Green Myth-Busting: Greenland was Once Green
Greenland MYTH: When Eric the Red and his Viking buddies settled Greenland, it was a lush pastoral paradise fit for farming and raising animals.
Facts: As climate change skepticism has developed into a full-blown industry, a number of myths have filtered out about historical patterns of warming and cooling: just mention the “Little Ice Age” or the “Medieval Warm Period” to your favorite skeptic, and let ‘em go…
As a history buff, I always found today’s myth fascinating. As Coby Beck at Grist notes, Viking leader Eric the Red gave Greenland its name not because it was lush and green, but because he wanted folks back home to think it was:
Greenland was called Greenland by Erik the Red (was he red?), who was in exile and wanted to attract people to a new colony. He thought you should give a land a good name so people would want to go there! It likely was a bit warmer when he landed for the first time than it was when the last settlers starved due to a number of factors — climate change, or at least some bad weather, a major one.
But it was never lush, and their existence was always harsh and meager, especially due to the Viking’s disdain for other peoples and ways of living. They attempted to live a European lifestyle in an arctic climate, side by side with Inuit who easily outlasted them. They starved surrounded by oceans and yet never ate fish! (Note: this was not a typical European behavior, and is a bit of a mystery to this day.)
The issue here, of course, really isn’t Greenland’s name; it’s the idea of a Medieval Warm Period that skeptics claim was comparable to the present day in terms of the average temperature (or even warmer!). By extension, ice melts on Greenland aren’t that big a deal: it’s happened before.
Coby has thoughts on the Medieval Warm Period, and points to information from NOAA. RealClimate, the blog for anyone interested in hardcore climate science, also presents a number of reasons why the perception skeptics have about the Medieval Warm Period are likely incorrect.
Greenland wasn’t green in the tenth century… and we don’t want it to become green this century…
December 10th, 2007 at 8:03 pm
Hi Jason,
Your concession looks like it was worded by a lawyer, but it does agree with my statement that IPCC ignored (or rejected) the conclusions of a published report that directly contradicted its claim of net mass loss of GIS 1993-2003, so it works for me.
Now that our Greenland discussion is concluded, let’s re-activate our discussion on Antarctica, and see if we can move a little more quickly than we did on Greenland.
In doing so, let’s not repeat your earlier waffling that covered both Greenland and Antarctica:
· Your October 28, 3:50am: Wingham report came out too late, i.e. after WGI expert peer review, and was ignored for this reason
· Your October 31, 12:57pm: IPCC would have had no reason to ignore research; besides the total mass gain is considered to be short term and will turn to the negative
· Your October 31, 4:09pm: Wingham report came out too late; IPCC has a six-year process that cannot be halted at the last minute
· Your November 6, 12:54pm: I was wrong about report coming out too late but there are other reports out there as well
· Your November 8, 10:59pm: IPCC examined Wingham plus other papers before arriving at a conclusion
The statements below are taken from my blogs to you of 14 and 29 November.
The report I cited (Wingham et al.) covered 72% of the surface of Antarctica, excluding 6% for steeply sloping coastal areas and 22% near the pole outside the range of satellites.
The study, based on actual measurements by satellite altimetry, reported a net mass gain over the period (1993-2003) of 27 Gt/year, which they equated with a sea level lowering of 0.08 mm/year.
IPCC claimed a net contribution to sea level rise of 0.21 mm/year from mass loss over the same period.
This corresponds to a net mass loss of 71 GT/year, as compared to a net mass gain of 27 Gt/year over the same period, as reported in the Wingham study.
Based on the above information, I made the statement that IPCC ignored published data that directly refuted its claim of Antarctic mass loss over the period 1993-2003.
The Wingham study for Antarctica went a bit further than the Johannessen study for Greenland, in that it calculated a mass balance for the entire Antarctic ice sheet, including estimates for the sections that could not be measured by surface altimetry. Below are some pertinent quotes from this study:
Method and time span:
“We analyzed 120 million European remote sensing (ERS) satellite altimeter echoes to determine the changes in volume of the Antarctic ice sheet from 1992 to 2003.”
