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Greenland used to be green

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The skeptic argument...

"Sallie Baliunas, a co-author of a 2003 study, 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)

What the science says...

The Greenland ice sheet has existed for at least 400,000 years. There may have been regions of Greenland that were 'greener' than today but this was not a global phenomenon.

This argument is based on the idea that as climate has changed naturally before, current climate change must be natural also. The obvious flaw in this argument is that the main driver of climate during the Medieval Warm Period (eg - solar variations) cannot be causing global warming now. More on the "Climate's changed before" argument...

Did Greenland used to be green?

The Greenland ice sheet is at least 400,000 to 800,000 years old. Certainly it was alive and well when the island was named around 1000 years ago. So where did the Green in Greenland come from? According to Wikipedia, legend has it was good marketing on the part of Erik the Red who figured it would attract more settlers (if he was more vain, it may have been called Redland). Or perhaps its a derivation of Engronelant or Gruntland. The main point is while the ice sheet has always been there, Greenland probably was somewhat warmer during the Medieval Period and part of Greenland was green. So once again, I refer you to the Climate's changed before argument.

Ancient Greenland DNA

I recommend reading what the authors are actually saying about their own study. The study connects past warming to natural variations in Earth's orbit—obliquity, or how tilted the planet is in relation to the sun. Author Martin Sharp points out "One could argue that this shows that natural forcing could account for the current warm conditions, but the current orbital configuration does not support this, even when other natural forcings are taken into account." In other words, their study "really has nothing to say about the mechanisms driving the current warming."

According to author Eske Willerslev, the Greenland ice shelf "has not contributed to global sea level rise during the last interglacial. Importantly, it does not mean that we should not be worried about future global warming as the sea level rise of five to six meters during the last interglacial must have come from somewhere."

Finally, Martin Sharp warns the study "does not prove the current global warming trend is not human induced". If anything, "we may be heading for even bigger temperature increases than we previously thought".

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Comments

Comments 1 to 11:

Alan McIntire at 13:31 PM on 26 December, 2007
There's a recent paper on Greenland:

AB: Radiocarbon dates of emergent organic remains along the western margin of Istorvet ice cap (70.8°N, 22.2°W) indicate a time when the ice cap was smaller than at present. This ice cap, similar to others in east Greenland, exhibits "historic" moraines ~1-2 km in front of the presently retreating ice margins....

Moreover, it indicates warm conditons at this latitude at the time of Norse colonization of Greenland."
Wondering Aloud at 12:10 PM on 5 March, 2008
Now this may seem off topic but I have read that the name Greenland was a propaganda tool used to attract settlers. The Norse definitely had farms there during the MWP and they appear to have been frozen out after seveal generations when the harbor stopped thawing regularly, but that doesn't mean it was ever a sunny vacationland. They also dubbed the Labrador cost Vinland, but I don't recommend relocating your winery there. Iceland was the opposite idea.

The reason I came here is to ask the question where do we look to see where the earth is today on all these reported orbital and processional cycles and where is the earth in these cycles during an ice age?
Response: NOAA have a page on Milankovitch cycles including links to data & papers on the subject. I haven't read them, let us know if you find something interesting.
Quietman at 04:29 AM on 26 August, 2008
It has been proven that Greenland was in fact greener than today. The Glaciers had receded (not disappeared) enough for the lowland areas to be fertile and climate temperate. The argument for the age of the glaciers is a little absurd since we know that it was not a hot house, just somewhat warmer than it is now, enough to be comparable with Iceland or Finland of today, ie. habitable by the vikings.
Quietman at 04:32 AM on 26 August, 2008
WA
If it was a propaganda tool they would not have named iceland as such. We still can't locate vineland due to the cooling since the discovery.
wp at 19:03 PM on 26 August, 2008
"If it was a propaganda tool they would not have named iceland as such."

Possibly because the places were named by different people, 100 years apart?
Quietman at 02:22 AM on 29 August, 2008
wp
Possible but not probable. Vineland was named by the greenlanders of that time, we can't identify it to this day because the climate changed.
Mizimi at 05:16 AM on 9 December, 2008
#5 'Iceland' is from the old Norse word meaning 'isle' co-joined to 'land' thus giving (phonetically) 'iceland'
Quietman at 14:17 PM on 25 February, 2009
From the NOAA link in the response to comment 2:

"What does The Milankovitch Theory say about future climate change?
Orbital changes occur over thousands of years, and the climate system may also take thousands of years to respond to orbital forcing. Theory suggests that the primary driver of ice ages is the total summer radiation received in northern latitude zones where major ice sheets have formed in the past, near 65 degrees north. Past ice ages correlate well to 65N summer insolation (Imbrie 1982). Astronomical calculations show that 65N summer insolation should increase gradually over the next 25,000 years, and that no 65N summer insolation declines sufficient to cause an ice age are expected in the next 50,000 - 100,000 years ( Hollan 2000, Berger 2002). "

Don't these "scientists" know the difference between an ice age and a glacation? We ARE in an ice age. So I guess they mean it will end in 50K years or will it reach another glacial maximum? - From the people that brought you AGW.
thingadonta at 20:13 PM on 11 July, 2009
Greenland was relatively warm between about 800-1300 AD due to the well-defined 1500 year solar cycle, as detailed by Singer and Avery in:

"Unstoppable global warming every 1500 years".

We are currently in another upswing in the solar cycle, which started about 1750, and which will probably rise about another 0.5-1 degree C over the next few hundred years. Current T to the 21st century is entirely in line with this solar cyle trend. C02 is irrelevant to this cycle,it has been traced 600 times over the last 1 million years in ice cores, and is a result of an overlap between the 87 and 210 year solar cycles.

It is well documented, world wide, and climatologists have conveniently forgotten about it (see reference given above).

Greenland was settled by vikings during the last solar warming period, which is also why they travelled so far in general during this time period-the northern world was warm.
chech1965 at 00:30 AM on 23 July, 2009
WP

Vinland has been found. It's Lanse Aux Meadows on the Northern Peninsula of Newfoundland where Norse settlements were discovered in the 60s.

The mistranslation of Vinland leads many like yourself to think that it means "wine" when in fact, it's a Norse word for "meadow."

Which is where Lanse Aux Meadows gets its name today.

Iceland was named that before they realized that naming something "Ice" land would deter settlers. Greenland was an attempt to correct that.

And, thingadonta, I suggest you check out the argument "it's the sun." Fred Singer is the last person on Earth that you should be listening to when it comes to climate change. He is the same Singer that was also a "expert" when it came to the tobacco industry and proclaimed that second-hand smoke was not harmful to our health.

Guess how that worked out?

You should get your facts from the climate scientists, not those paid by the energy sector to be experts in the field:

http://www.realclimate.org/index.php/archives/2006/11/avery-and-singer-unstoppable-hot-air/
oracle2world at 13:27 PM on 8 March, 2010
So let me get this straight. A warmer Greenland was a "local phenomenon", but twelve trees in a Siberian forest suffice to represent centuries of global temperature?