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#26091 05/16/08 04:33 PM
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A new NASA-led study shows that human-caused climate change has impacted a wide range of Earth's natural systems, from permafrost thawing, to plants blooming earlier across Europe, to lakes declining in productivity in Africa
Cynthia Rosenzweig of NASA's Goddard Institute for Space Science in New York, and Scientists at 10 other Institutions, analyzed a database of more than 29,000 data series pertaining to observed impacts on Earth's natural systems, collected from about 80 studies each with at least 20 years of records between 1970 and 2004. Observed impacts included changes to physical systems, such as glaciers shrinking, permafrost melting, and lakes and rivers warming. Impacts also included changes to biological systems, such as leaves unfolding and flowers blooming earlier in the spring, birds arriving earlier during migration periods, and ranges of plant and animal species moving toward the poles and higher in elevation. In aquatic environments such as oceans, lakes, and rivers, plankton and fish are shifting from cold-adapted to warm-adapted communities.

The Scientists concluded that, "Humans are influencing climate through increasing greenhouse gas emissions and the warming is causing impacts on physical and biological systems that are now attributable at the global scale and in North America, Europe, and Asia"

http://www.nasa.gov/centers/goddard/news/topstory/2008/human_impact.html


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And more...

Scientists at the Mauna Loa observatory in Hawaii say that CO2 levels in the atmosphere now stand at 387 parts per million (ppm), up almost 40% since the industrial revolution and the highest for at least the last 650,000 years.

The figures, published by the US National Oceanic and Atmospheric Administration on its website, also confirm that carbon dioxide, the chief greenhouse gas, is accumulating in the atmosphere faster than expected. The annual mean growth rate for 2007 was 2.14ppm - the fourth year in the last six to see an annual rise greater than 2ppm. From 1970 to 2000, the concentration rose by about 1.5ppm each year, but since 2000 the annual rise has leapt to an average 2.1ppm.

Scientists say the shift could indicate that the Earth is losing its natural ability to soak up billions of tonnes of CO2 each year. Climate models assume that about half our future emissions will be reabsorbed by forests and oceans, but the new figures confirm this may be too optimistic. If more of our carbon pollution stays in the atmosphere, it means emissions will have to be cut by more than is currently projected to prevent dangerous levels of global warming.

The Guardian, Tuesday May 13 2008

http://www.guardian.co.uk/environment/2008/may/13/carbonemissions.climatechange

Or, data from the horse's mouth:

Earth System Research Laboratory, Global Monitoring Division, http://www.esrl.noaa.gov/gmd/ccgg/trends/

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Thanks Mike, for the lunchtime literature.
Seems as if we're witnessing "evolution" in action.

Originally Posted By: redewenur

Scientists say the shift could indicate that the Earth is losing its natural ability to soak up billions of tonnes of CO2 each year.
Thanks Rede,
This is specifically what I've been ranting about for over a year now. "Degrading the Earth's ability to absorb CO2" is a phrase I'm sure I've written more than once. It's not our emissions that are the (main) problem; it is our rapacious behaviour towards the lands and oceans. If we managed our land and ocean resources properly, emissions would be sequestered naturally on a yearly basis (providing much of the biomass for our food and fuel). The "Turnover Rate of CO2" is not a physical constant; it is a measure of the resiliency of the biosphere.
This is why the topic of Terra Preta is so important; it provides key insights into the nature of soils ability to "soak up" CO2.

This is why changing our resource management (farming and harvesting) habits/methods is so critical to the survival of our civilization, and it's transition into a sustainable Type I civilization.
Not only does the solution multiply energy production and regulate the climate, but it also obviates poverty and other social inequities, as well as globally raise the standard of education, health care and sanitation to 'first-world' levels.
Enlisting the aid of about 4 billion marginalized people to help replenish the Earth's ability to soak up CO2 will be the quickest, easiest, and most cost effective route to evolving into a Type I, global civilization.

Restoring the planet to a natural "Eden" is not possible, but the resources are available to create a managed, equitable, sustainable, and bountiful environment.
If we're not evolving up a ladder, we're just cycling between the peaks and valleys of subsistence.
IMHO
smile


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G'day,

Wow 387 parts per million! That actually is around twenty times lower than has occurred in that not that distant past, at the time of the immediately previous Ice Age. In terms of interference with solar radiation it is actually a tiny percentage of the effects that are upon solar radiation.

