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Ozone: The Earth's protective shield is repairing

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Re: Ozone: The Earth's protective shield is repairing

#51

Post by philipkglass »

xavierstein wrote: post #24

My father-in-law firmly believes that the hole in the ozone was caused by space shuttle reentry, and that's why it's patching now, and also that CFCs couldn't possibly make the hole because they are heavier than air. Does anyone have the data to refute these claims?

"Chlorofluorocarbons (CFCs) are heavier than air, so how do scientists suppose that these chemicals reach the altitude of the ozone layer to adversely affect it?"

https://www.scientificamerican.com/article/chlorofluorocarbo...

Also, see the definition of homosphere:

https://en.wikipedia.org/wiki/Atmosphere_of_Earth#Other_laye...

"The homosphere and heterosphere are defined by whether the atmospheric gases are well mixed. The surface-based homosphere includes the troposphere, stratosphere, mesosphere, and the lowest part of the thermosphere, where the chemical composition of the atmosphere does not depend on molecular weight because the gases are mixed by turbulence. This relatively homogeneous layer ends at the turbopause found at about 100 km (62 mi; 330,000 ft), the very edge of space itself as accepted by the FAI, which places it about 20 km (12 mi; 66,000 ft) above the mesopause."

Note that the ozone layer is well within the homosphere so CFCs readily mix into it from surface emissions.

Re: Ozone: The Earth's protective shield is repairing

#52

Post by cmeranda »

xavierstein wrote: post #30
pm wrote: post #26

Earlier quoted context omitted.

Does he have data to back up those claims?

I guess I'm more looking for a response to "yes CFCs can destroy ozone even though they are heavier than air," and "here is a graph of the size of the ozone vs space shuttle reentries" that shows a non-correlation.

Have you tried just getting him to read the Wikipedia page? It describes how those gases circulate and how it was discovered. Particularly the "Misconceptions" section. Also the shape of the depletion is not shuttle-sized AFAIK. Finally remind him of rain, or a house in a tornado. https://en.wikipedia.org/wiki/Ozone_depletion

Re: Ozone: The Earth's protective shield is repairing

#53

Post by jessaustin »

kevin_thibedeau wrote: post #43
Retric wrote: post #29

Earlier quoted context omitted.

Systemic corruption makes the rule of law "difficult" to enforce. And by difficult I mean this is a feature not a bug for the huge interconnected web of power that actually runs the country. PS: The fact China is not a democracy which has some unpleasant results: https://www.youtube.com/watch?v=rStL7niR7gs

All it takes is one party member (out of 80M) lodging a complaint with the central committee.

Just like USA would be a very different place if 300M people had a vote that mattered, China would be a very different place if 80M people had a complaint mechanism that mattered. We'll never hear of the city clerk who complains about the excesses of the latest giant project imposed upon local citizens. There are probably hundreds of those people, and they have all been taken care of. (Most of them in standard bureaucratic politicking fashion: "she said this terrible thing about Xi" "there is corruption in his office" etc. Kicking down is a great way to move up, when an official a couple rungs up approved the project and wants the complaints to go away.)

Re: Ozone: The Earth's protective shield is repairing

#54

Post by justinator »

barry-cotter wrote: post #49
tomerico wrote: post #23

Earlier quoted context omitted.

That's the key part. What CPC case teaches us, is that if we could find a good alternative to Fossil fuels, we could likely eliminate their use.

We have a good alternative. France produces ~80% of its electricity with nuclear power.

Transportation makes up 25% of the carbon emissions worldwide.

Cows make up like 8%.

The US military is the world's largest polluter. Most of their most serious crime against the environment is detonation of nuclear warheads.

Re: Ozone: The Earth's protective shield is repairing

#55

Post by jandrese »

sonnyblarney wrote: post #41
A2017U1 wrote: post #15

If only we could get such swift global action on greenhouse emissions. Both problems are essentially the same yet the difference in action couldn't be wider.

Tackling ozone depletion is a lot easier: we stop using some chemicals. Not a big deal. Tacking climate change is asking everyone to stop using energy (as we know it) which is fundamentally existential. They're not in the same category of proportional impact.

It's not quite that severe, but as you note the substitutes are a lot more painful than they were with CFCs. Plus the problem is much much larger. We aren't getting out of this with just a little sunburn.

Re: Ozone: The Earth's protective shield is repairing

#56

Post by atombender »

Joakal wrote: post #50
Retric wrote: post #29

Earlier quoted context omitted.

