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Greenland used to be green

What the science says...

Select a level... Basic Intermediate

The Greenland ice sheet is at least 400,000 years old and warming was not global when Europeans settled in Greeland 1,000 years ago

Climate Myth...

Greenland was green

“CfA's Sallie Baliunas […] refers to the medieval Viking sagas as examples of unusual warming around 1003 A.D. ‘The Vikings established colonies in Greenland at the beginning of the second millennium, but they died out several hundred years later when the climate turned colder,’ she notes.” (William Cromie)

Greenland is a large area situated east of Canada, between the Arctic and Atlantic oceans. About 80% of the island is covered by the Greenland ice sheet. During the 980s, Scandinavian and Icelandic exporers established two or three settlements on the south-west coast of Greenland. So what were the conditions in Greenland like 1,000 years ago? More precisely, let's explore the three following questions:

  1. How old is the Greenland ice sheet?
  2. Is there evidence of global warming at that time?
  3. What factors cause climate change?

The Greenland ice sheet is at least 400,000 years old

Scientists have estimated that the Greenland ice sheet is between 400,000 and 800,000 years old. This means that the island today is unlikely to have been markedly different when Europeans settled there. However, there is evidence that the settled areas were warmer than today, with large birch woodlands providing both timber and fuel. This warmth coincided with the period known as the Medieval Climatic Anomaly, also known as the Medieval Warm Period, which we will discuss below.

So how did Greenland get its name? According to the Icelandic sagas, Erik the Red named it Greenland in an attempt to lure settlers in search of land and the promise of a better life. However, the age of the ice sheet, which is more than 3 kilometres thick in places and covers 80% of Greenland, proves that the opportunities to establish communities would have been limited to rather small areas.

Warming during the Medieval Climatic Anomaly was not global

During the Medieval Climatic Anomaly, some areas, most notably in the North Atlantic and parts of Europe, were at least as warm as today, if not warmer. However, other areas were colder, and overall evidence suggests that global temperatures during this period were similar to those at the beginning or middle of the 20th century, and colder than today. This period is explored in more depth here.

So not only was Greenland already mostly covered in ice when Europeans settled there, but also the relatively warm conditions during this period were not a global phenomenon. This contrasts  with what we are seeing today, where warming is truly global. Figure 1 is a map showing reconstructions of temperature anomalies during the Medieval Warm Period. Blue colours show lower temperatures and warm colours show higher temperatures when compared to the 1961-1990 reference period.

Reconstructed surface temperature anomalies for the Medieval Warm Period

Figure 1 - Reconstructed surface temperature anomalies for the Medieval Warm Period (950-1250) compared to a 1961-1990 reference period. (Source: Mann et al., 2009)

We can compare this with a similar reconstruction looking at surface temperature anomalies for the 1999 to 2008 period. This clearly shows the global nature of recent warming.

Surface temperature anomalies from 1999 to 2008

Figure 2 - Surface temperature anomaly for period 1999 to 2008, relative to the 1961– 1990 reference period. (Source: NOAA)

Natural versus man-made climate change

Warming can be the result of a number of factors, so that the cause of past climate change is not necessarily implicated in current climate change. For instance, the Medieval Climatic Anomaly was characterised by relatively high solar activity, low volcanic activity and possible changes in ocean circulation patterns. These factors can explain both the scale and pattern of warmth at that time. However, they cannot explain recent warming. More to the point, changes in natural factors would probably have led to cooling in the past few decades. This contrasts with the multiple lines of evidence pointing to the role played by humans in recent warming, as illustrated by the the graph below.

Graph showing the human fingerprints on global warming

Conclusion

Greenland is unlikely to have been radically different 1,000 years ago since the ice sheet is at least 400,000 years old. So the evidence shows that not only was Greenland not green, the warmth was mainly a regional phenomenon caused by natural factors. Compare this with the unequivocal findings of the scientific community regarding ongoing warming: climate change now is global and in all likelihood driven primarily by human activities.

