how is it that all the ozone-damaging CFC's migrate to the poles to cause these holes? I'm assuming this must occur ... 

I just did some research into the subject and learned that it doesn't have to do with ozone-damaging CFC's migrating to the poles, but rather with unique atmospheric conditions in Antarctica, where the ozone holes have been largest.

Here's a highlight:

 Severe depletion first appeared over Antarctica because
atmospheric conditions there increase the effectiveness of
ozone destruction by reactive halogen gases.
The formation of the Antarctic ozone hole requires abundant
reactive halogen gases, temperatures low enough to
form polar stratospheric clouds (PSCs), isolation of air
from other stratospheric regions, and sunlight. 

The main thing seems to be the polar stratospheric clouds, which seem to do odd things to the ozone molecules.

If anyone's up for some good news, it appears that ozone levels are due to return to normal by the mid-to-late 21st century. It seems that enough nations are abiding by, and will likely continue to abide by international agreements on CFC reduction that this problem seems to be on the raod to being solved. How about that.

EddieWalker · Feb 3, 2006

I seem to remember a story that scientist digging holes in Antarctica have found evidence of the hole in the ozone layer growing and shrinking for thousands of years.

The hole used to be big news, than this came out and it sort of went away.

Kind of like the spotted owl. The poor spotted owls were almost extinct in the old growht forest and the news was all about saving the old growth to protect the spotted owls. Than scientist found out the spotted owls were moving to the new growth forest where they were more successfull hunting, and they also found out the Southern Spotted Owl was the exact same species. Turns out there are lots and lots of spotted owns and they are doing fine. End of crises and nobody talks about spotted owls anymore.

This is a fun thread, thanks for all the great informatinon.
Eddie