Southern Greenland—warm and ice free!
Evolutionary scientists have recently discovered evidence that southern Greenland was much warmer and ice-free during an interglacial between one of their dozens of glacial periods.1,2 According to the uniformitarian ice age paradigm, Greenland first developed an ice sheet around 2.5 Ma (million years) ago; at the same time the ice sheets supposedly developed on North America and Scandinavia. However, opinion on the timing of the Greenland Ice Sheet is changing. Some scientists believe the Greenland Ice Sheet developed 7 Ma ago,3 while even more recent research claims it was 30–38 Ma ago,4 or even as old as 44 Ma ago!5 These new results are based on the finding of what are believed to be ice-rafted debris in deep-sea cores in the northern North Atlantic.
A warm, ice-free southern Greenland
The basis of the claim of an ice-free southern Greenland comes from the basal silty ice of the 2 km thick southern Greenland Dye 3 core.6 (Figure 1 shows the location of the Dye 3 core on the Greenland Ice Sheet.) The Danish researchers discovered the DNA of a wide variety of plants and insects in the silty ice in the bottom of the core. They were able to positively identify DNA from alder, spruce, pine and yew, and DNA from yarrow, birch, chickweed, fescue, rush, plantain, saxifrage, snowberry and aspen, which could not be independently identified by different laboratories. They also collected DNA from beetles, flies, spiders, butterflies and moths. As a control on whether they could really measure DNA from the foot of a glacier, they successfully identified the DNA from all the plants recently overrun by a glacier on Ellesmere Island, northeastern Canada. They apparently also found DNA in the basal layers of the GRIP core drilled 3 km deep in central Greenland (figure 1), but they were unable to analyze it.
These plants and insects are indicative of warm temperatures, much warmer than is current for southern Greenland. The average July temperature must have exceeded 10°C, and winter temperatures never fell below
Which interglacial was ice-free?
The researchers had to determine which interglacial the DNA came from. They reasoned that the DNA had to originate from the last time southern Greenland was ice-free, because older DNA from previous ice-free interglacials would vanish with the establishment of a new ice-free ecosystem. The basal ice is mixed up, as it is in all basal sections of ice cores. So, glaciologists commonly claim that the basal several metres of dirt and ice can be very old. The researchers used four dating techniques, giving results between 450,000 and 800,000 years. According to the astronomical hypothesis ice ages should repeat every 100,000 years and should have been doing so for the past 900,000 years.9 So these dates would place the last melting of southern Greenland to sometime between the 4th and the 8th interglacial before the current interglacial, the Holocene.
The researchers admitted that there are many assumptions and uncertainties behind their conclusions and they cannot rule out the last interglacial as the ice-free time. Their results are contrary to what most researchers had previously concluded—that ice in southern Greenland had melted during the last interglacial.10–12 That would put the age of the DNA between 115,000 to 130,000 years.13 This interglacial was claimed to be 5°C warmer, with a sea level about 4–6 m higher than today. So, a substantial part of the Greenland Ice Sheet, as well as part of the West Antarctic Ice Sheet, had to melt during the previous interglacial. Hence, many glaciologists have concluded that southern Greenland and probably most of northern Greenland was ice free in the previous interglacial. So, it is likely that these new dates are greatly exaggerated within the uniformitarian paradigm.
Global warming implication
It is interesting that the researchers relate their results to the current global warming.14 They reason that if the last warm interglacial never melted the ice in southern Greenland, then the current global warming, which so far has been only 0.7°C since 1880, will not melt much of Greenland. Andrew Curry states:
‘If southern Greenland remained ice-covered during the last interglacial period, it could mean global warming would have to get much worse before it completely melts away the Greenland ice sheet.’13
This of course depends upon whether the uniformitarian paradigm is correct, and whether the new, but admittedly flawed, dates are accepted.
So much for the evolutionary, uniformitarian interpretation of the data. From a creationist point of view, I would interpret the evidence as showing that Greenland was ice-free for a while after the Flood. Previously I have argued:
‘Since the oxygen isotope ratio at the bottom of the Camp Century core, as well as other Greenland cores … , indicates warmer temperatures, it is possible that snow did not accumulate right away [after the Flood] on Greenland. Being surrounded by quite warm water at the beginning of the Ice Age, glaciation of Antarctica and Greenland likely started in the mountains right after the Flood. It would take some time for the ice sheets to develop over the lowlands.’15
This delay in glaciation would be even longer in southern Greenland, allowing early post-Flood colonization of plants and insects. Furthermore, such warm water at high latitudes surrounding Greenland would keep temperatures much warmer in winter than expected, thus accounting for Yew trees that cannot tolerate temperatures lower than -17°C. It is doubtful whether any uniformitarian scenario can account for such relatively warm winter temperatures during an interglacial in southern Greenland. Greenland truly was green at one time.
The straightforward reading of the Dye 3 ice core supports the creationist interpretation. Figure 2 shows the oxygen isotope profile as being generally proportional to temperature down the length of the Dye 3 ice core. The top 1,700 m, 85% of the ice, represents post-Ice Age ice. The Ice Age portion of the core is represented by the bottom compressed 300 m of ice with a low oxygen isotope ratio. The very bottom of the core at bedrock shows high oxygen isotope ratios. This would represent a warm period, which is where the DNA was found, before the cold period. Notice that there is only one cold period, corresponding to just one ice age after a relatively warm period. This same situation applies to all the deep Greenland ice cores.