Aside from anything else, there is no indication at all that shows that CO2 actually is a greehouse gas in the sense of the term being that it traps heat from the sun that otherwise would not be trapped. CO2 reacts with solar radiation only over certain quite small bands of radiation and it is not at all clear whether in that reaction the impediment to the entry of the solar radiation caused by reflection or obtuse refraction is not greater than any re-radiation or absorption of outward bound heat. Just like clouds can both heat and cool an area of the earth depending on so many factors no actually knows exactly all the factors involved, so CO2 may react the same way. If you get cloud forming in the afternoon then the evening and the next morning will be warmer than if the clouds were not there. If the clouds then stick around for three or four days then both days and nights end up being much cooler than if the clouds had not been there. Depends on the type of clouds, their internal reflectivity, whether they contain large ice formations, their height, density, colour, wind, etc, etc, etc.

So while in a laboratory you might be able to demonstrate that CO2 causes the trapping of heat the same may not be true at all in the real world and there does not seem to be any evidence to support it does at all.

This is one of those assumptions that I find most troubling with the global warming argument. It goes to the very heart of the argument yet it is perhaps the least solid theory on which the whole man made global warming argument is hung.

And even if CO2 is a greenhouse gas it certainly is no the chief one. That honour goes to water but such a huge margin, a factor of many magnitueds greater than CO2 as to be laughable. Then there is a great many other materials. Methane is around 40 times as extreme as CO2 in lab tests and there is a lot of it potentially able to be released if the frozen former marshlands in Siberia and in the oceans become released.

But it might well be that together with the methane, the effect is that more clouds form and the world cools. This is an excuse being used right now by a number of scientists to explain why nothing they said would occur in relation to global warming has come to pass. Why the oceans, especially the Pacific Ocean are COOLER even when measured over very large areas and to extreme depths. Why there has been a fall in sea levels in so many areas and no major rise in areas where they said it was certain. The argument is now going that the earth has a self regulating mechanism that they were and are unaware of that has meant that perhaps more clouds or more reflective clouds or more moisture in the air has caused the lack of warming up even when there is more heat overall. of course they then cannot actually show that there has been more heat overall but they just have to have been otherwise, well, global warming is a crock.

By the way the information you started this thread with is newspaper articles. These have been shown in this forum over and over to be biased, often misconstruing or misquoting the research involved and in this case it appears that they are not even quoting research but the opinions of some scientists.

I'm sorry but I'm guilty of the same thing in not quoting any scientific research in support of my arguments here but I'm simply not well enough to do the research and I must say that the type of research needed would be that which is basically proving a negative. That is very hard to do. So I'll turn it to a positive. Please point us to any research that demonstrates that CO2 is a greenhouse gas even if only in the laboratory and better yet to research that demonstrates that increased CO2 in the atmosphere translates to an increase in world temperature.

Please don't quote any ice core data. All ice core data is subject to considerable interpretation for starters, into such esoteric things as the leaching of air pockets, the effect on part thaw and refreeze seasonally, the possible absorption of trace chemicals, ions, gases etc from the ice to the air and on and on. But much more fundamentally there is the problem that ice cores without exception show that higher temperatures cause an increase in CO2 levels. Never the other way around. It gets hotter and then CO2 increases. Bit hard for the CO2 increase some 60 years after the heat increase to be the cause if it follows the heat and the fall back that the increase in CO2 sustains the heating does not hold true for one second. In all cases the heat seems to reduce the same basic pattern or frequency regardless of how much higher the CO2 became because of the longer hotter period. So you will have to find some other research. I'd like to help but I know of none at all that demonstrate this minor point upon which the whole man made global warming argument rests.



Regards


Richard


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Originally Posted By: RicS
Wow 387 parts per million! That actually is around twenty times lower than has occurred in that not that distant past, at the time of the immediately previous Ice Age.

What! Twenty times! Is that a transient spike, after some "big release?"
....I should go look; but first let me just say:

Ric, Ric, Ric....
You are crossing the line from being a climate-science denier into being simply a science denier.

It was observations about carbon dioxide's "greenhouse effect" that led into the science of spectroscopy, and also evolving models of the atom that could explain spectroscopic observations.
You are questioning work done back in the 19th century by names such as Fourier, Angstrom, and Roentgen.
For a brief history, with modern updates, google Arrhenius & carbonic acid; or see:
http://www.aip.org/history/climate/co2.htm
That's the American Institute of Physics, isn't it?

