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Global temperatures correlated with CO2 rise?

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Wild Cobra

Posted: Sat May 22, 2010 5:50 pm Post subject:

Forum Ph.D.

Joined: 01 Sep 2009
Posts: 927

Twit of wit wrote:

Wild Cobra wrote:

Topalk wrote:

marnixR wrote:

correct if i'm wrong, but i thought the OP was referring to whether an increased CO2 content in the atmosphere leads to an increased absorption rate in the oceans or not

no CO2 makes the ocean more acidic

Have you by chance done the math on that to see how much of a CO2 change is needed for a 0.1 PH change?

Ocean acidification is ongoing and well measured, so what is your point?

How much of the acidity change is due to CO2/carbonic acid vs. other factors. Problem with those on the AGW side is they make everyone assume that CO2 is the only cause for things we see negative. It isn't.

I won't attempt to show what else changes ocean acidity. However, before you blame CO2, I suggest you understand just how large an ionic change it takes to change the PH. There are those out there attempting to blame CO2 for a 0.6 PH increase over I think a decade. I forget the details, old news. I also forget the exact relationship between absorbed CO2 and ionic changes. If it's 1:1, then at equilibrium, the increased CO2 by 30% would be a 0.1 PH increase. If 1:1 is the relationship, it would take a 4x increase of CO2 to increase the PH by 0.6.
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Lynx_Fox

Posted: Sat May 22, 2010 6:18 pm Post subject:

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Location: Washington State

Wild Cobra wrote:

There are those out there attempting to blame CO2 for a 0.6 PH increase over I think a decade. I forget the details, old news. I also forget the exact relationship between absorbed CO2 and ionic changes. If it's 1:1, then at equilibrium, the increased CO2 by 30% would be a 0.1 PH increase. If 1:1 is the relationship, it would take a 4x increase of CO2 to increase the PH by 0.6.

Ph decreases with increased acidity.

The measured change for the worlds ocean's surface waters has been about 0.1 PH decrease since the start of industrial revolution.

The only studies I've seen suggesting a 0.6 PH decrease are worst case ones that projections over the next few centuries and assume we're stupid enough to burn and release the entire load of fossil carbon.

There is considerable concern and uncertainty as to the effects of lowering PH by another 0.1 or 0.2 that looks quite likely in our lifetimes.
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inow

Posted: Sat May 22, 2010 6:22 pm Post subject:

Forum Professor

Joined: 04 Oct 2009
Posts: 1848
Location: Austin, TX

Wild Cobra wrote:

Problem with those on the AGW side is...

Warning... warning... warning... A strawman is imminent... warning... warning... warning...

Wild Cobra wrote:

they make everyone assume that CO2 is the only cause for things we see negative.

Yep. There it is.

Wild Cobra wrote:

I won't attempt to show what else changes ocean acidity.

Of course, you won't. Everyone knows there are other factors to consider in ocean acidification and that CO2 is only one... although, a very prominent one. You're trying to imply that those factors are the key ones in the current trend, and that CO2 is not.

Run the numbers. It might be nice to see you realize how much of a role CO2 really plays.
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Wild Cobra

Posted: Sat May 22, 2010 10:12 pm Post subject:

Forum Ph.D.

Joined: 01 Sep 2009
Posts: 927

Lynx_Fox wrote:

Wild Cobra wrote:

Ph decreases with increased acidity.

True. I have no idea why I missed that. That goes past what my dyslexia sometimes does.

Lynx_Fox wrote:

The measured change for the worlds ocean's surface waters has been about 0.1 PH decrease since the start of industrial revolution.

Well, we really don't know. Are you claiming we tested as much of the waters in the 1700's with any accuracy as we do today?

One thing to note is the estimated 0.1 is within the error margins of today even. I will assume it could be a correct number however within maybe +/- 0.02. I have no reason to believe otherwise.

Lynx_Fox wrote:

The only studies I've seen suggesting a 0.6 PH decrease are worst case ones that projections over the next few centuries and assume we're stupid enough to burn and release the entire load of fossil carbon.

I have seen links in the past claiming that change in some areas, blaming CO2. There is no way CO2 is causing that much change.

Lynx_Fox wrote:

There is considerable concern and uncertainty as to the effects of lowering PH by another 0.1 or 0.2 that looks quite likely in our lifetimes.

