Global Warming/Climate Change: Is it only a concern in caused by humans?

[Mr. Pedantic]

A co-worker and I started talking about it, and I, playing devils advocate, blamed it all on humans and that it would ultimately lead to our demise. But I really didn't have any real scientific facts to back it up. I heard the hole is the ozone is getting smaller, but then I heard that the north pole is becoming a lake. I am just wondering, what everyones opinion is? Is climate change something to worry about or is it a natural cycle? No doubt pollution is bad and we are causing great harm to the earth, but are we causing the climate change? How do you prove something like that?

The logical fallacy here is that it's only worth doing something about if it's anthropogenic. The world turning into a greenhouse would be completely disastrous for human civilisation, even if it were part of the Earth's "natural cycle".

 

[Brainonska511]

If you are incapable of publishing then you are VERY bad at being a scientist. If he's got 10k citations from the 1980s then maybe he was cutting edge 3 decades ago: but if he can't still publish then he doesn't know his shit today.

Yes, but he could be publishing bullshit today and his CV would appear to have a lot of publications. Being in science, I know exactly how a CV works. My point is, it doesn't tell you about the quality of someone's work.

 

[Dr. Zaus]

Yes, but he could be publishing bullshit today and his CV would appear to have a lot of publications. Being in science, I know exactly how a CV works. My point is, it doesn't tell you about the quality of someone's work.

Yep, lets look at google scholar:

http://scholar.google.com/citations...=ZEN_Z2UAAAAJ&pagesize=100&view_op=list_works

Here's one of the recent papers:
http://www.ourenergypolicy.org/wp-content/uploads/2013/05/1748-9326_8_2_024024.pdf

and here's the findings of an analysis abstracts across just under 12,000 articles:

We find that 66.4% of abstracts expressed no position on AGW, 32.6% endorsed AGW, 0.7% rejected AGW and 0.3% were uncertain about the cause of global warming.Among abstracts expressing a position on AGW, 97.1% endorsed the consensus position that humans are causing global warming.

 

[monovillage]

Credibility doesn't matter. Cook is summarizing the climate science literature, and backs up every claim with a link to the primary source. The climate science literature is what matters, not who's assembling it for a lay audience. But nice try with the appeals to authority.

So you can't do it or you won't do it. I thought so. Thank you.

 

[Jaskalas]

Yep, lets look at google scholar:

http://scholar.google.com/citations...=ZEN_Z2UAAAAJ&pagesize=100&view_op=list_works

Here's one of the recent papers:
http://www.ourenergypolicy.org/wp-content/uploads/2013/05/1748-9326_8_2_024024.pdf

and here's the findings of an analysis abstracts across just under 12,000 articles:

We find that 66.4% of abstracts expressed no position on AGW, 32.6% endorsed AGW, 0.7% rejected AGW and 0.3% were uncertain about the cause of global warming.Among abstracts expressing a position on AGW, 97.1% endorsed the consensus position that humans are causing global warming.

You just lied.

Please clarify though, just to be sure. You think that 97.1% entails a belief that human emissions are predominantly responsible for the observed warming of the 20th century? That's not what the Cook survey says. My link explains in detail.

I am among that 97.1%. Please let that sink in for a moment. In fact, I'm a category above the minimum in "support", which is really nothing more than I believe human emissions will warm the planet. The great question is "how much"? Only the top category proclaims we dominate changes to the observed temperature. 65 papers out of 12,000 supported that notion. That's not 97%.

But let's be clear, I believe "humans cause global warming" if you want to be technical about it. So maybe that's all you meant. But if we warm it less than 1C per doubling of CO2 then there's nothing to concern ourselves with.

This so called "consensus" does not speak to Climate Sensitivity.

 

[GreenMeters]

So you can't do it or you won't do it. I thought so. Thank you.

I won't do it, because it was a dishonest question. The argument from authority fallacy doesn't fly here.

 

[GreenMeters]

This so called "consensus" does not speak to Climate Sensitivity.

Utter nonsense. By your poor logic and that of your link, a hypothetical paper that demonstrated an very high sensitivity, say an increase of 10 degrees C for a doubling of CO2, wouldn't count towards the "climate change is dominated by anthropogenic effects" unless the paper explicitly said "and therefore humans are causing global warming".

