Great News from Greenland

Guest essay by Dr. Patrick J. Michaels

I recently returned from a trip to Greenland’s Jokabshavn Glacier, which discharges more ice than any other in the Northern Hemisphere.

Jakobshavn Glacier Image: from NASA

Our route of flight from Reykjavik traversed the ice cap from about fifty miles north of Angmassalik to the airport at Ilulissat, on Disko Bay, about one-third of the way up Greenland’s west coast. In southeastern Greenland, we flew very close to the country’s second-highest peak, Mt. Forel (11,099 feet), and in the near future I will upload a image of a nearby mountain approximately 8,000 feet high completely covered by the ice cap.

It is obvious from the air that there is very little movement over the deepest regions of the ice, and the drift patterns in the lee of some of the submerged peaks are strongly suggestive of at least some regional accumulation. There is virtually no evidence for summer melt in the southeast, while the southwest portion of the ice cap is known to melt and refreeze at the surface on an annual cycle—I saw considerable evidence for multi-year, but small, lakes in that region.

In preparation, I read just about everything I could get my hands on, including a recent very remarkable paper by Dorthe Dahl-Jenson and about 70 coauthors. Dahl-Jensen heads up the Center for Ice and Climate at the University of Copenhagen. Dahl-Jenson’s team drilled to the bottom of the ice in northwestern Greenland, providing us with the first climate history of Greenland that includes the warmest period in the last interglacial period, from about 128,000 to 122,000 years ago, known as the Eemian. That was embedded in the Sangamon Interglacial, which ran from approximately 135,000 to 95,000 years ago.

(For perspective, the last (Wisconsin) glaciation started then and lasted to (nominally) 10,800 years ago—that last date being about a blink of a geologist’s eye ago. Homo sapiens appeared in the ice age, and evidence is that proto-civilization developed while the hemisphere was glaciated.)

One of the reigning myths in climate science is that interglacial temperatures in Greenland were about five degrees (C) above modern, causing a dramatic loss of ice and raising global sea levels about 6 meters (19 feet).  Ice cores from southern Greenland in fact have wood and vegetation at their lowest levels, which are younger than the Eemian.

By measuring the ratio of two isotopes of oxygen (specifically 18O to the much more common 16O) one can infer the air temperature at the time that the snow in each annual layer crystallized.  This technique has been around for decades and is considered quite reliable, and it correlates well with other temperature “proxies” that Dahl-Jensen also used.  Dahl-Jensen found that the average annual temperature peaked at a whopping 8 +/- 4°C (that’s 7 to 22°F!) warmer than the recent millenium in the  ice core during the Eemian maximum.

And still the ice survived. In fact, the top of the ice was only a mere 130 +/- 300 meters “lower” (actually from 557 feet higher to 1411 feet lower) than today. For perspective, her entire ice core was about 8,000 feet in depth.

If, like ex-NASA employee James Hansen, you think that global warming is going to drown us all by melting almost all of Greenland “in a hundred years” (Hansen’s words), perhaps you should try another apocalypse. According to the chart shown in Dahl-Jensen’s paper, the entire 6,000-year period averaged about 6°C warmer than the last 1000 years.

The integrated heating in this region during the Eemian maximum appears therefore to be approximately 36,000 degree-years (temperature change multiplied by time).

Climate models for the future show an annual warming of about 3°C over northwestern Greenland by around 2100, or 300 degree-years. At that rate, it would take 12,000 years to just get rid of about one-eighth of the ice in this core, or about 96,000 years to lose all of it.  (That’s impossible because another ice age will have intervened.)

Evidence suggests that sea levels during the Eemian were about 4-8 meters (13-26 feet) higher than today.

Prior to Dahl-Jensen’s study, it was generally accepted that the vast majority of this rise came from the loss of Greenland’s ice, but now she cautiously writes that:

Although the documentation of ice thickness at one location on the Greenland ice sheet cannot constrain the overall ice-sheet changes during the last interglacial period, the [Eemian core] data can only be reconciled with Greenland ice-sheet simulations that point to a modest contribution (2 m) to the observed 4-8 m Eemian sea level high stand…These findings strongly imply that Antarctica must have contributed significantly to the Eemian sea level rise.

