Sorry Sagan…

The Sun - Image from NASA
There are many, many data sets that clearly indicate the earth is young. I have blogged about several of them, some of which give direct measurements indicating that the earth is about 10,000 years old. Other data sets simply put upper limits on the age of the earth. One of those data sets is based on the behavior of the sun. As I have blogged before, the sun produces energy via thermonuclear fusion, and we know enough about thermonuclear fusion to understand that if the sun really has been around for billions of years, it is significantly hotter now than it was back then, probably by about 25%.

This, of course, produces a problem for an earth that is supposedly billions of years old. After all, the earth needs a certain amount of energy in order to support life. A billions-of-years-old sun would produce significantly less energy in the distant past than it does now, resulting in an earth that is simply too cold to support life.

Of course there are many scientists who are so desperate to believe in a billions-of-years-old earth that they are forced to produce some sort of narrative so that they can “explain around” this obvious problem. Once such scientist was Carl Sagan. In 1972, he and a colleague wrote a paper1 that suggested that the problem could be solved if the concentration of carbon dioxide in the atmosphere was significantly greater in the distant past.** He fervently hoped that a lot of extra carbon dioxide would produce a much stronger greenhouse effect, making the earth sufficiently warm enough for life, even when the sun was a lot dimmer.

Now this is only a partial solution to the problem, because not only did Sagan need to have faith that carbon dioxide concentrations in the atmosphere were significantly greater in the past, he also had to ardently believe that those concentrations would slowly fall in perfect coordination with the increase in the brightness of the sun so that the earth would never get too hot or too cold as the sun got brighter and brighter.

Well, now we know that despite Sagan’s desperate hopes, his explanation doesn’t work.

In the April first issue of the journal Nature, Rosing and colleagues report on a study of minerals in rocks that scientifically irresponsible dating methods indicate are 3.8 billion years old. Based on how we know the minerals in these rocks form, the authors suggest that the maximum amount of carbon dioxide in the atmosphere when the rocks formed was about 1000 parts per million (a nice round number).2 This is not nearly enough to cause the necessary greenhouse effect to keep the earth warm enough under an ancient, dim sun.

So now that we know Sagan’s attempt to explain around the problem doesn’t work, what do the authors suggest? Well, even though they desperately want to believe that the earth’s temperature has remained relatively stable over the supposed billions of years during which life has supposedly been evolving, they don’t provide any solid answers. In fact, they say:

The Earth’s surface environment over the approximately 4 billion years (Gyr) recorded in geologic formations appears to have been maintained within a relatively narrow range in which liquid water was stable. This is surprising…It is not readily apparent to what extent this apparent thermostasis can be attributed to physico-chemical feedback mechanisms, metabolic interventions from living organisms, or combinations of unrelated secular changes.3

Now of course, such a situation will not do for people who are forced to ignore the data and believe in a billions-of-years-old earth, so they come up with a hypothesis:

…we hypothesize that a lower albedo on the Earth, owing to considerably less continental area and to the lack of biologically induced cloud condensation nuclei, made an important contribution to moderating surface temperature4

The albedo* of a planet is simply a measure of how reflective it is. If a planet reflects a lot of the sun’s light back into space, that light obviously can’t be used to warm the planet. Thus, Rosing and colleagues suggest that there might have been less land and fewer clouds back in the distant past, so the earth absorbed more of the sun’s light than it does now. Of course, like Sagan’s explanation, this requires a remarkably well-timed scenario in which the albedo of the earth magically increases at just the right pace as the sun brightens, so that the earth continually gets just the right amount of energy to allow for life to exist.

Boy…I am glad that I believe in looking at the data and therefore conclude that the earth is young. I just don’t have enough faith to believe nonsense like that!


1. Carl Sagan and George Mullen, “Earth and Mars: Evolution of Atmospheres and Surface Temperatures,” Science 177:52 – 56, 1972
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2. Minik T. Rosing, Dennis K. Bird, Norman H. Sleep, and Christian J. Bjerrum, “No climate paradox under the faint early Sun,” Nature 464:744-747, 2010
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3. Ibid, p. 745
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4. Ibid, p. 744
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*If you are reading this, Black Sheep, its ALBEDO, not LIBIDO
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** I got this wrong. Sagan and his colleague suggested ammonia. However, it was quickly shown that ammonia would not be stable in the atmosphere, so it could not be used as a way to sustain the needed warmth. As a result, others suggested a mix of carbon dioxide and water.
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18 thoughts on “Sorry Sagan…”

  1. HAHA! Thanks for the shout out… and clarification. I must admit, I think it’d be far more interesting if you were indeed discussing a planet’s libido (how would one go about measuring that for a planet?). Also, is the last line a quote stolen from me? Sounds like something I’d say.