Completely ridiculous and disingenuous. Papers have page limits, so there's no reason to belabor the obvious. We have consensus around the fact that climate sensitivity is around 3 degree C for a doubling of CO2, and consensus around the fact that human activity is responsible for the measured increase in atmospheric CO2, and consensus around the fact that the expected temperature increase due to the measured CO2 increase perfectly correlates with the measured temperature increase. Thus the body of work at large demonstrates the consensus that global warming is driven by human activity, as Cook demonstrated. Note also how well his results from the survey of climate science literature correlates with opinion surveys of climate scientists.

So someone is lying, but it sure isn't DixyCrat...

 

[monovillage]

There is no consensus on consensus. We can also see how a preeminent climate scientist disagrees with the position of Greenmetre on the false 97% number.

http://judithcurry.com/2013/07/26/the-97-consensus/

I’m sure most of you have encountered the recent paper by Cook et al. (2013) Quantifying the consensus on anthropogenic global warming in the scientific literature, which includes John Cook and Dana Nuccitelli of SkepticalScience fame. And the many critiques of this study that have appeared at WUWT, Blackboard, etc.

IMO, the main point of all this is that he concept of a ‘consensus’ surrounding climate change is becoming increasingly meaningless.

Ben Pile’s recent post What’s behind the battle of received wisdoms? has certainly stirred the pot. Some excerpts from Pile’s post:

On the pages of the Guardian’s environment blog, Dana Nuccitelli (who is not a climate scientist) compiled a list of what he thought were Neil’s mistakes. ‘These are your climate errors on BBC Sunday Politics‘, he proclaimed. But half of Nuccitelli’s rebuttals related to Neil’s treatment of the study into the extent of the scientific consensus on climate change, co-authored by Nuccitelli, which represents (according to the study) the views of 97% of scientists. Davey had cited the study during the interview, but Neil had said that it had been largely discredited.

http://judithcurry.com/2013/07/27/the-97-consensus-part-ii/

[T]here’s good reason to believe that the self-righteous and contemptuous tone with which the “scientific consensus” point is typically advanced (“assault on reason,” “the debate is over” etc.) deepens polarization. That’s because “scientific consensus,” when used as a rhetorical bludgeon, predictably excites reciprocally contemptuous and recriminatory responses by those who are being beaten about the head and neck with it. – Dan Kahan

 

[Jaskalas]

Utter nonsense. By your poor logic and that of your link, a hypothetical paper that demonstrated an very high sensitivity, say an increase of 10 degrees C for a doubling of CO2, wouldn't count towards the "climate change is dominated by anthropogenic effects" unless the paper explicitly said "and therefore humans are causing global warming".

Take it up with John Cook, its his survey. Of which I am Category 2:

Category 1: 65

1. Explicit Endorsement of AGW with quantification
1.1 Mention that human activity is a dominant influence or has caused most of recent climate change (>50%).
1.2 Endorsing the IPCC without explicitly quantifying doesnt count as explicit endorsement – that would be implicit.

Category 2: 934 (me)

2. Explicit Endorsement of AGW without quantification
2.1 Mention of anthropogenic global warming or anthropogenic climate change as a given fact.
2.2 Mention of increased CO2 leading to higher temperatures without including anthropogenic or reference to human influence/activity relegates to implicit endorsement.

Category 3: 2,933

3. Implicit Endorsement of AGW
3.1 Mitigation papers that examine GHG emission reduction or carbon sequestration, linking it to climate change
3.2 Climate modelling papers that talks about emission scenarios and subsequent warming or other climate impacts from increased CO2 in the abstract implicitly endorse that GHGs cause warming
3.3 Paleoclimate papers that link CO2 to climate change
3.4 Papers about climate policy (specifically mitigation of GHG emissions) unless they restrict their focus to non-GHG issues like CFC emissions in which case neutral
3.5 Modelling of increased CO2 effect on regional temperature – not explicitly saying global warming but implying warming from CO2
3.6 Endorsement of IPCC findings is usually an implicit endorsement. (updated this so it is more than just reference to IPCC but actual endorsement of IPCC)

We have consensus around the fact that climate sensitivity is around 3 degree C for a doubling of CO2, and consensus around the fact that human activity is responsible for the measured increase in atmospheric CO2, and consensus around the fact that the expected temperature increase due to the measured CO2 increase perfectly correlates with the measured temperature increase. Thus the body of work at large demonstrates the consensus that global warming is driven by human activity, as Cook demonstrated. Note also how well his results from the survey of climate science literature correlates with opinion surveys of climate scientists.