Scope:
“Our survey includes 72% of the grounded ice sheet (8.5 million sq. km.), omitting just 6% of coastal sectors (0.8 million sq. km.) where data are lost due to steep slopes, and 22% of the interior (2.6 million sq. km.), which lies beyond the latitudinal limit (81.6ºS) of the satellite ground track.”
Result and calculated impact on sea level:
“We show that 72% of the Antarctic ice sheet is gaining 27±29 Gt/year, a sink of ocean mass sufficient to lower global sea levels by 0.08 mm/yr.” [author’s italics]
Estimate for unsurveyed areas:
“Our estimate of the mass gain of the unsurveyed Antarctic interior is comparable to our estimate of the mass loss of the unsurveyed coast.”
N.B. The gains in the interior were converted to mass as snow pack, with a density of 0.35 and the losses in the marginal coastal area were converted as ice, with a density of 0.917.
To summarize, the Wingham study concluded that the Antarctic ice sheet gained mass (+27 Gt/year), equivalent to a sea level lowering of 0.08 mm/year over the study period (1992-2003).
This is the conclusion that IPCC ignored (or rejected) in making its claim in 2007 SPM of a net mass loss contributing to a sea level rise of 0.21 mm/year (-71 Gt/year) over this same period.
Please show me that IPCC did not ignore or reject (i.e. not accept as correct) the conclusion of a net overall ice gain in Antarctica (1993-2003) from the Wingham study when they made their claim of a net overall ice loss in Antarctica over the same period, or concede that you have lost this point in our debate, so we can move on to the next point.
Regards,
Max
December 10th, 2007 at 9:42 pm
Max,
My concession was carefully worded for a reason. It does not at all agree with your statement that the IPCC “ignored” published research. I was hoping that you would pick up on this, but apparently you did not. I’ve tried to explain this to you before, but you dismissed the argument as irrelevant. What you think you have proven and what you have proven are two completely different things. You have proven that the IPCC report differs from a particular study. What you insist that I concede to is that the IPCC “ignored” or “refused to take notice of” the study in question, which adds a willful intent into the equation. It is this added intent that is the difference between the two (what you have proven and what you think you have proven), and for which you have, as of yet, failed to provide any evidence. In order to receive a concession from me that is equal to the concession that you have requested, you must provide some proof to support your argument. Do you understand this difference, Max?
December 10th, 2007 at 10:10 pm
Hi Jason,
Let’s not go back to Greenland. “Willful intent” on the part of IPCC was not part of my argument, nor do I claim it now.
Regards,
Max
December 11th, 2007 at 1:40 am
Hi Jason,
To your concession December 10, 7:27pm and follow-up post of 9:42pm.
You conceded. I accepted. But you still want to qualify your concession “ex post facto”, by inserting a totally new concept of “willful intent”, which I pointed out to you was never part of my argument.
Why make things complicated when, in fact, they are simple?
1. Report concludes “A”
2. IPCC claims direct opposite of “A”
3. Therefore, IPCC does not accept conclusion of report (“A”) as truthful or correct.
Are you still with me, Jason?
To “not accept” a report, one either has to (a) be unaware of its existence, (b) find obvious errors in the methods used in the report which render its conclusions meaningless, (c) come up with a more convincing or more comprehensive later report that covers the same period and scope which clearly demonstrates to the author of the first report that the conclusion reached in his report was in error, so that he sees his error and retracts this conclusion, which is then superceded by a new conclusion, thereby removing his previously reported conclusion from the record or (d) one has to ignore or reject it (whether this is “willfully”, through inadvertent action, inability to grasp or recognize its significance, negligence or for whatever reason, is not germane to our discussion, and I really do not want to go there).
You showed me: (a) that IPCC was indeed aware of the report but you were not able to show me that (b) there were obvious errors in the methods used in the report which render its conclusions meaningless or that (c) there was a “more convincing or more comprehensive later report covering the same time period and scope, which clearly demonstrates to the author of the first report that the conclusion reached in his report was in error, so that he sees his error and retracts this conclusion, which is then superceded by a new conclusion, thereby removing his previously reported conclusion from the record”. So we are left with (d).
