Fitting the ice age into creationism – Misguided Mondays

Over the past week or so several creationist sites have written about how the ice age fits into the Biblical chronology. The most prominent of these being Answers in Genesis, who wrote a “special feature” on the matter. This trend is rather surprising given that, as the sensuous curmudgeon eloquently notes, there are only a scattering of references to “ice” in the Bible and none to any long period of glaciation.

Despite this lack of Biblical support Answers in Genesis believes there is enough secular evidence to prove there was indeed an ice age. So they attempt to create a narrative of this period in the earth’s 6,000 year history based on purely science! Be warned, that way lie dragons.

They weave a grand story, of how

As a massive ice sheet expanded over Canada, it drove out most living things, and then it continued to push south into the Ohio valley. Eventually, the heavy snows stopped and the earth warmed. Once the ice began to melt, animals returned to Big Bone Lick, along with spear-wielding humans.

The timeframe given for this dramatic sequence of events is 250 years or so. Since this is a narrative based on science we can use palaeoclimate data to help flesh out this description of the Biblical ice age.

Scientifically speaking, the period we’re looking at is the Pleistocene, which was the last era during which glaciers covered  significant portions of the earth. Traditionally this period is thought to have lasted from 2.6 million years ago until ~10,000 years ago; although AiG has condensed this down into their neat 250 year time frame.

We have many ways of investigating the palaeoclimate during the Pleistocene. For example, isotope ratios (variants of elements with a different number of neutrons) in the ocean vary with the climate. These isotopes are incorperated in the shells of microscopic marine organisms, providing a snapshot of the ratio (and climate) during their life. This isotope data can also be obtained from arctic ice and caves across the world. Sediment which forms under glaciers is different from that which does not, allowing us to track how far they extended (and when). Pollen records shows us what kind of plants were living in an area, telling us what the environment was like and what was living there.

All of these lines of inquiry correlate. When isotopes indicate that there was a warmer period we find evidence glaciers retreated and pollen records tell us warm adapted plants spread further north, colonising previously inhospitable environments. The opposite is also true, with the disappearance of these warmth-loving plants coinciding with glacial expansion and appropriate isotope variation. The fact that these independent pieces of evidence all agree with each other provides strong evidence they are accurate. Whilst Answers in Genesis may quibble over the length of time these climate records represent, surely they cannot reasonably quarrel with the accuracy of the story they tell.

This raises something of a problem for the creationists. You see, this climate evidence shows that the single, grand glacial expansion AiG talks of simply didn’t happen. The ice age was full of multiple periods of warm and cold, corresponding with glaciers retreating and expanding several times (and associated changes in the vegetation). Graphs showing the temperature during the ice age typically look like this:

Pleistocene temperature relative to today. X-axis is omitted because that's the bit the creationists would debate. From Bintanja & de Wal

Pleistocene temperature relative to today. Left is present day, right is start of Pleistocene. Specific dates are omitted because that’s the bit the creationists would argue over. From Bintanja & de Wal

On this graph “0″ refers to the present day temperature (you can just see the tiny spike on the left that is the climate we’re experiencing). As you can see there were several periods where the temperature during the ice age was the same as it is today! There were many, many climate oscillations as the earth fluctuated between cold glacial and warm inter-glacial. As you might expect this also means there was extensive variation in the size of glaciers during the ice age.

Ice coverage of the earth during part of the Pleistocene relative to today. Same deal as previous graph, even from same source!

Ice coverage of the earth during part of the Pleistocene relative to today. EAS = Eurasia, NAM = North America. From Bintanja & de Wal

That graph tells of how much ice there was on the earth during part of the ice age. Like the prior graph the values are relative to the present, so 0 = the same as the modern day. As you can see there are periods during the ice age where glaciers in North America are no bigger than they are today. The rest of the world also gets pretty close to present day glacial coverage at several points.

