Greenland ice cores show industrial record of acid rain, success of US Clean Air Act

Apr 11, 2014
This shows ice core drilling at Summit, Greenland in June 2007. Credit: Joel Savarino / Laboratory of Glaciology and Geophysics of the Environment (LGGE)

The rise and fall of acid rain is a global experiment whose results are preserved in the geologic record.

By analyzing samples from the Greenland ice sheet, University of Washington atmospheric scientists found clear evidence of the U.S. Clean Air Act. They also discovered a link between acidity and how nitrogen is preserved in layers of snow, according to a paper published this week in the Proceedings of the National Academy of Sciences.

Forty-five years ago, was killing fish and dissolving stone monuments on the East Coast. Air pollution rose beginning with the Industrial Revolution and started to improve when the U.S. Clean Air Act of 1970 required coal power plants and other polluters to scrub sulfur out of their smokestacks.

UW researchers began their study of ice cores interested in smog, not acid rain. They discovered a link between the two forms of pollution in the geologic record.

Nitrogen is emitted as a short-lived compound, NOx, which causes ground-level ozone, the main ingredient in smog, and relates to compounds that are the "detergent" of the atmosphere. Sources of NOx include smokestacks and vehicle tailpipes, as well as wildfires, soil microbes or reactions triggered by lightning strikes.

Teasing out the sources of NOx through history might tell us about the atmosphere of the past, how methane, ozone and other chemicals change in the atmosphere, and also provide a measure of global human emissions.

South Dakota State University's Jihong Cole-Dai is logging an ice-core sample at Summit, Greenland. Credit: Joel Savarino, Laboratory of Glaciology and Geophysics of the Environment (LGGE)

"How much the in ice core records can tell about NOx and the chemistry in the past atmosphere is a longstanding question in the ice-core community," said lead author Lei Geng, a UW postdoctoral researcher in atmospheric sciences.

Unlike other gases, short-lived NOx can't be measured directly from air bubbles trapped in ice cores. Within a day or two most of the NOx changes into , a water-soluble molecule essential to life that gets deposited in soil and snow.

Earlier research by co-author Eric Steig, a UW professor of Earth and space sciences, suggested that comparing amounts of the two stable forms of nitrogen – nitrogen-15 and nitrogen-14 – in nitrate could pinpoint the emission sources of NOx. Ice cores from Greenland and North American lake sediments showed the nitrogen-15 ratio gradually decreasing since 1850, suggesting a corresponding rise in human emissions.

The new research says: not so fast. The detailed measurements of nitrate, NOx and sulfur show the nitrogen isotope ratio leveling off in 1970, and suggests that ratio is sensitive to the same chemicals that cause acid rain.

"This shows that the relationship between emissions and the isotopes is less direct than we thought, and the final signal recorded in the Greenland ice cores is actually not just the nitrogen emission, but the combined effect of sulfur and nitrogen emissions," Steig said.

The ice cores used in the study were collected in 2007 at Summit Station, Greenland. Total amounts of nitrate for each year were measured and calculated at South Dakota State University, where Geng did his doctoral work. The different forms, or isotopes, were measured in UW's IsoLab. Geng's work showed that the long-term decrease in the nitrogen-15 isotope since 1850, and its leveling off in 1970, are linked to changes in air chemistry. Airborne nitrate can exist as a gas or a particle, and nitrate with lighter isotopes tends to exist as a gas. But he found that the total fraction of nitrate present as gas or particle varies with the acidity of the atmosphere, and the acidic air causes more of the light isotopes to exist as a gas.

"The isotope records really closely follow the atmospheric acidity trends," said co-author Becky Alexander, a UW associate professor of atmospheric sciences. "You can really see the effect of the Clean Air Act in 1970, which had the most dramatic impact on emission of acid from coal-fired power plants."

What's more, airborne nitrate dissolves in water and falls at the poles as snow. While that snow sits on the ground, sunlight bouncing off the surface triggers chemical reactions that send some of it back into a gas form. Acid air can also influence the reactivity of nitrate in snow and thus the preservation of nitrate in ice cores.

Other ice core records might also be affected by acidity in air, Alexander said. No effect would be expected for stable gases like carbon dioxide and oxygen, or for the water molecules used to calculate temperature variations through time. But acidity in air could influence deposition and preservation of other volatile compounds such as chlorine, mercury or organic materials in ice cores.

