Scientists took hundreds of DNA samples from the ice 2km deep at the base of the southern Greenland ice sheet. They found DNA from species such as alder, pine, spruce and yew trees. They also found DNA from beetles, butterflies, flies and spiders.
According to the scientists, the DNA is at least 450,000 years old. It shows that Greenland was very different at the time from what it is today, that it was covered with forest very comparable to the forests in eastern Canada.
According to researcher Eske Willerslev of the University of Copenhagen in Denmark, this discovery fills a big gap in our knowledge of how life looked like in regions that are now covered by ice before the ice was formed. Approximately 10% of the earth's surface is covered in ice.
They suppose that mammal DNA could also be found, if they extend their searches further. Plant DNA survives better in permafrost, probably simply because there are more plants than mammals.
This is certainly very interesting, but it also raises questions about current climate models. According to a respected 2006 modelling study by Bette Otto-Bliesner of the American National Center for Atmospheric Research, the site where the DNA samples come from was not covered in ice about 120,000 years ago during the last interglacial period.
According to the latest report by the IPCC temperatures in the Arctic were 3 to 5 degrees Celsius warmer than today and the sea levels were 4 to 6 metres higher than today during the last interglacial period. The water for this was supposed to come from Greenland.
This data is clearly inconsistent with this new discovery of DNA. The researchers say that they used 4 different dating methods and that these all resulted in date ranges that overlap each other. Therefore, the DNA must be older than the last interglacial period because the ice at the bottom of the sheet is between 450,000 and 800,000 years old.
If the tests are correct, and there is no reason to doubt that, the climate modelling study must be wrong, meaning that there was ice on the site after all.
The significance of this all will probably become clear in the future, but, in my opinion, it clearly shows that climate models are very far from perfect, and that this is one further indication that the theory of human caused global warming is nothing more than that: a dubious theory based on very shaky data. It might be true, but it may just as well not be.
DNA on Greenland, and what about global warming?
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