 The key points can be summarised as follows:

  • The Greenland ice sheet already covered large sections of Greenland when Europeans established communities there 1,000 years ago
  • Warming was not global during the Medieval Climatic Anomaly; average global temperatures were lower than today
  • Natural factors behind regional warming in medieval Greenland are probably not responsible for today's global warming

Basic rebuttal written by dana1981


Update July 2015:

Here is a related lecture-video from Denial101x - Making Sense of Climate Science Denial

Last updated on 15 May 2016 by pattimer. View Archives

Printable Version  |  Offline PDF Version  |  Link to this page

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Comments 26 to 34 out of 34:

  1. Thank you for posting.

    I agree with the topic, Greenland used to be green. When Greenland has discovered and named by Erik the Red about 1,000 years ago, it will be different from now. If there is no any evidence that show Greenland was green, he would not name this place as Greenland. The DNA is proof that sometime between 450,000 and 800,000 years ago, much of Greenland was especially green and covered in a boreal forest that was home to alder, spruce and pine trees, as well as insects such as butterflies and beetles (From: https://www.livescience.com/7331-ancient-greenland-green.html). And from the map, like Google map or map in Wikipedia we can see that the edge around Greenland is still green. Greenland ice sheets is between 400,000 and 800,000 years old. So, Greenland today will maybe different from the past. Because of the global warming. Global warming not just changing Greenland, but it affects all over the world. One of the main driven of global warming is from human activities. We have to cooperate together, help each other to reduce global warming before it too late. And I also have some questions. As you can see in the map that at the edge of Greenland is green, I want to know why it’s not cover of ice? And is it true that Greenland now is greener than in the past?

  2. randman, your comment doesn't make sense to me. The map comes from a peer-reviewed scientific paper by a team of 9 scientists. Are you accusing the scientists of fraud...? The paper says it used a "diverse multiproxy network" documented in Dataset S1 of the Materials and Methods supplement associated with the paper. That'll be the observations, or in other words, evidence, upon which the map is based.

  3. "Greenland used to be green. When Greenland has discovered and named by Erik the Red about 1,000 years ago, it will be different from now. If there is no any evidence that show Greenland was green, he would not name this place as Greenland"

    The climate was already cold in Greenland at that time. In fact, the climate was so inhospitable that the few survivors of the Viking settlements left rather than die there.

    The Vikings did farm, but they farmed in two settlements in limited coastal fringes, and it was worse-than-subsistence farming (because the farming and building eroded the fragile top-soil). The same sort of farming seems to have been possible for much of the intervening time, therefore the farming cannot be taken as direct evidence of warmer conditions. The Vikings did so well at farming that they died doing it while the local Inuits still thrive today.

    The Viking settlements did not get buried under glaciers (Google Hvalsey Church). One got buried under wind-blown sand. Thus the failure of the settlements cannot be taken as direct evidence of cooler conditions. The portions of Greenland not immediately adjacent to the ocean have been continuously covered in ice sheets for tens of thousands to hundreds of thousands to millions of years.

    If you want further proof and readings about what the Viking settlements failed, read Jared Diamond's "Collapse". Diamond refers to several book-length accounts, but a shorter older account is Magnus Magnusson's "Vikings" (1980).

    Evidence exists of an ice sheet of at least some extent in a Greenland for at least 2.7 million years.

    Further, recent research confirms that the Vikings’ mysterious abandonment of Greenland was not due to climate change.

    And then there's this:

    "the Greenland Norse were "not a civilization stuck in their ways." To NABO archaeologist George Hambrecht of the University of Maryland in College Park, "The new story is that they adapted but they failed anyway.""