Maybe there should be a survey regarding the issue at hand, Climate Sensitivity, instead of the more obvious "attempt to deny the physical properties of CO2". I'm sure there are plenty of "deniers" who would, people are either ignorant or whipped up into a backlash to hate on the concept, but we all dismiss them anyway.

Category 1 speaks to the IPCC claim.

Now specifically look at 1.1. This comes close to the iconic statement from the IPCC AR4 report which said that “Most of the observed increase in global average temperatures since the mid-20th century is very likely due to the observed increase in anthropogenic greenhouse gas concentrations.”

IMO, you will find your strongest opposition to Category 1 in Category 2. You're right, there may be a mix of supporters and opponents of the IPCC statement in Category 2 - but there is no quantification of them.

As for your new claim of a consensus of 3C Climate Sensitivity, IMO that's not true at all. The IPCC gives a range and calls it an estimate. 2-4C they make claims on. Some outliers even say 6C. NASA says we'll rise 8F warmer in the next 87 years. These must be disputed, especially since there has been no warming for 17 years. Especially since the climate models on which they are based have failed to accurately predict temperature.

Now, if we somehow rise another 0.5C by 2020 then you may to onto something. The notion of debating Climate Sensitivity would come to a close as surely the ocean cycles have played their part by then and we have no further natural forcing to explain. By then simplicity would yield you the proper ground.

If we are significantly warmer in 2020, to indicate more than 1C per doubling, and no new convincing arguments remain on my own "side", then I would join you.

 

[GreenMeters]

Take it up with John Cook, its his survey.

No, I'm taking it up with you, because your interpretation of Cook's rating system (or rather, the interpretation you're aping from Judith Curry) is ludicrous and disingenuous.

As for your new claim of a consensus of 3C Climate Sensitivity, IMO that's not true at all.

I'd call your opinion uninformed, expect you then regurgitate various sources that all actually support the fact that 3C for a doubling of CO2 is the consensus. 2-4C from IPCC (itself a summary of climate science consensus). Hmm, what's the midpoint of that range? NASA's estimates align with that range (surely you're not slipping in measurements in F just to make things look askew, right?) for their stated assumptions about greenhouse gas emission trends. Since that rules out ignorance, I'll go back to my statement that it's clear DixyCrat is not the liar here.

 

[Dr. Zaus]

[/B][/U]

You just lied.

Please clarify though, just to be sure. You think that 97.1% entails a belief that human emissions are predominantly responsible for the observed warming of the 20th century?

I posted an peer reviewed scientific article from last year. If it's wrong then take it up with him, I just reported it.

And the abstract doesn't say human emissions are predominantly responsible. It says humans are causing global warming. That does not go to the % of the effect, just that they are part of the effect.

 

[JTsyo]

Yes nature does output a lot more CO2 that what humans have done, but nature also absorbs CO2 so overall CO2 rate remains rather steady from nature.( unless there is an event that isn't normal.) While humans have a large net increase to CO2 output. Plus the increase in CO2 is measured in the atmosphere and in other places.

Not to mention cutting down a fair amount of trees each year.

 

[piasabird]

Volcanoes produce a lot of the same gases. Same thing goes for Forest Fires.

I dont look so much at whether there is globalwarming. Instead I like to look at what we can do about it. I think the world needs to convice and pressure countries like China that just dont care about pollution. China could significantly reduce the amount of carbon they produce. It is like they want to punish their own people. In the USA we have been significanly reducing the amount of carbon we output from factories and the EPA is tring to get coal fired power plants to clean up their act also.

So what is next?
Plant trees every year - They use school children to do this in South Korea.
Outlaw Charcoal Grills?
Outlaw burining brush?
Outlaw Firewood?
Tax Cars and Trucks based on Vehicle Weight and milage.
Give Tax rebates to people who live in smaller houses.