So the climate was a lot more varied than Answers in Genesis suggests, so what? The thing is that all of this variation has to be condensed down into the 250 year ice age they give. This data comes from Pleistocene deposits which they acknowledge were formed during the ice age, so must be squeezed into the period they claim the ice age happened in. The first graph records over 100 significant changes in the climate, 34 of which are considered to be major shifts.

Under the creationist model this amounts to significant climate change every couple of years or so, with big changes occurring roughly every 7 years. This means that Answers in Genesis wants you to believe that entire forests can become established in a few years and that glaciers will grow to huge sizes in less time than it takes a child to reach the 1st grade. The speed at which climate change must occur for the creationist model to remain valid is simply absurd.

No doubt that Answers in Genesis can conjure up some special pleading explanation to resolve this issue. Maybe less “damage” to the DNA as a result of original sin had accumulated, allowing plants to grow quicker than in the present. Ken Ham – president of AiG – has already endorsed an Atlantis-esque mythology claiming that Noah had more advanced technology than we do because his brain hadn’t been harmed by such damage.

However, when they start concocting such excuses their attempt to be scientific has thoroughly failed.  Trying to come up with a scientific model for creationism results in absurdities that must be magicked away. When will they realise it’s actually creationism which needs to disappear?

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24 thoughts on “Fitting the ice age into creationism – Misguided Mondays

  1. You have an interesting post. In all that I have seen, debates with fundamentalists normally turn into flame wars with “no end.” I guess the worst error in their judgment would be to take bits and pieces of good science and apply it to meet their own ends.

    • As this article hopefully shows, cherry picking certain aspects of science is the only way creationism can remain viable. Yet as you correctly point out, doing so is a bad thing. Ultimately it shows that their view is unscientific

  2. Hey Adam,
    just wondering…did I miss something, is there a serious challenge to out of Africa and mitochondrial Eve?
    Colin

    • Out of Africa has been refined and updated a bit recently (such as to include interbreeding between different species and repeated waves of migration) and the dates of various mitochondrial divergances have been redated too (which have also lead to redating of out of Africa) but I’m not aware of anything in particular that offers a substantial challenge to them. If there’s something you want me to take a look at then by all means post a link.

      • It was just a conversation with a friend, he was suggesting that there was no mitochondrial Eve, that mitochondrial transfer has been linked to males, and that there were perhaps concurrent occurrences of sapien sapiens with a separate line emerging (evolving?) in Australia.

        • I think it does seem to be the case that mtDNA inheritance is a bit more complicated than previously believed, but from what I can tell these additional factors play a small role and so don’t directly challenge mtEve herself (although they may result in slight refinements to the idea).

          As for the Australian evolution, the ancestry of all living humans has been traced to Africa so we know that’s not the case. However, we do find some modern humans outside of Africa prior to the “out of Africa” migrations are supposed to have occurred. This suggests that there was some multi-regional development (which we out-competed when we left Africa) or that there were earlier, failed migrations by our species. The evidence indicates the latter, but the finds are often too fragmentary (and rare) to say for sure.

  3. Genesis chapter 8 verse 22 (New International Version): ““As long as the earth endures, seedtime and harvest, cold and heat, summer and winter, day and night will never cease.””. Is the YEC ‘rapid recent ice age’ refuted by the Bible itself?

    • That reference to “harvest” is curious. Under their model, Noahs flood occurred before the Plesitocene, so this line suggests that people would’ve been farming prior to this period. Yet we find absolutely no evidence for such activities until after ice age. Hell, we find no evidence of modern humans prior to the Pleistocene.

      • Adam
        Yes, indeed. Genesis chapter 4 verse 2b (New International Version): “Now Abel kept flocks, and Cain WORKED THE SOIL”.