I think this link will answer your request for an experiment on CO2.
http://earthobservatory.nasa.gov/Library/Giants/Tyndall/

Note the strong CO2 absorbance (dip) between 4-5 microns (where water does NOT absorb much). ...hence the logic problems arising as some simply say 'water vapor is a stronger GHG than CO2.'

smile

Last edited by samwik; 05/18/08 07:11 PM. Reason: repeated link

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Interesting......

Quote:
Cynthia Rosenzweig of NASA's Goddard Institute for Space Science in New York and scientists at 10 other institutions have linked physical and biological impacts since 1970 with rises in temperatures during that period


So they've correlated ecological impacts to observed warming since the 1970's.....Assumed that all that warming is due to AGW, and somehow this "proves" that AGW is to blame for the ecological impacts? This is science?

I'm going to release a study outlining the effects of AGW on the world pirate population. Pirate population since 1850 has been in steep decline. The world has warmed since 1850. The warming is caused by AGW. Therefore AGW causes a decline in pirates. AGW is a good thing.
Can I get a grant now??


This quote is also interesting
Quote:
Other driving forces, such as land use change from forest to agriculture, were ruled out as having significant influence on the observed impacts.


I'd be interested to see how they controlled for all other impacts us humans have, other than CO2 emissions. I don't know too many locales that we haven't screwed up, in one form or another.

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Originally Posted By: samwik


Note the strong CO2 absorbance (dip) between 4-5 microns (where water does NOT absorb much). ...hence the logic problems arising as some simply say 'water vapor is a stronger GHG than CO2.'

smile


samwik - sorry, water vapour is a stronger GHG than CO2. Just looking at the GCM output should drive that home. At 2xCO2, warming effects are estimated to be about 1.1C. It is the positive feedback processes (namely the increase in water vapour) that brings the total warming effect to be 2.5-4 degrees.

Also, the warming effect caused by CO2 increases logarithmically. This is due to IR at the CO2 absorption band already being removed to extinction (can't absorb what's not there). It is theorized that at lower pressures (higher elevations), the absorption band for CO2 will broaden, which will allow more IR to be absorbed, which is where this extra warming is supposed to happen. This is why we're supposed to see more warming at the mid-troposphere, than the lower troposphere. Yet, we see the exact opposite......apparently another "fingerprint" we're not seeing.

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Yes, your first paragraph is completely true. H2O is stronger (there's more of it and it absorbs over a wider range of wavelengths), but it does not absorb where CO2 absorbs (between 4-5 microns); hence the "strength" of the two is unrelated in terms of IR absorbance (apples and oranges logic).

But what the heck is your second paragraph talking about?
Extinction? At atmospheric pressure ranges? Where did you get this from?
The blackbody radiation from Earth (at 4-5 microns) far outstrips the capacity for CO2 to absorb it all (until our atmosphere gets up to >85% CO2). smile

Originally Posted By: Canuk
It is theorized that at lower pressures (higher elevations), the absorption band for CO2 will broaden, which will allow more IR to be absorbed....
What new physics is this? They've already tested gasses at different pressures. Absorbance spectra don't broaden or narrow until you start changing phase to a liquid or solid. Where did you get this info. from?

I think it's emission spectra that change with pressure.
Standard physics tells us that at lower pressures, CO2 can radiate heat away (to space) more easily, as at these lower pressures, there are fewer collisions to translate (retaining) the heat, and there is less chance of another molecule re-absorbing any released IR. Maybe we're talking about different layers of the atmosphere here, but the "physics" that I know predicts higher concentrations of CO2 will increase cooling in the upper levels (lower pressure levels) of the atmosphere.

Maybe we're both wrong (it's been 30 years since I took classes in this stuff), or maybe we're both right and just not expressing it very well; but I'd like to find out whether you know this physics yourself or if you've learned this stuff second hand (and where can I learn more of it)?
wink


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Infrared radiation is absorbed then remitted. It does not contribute to the kinetic energy of the molecule, so it does not contribute to a rise in air temperature. Physicist R.W. Wood demonstrated in 1909 that greenhouses didn't become warmer by trapping IR radiation.

http://www.wmconnolley.org.uk/sci/wood_rw.1909.html

The small frequency band that CO2 absorbs combined with the small 0.0387% of the atmosphere that CO2 takes up leaves little radiation for the CO2 molecules to reflect back to earth.

John M Reynolds

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John,

Oh, I think I see your logic; there's no net change after the IR is re-emitted, therefore no heating? Where do you think it goes?