Yes, but is it man made or natural? The ocean currents are refreshing the lower carbinated waters. We really cannot make these surface claims for continued increase until after the ocean completely cycles. As it stands, to lower it another 0.1 would require another 30% increase in CO2. Another 30% yet for the 0.2 PH decrease. Assuming 389 ppm now, the 0.2 pH decrease would require about a 657 ppm level at 1:1. That's under static conditions. Since the ocean is flowing and dynamic, it would take a really long time to achieve that level in the atmosphere.

I disagree with that much change in our lifetime. Assuming 10 GtC added annually and 45% being absorbed, and about a 2:1 GtC to ppm, about 5.5 ppm is added annually. It would take 49 years to get to the 0.2 pH decrease if we had static numbers. Being dynamic, it would take much longer than that as we sea water less dilute in carbonic acid continually becoming surface water. We should be seeing something like 98% of the added CO2 being absorbed by the ocean rather than 45% If the ocean currents were faster, we would see a larger rate.

Simply too many factors to say with certainty. Regardless, CO2 is not the only acid compounds in the ocean, and we cannot control nature.
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mpaulj781

Posted: Tue May 25, 2010 3:01 pm Post subject: CO2 levels

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Joined: 17 Feb 2010
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I read some time ago that CO2 levels in the Cretaceous period were 10 to 20 times higher than today`s level of 0.0361% of the atmosphere.
If that is so, what on earth is all the fuss about today? After all, that level did not lead to irreversible climate change, so why should today`s level be of any concern?

I have also read on the Internet and elsewhere that the man-made CO2 is only 5% of the whole, the rest coming from decaying vegetation, volcanic activity, oceanic release and other natural sources, so to me the reduction of 20% proposed at Kyoto means 20% of 5% of 0.0361% of CO2 in the atmosphere, a totally insignificant amount. What is the point of such a reduction, apart from crippling developing countries industries?

Regards,
Mike.

LunchBox

Posted: Tue May 25, 2010 7:13 pm Post subject: Re: CO2 levels

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Joined: 14 Mar 2009
Posts: 130
Location: Texas

mpaulj781 wrote:

Because common sense "ain't so common" anymore...what you, and other "skeptics" (like me) are saying is we'd prefer to shop around a bit, instead of buying what we've been sold.
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Bunbury

Posted: Tue May 25, 2010 8:28 pm Post subject: Re: CO2 levels

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Joined: 26 Sep 2007
Posts: 1909

mpaulj781 wrote:

I have also read on the Internet and elsewhere that the man-made CO2 is only 5% of the whole, the rest coming from decaying vegetation, volcanic activity, oceanic release and other natural sources

True, except that volcanic activity is a trivial contributor compared to the anthropogenic contribution, but taking everything together 5% is about right. The problem is that the natural emissions and absorptions were in balance until humans began burning fossil fuels in large quantities. The balance has been upset and the concentration of CO2 instead of remaining roughly constant is steadily increasing.

Quote:

so to me the reduction of 20% proposed at Kyoto means 20% of 5% of 0.0361% of CO2 in the atmosphere, a totally insignificant amount.

You're right - it's not nearly enough.

Quote:

What is the point of such a reduction, apart from crippling developing countries industries?

Reducing emissions is an attempt to make the environmental changes somewhat less drastic, so that populations might have some chance to adapt to new conditions rather than be overwhelmed by them. No country's industry will be crippled. China has the third largest solar PV industry. India is manufacturing solar PV and wind turbines. North African countries can become exporters of power to Europe. You are being suckered by fossil fuel vested interests.

iceaura

Posted: Tue May 25, 2010 10:05 pm Post subject:

Forum Bachelors Degree

Joined: 05 Oct 2008
Posts: 459

mpaul wrote:

I have also read on the Internet and elsewhere that the man-made CO2 is only 5% of the whole, the rest coming from decaying vegetation, volcanic activity, oceanic release and other natural sources,

All those "sources" except volcanic, which is comparatively small, are simply releasing CO2 they had recently absorbed from the air - there's no net gain or loss to the atmosphere.

The human fossil fuel combustion is releasing carbon that was removed from the air many millions of years ago, and it adds to the total in the air present now.

Over a time scale of hundreds of millions of years, maybe no net change. But in the near future, a large accumulation of CO2 in the air.