        • Domesticated animals are typically defined as being a separate species, having been changed from their wild counterparts by years of human-based selection. So either domesticates were created at the beginning of time (which would really throw a spanner in the works of everything in the garden of eden only eating plants. Why then create a separate species of animal for human consumption?); or they were domesticated after the fall. Whilst the former may be scripturally absurd the latter is scientifically absurd. Since domestication involves the emergence of a new species it takes many generations, often thousands of years (unless intensive artificial selection is employed). So for them to have domesticated animals within a generation is just stupid.

  4. “When will they realise it’s actually creationism which needs to disappear?” Never (not publicly anyway). But their descendants might.
    By the way they always call it an ice age rather than, correctly, an ice age glaciation (technically we are still in an ice age – and I can probably find some recent pictures of Derbyshire or County Down that APPEAR support that notion – ‘observational science’).

    • But by calling it a glaciation reveals that the ice age itself was variable which, as I mentioned, highlights the absurdity of their position. The thing is one of the authors appears to be a professional geologist, he should know about the plethora of evidence that indicates the Pleistocene was a variable period.

  5. Epistemologically challenged here: How do we know that isotopic signatures in corals, etc, reflect climate? Was it *because* these correlated with interglacials? If so, doesn’t that make it more difficult to use the correlation to claim that multiple lines of truly independent evidence indicates changes in climate? I’m not a geologist and I don’t know just how independent the lines of evidence are.
    This is part of a broader question about claiming that our model of the world is more than just internally consistent (understanding that internal consistency itself is more than the YECs could ever achieve).

    • It took me a while to wrap my head around it too. Basically, the different isotopes have different molecular weights because they have different numbers of neutrons. In the oceans, lighter isotopes rise to the surface and so tend to be preferentially evaporated. If the evaporated isotopes don’t return to the ocean because they get frozen in glaciers, oceans will thus have a higher proportion of heavier isotopes (which will be reflected in the animals living in them).

      This method, as you can tell, is very different from, say, looking at the flora and fauna of a landscape to work out what the environment was during a particular period, yet they both tell the same story.

      • Thanks, that’s something cool that I didn’t know. But do you know if validation of the isotope evaporation model for reconstructing paleoclimates was independent of the observed stratigraphy of flora and fauna that otherwise define the glacials/interglacials? I’m just guessing (sorry) that information regarding how the isotopes should be interpreted is based at a fairly fundamental level upon the very distinct source data from pollen, etc. If so then we’d have different lines of evidence contributing to a consistent understanding, but not fully independent lines of evidence.
        …I think.
        Best wishes.

      • I’m no expert on the early days of marine isotope analysis, but from what I can tell the early research was carried out by ocean scientists just interested in what influenced isotope ratios in the ocean, rather than by people trying to figure out what the ancient climate was.

        Ocean scientists theorised that evaporation would influence the isotope ratios, as mentioned above, and conducted experiments to see if this was the case (it was). Palaeoclimate scientists then realised that such evaporation (if the evaporated water was locked up in glaciers) could lead to long term changes in isotope ratios. They predicted that such changes should thus be correlated with glacial periods, went looking for them in the ancient record and found that they matched their expectations.

        I’ll leave it down to you to decide if that’s truly “independent” or not.

  6. Adam and others may be interested to see my most recent comments here (mainly those about the details of how Answers Magazine ‘answered’ questions about their ‘biblical ice age’ during their ‘live chat’ on Tuesday):
    http://forums.bcseweb.org.uk/viewtopic.php?f=1&t=2970&start=450

    My very latest post flagged this interesting new blog post (written by a Christian who isn’t anti-science): http://geochristian.wordpress.com/2013/04/16/an-answers-in-genesis-chat-about-ice-ages/

    • I was hoping that Facebook group would provide some fodder for future posts, but it was really a poor event. Many good questions, no really good answers (certainly none really worthy of consideration). Do you know of any other Facebook events in the future?

  7. Pingback: How can isotopes tell us about the prehistoric climate? | EvoAnth

  8. Pingback: Creationists say Ice Age was 250 years and that's scientifically crazy - Baltimore Post-Examiner

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