Systemic corruption makes the rule of law "difficult" to enforce. And by difficult I mean this is a feature not a bug for the huge interconnected web of power that actually runs the country. PS: The fact China is not a democracy which has some unpleasant results: https://www.youtube.com/watch?v=rStL7niR7gs

China is a democracy. https://en.m.wikipedia.org/wiki/Elections_in_China Funny thing is, people say one party system is not a democracy. What about USA's two party system? Both of them have representatives elected by people (baring the violence). But in both, people can't realistically get a new party in government, let alone run the country. Yet new parties get elected in other parts of the world, even if they don't…

The constitution defines China as "a socialist state under the people's democratic dictatorship led by the working class and based on the alliance of workers and peasants" [1]. It may be "democratic" in the sense that elections are held, but it's not a democracy in the modern sense.

[1] https://en.wikipedia.org/wiki/People's_democratic_dictatorsh...

Re: Ozone: The Earth's protective shield is repairing

#57

Post by roywiggins »

Joakal wrote: post #50
Retric wrote: post #29

Earlier quoted context omitted.

Systemic corruption makes the rule of law "difficult" to enforce. And by difficult I mean this is a feature not a bug for the huge interconnected web of power that actually runs the country. PS: The fact China is not a democracy which has some unpleasant results: https://www.youtube.com/watch?v=rStL7niR7gs

China is a democracy. https://en.m.wikipedia.org/wiki/Elections_in_China Funny thing is, people say one party system is not a democracy. What about USA's two party system? Both of them have representatives elected by people (baring the violence). But in both, people can't realistically get a new party in government, let alone run the country. Yet new parties get elected in other parts of the world, even if they don't…

Our parties change around every half century or so. The US has gone through several rearrangements of parties.

https://en.wikipedia.org/wiki/First_Party_System https://en.wikipedia.org/wiki/Second_Party_System

We're arguably currently on the sixth one.

https://en.wikipedia.org/wiki/Sixth_Party_System

Re: Ozone: The Earth's protective shield is repairing

#58

Post by justinator »

justinator wrote: post #54
barry-cotter wrote: post #49

Earlier quoted context omitted.

We have a good alternative. France produces ~80% of its electricity with nuclear power.

Transportation makes up 25% of the carbon emissions worldwide. Cows make up like 8%. The US military is the world's largest polluter. Most of their most serious crime against the environment is detonation of nuclear warheads.

Here are citations to my numbers (since I seem to be downvoted):

* Transportation: 28%

https://www.epa.gov/greenvehicles/fast-facts-transportation-...

* Livestock is 14.5% of all GHG emissions, cows are 65% of that:

http://www.fao.org/news/story/en/item/197623/icode/

* Stories on how the US Military is the world' biggest polluters:

https://www.newsweek.com/2014/07/25/us-department-defence-on...

https://www.foreignpolicyjournal.com/2009/08/15/the-worlds-w...

https://www.washingtonpost.com/opinions/america-is-the-worst...

Regarding specifically my nuclear detonation comment:

https://www.ecowatch.com/military-largest-polluter-240876060...

In addition, the U.S., which has conducted more nuclear weapons tests than all other nations combined, is also responsible for the massive amount of radiation that continues to contaminate many islands in the Pacific Ocean. The Marshall Islands, where the U.S. dropped more than sixty nuclear weapons between 1946 and 1958, are a particularly notable example. Inhabitants of the Marshall Islands and nearby Guam continue to experience an exceedingly high rate of cancer.

The American Southwest was also the site of numerous nuclear weapons tests that contaminated large swaths of land. Navajo Indian reservations have been polluted by long-abandoned uranium mines where nuclear material was obtained by U.S. military contractors.

TLDR: there's more to greenhouse gas then pollution from power plants. And nuclear power isn't problem free.

Re: Ozone: The Earth's protective shield is repairing

#59

Post by kijin »

Retra wrote: post #44
xavierstein wrote: post #30

Earlier quoted context omitted.

I guess I'm more looking for a response to "yes CFCs can destroy ozone even though they are heavier than air," and "here is a graph of the size of the ozone vs space shuttle reentries" that shows a non-correlation.

Water is heavier than air, but that doesn't stop the rain, does it?

That's not a good counterexample because rain comes down. Water vapor, which goes up, is actually lighter than air by a large margin (0.804g/L versus 1.225g/L) at the same temperature and pressure.

Re: Ozone: The Earth's protective shield is repairing

#60

Post by patrioticaction »

kaybe wrote: post #18
delibes wrote: post #3

But the BBC reported earlier this year that somebody is cheating and making CFC-11 - banned by the Montreal Protocol. https://www.bbc.co.uk/news/science-environment-44138984

It's home insulation production in China. The culprits are fully aware it's illegal, but China has some problems in getting compliance to its own laws. https://content.eia-global.org/posts/documents/000/000/761/o...

Chinese Communist Party is weak. Their authority dissolves like sugar in the face of US Dollars.
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