Whew!  Thus does one revolutionary paper shoot pretty much the entire global warming sea-level catastrophe—the one worth being concerned about—through the heart.  Antarctica is so cold that it is projected to gain ice in the coming century, as slightly increased precipitation—which may have recently been detected—falls as more snow, which compacts into more ice.

This puts any sea-level crisis out in the hundreds-of-years realm, at least, and probably far beyond our current era of burning hydrocarbons for energy and heat. In other words, forever.

As for Greenland, I have some bad news about the Jakobshavn Glacier. Its 30 X 6 mile (spectacular) Ilulissat Icefjord is going to be much less spectacular very soon, and I’ll also wager that the quick retreat of the glacier is literally grinding to a halt.

Better go to Ilulissat soon—in the next year or two—to see what was outside my hotel window (live webcam here). The spectacular nature of the fjord is a result of the massive icebergs—some a half-mile wide or so—that break off (calve) from the glacier, float down the fjord for a year or two, and then get stuck in the terminal moraine (laid down during the last glacial maximum, probably from circa 1600, when the Little Ice Age wiped out the Greenland Norse), where the fjord empties out into the ocean.

Unfortunately, the Jakobshavn Glacier has now retreated largely to its grounding line, with the exception of about 20% of the north end of the face—and that part doesn’t have far to go.  In other words, it is largely no longer a calving tidewater glacier, and it is quite obvious from the air that the big bergs are getting much fewer and further between as the glacier moves further onto land. (Don’t forget to buy a helicopter ticket on Air Greenland—it’s worth it!)

When glaciers turn from tidewater to grounded, their recession rates usually slow dramatically (or, in some cases, they stop). This has probably started to happen.

So get your tickets for next summer (or later this summer) now, before the big bergs are gone.

And, before you go, don’t forget to read up—you just might come across some revolutionary good news.

Reference:

Dahl-Jensen, D., et al., 2013.  Eemian interglacial reconstructed from a Greenland folded ice core.  Nature 489, doi: 10.1038/nature11789.

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Mike Bromley the Canucklehead

Just what are those alarmists gonna do with this tale?

🙂
Can’t wait to hear what the CAGW crowd think about this. They won’t like it! Thanks, Patrick, I love a bit of good news in my day.

Chris @NJSnowFan

Nice read Patrick. Thanks…

milodonharlani

No GIS meltdown, no catastrophe, even at six degrees C hotter than now, which isn’t going to happen. Probably not even the picked out of clear air supposedly scary two degrees, at which elevated temperature it would take over 100K years to melt the whole sheet, during which time of course another ice age would be occurring with much lower temperatures.

Excellent post.
Does anyone have a clue what exactly made the Eemian so much warmer than the holocene?

u.k.(us)

It is obvious from the air that there is very little movement over the deepest regions of the ice, and the drift patterns in the lee of some of the submerged peaks are strongly suggestive of at least some regional accumulation. There is virtually no evidence for summer melt in the southeast, while the southwest portion of the ice cap is known to melt and refreeze at the surface on an annual cycle—I saw considerable evidence for multi-year, but small, lakes in that region.
=====================
Dang it,
Your fly-by tells me nothing.
At best a data point.
How would one tell:
…..” there is very little movement over the deepest regions of the ice, and the drift patterns in the lee of some of the submerged peaks are strongly suggestive of at least some regional accumulation.”
==============
You only flew by.
It takes years or decades to make such a determination, for such poorly understood “plastic” flow.
Dang it.

milodonharlani

Michael Palmer says:
July 3, 2013 at 5:30 pm
——————————
Most interglacials have been warmer.
The usual suspects are insolation, orbital mechanics & albedo, but who knows, really?
At SkS, they also try to implicate rapid change in CO2, since the highest absolute concentration was probably less than today’s c. 400 ppmv.

Janice Moore

Re: “… whopping 8 +/- 4°C (that’s 7 to 22°F!) … ”
Is Fahrenheit conversion correct?
4C = 39.2F
8C = 46.4F
12C = 53.6F

Janice Moore

Great article, Dr. Michaels. Thank you for taking the time to report back. It was a refreshing to have a well-informed eyewitness account and, written in such an engaging, enthusiastic, style, it was a pleasure to read.