    1. I would think one measure of a planet’s libido is how close its moons are…

      I wouldn’t be surprised if I stole that last line from you. It does sound like something you’de say.

  2. Once again, I can’t get access to the full paper because Nature embargoes their articles for a year on public databases. But I’ll address this claim instead:

    “I have blogged about several of them, some of which give direct measurements indicating that the earth is about 10,000 years old.”

    Why no link for this statement on direct measurements, as opposed to upper limits? It’s because you don’t have any links to provide. Instead, you say things like:

    “Well, a consequence of this incredibly successful theory is that the earth and the solar system cannot be more than 10,000 years old. That’s a result of the mathematics.” Link

    “Given the fact that tree rings indicate the oldest living tree to be about 5,000 years old (roughly when you would expect the worldwide flood to have happened), and given the fact that the oldest tree ring chronologies (which are upper limits) extend only to a bit over 10,000 years, it is hard to believe that these kinds of trees have existed for hundreds of millions of years.” Link.

    “Now don’t get me wrong. There IS evidence that the earth is billions of years old. However, the majority of it comes from processes that have not been studied long and are poorly understood. Thus, while the evidence does exist, I find it less reliable than evidence like what has been presented in this series. For now, then, I think the most reasonable scientific conclusion is that the earth is young, most likely on the order of 10,000 years old.” Link

    “However, since I am a young-earth creationist, my Biblical worldview includes the idea of a supernatural creation that occurred probably less than 10,000 years ago, a worldwide flood, etc. As a result, that’s the kind of Biblical worldview I will be discussing.” Link

    Those are all the mentions of 10,000 years from all of your blog posts. That’s it. Google search of your blog for mentions of “10,000”. Most search results are from comments.

    I don’t think the data supports your claim.

    1. So once again, Shooter, you are too lazy to go to the library and actually learn something. It’s sad, but it’s not surprising.

      You really need to look at the DATA. Of course, if you are too lazy to go to the library, it’s not surprising that you are too lazy to actually think about what you are reading and then check the references. I concentrate on upper limits, as that is the most scientific thing to do. However, if you would bother to check the references, you will find that Humphreys’s magnetic field study measures the decay time of the earth’s magnetic field (Equation 7), the magnetic moment in 1980 (equation 8), and his theory predicts the ORIGINAL magnetic moment (Equation 9). From that, Equation 5 gives a MEASURED age of the earth (in 1980) of 5,895 years. If you stretch all the errors out as much as possible so that you are at the 95% confidence limit (the most reasonable criterion), you get an upper limit of 10,000 years.

      Also, in the study on helium in zircons, they MEASURE the age of rocks that are supposed to be 1.5 billion years old as 5,681 +/- 1999 years old. Once again, focusing on the 95% confidence limit (the most reasonable criterion), you get an upper limit of 10,000 years old.

      What this shows is that you don’t bother to actually look at the data. Of course, that’s not at all surprising, as it seems to be your standard mode of operation – ignore the data and feverishly hope it will all go away.

      Also, I have told you this before, but you seem incapable of learning. The word “data” is plural. Please try to keep up!

  3. 🙂 Very cheeky, Shooter. Given that Doctor Wile is not Doctor Who, it would be rather hard to take a direct measurement as to the age of the earth.

    The problem is that scientists do use math in combination with science. First you take the measurements, say the concentration of Salt in the Ocean or the radiation emitted by the sun. Then you can use the information, through mathematics, to make predictions.

    You will notice that anybody who cites carbon dated fossils as evidence of age does exactly the same thing, albeit with measurements in a field far less understood. They measure the level of C-14, estimate the initial concentration in the lifeform. Then comes the math: divide the initial C-14 level by the modern C-14 level. Take the base 2 log of that number and multiply by the half life of carbon 14–5730 years.

    1. Adrian, that tree is not 13,000 years old, and the study did not really measure its age. Indeed, the authors admit:

      Excavations at the Jurupa site failed to produce any significant amounts of old, dead wood. This absence of old material, likely due to termite activity, made it impossible to determine the age of the putative clone directly by means of radiocarbon dating. Instead, we counted annual growth rings in multiple stem cross-sections to determine average annual growth rate.