Eventually, better understanding of the air chemistry during formation of the layers could allow researchers to correct for the effect, extracting better information of the past from these compounds in the .

Explore further: Cooperative SO2 and NOx aerosol formation in haze pollution

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User comments : 29

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Shootist
3.8 / 5 (4) Apr 11, 2014
You don't need Ice Cores to see the success. Just look to the pH levels of eastern Canadian lakes.
The Alchemist
4.3 / 5 (3) Apr 11, 2014
How do we keep good legislation up? Great job!
Shootist
2.3 / 5 (6) Apr 11, 2014
How do we keep good legislation up? Great job!


Well, it isn't terribly good legislation however, it does manage to have some of the intended results.

The law is too restrictive on private automobiles. They contribute less than 10% of total air pollutants, yet are targeted for extinction, while less well known but, much more egregious, sources of air pollution go unregulated or unnoticed.
antialias_physorg
4.4 / 5 (7) Apr 11, 2014
The law is too restrictive on private automobiles. They contribute less than 10% of air pollutants, yet are targeted for extinction

Do you have the feeling there are less automobiles? According to what I find the number of automobiles has steadily risen since the 60's to the point where there is almost one per man, woman and child in the US nowadays.

I don't know about you, but 'extinction' is not the word I'd use for that. Maybe you were looking for 'explosion'?
Modernmystic
2 / 5 (2) Apr 11, 2014
Air pollution rose beginning with the Industrial Revolution and started to improve when the U.S. Clean Air Act of 1970 required coal power plants and other polluters to scrub sulfur out of their smokestacks.


Correction. Air pollution rose beginning with the Industrial Revolution and started to improve LONG before the U.S. Clean Air Act. It had been improving for decades before that. The Clean Air Act accelerated the process...
Modernmystic
2.5 / 5 (2) Apr 11, 2014
The law is too restrictive on private automobiles. They contribute less than 10% of air pollutants, yet are targeted for extinction

Do you have the feeling there are less automobiles? According to what I find the number of automobiles has steadily risen since the 60's to the point where there is almost one per man, woman and child in the US nowadays.

I don't know about you, but 'extinction' is not the word I'd use for that. Maybe you were looking for 'explosion'?


Given all of that, what do you think the likelihood of Americans surrendering their cars is? Give me an honest answer to that question. I'm not looking to pick a fight, I just want to know your opinion and the point of the comment.
antialias_physorg
5 / 5 (4) Apr 11, 2014
Given all of that, what do you think the likelihood of Americans surrendering their cars is?

None. Why should they? But cars do age and in ten years most of those will have to be replaced. If by then cleaner and cheaper alternatives are available then there is no reason why anyone would have to miss mobility. Since gas prices can only go up and electricity prices can only go down 8especially at pek hours of production for renewables) you can do the math yourself when that time will be. Car manufacturers just need to hop on the bandwagon and stop doing these half assed EVs based on combustion car stock parts.

I really see no 'threat' to anyone's way of life, here. (Even if that were so: driving is a privilege, not a right - that's why licenses are issued, not granted at birth)
Modernmystic
3 / 5 (2) Apr 11, 2014
If by then cleaner and cheaper alternatives are available then there is no reason why anyone would have to miss mobility.


So long as they are affordable, capable, and fit the culture (ie wide open spaces vs. the closeness of Europe) I completely agree.

I really see no 'threat' to anyone's way of life, here. (Even if that were so: driving is a privilege, not a right - that's why licenses are issued, not granted at birth)


Actually it completely depends on your culture as to whether or not it's a privilege or a right. Your or my views/moralizing are completely irrelevant on that point unless we convince the larger culture at large otherwise.

That being said I know of no culture where it is considered a right. However, as technology advances and as luxuries become "needs" in order to function in a highly mobile and advanced society I can absolutely see it becoming a right in future cultures and societies.
antialias_physorg
4.8 / 5 (4) Apr 11, 2014
It can't be a right since you aren't given the means for free. You have to pay (for the car, for gas, for insurance), and you have to get a license.

You have the freedom to drive if (and only if) you can afford all of the above. If it were a right then it would be accorded to everyone by law regardless of whether they can afford to or pass the test.