Janice Moore

It was a refreshing?!! What? I don’t know. It was refreshing. (aarrgh — my proof reading is terrible!)
Glad you made it back safely!

Owen in GA

Janice Moore says:
July 3, 2013 at 6:19 pm
Re: “… whopping 8 +/- 4°C (that’s 7 to 22°F!) … ”
Is Fahrenheit conversion correct?
4C = 39.2F
8C = 46.4F
12C = 53.6F

He is quoting relative temperatures (warmer than current is the exact language) meaning that the current temp is about 15 degrees F.

Lance Wallace

Janice–
I believe he is talking about a difference (“warmer than”) rather than an absolute temperature. Since a Celsius (or Kelvin) degree is 1.8 times as large as Fahrenheit degree, we have
4 C or K degrees = 4*1.8 =7.2 F degrees.
12 C or K degrees = 12*1.8 = 22 F degrees
Interpreting his statement (“8 +/- 4°C (that’s 7 to 22°F!) warmer than the recent millennium”) to apply to the recent global millenium temperature (used to be 15 C but lately I see people are saying it is now 14 C–WUWT?), he is saying the Eemian global temperature was somewhere in the neighborhood of 18 to 26 degrees C. If we have the dreaded 2 C warming by 2100 we will still be 2-10 C cooler than the Eemian.

Arizona CJ

I’m puzzled; where does the wood in the lowest ice core levels come from, if it’s *younger* than the Eemian (the last interglacial)? Especially if Greenalnd didn’t melt in the Eemian?
The Eemian was so warm that you can find Hippopotomus fossiles on the Thames in the UK, so if Greenald did’t melt then, I see no chance of it doing so now.
Thank you for this report. It was a superb read, and does indeed take the air out of the sea level rise hysteria. I think one of the key points is the issue of the Antarctic increase; seems to me that the water for it has to come from somwhere, so I would not be surprised to see the gradual sea level rise of the last few thousand years diminish or reverse.

Luther Wu

Many thanks.
You and Willis could start a travel magazine.

george e. smith

Well in a related matter, the news says that Jason-1 sea level satellite is dead; but is going to remain as space junk for 1,000 years. Why didn’t they think to put a de-orbit system on these things to reduce the clutter? sooner or later, somebody is going to get hurt.
But as to the Greenland glaciers; nice to know there will be ice for all the polar bears hiking over there.
Incidently. , the Jason news said it recorded sea level rise of 1.6 inches (4cm) during its 11 1/2 year life, with an accuracy of “a few cm”; like maybe 4 cm do you think. so maybe zero to 8 cm

Janice Moore

Dear Owen, Dear Lance Wallace,
Thank you, so much! I almost didn’t post that, for I had a feeling I was missing something… . Thanks for telling me what that was! Sorry to interrupt the otherwise high-level science discussion.
Janice

Storm Giant

Thw CBC did a “news” segment about how climate change and global warming (yes they actually said GW) is going to effect agriculture etc. Not one word about record cold winters the past few years.

Michael Palmer says:
July 3, 2013 at 5:30 pm
Does anyone have a clue what exactly made the Eemian so much warmer than the holocene?
============
no carbon tax

Jon

I have problem with these so called temperature readings of old times in ice cores. Since temperature is affected by elevation, how have they figured out what the elevation was when the snow fell many thousand years ago?

philemon

A small mistake in the citation? What I found was this:
NEEM community members
Eemian interglacial reconstructed from a Greenland folded ice core
Nature 493, 489–494 (24 January 2013) doi:10.1038/nature11789

John F. Hultquist

Thanks Dr. Pat – sounds like a fantastic trip and a well written post.
————————————
Janice,
What you did back up there and others have commented on is commonly done. A purist-type technical editor would print things thusly:
a temperature: 15 degrees Fahrenheit becomes 15° F
a temp. change: 15 Fahrenheit degrees becomes 15 F°
Because almost no one does this the distinction has to be inferred.
Another mistake folks make is to use the temperature scales data as though they are ratio data. For example, say it goes to 60 degrees in the afternoon from a low of 30 in the early morning. If you hear someone say the temperature doubled, there’s the error. Play with the numbers a bit. Convert the 30 & 60 from F. to C. and check whether it has doubled. Use the Kelvin temperatures to make such a calculation.
Background: http://www.usablestats.com/lessons/noir

