Why didn't Antarctica and Greenland melt down during the Holocene maximum?

Question

The Holocene maximum peaked about 6000 years ago. It was much warmer than it is now and it lasted for about 4000 years, but the ice cores show that Ice existed on those continents for more than 500,000 years.

http://www.lakepowell.net/sciencecenter/paleoclimate.htm

http://en.wikipedia.org/wiki/Ice_cores

Here is what the NASA website has to say about the Holocene maximum:

"We think it was quite a bit warmer then," he observes, noting that geochemical analysis of the sediment also revealed higher levels of nitrogen during the mid-Holocene."

http://earthobservatory.nasa.gov/Newsroom/MediaAlerts/2001/200112146799.html

Answer 1

The fact's are that Greenland was about 0.9C warmer in Greenland than it is currently, by direct temperature measurement, according to Dr. Spencer. (Fig. 3), boreholes are a way to directly measure temperature measured in ice (as opposed to proxy data). It seems to be a reasonable conclusion that the Holocene maximum was warmer than the medieval warm period, warmers will generally ignore valid scientific evidence, and present cherry picked proxy data that supports their political agenda.


http://www.weatherquestions.com/Roy-Spencer-on-global-warming.htm

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Answer 2

As Dana says, your graph stops a little short. We're less than a degree away from that warmth. More about the Holocene here:

http://environment.newscientist.com/channel/earth/climate-change/dn11647

But that's not the important thing.

If global warming stops where we are now, the effects won't be too bad. The difficulty is if we get 2-4 degrees warmer. And we're heading there with historical rapidity.

The idea behind most every rational plan to fix global warming is simply to hold down the additional increase to another degree or so, ie to little more than the Holocene Maximum. That is practical, affordable, and will avoid the worst effects. Details:

http://www.spiegel.de/international/world/0,1518,481085,00.html
http://www.ipcc.ch/SPM040507.pdf

And the idea that the Medieval Warm Period was warmer than now, as a worldwide average, is rejected by most all scientists. Proof:

http://environment.newscientist.com/channel/earth/climate-change/dn11644
http://gristmill.grist.org/print/2006/12/13/221054/33?show_comments=no
http://www.globalwarmingart.com/wiki/Image:2000_Year_Temperature_Comparison_png

Answer 3

It is worth noting that the IPCC is not predicting that the entire Greenland or Antarctic ice caps will melt any time soon. Their predictions only go out 100 years, and they are forecasting a sea level rise of less than 1 meter in that time. If Greenland and Antarctica both melted completely it would mean a sea level rise of 68 meters.

Answer 4

The graph in your first link cuts off about 100-150 years ago. The Holocene Maximum was not likely warmer than today.

Answer 5

maybe they are wrong if you check out your lakepowel site they say years are clearly visible wich make no sense beacause what would create a line there would be sediement melting and refreezing so that is a ridiculous coment cause anyones with some knowledge of the north knows it can snow melt snow melt snow melt plenty of times in a year so there counting lines like rings on trees scientist aren't always right kinda like politicians

Answer 6

Actually much of Greenland was farmed during the Medieval Warm Period from 1000-1350. Much more warming has to happen before Greenland gets back to where it was during the MWP.

Read what Reid Bryson says about it:
http://www.wecnmagazine.com/2007issues/may/may07.html#1