That is funny. Fire Swamps. Remind you of a movie?

Use methane from landfills to make electricity.

Make builders and developers build apartments instead of Houses with cement and metal instead of Wood Frame Construction.

 

[Agent11]

When you talk trees it gets complicated.

For example in northern California so much water is being diverted for southern California that the lake I learned to swim in doesn't exist anymore and the Eel river is very low. This greatly impacts the Redwood forrest, and increases the chances of disease and wild fires.

Doesn't matter how many you plant, you can not replace a forrest of 300+ foot trees that way.

 

[Paratus]

When the day comes that they actually have accurate models, then I will more readily accept the Climate Sensitivity they used for them.

Instead of making this black and white you might consider the words of Isaac Asimov:

The Skeptical Inquirer, Fall 1989, Vol. 14, No. 1, Pp. 35-44

The Relativity of Wrong
By Isaac Asimov

I RECEIVED a letter the other day. It was handwritten in crabbed penmanship so that it was very difficult to read. Nevertheless, I tried to make it out just in case it might prove to be important. In the first sentence, the writer told me he was majoring in English literature, but felt he needed to teach me science. (I sighed a bit, for I knew very few English Lit majors who are equipped to teach me science, but I am very aware of the vast state of my ignorance and I am prepared to learn as much as I can from anyone, so I read on.)

It seemed that in one of my innumerable essays, I had expressed a certain gladness at living in a century in which we finally got the basis of the universe straight.

I didn't go into detail in the matter, but what I meant was that we now know the basic rules governing the universe, together with the gravitational interrelationships of its gross components, as shown in the theory of relativity worked out between 1905 and 1916. We also know the basic rules governing the subatomic particles and their interrelationships, since these are very neatly described by the quantum theory worked out between 1900 and 1930. What's more, we have found that the galaxies and clusters of galaxies are the basic units of the physical universe, as discovered between 1920 and 1930.

These are all twentieth-century discoveries, you see.

The young specialist in English Lit, having quoted me, went on to lecture me severely on the fact that in every century people have thought they understood the universe at last, and in every century they were proved to be wrong. It follows that the one thing we can say about our modern "knowledge" is that it is wrong. The young man then quoted with approval what Socrates had said on learning that the Delphic oracle had proclaimed him the wisest man in Greece. "If I am the wisest man," said Socrates, "it is because I alone know that I know nothing." the implication was that I was very foolish because I was under the impression I knew a great deal.

My answer to him was, "John, when people thought the earth was flat, they were wrong. When people thought the earth was spherical, they were wrong. But if you think that thinking the earth is spherical is just as wrong as thinking the earth is flat, then your view is wronger than both of them put together."

The basic trouble, you see, is that people think that "right" and "wrong" are absolute; that everything that isn't perfectly and completely right is totally and equally wrong.

However, I don't think that's so. It seems to me that right and wrong are fuzzy concepts, and I will devote this essay to an explanation of why I think so.

When my friend the English literature expert tells me that in every century scientists think they have worked out the universe and are always wrong, what I want to know is how wrong are they? Are they always wrong to the same degree? Let's take an example.

In the early days of civilization, the general feeling was that the earth was flat. This was not because people were stupid, or because they were intent on believing silly things. They felt it was flat on the basis of sound evidence. It was not just a matter of "That's how it looks," because the earth does not look flat. It looks chaotically bumpy, with hills, valleys, ravines, cliffs, and so on.

Of course there are plains where, over limited areas, the earth's surface does look fairly flat. One of those plains is in the Tigris-Euphrates area, where the first historical civilization (one with writing) developed, that of the Sumerians.

Perhaps it was the appearance of the plain that persuaded the clever Sumerians to accept the generalization that the earth was flat; that if you somehow evened out all the elevations and depressions, you would be left with flatness. Contributing to the notion may have been the fact that stretches of water (ponds and lakes) looked pretty flat on quiet days.

Another way of looking at it is to ask what is the "curvature" of the earth's surface Over a considerable length, how much does the surface deviate (on the average) from perfect flatness. The flat-earth theory would make it seem that the surface doesn't deviate from flatness at all, that its curvature is 0 to the mile.