And with the increasing virtualisation of the world the need for mobility will probably dwindle in the future in any case.
rockwolf1000
2 / 5 (2) Apr 11, 2014
[q
I really see no 'threat' to anyone's way of life, here. (Even if that were so: driving is a privilege, not a right - that's why licenses are issued, not granted at birth)

I take issue with this point.
A person who lives in a free society should have the right to move about from point A to point B. Are you suggesting they only have that right if they walk there? Would they have the right to move about via; bicycle, skateboard, roller skates, pogo stick? At what point does the right to move about become a privilege? Once a person uses a device other than their feet? Perhaps the addition of wheels? Maybe it's a motor or engine? Where exactly is the line drawn? Should we just be content with the notion that the government says it's a privilege and that's final. Keep in mind my tax dollars help pay for the roads, thus I partially own, and have a right to access and utilize them.
Modernmystic
1 / 5 (1) Apr 11, 2014
It can't be a right since you aren't given the means for free.


Were you given the ability to read "for free"? What about speak? You had to pass tests in school on both points. Should that interfere with your right to say what you think or read what you will?

In my culture I have a right to own a firearm...those are NOT free :)

Your definition here is far too narrow. I appreciate it's your position, but it's not tenable and certainly not universally applicable.

And with the increasing virtualisation of the world the need for mobility will probably dwindle in the future in any case.


Perhaps, who can say? It's a fair point in any case.
antialias_physorg
5 / 5 (3) Apr 11, 2014
A person who lives in a free society should have the right to move about from point A to point B. Are you suggesting they only have that right if they walk there?

You think the nation should provide you the means for free?
That would be *gasp* socialism.

Take the bus, take the train, take a plane, take a taxi, ride a bike. Those not enough options for you? Where does it say: Every person in the nation shall be provided with an automobile?
In case you haven't noticed: Vehicle traffic is the MOST regulated sector in any nation. It has the most laws. By far.

Keep in mind my tax dollars help pay for the roads, thus I partially own, and have a right to access and utilize them.

Your tax dollars also pay for nukes. You're not given the keys to those (nor are given right to demand them). Your tax dollars pay for all kinds of things you have to pay for to use (powerplants, water supply, ... )
antialias_physorg
5 / 5 (2) Apr 11, 2014
In my culture I have a right to own a firearm...those are NOT free

Yep, you have that - because some idiot wrote it into some document. However that same document says very little about automobiles or personal mobility (at least last I read it).
foolspoo
3 / 5 (1) Apr 11, 2014
The law is too restrictive on private automobiles. They contribute less than 10% of air pollutants, yet are targeted for extinction

Do you have the feeling there are less automobiles? According to what I find the number of automobiles has steadily risen since the 60's to the point where there is almost one per man, woman and child in the US nowadays.

I don't know about you, but 'extinction' is not the word I'd use for that. Maybe you were looking for 'explosion'?


embarrassing... Energy production and consumption for industrial and commercial facilities has a far bigger affect on our environment than our transportation. but its cool, you see disagreement and you become no better than the ones you put down.
rockwolf1000
1.5 / 5 (2) Apr 11, 2014
A person who lives in a free society should have the right to move about from point A to point B. Are you suggesting they only have that right if they walk there?

You think the nation should provide you the means for free?
That would be *gasp* socialism.


No. I'm asking. If I build a locomotion machine of some sort, do I not inherently have the right to use it to get from where I'm at to where I need to be? Or do I need some sort of permission from an "authority"? Are you suggesting that unless I walk, I only have the right to stand in one spot and not move? I understand and support regulations in vehicular transportation. Without it chaos would ensue. See road fatality rates in Pakistan, India etc. This doesn't mean I don't consider it my right to move about. Walking or otherwise.
Modernmystic
3 / 5 (1) Apr 11, 2014
In my culture I have a right to own a firearm...those are NOT free

Yep, you have that - because some idiot wrote it into some document. However that same document says very little about automobiles or personal mobility (at least last I read it).


Some idiot wrote it in a document? Well that tells me a little more about you :)

The point is that I have that because my culture and society say I do, and moreover uphold and enforce it. It's just that simple. Your philosophical arguments and values just simply aren't relevant to the situation. It's not a slight to you that they aren't, it's just a simple fact.