    And

    "Despite the signs of crisis at a few Western Settlement sites, those in the Eastern Settlement show no sign of a violent end. Instead, after farmhouses collapsed, remaining settlers scavenged the wood from them, suggesting a slow dwindling of population. The challenge for the average Greenlander to survive drove "a constant emigration" back to Iceland and Europe, Fitzhugh hypothesizes, "which could bring the Eastern [Settlement] to a close peacefully, without starvation or death by Inuit.""

    As for this question of yours:

    "is it true that Greenland now is greener than in the past"

    It is likely true that Greenland is now greener than it has been for some 4,000 years.  Because the warming of the past 100 years (driven by human activities) has erased a natural cooling of some 4,000+ years:

    NH Temperatures

    Legend

    Larger image here.

  4. In the Greenland section of Jared Diamond's book "Collapse", he describes the Norse settlements in Greenland as failing owing to cultural factors rather than climate.

    The rise & spread of Muslim power (in Africa and the Middle East) blocked or impeded the European import of elephant ivory.   Consequently the Norse Greenlanders initially became quite wealthy by harvesting and exporting walrus ivory to Western Europe.  But that trade later altered as "geopolitics" changed. 

    Some aspects of Norse farming methodology were not well suited to Greenland conditions, and there was necessarily a swing to more reliance on wildlife hunting and especially the harvesting of seals.

    The Norse despised the aboriginal Inuit as heathen & uncivilized.  Intermarriage with Inuit and prudent diplomatic relations with Inuit did not happen.  The reverse — there were increasing hostilities with the Inuit, skirmishes and even some pitched battles (casualty numbers small but of course higly significant for such a small population of Norse.   *IIRC*, Diamond equated the Norse warriors lost in the worst battle, as representing the U.S. Army losing 3 million men in a single battle).

    In short, the Norse failed to live with their Inuit neighbours and failed to make full use of the "technology" which had sustained the Inuit in Greenland over thousands of years.   A lesson for us all.

    Even today, the 60,000 Greenlander population is 90% Inuit — though the economy is supported by fishing using modern technology.   And, as in northern Canada, there is a high level of demoralization, suicide & alcoholism — a result of the social climate, not the physical climate.

  5. Daniel Bailey:

    "If you want further proof and readings about what the Viking settlements failed, read Jared Diamond's "Collapse"…"

    ...and Eclectic:

    "In the Greenland section of Jared Diamond's book "Collapse", he describes the Norse settlements in Greenland as failing owing to cultural factors rather than climate.

    The rise & spread of Muslim power (in Africa and the Middle East) blocked or impeded the European import of elephant ivory. Consequently the Norse Greenlanders initially became quite wealthy by harvesting and exporting walrus ivory to Western Europe. But that trade later altered as "geopolitics" changed.

    Some aspects of Norse farming methodology were not well suited to Greenland conditions, and there was necessarily a swing to more reliance on wildlife hunting and especially the harvesting of seals.

    The Norse despised the aboriginal Inuit as heathen & uncivilized. Intermarriage with Inuit and prudent diplomatic relations with Inuit did not happen. The reverse — there were increasing hostilities with the Inuit, skirmishes and even some pitched battles (casualty numbers small but of course higly significant for such a small population of Norse. *IIRC*, Diamond equated the Norse warriors lost in the worst battle, as representing the U.S. Army losing 3 million men in a single battle).

    In short, the Norse failed to live with their Inuit neighbours and failed to make full use of the "technology" which had sustained the Inuit in Greenland over thousands of years. A lesson for us all..."

    Using Daiamond's Collapse is problematic.

    1) Diamond's argument (actually, McGovern's, see "The Fate of Greenland's Vikings", Archaeology) that the Norse should have adopted the toggle harpoon for ring seal hunting ignores that fact that even the Inuit (Eskimos) couldn't make them work for coastal fishing during this time, since the ice wasn't thick enough (see Gad, History of Greenland, Vol. I, p. 166).