Nowadays, of course, we are taught that the flat-earth theory is wrong; that it is all wrong, terribly wrong, absolutely. But it isn't. The curvature of the earth is nearly 0 per mile, so that although the flat-earth theory is wrong, it happens to be nearly right. That's why the theory lasted so long.

There were reasons, to be sure, to find the flat-earth theory unsatisfactory and, about 350 B.C., the Greek philosopher Aristotle summarized them. First, certain stars disappeared beyond the Southern Hemisphere as one traveled north, and beyond the Northern Hemisphere as one traveled south. Second, the earth's shadow on the moon during a lunar eclipse was always the arc of a circle. Third, here on the earth itself, ships disappeared beyond the horizon hull-first in whatever direction they were traveling.

All three observations could not be reasonably explained if the earth's surface were flat, but could be explained by assuming the earth to be a sphere.

What's more, Aristotle believed that all solid matter tended to move toward a common center, and if solid matter did this, it would end up as a sphere. A given volume of matter is, on the average, closer to a common center if it is a sphere than if it is any other shape whatever.

About a century after Aristotle, the Greek philosopher Eratosthenes noted that the sun cast a shadow of different lengths at different latitudes (all the shadows would be the same length if the earth's surface were flat). From the difference in shadow length, he calculated the size of the earthly sphere and it turned out to be 25,000 miles in circumference.

The curvature of such a sphere is about 0.000126 per mile, a quantity very close to 0 per mile, as you can see, and one not easily measured by the techniques at the disposal of the ancients. The tiny difference between 0 and 0.000126 accounts for the fact that it took so long to pass from the flat earth to the spherical earth.

Mind you, even a tiny difference, such as that between 0 and 0.000126, can be extremely important. That difference mounts up. The earth cannot be mapped over large areas with any accuracy at all if the difference isn't taken into account and if the earth isn't considered a sphere rather than a flat surface. Long ocean voyages can't be undertaken with any reasonable way of locating one's own position in the ocean unless the earth is considered spherical rather than flat.

Furthermore, the flat earth presupposes the possibility of an infinite earth, or of the existence of an "end" to the surface. The spherical earth, however, postulates an earth that is both endless and yet finite, and it is the latter postulate that is consistent with all later findings.

So, although the flat-earth theory is only slightly wrong and is a credit to its inventors, all things considered, it is wrong enough to be discarded in favor of the spherical-earth theory.

And yet is the earth a sphere?

No, it is not a sphere; not in the strict mathematical sense. A sphere has certain mathematical properties - for instance, all diameters (that is, all straight lines that pass from one point on its surface, through the center, to another point on its surface) have the same length.

That, however, is not true of the earth. Various diameters of the earth differ in length.

What gave people the notion the earth wasn't a true sphere? To begin with, the sun and the moon have outlines that are perfect circles within the limits of measurement in the early days of the telescope. This is consistent with the supposition that the sun and the moon are perfectly spherical in shape.

However, when Jupiter and Saturn were observed by the first telescopic observers, it became quickly apparent that the outlines of those planets were not circles, but distinct ellipses. That meant that Jupiter and Saturn were not true spheres.

Isaac Newton, toward the end of the seventeenth century, showed that a massive body would form a sphere under the pull of gravitational forces (exactly as Aristotle had argued), but only if it were not rotating. If it were rotating, a centrifugal effect would be set up that would lift the body's substance against gravity, and this effect would be greater the closer to the equator you progressed. The effect would also be greater the more rapidly a spherical object rotated, and Jupiter and Saturn rotated very rapidly indeed.

The earth rotated much more slowly than Jupiter or Saturn so the effect should be smaller, but it should still be there. Actual measurements of the curvature of the earth were carried out in the eighteenth century and Newton was proved correct.

The earth has an equatorial bulge, in other words. It is flattened at the poles. It is an "oblate spheroid" rather than a sphere. This means that the various diameters of the earth differ in length. The longest diameters are any of those that stretch from one point on the equator to an opposite point on the equator. This "equatorial diameter" is 12,755 kilometers (7,927 miles). The shortest diameter is from the North Pole to the South Pole and this "polar diameter" is 12,711 kilometers (7,900 miles).