About 40% boost so far, probably a doubling to come without curbing the anthro conribution. That will probably have some serious effects, on everything from water and soil chemsitry to temperature regimes.

jrmonroe

Posted: Wed May 26, 2010 6:59 am Post subject:

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Joined: 19 Mar 2010
Posts: 189

iceaura wrote:

The human fossil fuel combustion is releasing carbon that was removed from the air many millions of years ago, and it adds to the total in the air present now.

I wonder if experts have considered that, in addition to humans adding carbon to the air, we have also denied vegetation from re-absorbing carbon from the air? That is, have these experts also subtracted the surface area that humans alter for their uses, and thus, not allow vegetation to grow there? Vegetation grows by absorbing carbon from the air.

There's the reservoirs and artificial lakes created by building dams. The USGS says that 250,000 square miles of the earth's surface is covered in reservoirs, almost equivalent to the size of Texas.

Add to that the more than 50,000 square miles of lawns in America alone, equivalent to the size of Louisiana, which contains mostly grass allowed to grow only a couple inches high -- a grossly inefficient use of those surfaces (but "pleasing" to the human eye).

One estimate puts the area in America covered by impervious surfaces (roads, parking lots, driveways, sidewalks, etc) at 25,000 square miles, the size of West Virginia. This does not include our homes, yards, patios, garages, tool sheds, etc.

There's also the vast amounts of barren soil on farm lands between plants and rows that remain fallow -- that is, kept "weed-free" as a matter of agricultural efficiency.

I think that human effect on carbon in the air cannot be totally blamed on the release of carbon by "industrialization" (ie, chimneys and tailpipes), but also on the creation of roads, lawns, buildings, farmlands, and reservoirs that denies nature from reabsorbing the carbon. We are literally "overrunning" the planet.
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Bunbury

Posted: Wed May 26, 2010 8:33 pm Post subject:

Forum Professor

Joined: 26 Sep 2007
Posts: 1909

jrmonroe wrote:

Yes, they've considered this. The net effect of land use change appears to be a cooling one, since cropland and grassland is more reflective than forest. It's not a simple subtraction. There is the effect of lost CO2 absorption by photosynthesis, offset by increased albedo. Reforestation or afforestation in higher latitudes might actually make global warming worse.

jrmonroe

Posted: Thu May 27, 2010 5:37 am Post subject:

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Joined: 19 Mar 2010
Posts: 189

So, instead of the solar energy causing vegetation to absorb carbon, you seem to say that it mostly radiates into space instead of heating the earth's surface? Because we've all experienced brutally hot pavement, dirt roads, parking lots and sidewalks (and even unattended cars and sandy beaches), and civil engineers know that insolation (the sun's thermal energies that comes through windows) must be reckoned with in designing homes and buildings. When the sun's rays evaporate water from these impervious surfaces and all those reservoirs, that energy continues to remain trapped within the atmosphere.

The CIA World Factbook estimates that humans have made 69 million kilometers of what could be called a "road", which I estimate (if all were 20 feet wide) to be at least the area covered by California. This does not include the world's railways.

Also, add to my previous data on "impervious" (ie, "paved") surfaces all the world's dirt roads, cow paths, footpaths and other defoliated surfaces (backyard pools, worn spots under kids' swing sets, playgrounds, etc).

We're talking about reservoirs that would completely cover Texas and roadways that would completely cover California. I question that most of the sun's energy that falls on non-vegetation bounces back into space. I know what you've stated, but I have serious doubts.
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Bunbury

Posted: Thu May 27, 2010 6:16 am Post subject:

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Joined: 26 Sep 2007
Posts: 1909

jrmonroe wrote:

So, instead of the solar energy causing vegetation to absorb carbon, you seem to say that it mostly radiates into space instead of heating the earth's surface?

Huh? Of course vegetation absorbs carbon, by photosynthesis. What I just wrote if you bothered to read it was that removal of trees and replacing them with agriculture or pasture has a net cooling effect, or so the current state of research seems to show. This is because trees are dark and do not reflect sunlight very efficiently. Trees cover up snow covered ground in higher latitudes in winter so the reflectivity of snow is diminished. Cropland and pasture reflects more sunlight, and snow cover in winter adds to the reflectivity. So growing trees in the northern latitudes may not do much, if anything, to reduce global warming, and may make it worse. I would not say this proven science; it is what current research seems to indicate.