Janice Wrote:
Janice Moore says:
July 3, 2013 at 6:19 pm
Re: “… whopping 8 +/- 4°C (that’s 7 to 22°F!) … ”
Is Fahrenheit conversion correct?
4C = 39.2F
8C = 46.4F
12C = 53.6F
+++++++
This is a common source of confusion. The writer wrote that it was 8 +/- 4C warmer. Or in other words. 4 to 12C degrees warmer. This is NOT the same a temperature of 4C or 12C, but rather 4 additional C (or Kelvin) to 12 additional C warmer. Stay with me here. So you only need to multiply by the scale of 1.8 and not be concerned with the offset because when you subtract the two numbers, the offset goes away. So 4C*1.8 = 7.2 degrees F. 12C*1.8 = 21.6 degrees F warmer.
Try it. If it went from 100C to to 104C, it would be 7.2F warmer. Or to convert everything to F 100C = 212F and 104C = 219.2F. 219.2-212= 7.2,
Mario

Bill Illis

One should not lecture the Greenland ice core scientists about basic math.
They aren’t going to know what you are talking about.
Back on topic, here is a chart of the new NEEM ice core temperatures reaching into the Eemian at 135 Kya versus the previous longest Greenland ice core temperature series as well as Antarctica.
http://s12.postimg.org/9ctilkusd/NGRIP_NEEM_EDC_Global_135kya.png
The wood and vegetation remnants at the bottom of the ice core from the southern third of Greenland was dated to 4 interglacials ago at 400,000 Kya. This interglacial was the longest one since the ice ages started 2.7 Mya although its temperature maximums were only about 1.0C to 2.0C higher than today. Its just that it lasted for 25,000 years and the southern third of Greenland melted out as a result and small trees even grew there. The current interglacial, by contrast, is forecast to last even longer than the interglacial at 400,000 Kya.

kuhnkat

Apparently there is no consideration of the so called SCIENCE of interpreting ice cores being WRONG!!! Keystone Cops staggering from one ridiculous mistake to another.

pat michaels

Comment to U.K. (us)
Motion in ice fields is quite obvious because it creates an uneven surface characterized by waves (similarly to motion in oceans). They are obviously lacking over much of the eastern and central parts of the ice cap on the route lines we flew (100km North of Angmassalik to Ilulissat). When you get further west you can see much more motion, especially as the cap feeds into the icestreams that flow into the Davis Strait.
I hope you will take this phenomenal trip to see for yourself–and before Jokabshavn Glacier completely grounds!
I admit that about 20 minutes into the deep part of the icecap I muttered into the window: “Hansen’s nuts”. The buried mountain kind of says it all, along with Dahl-Jensen.

Chris

> This puts any sea-level crisis out in the hundreds-of-years realm, at least, and probably far beyond our current era of burning hydrocarbons for energy and heat. In other words, _forever_.
Forever is a long time. The normal aging of the Sun will eventually cause it to heat up to the point where all the Earth’s ice will melt and fill the oceans. Then the oceans will evaporate at some point. (This assumes that chaotic orbital behaviour in the outer gas giants doesn’t get us first.)
But this is all a long, _long_ time in the future. I’m not worried… 🙂

george e. smith says:
July 3, 2013 at 7:04 pm
Well in a related matter, the news says that Jason-1 sea level satellite is dead.
the Jason news said it recorded sea level rise of 1.6 inches (4cm) during its 11 1/2 year life, with an accuracy of “a few cm”; like maybe 4 cm do you think. so maybe zero to 8 cm

Hmmm. I wonder if it suddenly died or if they believe the sensors are degraded because they are showing a fall in sea level instead of a rise. Like the ENVISAT data did before that too was declared ‘dead’ well short of its design life.

Richard111

Thank you for posting this. This is broadly covered in John Kehr’s book The Inconvenient Skeptic and explains why current temperatures in Greenland are cooler than the Eemian maximum and the implications of this such that a layman can follow the reasoning.

richard verney

Chris says:
July 3, 2013 at 11:09 pm
////////////////////////
May be sooner than you think. Recently, I watched a programme on the evolution of stars that suggested that within about 1 billion years, save for bacterial life, conditions on planet Earth would not support life as we know it.

tty

Bill Illis says:
The wood and vegetation remnants at the bottom of the ice core from the southern third of Greenland was dated to 4 interglacials ago at 400,000 Kya.
Actually no. If you go back to the original publication it actually says probably 400.000 to 1 million years old. This has since morphed to 400.000 years in CAGW circles since this makes it (barely) possible to place it in MIS 11 which was astronomically a close match to the current interglacial.
By the way small trees grow in Southern Greenland today too.