In regard to the claim that the ice age cycle of glacials and interglacials started 2.5 Ma ago, Peter Klevberg, Rick Bandy and I analyzed one of those claimed glacial tills dated about 2.5 Ma just east of Glacier and Waterton National Parks in the northwest United States and Canada, respectively.16 The uniformitarian researchers had determined, by relying on a paleosol analysis, that there were about seven glacial till layers alternating with interglacial debris. We determined that the deposits were most likely a huge debris flow deposit that spread eastward from the Parks. We also concluded that the paleosol interpretation was based on questionable assumptions.17,18
Implications for ‘old’ DNA
Willersley et al.1 based their conclusions on finding the DNA of the organisms within organic matter in the silty ice. It is claimed that this DNA is the oldest intact DNA ever found.19 What about all the previous claims for ancient DNA found in many organisms, some dated as being millions of years old, clear back to the time of the dinosaurs? All this apparently has been dismissed; scientists have simply assumed such claims are due to contamination since DNA is destroyed within 100,000 years.13 Contamination is probably a rubber-stamp excuse, but I can believe that DNA would be destroyed within 100,000 years, and probably much sooner. But now the new results from Greenland are being hailed as a new record for the survival of DNA! Here we go again; contamination exists as and when required!
Of course, all that ancient DNA (provided there is no contamination) really is not that old. It originated only about 4,500 years ago, either during the Flood or the early post-Flood period.
References and notes
- Willerslev, E. et al., Ancient biomolecules from deep ice cores reveal a forested southern Greenland, Science 317(5834):111–114, 2007 | doi: 10.1126/science.1141758. Return to text.
- Curry, A., Ancient DNA’s intrepid explorer, Science 317(5834):36–37, 2007 | PMID: 17615317. Return to text.
- Larsen, H.C., Saunders, AD, Clift, P.D., Beget, J., Wei, W., Spezzaferri, S. and OPD Leg 152 Scientific Party, Seven million years of glaciation in Greenland, Science 264(5161):952–955, 1994 | PMID: 17830083. Return to text.
- Eldrett, J.S., Harding, I.C., Wilson, P.A., Butler, E. and Roberts, A.P., Continental ice in Greenland during the Eocene and Oligocene, Nature 446(7132):176–179, 2007 | doi:10.1038/nature05591. Return to text.
- Tripati, A.K. et al., Evidence for glaciation in the Northern Hemisphere back to 44 Ma from ice-rafted debris in the Greenland Sea, Earth and Planetary Science Letters 265(1-2):112–122, 2008 | doi:10.1016/j.epsl.2007.09.045. Return to text.
- Dansgaard, W., Clausen, H.B., Gundestrup, N., Hammer, C.U., Johnsen, S.F., Kristinsdottir, P.M. and Reeh, N., A new Greenland deep ice core, Science 218(4579):1273–1277, 1982 | doi: 10.1126/science.218.4579.1273. Return to text.
- Willerslev et al., ref. 1, p. 113. Return to text.
- Oard, M.J., The Frozen Record: Examining the Ice Core History of the Greenland and Antarctic Ice Sheets, Institute for Creation Research, Dallas, TX, p. 10, 2005. Return to text.
- Oard, M.J., Astronomical troubles for the astronomical hypothesis of ice ages, J. Creation 21(3):19–23, 2007; creation.com/ice-age-troubles. Return to text.
- Koerner, R.M. and Fisher, D.A., Ice-core evidence for widespread Arctic glacier retreat in the Last Interglacial and the early Holocene, Annals of Glaciology 35(1):19–24, 2002 | doi: 10.3189/172756402781817338. Return to text.
- Overpeck, J.T., Otto-Bliesner, B.L., Miller, G.H., Muhs, D.R., Alley, R.B. and Kiehl, J.T., Paleoclimatic evidence for future ice-sheet instability and rapid sea-level rise, Science 311(5768):1747–1750, 2006 | doi: 10.1126/science.1115159. Return to text.
- Otto-Bliesner, B.L., Marshall, S.J., Overpeck, J.T., Miller, G.H., Hu, A. and CAPE Interglacial Project members, Simulating Arctic climate warmth and icefield retreat in the Last Interglacial, Science 311(5768):1751–1753, 2006 | doi: 10.1126/science.1120808. Return to text.
- Curry, ref. 2, p. 37. Return to text.
- Oard, M.J., Global warming—examine the issue carefully, Answers 1(2):24–26, 2006. Return to text.
- Oard, ref. 8, p. 47. Return to text.
- Klevberg, P. and Oard, M.J., Drifting interpretations of the Kennedy gravel, Creation Research Society Quarterly 41(4):289–315, 2005. Return to text.
- Klevberg, P., Bandy, R. and Oard, M.J., Investigation of several alleged paleosols in the Northern Rocky Mountains—Part I: background and methods, Creation Research Society Quarterly 44(1):4–25, 2007. Return to text.
- Klevberg, P., Bandy, R. and Oard, M.J., Investigation of several alleged paleosols in the Northern Rocky Mountains—Part II: additional data and analysis, Creation Research Society Quarterly 44(2):94–106, 2007. Return to text.
- Uni. Copenhagen, Oldest DNA ever recovered suggests earth was warmer, July 2007, physorg.com. Return to text.
- Oard, ref. 8, figure 1.1, p. 3. Return to text.
- Oard, ref. 8, figure 2.6, p. 23. Return to text.
- Vardiman, L., Climates Before and After the Genesis Flood: Numerical Models and Their Implications, Institute for Creation Research, Dallas, TX, p. 57, 2001. Return to text.