      So they had no original wood to date. Instead, they counted rings in some recent growth, ASSUMED that the average growth rate has remained the same throughout the lifetime of the tree, and then used the SIZE to determine the age. This, of course, is an incredibly poor way to measure the age of something, as many, many factor influence growth rate, and to assume it has stayed constant over the course of the tree’s life is absurd.

  4. Please confirm: Magnetic fields give a 5000 year old earth, Helium Ziricrons gives 5000 year old rocks, and tree rings give us a 5000 year old tree and running link to a 13000 year old tree.

    That seems like a problem to me.

  5. Direct measurement meant an actual number, such as 4.54 billion years, +/- 1%, as opposed to an upper limit, such as no older than 10,000 years. Again, that’s an awfully round number to use, creation science can’t get it more precisely?

    Also, what about creationist who say the earth is no older than 6,000 years? Why are they wrong?

    Why do you keep citing the same old papers, magnetic fields and zircons?

    1. Shooter, the sources I gave you did make direct measurements that led to actual numbers. You may not want to admit that, but it is true, nevertheless. Now I personally think that when dealing with historical science, upper limits are the more scientific way to approach the age of something.

      You seem to think that measurement is something magical. It is not. You get what you get, round numbers or not. Indeed, the study I cited in this article gets a carbon dioxide level of 1000 parts per million. Are you going to assume it is wrong because it is a round number? You seem to be very ignorant of the way science works. Scientists make measurements and get answers. They don’t throw away the answers because they don’t like them – at least not when they are doing science.

      I assume the creationists who say the earth is no older than 6,000 years are concentrating only on specific data. There are some data (like the magnetic fields and zircon data) that give numbers consistent with that idea. However, when you look at all the relevant data, 10,000 years is the age that is consistent with the most data. Of course, those creationists are not the issue here. The data are the issue here, and that’s what frustrates you so much! It frustrates you so much that you must distract from the data by asking irrelevant questions.

      I don’t cite just magnetic fields and zircons when I discuss the age of the earth. Once again, just click on “age of the earth” and see the many, varied data sets I discuss, because there is an enormous amount of evidence that the earth is young. However, in this case you wanted something specific, and the data from magnetic fields and zircons provide what you wanted.

      Why do you keep ignoring magnetic fields and zircons? I actually know the answer to that one – it’s because you ignore any data that disagree with your preconceived views. That might make you sleep better at night, but it is not scientific or rational.

      Why do you keep citing the same silly age of the earth?

  6. Why do you keep referring to the same old dating method, shooter? I’ve been looking up your 4.54 billion years and it is entirely dependent upon radiodating. Now if the Helium diffusion from zircons study does indeed so completely undermine that radiodating it’s a hugely important factor that deserves to be cited every time somebody uses the 4.54 B figure.

    A 6000 year earth could be considered consistent with the DIRECT MEASUREMENTS you want from the magnetic field study and zircon study, and of course below the upper limit. Still such a strict interpretation of the genealogies in the Bible probably isn’t advisable, because there is evidence that Son means descendent in some cases (e.g. Rahab of Jericho only the great great grandmother of David, spanning the entire period of the Judges)

  7. “So…how far back can we extend tree ring histories? Well, probably the most reliable, unbroken tree-ring history goes back just over 11,000 years. 3 If you want to get really creative, you can mesh a couple of chronologies together to get a bit over 13,000 years, but at that point, you are making a lot of assumptions.”

    That’s from the dendechrology article you posted, and where I got my 13 thousand years when I echoed the query. Assuming that your data is valid, what do you do with trees that are older than the earth?

    1. Josiah, you missed the fact that trees can grow multiple rings in a year, but they rarely grow no rings. Thus, tree-ring chronologies are prone to give longer ages. A tree-ring chronology of about 11,000 years is consistent with a 10,000-year-old-earth, given the fact that they tend to overestimate the actual age. The 13,000-year-old chronology is very creative, which makes it much less reliable. Even if it is reliable, however, my number of 10,000 years is much closer than the silly number of 4.6 billion years!

      Tree ring chronologies are one big reason I think the earth is older than 6,000 years old.

  8. If I may add a point to Norwegian Shooter’s question, science deliberately gives round,decimal results where possible because of the difference between Accuracy and Precision. Something can be very precise but inaccurate, because the raw data was not that precise.