Very nice story about the Greenland ice sheet by Dr. Michaels!
My wife and I made a trip to Greenland in 2000:
http://www.ferdinand-engelbeen.be/familie/greenland.html
Indeed, spectacular view of the Ilulisat ice fjord and other parts of Greenland, especially from the air.
The current high melt is not higher than what happened in the 1930’s and the current summer temperatures are not higher than in the previous warm period. See:
http://www.ferdinand-engelbeen.be/klimaat/greenland_temp.html
The breakup point did already retreat since (before) 1850:
http://www.ferdinand-engelbeen.be/klimaat/greenland_glacier.html
Inbetween the warm periods, the glacier advanced again. As in average there is warming since at least back to 1850, the breakup point of the floating part retracted and now is about on land. As the resistance of the downhill ice now is reduced, the ice flow increased over time and now goes far inland. That happened in the 1940-1950’s too:
http://www.agu.org/meetings/fm05/fm05-sessions/fm05_C41A.html (last paragraph).
The warm/cool periods in Greenland may be related to the NAO and mostly are opposite to what happens in NW Europe…
The Eemian indeed was a lot warmer than today with maximum CO2 levels around 290 ppmv:
http://www.ferdinand-engelbeen.be/klimaat/eemian.html
Thus the current melt and temperatures are far from unprecedented, even with much lower CO2 levels…

JM VanWinkle

Bill Illis says:
July 3, 2013 at 9:49 pm
“The current interglacial, by contrast, is forecast to last even longer than the interglacial at 400,000 Kya.”
Models for interglacial terminations vary considerably. Perhaps you have a citation for your model. From what I have read, obliquity strongly dominates over precession, and that the interglacial period favored by obliquity would dictate what has been seen geologically, namely we are at the end of the Holocene. Newer models that project an extended Holocene also assume CO2 has a large impact and we know those CO2-temperature models make rash assumptions. One more thing, beliefs in ocean circulation changes during glaciation were found to be in error as they were based on just one sediment core location. After 26 more cores were included in the ocean circulation, it was found that ocean circulation changes very little between interglacial and glacial periods. That throws cold water on looking at ocean circulation as a glaciation proxy.
Look, i am not trying to be argumentative here, If you think you have a good model for the Holocene duration, in a paper that is not paywalled, I would be interested in its key assumptions. Thanks.

Jon says:
July 3, 2013 at 8:25 pm
I have problem with these so called temperature readings of old times in ice cores. Since temperature is affected by elevation, how have they figured out what the elevation was when the snow fell many thousand years ago?
While the temperature at the summit is reproduced from borehole temperatures, the Greenland and Antarctic temperature reconstructions are done by looking at the oxygen and hydrogen (deuterium) isotope changes. The isotope composition of water vapour changes with temperature at the surface on evaporation. Heavier isotopes relative increase with higher temperatures. The same happens when water vapour condenses to water and/or ice/snow. Thus the isotope composition in the ice layers shows the temperatures of the NW Atlantic Ocean for Greenland, where most of the Greenland ice cap originates, the nearby Southern Ocean for coastal Antarctic ice cores and most of the SH oceans for the inland Antarctic ice cores. But they all need to be corrected for any changes in temperature in the condensing zones. The latter gives an error range and still is under much discussion, but the general trends are quite real.

Christopher Hanley

“… Dahl-Jensen found that the average annual temperature peaked at a whopping 8 +/- 4°C (that’s 7 to 22°F!) warmer than the recent millennium in the  ice core during the Eemian maximum …”
.
I’m sorry but the model says no:
“… Kaspar et al. (GRL, 2005) perform a comparison of a coupled general circulation model (GCM) with reconstructed Eemian temperatures for Europe. Central Europe (north of the Alps) was found to be 1–2 °C warmer than present; south of the Alps, conditions were 1–2 °C cooler than today. The model (generated using observed GHG concentrations and Eemian orbital parameters) generally reproduces these observations, and hence they conclude that these factors are enough to explain the Eemian temperatures …” (Wiki).
/sarc.