I wrote this below, after first reading your post. After re-reading, the below still applies, and explains the heating of the atmosphere, even if the CO2 has no net change (really it's in an equilibrium, between having absorbed some IR and having re-emitted some IR; there's no final, net, state).

So, initially, in response to your post....
Even if IR did not contribute to "kinetic energy" (via collisions you mean?), the re-emitted radiation does get absorbed by other air molecules frequently enough to "contribute to a rise in air temperature." But CO2, energized by IR absorbance, can also translate that extra heat to other air molecules, via collisions.

Perhaps, when you say, "does not contribute to the kinetic energy of the molecule," you are referring to the rotational and stretching vibrational modes for CO2. These could be considered as "potential energy;" but in the long run, that energy is either re-emitted as IR, or lost through collisions (kinetically, just as with any gas molecule).

Originally Posted By: JMR
The small frequency band that CO2 absorbs combined with the small 0.0387% of the atmosphere that CO2 takes up, leaves little radiation for the CO2 molecules to reflect back to earth.
...or 'leaves little radiation for the CO2 molecules to absorb and then reflect back to earth (or other molecules).'

Anyway, yes; that a fair qualitative assessment.
Quantitatively however, one needs to realize that losing all the water vapor in the atmosphere would change things by 70-100 degrees (cooler); whereas losing all the CO2 in the atmosphere would only drop the temperature by about 5-10 degrees. Conversely, doubling or tripling the CO2 would only add 5-10 degrees.

Just to be clear, when you say "leaves little radiation," it's important to realize that there is lots of heat at 4-5 microns, as well as more at the shorter wavelengths. There's no danger of "running out of 4-5 micron radiation" for CO2 to absorb or "reflect."

As to the link.... Hey!
This link has nothing to do with what we're talking about here.

It doesn't even mention, much less test, CO2!
It only deals with the greenhouse effect of glass. The substances, glass and CO2 (& as noted, along with rock-salt) all behave differently in response to solar radiation.
...and, as the original poster noted, the conclusions are wrong.
~SA


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What are you talking about Samwik? My link deals with the greenhouse effect of IR radiation. It is suggsted that if you increase the level of CO2 in a greenhouse, that the temperature would increase by slowing the rate at which IR can leave the structure. Similarly, if you keep the CO2 at the same level and only increase the amount of IR radiation, then the temp would still increase. The link I gave you disputes the second with respect to air, so logically it also disputes the first. That is not how greenhouses work.

Temperature is the measure of kinetic energy of atoms and molecules. Since IR does not contribute to to the temperature of air, it also does not contribute to the kinetic energy of molecules.

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Hi John,

I'm gonna start at the end, and work backwards.
"Since IR does not contribute to to the temperature of air...." -JMR
Okay, I guess you mean that the oxygen/nitrogen part of our atmosphere is transparent to IR. That is true.

"...it also does not contribute to the kinetic energy of molecules. " -JMR
Ever? smile Not even CO2 (which then itself, heats the air)?

I'm not sure how to take this. You've mentioned "kinetic energy" before, and I provided some information about your use of the phrase, which should have precluded this most recent remark.

If you're considering kinetic energy only as "translational vibration" (moving from one place to another and bumping into things), then you're missing all the "rotational" and "stretching" vibrational modes that gas molecules have. It is these vibrations that are equated with CO2's absorbed IR at 4-5 microns.
Eventually, if these vibrations are not transmitted to another air molecule (by bumping it), the vibrational energy will be re-emitted (to be re-absorbed locally, if not escaping unimpeded into space).

Maybe there should be a thread on "Energy, kinetic and potential." Does the above make sense?

So, with this understanding of "kinetic energy," yes; your statement "Temperature is the measure of kinetic energy of atoms and molecules," is true.

Have you read somewhere that IR (4-100 microns) does not contribute to the kinetic energy of air, or CO2, or any gas molecule?
I'd like to see such a link....
===

Okay, now on that first paragraph, about the greenhouse stuff....
Firstly, there's a big difference between the effect of a glass greenhouse, and CO2's "greenhouse effect."
They are analogous, but not the same; not even similar in their mechanism of heating action, as glass is opaque to IR, and CO2 is nearly invisible (except at 4-5 microns and above 13 microns).

Secondly, when you say, "It is suggsted that if you increase the level of CO2 in a greenhouse...." are you talking about CO2 inside of a glass structure?
If so, why; there nothing about it in that link, nor is there any real-world analog in our climate.
I'm not trying to be obtuse, but that was all I could get out of that first paragraph; you actually use the word 'structure' in that sentence about CO2.