    2) Diamond's (and McGovern's) claim that Greenland Norse didn't fish is ridiculous. When asked by a journalist, the archaeologist Jette Arneborg literally laughed (see Brown, The Far Traveler, 153). If Diamond had properly studied the Farm Beneath the Sands study, he would have realized that the reason so few fish bones were found is that they are very fragile, so the archaeologists weren't even looking for them at first. Once they started, despite the inherent difficulty, they found them (Enghoff, 7, 19, 48, 88). They also ignore Greenland Norse fishing gear, and the Norse accounts of fishing.

    3) Diamond claims that the Norse over-forested and -grazed Greenland. Georg Nyegaard studied a Norse farm, and found it had minimal effect (see his talk with Brown in The Far Traveller, 159-160). It certainly wasn't bad enough to drive the Norse to starvation. Even Diamond admits that there is evidence for only one Greenland Norseman who may possibly have starved to death (Collapse, 267), even as he describes the easily found evidence for entire families of the supposedly well adapted Inuit starving to death in their igloos (264, 273). Apparently, the guys who weren't starving to death in droves were supposed to take tips from the guys who were.

  6. Part II...

    4) As for Norse relations with the Inuit, we have the Inuits' recollections (see Rink's Tales and Traditions of the Eskimo). The Inuit themselves paint a mixed picture of relations with the Norse, sometimes friendly, sometimes hostile. It probably varied from tribe to tribe and time to time. They certainly didn't think of the Norse as maladapted. Diamond also mischaracterizes a case of an Inuit, who was found mortally wounded after a raid on a Norse settlement, as the victim of some Mengele-like medical experiment (see Gad).

    As for why the Norse settlement failed, the arrival of the Little Ice Age didn't help, nor did occasional fighting with the Inuit (and possibly the Basque), but there were other factors. The Norwegian government placed high taxes on trade with Greenland, and required visiting traders to buy Greenlandic goods, which hardly helped. The biggest factor was the competition for walrus ivory with elephant ivory during the 14th Century. Greenland simply went bust, like many a boom economy.

  7. JDG @31 ,

    I certainly agree with your last paragraph.  (But not so much your final sentence ~ "boom and bust" sounds like a business sector.  The Greenland Viking saga was closer to "extinction event". )

    From a climate point of view, it was a rather small decline in temperatures from the Medieval Warm Period . . . and it should not have been enough to extinguish the Viking colonies.

    As you have noted, it was a combination of factors (including a failure of appropriate adaptation) which caused the collapse.  I used the word "geopolitical" as an umbrella term for the various events: an increasing southward push by the Inuit; taxational pressure from Copenhagen; increased competition from Russian suppliers of walrus ivory & renewed elephant ivory supplies from Africa.   Including a societal change in Europe ~ there was a gradual fall-off in demand for ivory as a luxury good.

    Like the average plane crash: a number of adverse circumstances came together.  

    The climate Take-Home Message is that the decline of the MWP was too trivial a matter to finish off the Greenland Vikings.

  8. I was just looking around for some discussion around the topic of origin of the name Greenland and it's striking to me that people uncritically use the

     

    "Because," said he, "men will desire much the more to go there if the land has a good name."

     

    as any argument. It's a huge jump to conclusions.

     

    If a company releases a product named "ecofleebus" trying to market it as a very ecological fleebus how can one hop to conclusion that this fleebus has no ecological design aspects to it at all? Quite the opposite - for marketing to work, it has to be very believable. Marketing is more about exagerating, over-selling, etc. and rarely about calling black color white.

     

    Men will desire to go somewhere if it has an appealing name. No duh. Doesn't mean such appealing name is complete lie.

     

    So while it's still a huge guesswork, I think it's far more likely to assume that Greenland was "green enough" to try to "(over-)sell it".

  9. dpc @33,

    The original name for Greenland was Inuit Nunaat meaning 'country of human beings'. So perhaps there was once a burgeoning population living there. Or perhaps such names are poor descriptors which would be why, apparently, "people often say that Iceland and Greenland should switch names since Iceland is green and Greenland is so icy."

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