The fact that the document doesn't say anything about automobiles may simply be because it was written before they were invented and an integral part of society. The one thing I'm absolutely sure of is that the reason it isn't there has nothing to do with your personal feelings on the subject :)
Captain Stumpy
4.5 / 5 (2) Apr 11, 2014
Actually it completely depends on your culture as to whether or not it's a privilege or a right.
@Modernmystic
ya may want to clarify this a bit... it is a right to have freedom of movement, but it is a privilege to drive, and this I spelled out quite clearly in US law, as well as most other places that I have seen. just sayin...
A person who lives in a free society should have the right to move about from point A to point B. Are you suggesting they only have that right if they walk there?
@rockwolf1000
IIRC, you have the right to be mobile as long as the motor is under 90cc's (which does not have to be licensed) or under a certain rating for electric motors

the US (and most other places I've been) driving license are given as a privilege, not a right. the right to freedom of movement does not guarantee the right to drive a motor vehicle. although it does not rule out other modes of transport like horseback/buggy etc. Flight/boating is privilege as well within US borders
Captain Stumpy
5 / 5 (3) Apr 11, 2014
No. I'm asking. If I build a locomotion machine of some sort, do I not inherently have the right to use it to get from where I'm at to where I need to be? Or do I need some sort of permission from an "authority"?
@Rockwolf
no, you dont have the RIGHT to use it on US roads unless it is DOT compliant, taxes are paid etc... UNLESS it is below a certain CC (for gas motors) or rating (for electric motors), and then there are certain requirements to make it "road legal"

DOT web site should cover this, or you can talk to your local law enforcement/licensing office.

rockwolf1000
4 / 5 (1) Apr 11, 2014
No. I'm asking. If I build a locomotion machine of some sort, do I not inherently have the right to use it to get from where I'm at to where I need to be? Or do I need some sort of permission from an "authority"?
@Rockwolf
no, you dont have the RIGHT to use it on US roads unless it is DOT compliant, taxes are paid etc... UNLESS it is below a certain CC (for gas motors) or rating (for electric motors), and then there are certain requirements to make it "road legal"

DOT web site should cover this, or you can talk to your local law enforcement/licensing office.


I disagree, I have the right to use it. Subject to agreed upon conditions which were generally initiated via public concern. You an A_P are both making the false assumption that I'm only talking about moving about on public roads. The question was: Do I have the right to move about on an apparatus other than my feet?
Captain Stumpy
5 / 5 (2) Apr 11, 2014
You an A_P are both making the false assumption that I'm only talking about moving about on public roads. The question was: Do I have the right to move about on an apparatus other than my feet?
not trying to pick a fight, just telling you what I learned from the DOT/talking to the local law enforcement.

IF you are a US citizen:
you have the right to move about freely, however, when you start adding mechanized assistance in the form of engines, electric or fuel, it is regulated, and no longer is a right, but a privilege, per the law. so the "apparatus other than your feet" is entirely dependent upon what the DOT/laws spell out.
you CAN use assistance (like a horse or bike) and it is your RIGHT to move about freely, but not on (all) public roads with (any) motorized vehicles. that is regulated and considered a privilege.

for further information I recommend a legal website or talking to your local DOT/law enforcement. this is just what they told me.

Modernmystic
5 / 5 (1) Apr 11, 2014
ya may want to clarify this a bit... it is a right to have freedom of movement, but it is a privilege to drive, and this I spelled out quite clearly in US law, as well as most other places that I have seen. just sayin...


Sure. I've never seen the right to drive in any human society that I know of. It's always quite clearly a privilege. I'm not saying I actually have the right. I'm saying that there is nothing to preclude this possibility. It's not like an immutable law of physics. Whether or not driving is a right or a privilege is ENTIRELY up to the society in question and there is no "law of philosophy or politics" which could preclude someone making it a right.

Does that make my position more clear?
rockwolf1000
4.5 / 5 (2) Apr 11, 2014
@ CS - A_P
not trying to pick a fight, just telling you what I learned from the DOT/talking to the local law enforcement.

Haha. Me either. Just trying to have an interesting discussion with a pair of very intelligent fellows. Do continue.
Rights are sometimes regulated for the benefit of society. For instance: Everyone has the right to have sex with a consenting partner. However, we have "age of consent laws" to protect younger members of society from becoming victims. Therefore we as a society sometimes withhold a persons rights until a certain threshold is met ie. minimum age, demonstrated competence, etc. A person can also have their rights revoked if they demonstrate a threat to public safety. i.e. prisons. My point is simply that I think it is very dangerous to label basic survival requirements as privileges. Example: the right to move about in home made cars powered by tightly wound rubber bands for instance.
Captain Stumpy
4.7 / 5 (3) Apr 11, 2014
My point is simply that I think it is very dangerous to label basic survival requirements as privileges
I can totally agree with that!