Thirdly, do you have any other link(s) about this? Your link to a blog about a century old article in which the author himself, after making some comparative observations in his garden, concludes with:
"I do not pretent to have gone very deeply into the matter, and publish this note merely to draw attention to the fact that trapped radiation appears to play but a very small part in the actual cases...." -R. W. Wood [final paragraph]
...and the OP goes on to say,
"I present the full text, although the second-to-last paragraph is (in my opinion) regrettable and wrong." -link

...again, there's nothing about CO2 on this 1909 link of yours.
...and that American Institute of Physics link does have all these common misunderstandings spelled out and answered.

...any questions? I'll be happy to answer....

...also, just fyi....


You asked, what I am talking about?
It's been 25 years since my degree in Chemistry, but I don't think the principles of physical chemistry or instrumental analysis have changed too much. I may be wrong about something or, more likely, I left something out; but I'm pretty sure the end result is correct.
Are there any chemists or physicists who think CO2 doesn't absorb IR as the spectra show?

Well, this is way too much talking (although shorter than the average college lecture); but this is a complicated subject (they pay people to teach this stuff, y'know), so it shouldn't be too surprising.
smile
~SA


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You are doing a poor job of fisking Samwik. The way we tell the globe is warming is by taking the temperature of the air. In the Wood experiment, he used air as the medium. One of the boxes was encased in a material that blocked IR radiation. The other was encased in a material that permitted IR radiation to pass through to do what it could to the water vapour, CO2, methane, ozone, etc. that was in the box. There was virtually no difference in the temperature of the two boxes, so the answer to your "Not even CO2" question is Yes. Not even CO2 nor the more powerful water vapour that existed in the air changed the temperature of the polished rock salt box.

The rest of your post is about strawman arguments like your "[a]re there any chemists or physicists who think CO2 doesn't absorb IR as the spectra show" question. I am not saying that the IR is not absorbed. You are confusing the two arguments.

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Oh, ...so it's not me that's trying to be obtuse.

Score one for a casual observation in 1909; and zero for the accumulation of atomic theory and spectroscopic science in the 20th century.
My apologies; we must be wrong about all this science stuff.

Originally Posted By: JMR
I am not saying that the IR is not absorbed. You are confusing the two arguments.

Please, help me learn; what two arguments am I confusing?
smile


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There are two hypotheses:

1. The absorption of IR radiation by molecules in the air does not contribute to the temperature of the air.

2. IR radiation is absorbed by some molecules in the air.

You are busy refuting the second when that is not what the Woods experiment found.

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Hi John, Thanks for the clarification.

Hypotheses (not arguments)?

Aren't physical chemistry and spectroscopy sufficiently advanced to be beyond the need of hypotheses about basic physical processes like these?

I'm not trying to "refute" anything, except maybe that Woods' observations with glass and rock salt don't qualify as "an experiment" (certainly not about CO2 or physics in general); I'm saying that IR "is absorbed by some molecules in the air," and so are you:
Originally Posted By: JMR
I am not saying that the IR is not absorbed.

So, on #2 we seem to agree.
===

Now I will try to refute your hypothesis #1.
Who came up with this hypothesis?

Wouldn't this be an example of an action without an "equal reaction?"
Originally Posted By: JMR
1. The absorption of IR radiation by molecules in the air does not contribute to the temperature of the air.
What does the absorption of IR do to molecules in the air?
smile
Thanks~



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The IR is absorbed then re-emitted.

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I was going to edit my previous post and also ask "what does heat up the air?"

Originally Posted By: John M Reynolds
The IR is absorbed then re-emitted.


So, then what happens to the IR, after it's re-emitted?


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It is absorbed by another molecule or exit the box.

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Originally Posted By: John M Reynolds
It is absorbed by another molecule or exit the box.


Well, I guess I agree with that. If not exiting, isn't being "absorbed by another molecule," heating that molecule up?
Do you not consider "absorbing IR" and "heating up" to be the same thing?

Originally Posted By: JMR
1. The absorption of IR radiation by molecules in the air does not contribute to the temperature of the air.

I guess the question needs to be "what does heat up the air?"

...also, what does the infra-red radiation do after it's absorbed, while it's waiting to be re-emitted?

This is getting interesting; thanks again John.
~samwik
smile


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