JM VanWinkle

Bill Illis,” Its just that it lasted for 25,000 years”
Do you have a temperature graph for this with link? The one I have only shows a peak of about 15,000 years.

From a rather strange article at http://weather.yahoo.com/strange-eats-scientists-snack-research-125943362.html:
“Climate scientists who pull up ice cores stretching back 100,000 years regularly plunk broken core pieces into their drinks. The cubes fizz like soda as they melt, because of compressed gas bubbles trapped in the buried ice. “I actually made drinking glasses out of 40,000-year-old ice by hollowing out the inside of a waste core, a byproduct of the sampling we did,” said Ed Brook, a professor of geosciences at Oregon State University.
As long as researchers are careful to avoid sections of ice laid down during years of nuclear testing, the oldest ice on Earth is pretty fresh and pure; it has lost its impurities through pressure squeezing.”
I find the last phrase in this quote rather curious, in the context of the ice core chemical composition reliability.

Someone isn’t being tidy with the script. This story says ENVISAT is still alive…
http://notrickszone.com/2013/07/04/jason-1-topex-satellites-for-measuring-sea-level-now-both-decommissioned/

phlogiston

Bill Illis says:
July 3, 2013 at 9:49 pm
One should not lecture the Greenland ice core scientists about basic math.
They aren’t going to know what you are talking about.
Back on topic, here is a chart of the new NEEM ice core temperatures reaching into the Eemian at 135 Kya versus the previous longest Greenland ice core temperature series as well as Antarctica.
http://s12.postimg.org/9ctilkusd/NGRIP_NEEM_EDC_Global_135kya.png
The wood and vegetation remnants at the bottom of the ice core from the southern third of Greenland was dated to 4 interglacials ago at 400,000 Kya. This interglacial was the longest one since the ice ages started 2.7 Mya although its temperature maximums were only about 1.0C to 2.0C higher than today. Its just that it lasted for 25,000 years and the southern third of Greenland melted out as a result and small trees even grew there. The current interglacial, by contrast, is forecast to last even longer than the interglacial at 400,000 Kya.

Are the interglacials which happen at nodes of minimum oscillation amplitude of both eccentricity and the precession index, both longer and cooler than other interglacials? This would relate to the current interglacial and those 400k and 800k years ago.
On the other hand it looks like maxima in the amplitude of the precession index oscillations destabilize the interglacials, i.e. at 200k and 600k years ago – these interglacials are double-headed and cooler.

johnmarshall

Jon wonders how temperature can be calculated from O18/16 data.
The water vapour is from sea level and transported in clouds to fall wherever. So mountain top snow will tell sea level temperatures from the O18/16 ratios. This gives very accurate data.

Snowlover123

Of course, the models have overestimated the rate of warming, thus, it would take even longer than 96,000 years, assuming the warming rate continues in the future.

Mike McMillan

Here are a couple shots I took about five years ago, east coast of Greenland, looking due west. The ice has to go over a cliff to get down to the Atlantic. Even if the icecap melts, much of it won’t be adding to sea level, just making a lot of inland lakes.
http://www.rockyhigh66.org/stuff/greenland/Greenland0109a.jpg
Google Earth: 60.718805° -43.837385°
http://www.rockyhigh66.org/stuff/greenland/Greenland0108a.jpg
60.841478° -43.741298°

Ed Zuiderwijk

Interesting pice, apart from a line that should read:
130 +/- 300 meters “lower” (actually from about 550 feet higher to 1400 feet lower)
The redundant “accuracy” of the 557 and 1411 really is any eyesore.

For those interested, here is a different view of ice breaking from the end of a glazier at the bottom of Argentina, the show is the “The Arrows of Time”. You can hear the great cracking sounds and huge slabs of ice dropping into the lake.