you would be surprised how many "rights" really aren't rights... take your example of sex with consenting partners: there are a lot of blue laws still on the books. they are not enforceable, BUT they are used when an offender commits an act like rape/etc. (like laws against anal sex, oral sex etc)

personally, I don't like a lot of laws. especially ones that don't make sense (at least to me)...

interesting looking at other countries and how they view is though

right AA_P? (what are ya? Brit? Aussie? Canadian? Deutch? Tsalagi? just wondering...)
antialias_physorg
5 / 5 (3) Apr 11, 2014
If I build a locomotion machine of some sort, do I not inherently have the right to use it to get from where I'm at to where I need to be?

Sure. Why not? Unless you break any laws in the process there's nothing against that. What I'm saying is: You have no way to sue the government to move you about if you can't afford anything other than walking. If walking is all you can afford - then walking is what you'll have to do. Roads are provided for your use. (But if the government would close those for, say, all but military traffic tomorrow then you'd be out of luck. You cannot DEMAND roads be put down for you)
Are you suggesting that unless I walk, I only have the right to stand in one spot and not move?

This might go against the pursuit of happiness (hard to do if you can't move).

But I think we're arguing past each other. A privilege is something given. A right is innate. Roads, licenses are given. Buy a car (and no license) and see how far you get demanding your right.
antialias_physorg
5 / 5 (5) Apr 11, 2014
My point is simply that I think it is very dangerous to label basic survival requirements as privileges

That's why they're called human rights (and not human privileges). Privileges (like a drivers license) can be taken away. Rights (like the right to a fair trial) cannot.

...erm...Ok that last one was a bad example in the light of the events of the past years (or the past centuries). Some countries are sneaky in twisting definitions until rights become privileges which can be revoked (soldiers become 'combatants' to deprive them of the rights accorded by the Geneva convention. Humans beome redefined as 'subhuman' to deprive them of any kind of human rights, etc.).

right AA_P? (what are ya?

German
Agomemnon
1 / 5 (3) Apr 13, 2014
The real clean air act has been met and succeeded.
Since they don't want to lose their cushy government job with good healthcare (unlike Obamacare) and taxpayer supported pensions - they decided to sue that CO2 (plant nutrient and trace gas) is pollution when it isn't.

In the meantime the EPA has increased the alloweable amount of glyphosate (roundup to you and me) a endrocrine disrupter, cancer causing toxin that can now be found in human mothers breast milk and the placenta of the unborn babies.
But never mind that...poison every man women and child with this crap but as long as we attack coal companies....it all makes up for it. Yeah Right. Frauds!
Captain Stumpy
not rated yet Apr 14, 2014
@antialias_physorg
Ich spreche nicht Deutsch, aber ich für eine Zeit in Kaiserslautern gelebt und Würzburg. Ich liebte Gemany, epecially das Bier und die Mosel Weine.
Wo in Deutschland leben Sie? Ich habe alle überfahren, und verwendet werden, um in der Feuerwehr, die auch außerhalb des Autobahn 6 Vogelweh coered zu arbeiten.

PEACE
Maggnus
5 / 5 (1) Apr 14, 2014
You don't need Ice Cores to see the success. Just look to the pH levels of eastern Canadian lakes.
Oh, Dyson agrees with this then? So acidic rain is ok, but co2 derived global warming isn't?

The law is too restrictive on private automobiles. They contribute less than 10% of total air pollutants, yet are targeted for extinction, while less well known but, much more egregious, sources of air pollution go unregulated or unnoticed.


Do you find that your duplicity affects how you see yourself in the mirror?
Maggnus
5 / 5 (1) Apr 14, 2014
No. I'm asking. If I build a locomotion machine of some sort, do I not inherently have the right to use it to get from where I'm at to where I need to be? Or do I need some sort of permission from an "authority"?
Whoa. Actually no, you don't have the inherent right to use it, and yes, you do need some sort of permission - just ask the people who have invented flying cars.
Are you suggesting that unless I walk, I only have the right to stand in one spot and not move?
That's a pretty extreme and unrealistic example.
I understand and support regulations in vehicular transportation. Without it chaos would ensue. See road fatality rates in Pakistan, India etc. This doesn't mean I don't consider it my right to move about. Walking or otherwise.
Of course you have the right to move about. That doesn't mean you have to right to move about while putting my life in danger. You are arguing using the position of a false dilemma .