    For example if someone’s 170 cm tall and weighs 73kg, their Body Mass Index would calculate as 25.259515570934256055363321799308. Giving such a number is rediculous for two reasons: first it makes further calculation difficult, though in the world of calculators this isn’t so important. More significantly the height was only accurate to the nearest cm and the weight to the nearest kilogram. The true BMI might be anywhere between 24.93958600287235231895150540501 and 25.582791656877333124494217766988. What do you do with the sill numbers? you round them off, to give a more reasonable approximation, like 25 (2 S.F. as with mass). That’s enough to tell them they need to lose a bit of weight.

  9. To be honest the tree rings was my least favourite argument. On the one hand the whole way in which overlapping years were located, while seeming sensible, seemed somewhat unreliable in the best of cases. On the other hand trees that don’t fit into a string anchored tree by tree to the present seem too random an element, they could be 500, 10,000 or 20,000 years old with seemingly equal likelihood.

    May I ask what you make of Ice Layers, which seems to be a similar idea of study with a completely different result.

    1. Josiah, it’s interesting that you don’t like tree-ring dating, as I find it very reliable. Using master tree ring patterns to make a tree-ring chronology has been tested against archaeological dating and has been fairly well confirmed, in my opinion. I tend to view the trees that don’t fit into a tree-ring chronology to be simply an indication of the variability of climate and biology. Some trees aren’t sensitive enough to climate to produce master patterns, and some climates aren’t variable enough to produce them. However, if I select the appropriate species and restrict myself to a specific area, the tree-ring patterns all agree with one another.

      Another excellent question from you! You really are good at making connections between data sets and coming up with thoughtful questions. There is a really BIG difference between ice layers and tree rings. In tree rings, the growth is well understood and is the basis of the tree’s biology. Even the fact that trees can grow multiple rings in one year is understood in terms of the tree’s biology. With ice layers, it is completely different. Ice layers do form annually. Unlike tree rings, however, the formation of LATER layers of ice affects the layers that have already formed – the layers already formed are compressed by the layers that form after. The deeper a layer, the more compressed it becomes. As a result, you can’t just count the layers as you go deeper. Instead, you must make models to try to understand how the layers changed as more layers were added above. Only then can you actually “count” the layers.

      Now, of course, models are forced to make assumptions, and one of the assumptions inherent in the models used by those who believe in a billions-of-years-old earth is that the ice sheets being studied have already been there for millions of years, and that, on average, the amount of ice gained by the ice sheet is balanced by the amount of ice lost due to calving and melting. So…is it surprising that researchers can supposedly “count” hundreds of thousands of layers of ice? Of course not. The model ASSUMES they will be there, since the model assumes the ice sheets are millions of years old.

      So notice the difference. I don’t need to make any models to count tree rings. I just need a tree ring core, a good microscope, and a keen eye. For the first couple of thousand ice layers, I don’t need any models, either. Once again, I just need an ice core, a good microscope, and a keen eye. However, after you get past the first few thousand layers, there is no way to continue the count without invoking a model that ASSUMES a millions-of-years-old ice sheet. At that point, you are now assuming an age to get an age, and that is anything but scientific.

      I think another way to see there is a problem with ice layer counting is to look at the difficulties that are involved with interpreting the ice core samples. For example, in order to correlate one ice core to another, all sorts of “offsets” must be used, because the annual layers simply don’t line up. Those offsets are not the same, either. Even when just comparing TWO ice cores, the offsets must vary significantly with depth, sometimes being positive, and sometimes being negative. This is never the case with tree rings. Trees from the appropriate species in the same general area always tell the same story. Ice cores do not.

      Here are a couple of good articles if you want to learn more:

      Do Greenland ice cores show over one hundred thousand years of annual layers?


      Greenland ice cores: implicit evidence for catastrophic deposition

      One final point. Creationists have their own, self-consistent interpretation of ice cores, and it is used to determine specifics about the post-Food ice age. This, of course, indicates that interpretation of ice cores is model-dependent. Creationist have a model of ice layer formation, and they use it to learn about things in earth’s past. Evolutionists have a model of ice layer formation, and they use it to learn about things in earth’s past. Both models have strengths and weaknesses, and neither is probably 100% correct. Nevertheless, both use the same data. Thus, the interpretation of the data is clearly model-dependent. If you want to learn more about the creationist model of ice layer interpretation, there is a rather technical discussion of it in this book:

      The Frozen Record

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