Mike Ramsey

Michael Palmer asks, “Does anyone have a clue what exactly made the Eemian so much warmer than the holocene?”
A fuller answer can be found here
The author gives three reasons:
Changes in solar insolation, which is a measure of solar radiation energy received on a given surface area in a given time commonly expressed as average irradiance in watts per square meter (W/m2).
Changes in the concentrations of greenhouse gasses in the atmosphere.
Changes in the albedo of the Earth, which is a measure of how much energy from the Sun is absorbed due to changes in reflectivity of the Earth’s surface, such as from changes in snow and ice cover.
I would add a fourth possibility, increased heat flow from the earth’s interior.

Gary Pearse

Good to see a growing real climate (the generic kind, not RC) science literature – almost every day new papers telling us we were bamboozled by green hype. I note that it is still pretty much frozen over most of the Greenland ice sheet and the Canadian Arctic archipelago:
http://www.esrl.noaa.gov/psd/map/images/fnl/sfctmp_01.fnl.html
and that north of 80 has been below average temp for the last few months:
http://ocean.dmi.dk/arctic/meant80n.uk.php
As Willis Eschenbach has pointed out a few times, one of his regrets is the ironic collateral damage to real environmentalism by green activists/politicians. Like most thoughtful skeptics in this struggle, I too want a clean, healthy environment, clean water and, yes clean affordable energy for all. The “clean” part has been totally abandoned for the vilifying of our precious and productive CO2 levels. I had been hoping that by now, we would have had a few Atlantic salmon return to the Ottawa River and other rivers abandoned by this fish throughout Ontario and Quebec. Also, as a young scientist/engineer working in Africa in 1960s, I had thought that in my lifetime, with newly acquired independence and a treasure trove of resources, this continent would be joining us in health and prosperity. This possibility, too, was even greater a collateral damage (purposeful malice, rather?) commited by people I had thought had their best interests at heart. Either this elitist bunch and their institutions must collapse or competing institutions created (a bank to give Africans reliable cheap electric power for example – they could then do the rest handily by themselves).

Jonathan Grove

I’d like to see the evidence for the survival of the Greenland Norse to c. 1600.
That’s nearly a century later than most current estimates.

Bill Illis

JM VanWinkle says:
July 4, 2013 at 12:50 am
July 4, 2013 at 01:16 am
———————————–
Here are six different global temperature estimates for the interglacial at 400,000 years ago [Antarctica Epica DomeC, Lisiecki-Raymo (04), Lisiecki-Raymo (09), Zachos (05), and Lawrence (10)]. One can get anything from 18,000 to 30,000 years for how long that interglacial lasted.
http://s14.postimg.org/5yll4hpn5/400_Kya_Interglacial_Global_Temps.png
Regarding how long the current interglacial will last, here are two zoom-in charts of June solar insolation at 65N (from Berger and Loutre 91). This value needs to drop below 470 W/m2 to kick us into an ice age going by paleoclimate history. It drops very, very marginally in the next 1500 years and then goes back up again. After that, we don’t get close to the trigger point until 52,000 years from now but more likely 125,000 years from now. This will be the longest interglacial by quite a margin since the ice ages started. The Milankovitch Cycles are not as regular as people think.
http://3.bp.blogspot.com/_nOY5jaKJXHM/S0pMeoX0DYI/AAAAAAAAAl8/ficHeOA8Jdw/s1600-h/insolation+10k.jpg
http://2.bp.blogspot.com/_nOY5jaKJXHM/S0pMWh0jC_I/AAAAAAAAAl0/jFrzGsHsWEE/s1600-h/insolation+200k.jpg
http://www.dvfu.ru/meteo/library/243887.pdf

pat michaels

Gary Pearse
Don’t know why my comment didn’t post–I’ll repeat.
We took an unusual deviation to the north on the flight from Reykjavik back to Dulles and flew the length of Labrador after crossing the Davis Strait–which had the largest iceberg field that was remote from any pack thatI have ever seen. At any rate, there was partial snow cover all the way down to where the roads begin, which would be around Churchill Falls, at latitude 53. Date was June 26. Amazing.

michaelspj

Ferdinand–
We actually wrote a paper on historical Greenland melt and of course the climategate goons called for the head of the editor for merely publishing it.
http://onlinelibrary.wiley.com/doi/10.1029/2010JD014918/abstract
Indeed there was probably higher ice loss in the 20s and 30s.
PJM

Lightrain

Yabut, the glacier IS retreating!
“the Jakobshavn Glacier has now retreated largely to its grounding line”