Quote:

The CIA World Factbook estimates that humans have made 69 million kilometers of what could be called a "road", which I estimate (if all were 20 feet wide) to be at least the area covered by California. This does not include the world's railways.

Also, add to my previous data on "impervious" (ie, "paved") surfaces all the world's dirt roads, cow paths, footpaths and other defoliated surfaces (backyard pools, worn spots under kids' swing sets, playgrounds, etc).

We're talking about reservoirs that would completely cover Texas and roadways that would completely cover California. I question that most of the sun's energy that falls on non-vegetation bounces back into space. I know what you've stated, but I have serious doubts.

Apparently you don't know what I stated. I didn't mention roads. There was a discussion here some time ago about painting house roofs white and using light colored construction materials for roads, e.g. concrete instead of asphalt. It's a reasonable idea, but obviously not clear cut. Concrte production, for example, is amjor source of CO2 emissions. I do not think, from what I've read previously, that the rate of new road construction is having a significant effect on climate change, but feel free to provide some info on this. Existing roads and structures do not contribute to land use change.

There was also a discussion some time ago about Ruddiman's theory that early agriculture may have prevented a cooling phase several thousand years ago. This is controversial, but has been widely discussed among the climate science community.

Climate scientists, if you bother to read some of their work, are generally aware of the things that affect, um, climate, even if they don't fully understand what the effects are.

jrmonroe

Posted: Fri May 28, 2010 8:29 am Post subject:

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Joined: 19 Mar 2010
Posts: 189

Thank you Bunbury. I did read what you wrote and I 'm not exactly disagreeing with you, but I wasn't sure if what you stated took into account the opposite affects or other effects. I'm trying to see the whole picture.

I look at situations such as GW in terms of "Systems Thinking", where a "cause" can create a positive and negative (as well as immediate and delayed) influences -- some of them circuitous -- on the "effect". So, to my eyes, all these considerations are a matter of the magnitude and polarity of coefficients in matrices. That is, the "weight" of a particular influence produced by a "cause" upon an "effect". So, according to this paper (near the bottom of page 1), I am trying to make reliable inferences about behavior by developing an increasingly deep understanding of underlying structures.

For example, man-made impervious ground surfaces (asphalt, concrete, etc) create: reflection of sunlight (a negative effect on GW), conversion of sunlight to thermal energy (a positive effect on GW), and inhibition of vegetation (a positive effect on GW by not allowing vegetation to absorb carbon dioxide from the air, which in turn, increases GW). And, rhetorically, do the positives outweigh the negatives, or vice versa?

My first post here wondered if experts had taken into account all the possible causes and their influences (some of them circuitous) on GW -- that is, civilization encroaches on the environment in many ways, and have the experts looked deep enough, or did they stop looking after finding what they think are the major pathways?

Let me say that, offhand (ie, admittedly without reading the plethora of research papers on GW), I would consider "dark trees absorbing energy" to indicate also that they use that energy through photosynthesis to absorb carbon dioxide, which in turn, reduces GW. It also seems that capillary action in trees results from being alive (ie, photosynthesis), thus trees convert solar energy into the potential energy of the water raised from the roots to the leaves plus the energy of evaporation of that water from the leaves.
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Bunbury

Posted: Fri May 28, 2010 11:13 am Post subject:

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Joined: 26 Sep 2007
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As you say it is very complex and there are feedbacks in addition to the direct effects, some of which you describe. If you don’t account for feedbacks your inferences will be meaningless. I would suggest that reliable inferences are in fact pretty much impossible without actually making mathematical models. Inferences without calculation are going to be fairly misleading.

There are at least thirteen (IIRC) accredited models in use that have been applied and tested for years against historical data and against each other and have made good predictions. The major weakness in all models is (to the best of my knowledge) the modeling of clouds, but as in the case of urbanization, clouds are not ignored – they are modeled making assumptions which will improve over time. Forgive my skepticism that your inferences will show us anything significant.

Regarding trees, here’s an article:

Quote:

A 150-year simulation of worldwide deforestation finds that tropical forests are carbon sinks and boreal forests contribute to warming

http://www.scientificamerican.com/article.cfm?id=tropical-forests-cool-earth

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