The difference between the longest and shortest diameters is 44 kilometers (27 miles), and that means that the "oblateness" of the earth (its departure from true sphericity) is 44/12755, or 0.0034. This amounts to l/3 of 1 percent.

To put it another way, on a flat surface, curvature is 0 per mile everywhere. On the earth's spherical surface, curvature is 0.000126 per mile everywhere (or 8 inches per mile). On the earth's oblate spheroidal surface, the curvature varies from 7.973 inches to the mile to 8.027 inches to the mile.

The correction in going from spherical to oblate spheroidal is much smaller than going from flat to spherical. Therefore, although the notion of the earth as a sphere is wrong, strictly speaking, it is not as wrong as the notion of the earth as flat.

Even the oblate-spheroidal notion of the earth is wrong, strictly speaking. In 1958, when the satellite Vanguard I was put into orbit about the earth, it was able to measure the local gravitational pull of the earth--and therefore its shape--with unprecedented precision. It turned out that the equatorial bulge south of the equator was slightly bulgier than the bulge north of the equator, and that the South Pole sea level was slightly nearer the center of the earth than the North Pole sea level was.

There seemed no other way of describing this than by saying the earth was pear-shaped, and at once many people decided that the earth was nothing like a sphere but was shaped like a Bartlett pear dangling in space. Actually, the pear-like deviation from oblate-spheroid perfect was a matter of yards rather than miles, and the adjustment of curvature was in the millionths of an inch per mile.

In short, my English Lit friend, living in a mental world of absolute rights and wrongs, may be imagining that because all theories are wrong, the earth may be thought spherical now, but cubical next century, and a hollow icosahedron the next, and a doughnut shape the one after.

What actually happens is that once scientists get hold of a good concept they gradually refine and extend it with greater and greater subtlety as their instruments of measurement improve. Theories are not so much wrong as incomplete.

This can be pointed out in many cases other than just the shape of the earth. Even when a new theory seems to represent a revolution, it usually arises out of small refinements. If something more than a small refinement were needed, then the old theory would never have endured.

Copernicus switched from an earth-centered planetary system to a sun-centered one. In doing so, he switched from something that was obvious to something that was apparently ridiculous. However, it was a matter of finding better ways of calculating the motion of the planets in the sky, and eventually the geocentric theory was just left behind. It was precisely because the old theory gave results that were fairly good by the measurement standards of the time that kept it in being so long.

Again, it is because the geological formations of the earth change so slowly and the living things upon it evolve so slowly that it seemed reasonable at first to suppose that there was no change and that the earth and life always existed as they do today. If that were so, it would make no difference whether the earth and life were billions of years old or thousands. Thousands were easier to grasp.

But when careful observation showed that the earth and life were changing at a rate that was very tiny but not zero, then it became clear that the earth and life had to be very old. Modern geology came into being, and so did the notion of biological evolution.

If the rate of change were more rapid, geology and evolution would have reached their modern state in ancient times. It is only because the difference between the rate of change in a static universe and the rate of change in an evolutionary one is that between zero and very nearly zero that the creationists can continue propagating their folly.

Since the refinements in theory grow smaller and smaller, even quite ancient theories must have been sufficiently right to allow advances to be made; advances that were not wiped out by subsequent refinements.

The Greeks introduced the notion of latitude and longitude, for instance, and made reasonable maps of the Mediterranean basin even without taking sphericity into account, and we still use latitude and longitude today.

The Sumerians were probably the first to establish the principle that planetary movements in the sky exhibit regularity and can be predicted, and they proceeded to work out ways of doing so even though they assumed the earth to be the center of the universe. Their measurements have been enormously refined but the principle remains.

Naturally, the theories we now have might be considered wrong in the simplistic sense of my English Lit correspondent, but in a much truer and subtler sense, they need only be considered incomplete.

 

[mikeymikec]

I don't know whether I should resurrect this thread or start a new one, but I came across some (IMO) pretty unstoppable logic on the topic of global warming:

http://www.youtube.com/watch?v=zORv8wwiadQ

The video title is silly, I found it embedded on another site.

 

[haleyjohnas]

That's the attitude! Bravo!

 

[Paratus]

That's the attitude! Bravo!

Interesting necro. What were you searching for?