I certainly have not and do not now claim any “willful intent” on the part of the IPCC. OK?
Hey, Jason, I accepted your concession as you wrote it, so why keep rehashing this issue?
Come on, Jason. It’s time to discuss Antarctica.
Regards,
Max
December 11th, 2007 at 8:44 am
(1) Hi Max, RE recent Reasic stuff.
It is obvious, not just of now, but historically, that Reasic (and also the ‘motie) will NEVER concede anything of significance if it offends “THE FAITH”, (to which BTW Reasic admitted baptism and “become-expert-missionary”, from just a mere year-and-a-bit ago!
Initially I found the debate starting for me back in May very entertaining, thinking that independent observers might see the shallowness of Reasic’s and ‘motie’s wanderings. However, the public exposure to this debate has since been excised, and I’m becoming ever more irritated that Reasic spiels whatever he likes in a secure comfort that;
a) It is extremely unlikely that any rational potential visitor to our thread can ever find this blog.
b) For example, if someone does “Search for Greenland”, (internal Google), and then fortuitously clicks Vikings, they may get close, but might actually be looking for different stuff on the MWP. If they then start from page 1, they will be rapidly bewildered because the first ~200 posts cover many other topics and are all out of sensible sequence. (Because of the “Platform Change”) They would need to go to page 46, and then back to about page 26, to be able to pick-up this more recent unending and rather DIFFERENT topic of GIS .
c) The next problem is; even if they were interested in GIS, how could they stay awake long enough grinding through Reasic’s endless waffle, where he changes tack or simply ignores important questions. It’s a big ask for any rational visitor ploughing through some twenty website pages!
d) Moreover, if from hereon the debate does change to ANTARCTICA, Reasic will have the self righteous comfort that he is LEADING 2 : 0 in this “debate”. (This IS totally a valid conclusion for HIM based on HIS dogmatic FAITH)
e) If potential visitors subsequently search for ANTARCTICA, it will be a long while before the word-count on Antarctica in this here GREENLAND blog pulls it up the echelon in the Google hit-list, where they MIGHT find it, with appropriate skill or luck.
So what’s the point?
Some 250 plus posts ago, Reasic, a credited site author, whom apparently has some credibility with the chief editor, (Jeff M-S) agreed that it would be a GOOD IDEA to untangle the mess that we had WAY-BACK-THEN, and initiate a sensible clean blog, accessible to ALL potential visitors.
The explanation why this did NOT happen may perhaps be found in a) through e), above!
Max, how about you and me refuse to debate Antarctica on this phlegm?
We should insist that Reasic expose the debate to “the people” out there, with a Jeff McIntyre-Strasburg RECOMMENDED Journal.
>>>>>>>>>>>>>><
(2) Hi Reasic,
PLEASE DO THE PROPER THING, and raise a new Journal on ANTARCTICA, and don’t tuck it away where it can’t be found by “people of the world”.
I suggest you introduce it with words something similar to one of your earlier Blog-Journals:
I [Reasic] had an interesting question from Max…. (which we should discuss)…..and then quote Max’s recent compelling summary.
Then you guys can go hammer and tongs on Antarctica, with the prospect of visitors taking-it-all-in. (They need not contribute, as long as they read and digest what is discussed!)
>
(3) Reasic, I anticipate me being not much involved from hereon, unless you raise a sensible Journal, and/or unless maybe you can answer a question raised severally of you before: Do you believe that the Grand Canyon was the consequence of “The Flood” as described in “THE BOOK” and religiously dated to ~4000 years ago? If you answer NO, perhaps I could then become more interested in talking with you!
I have a painful experience with a fundamentalist Christadelphian sect and it may help me to understand where you are coming from if you truthfully answer that question immediately above.
Cheers, Black Wallaby
BTW, Reasic, I note that there is no response from you on some important questions that I raised far above. Should I recapitulate them?
December 11th, 2007 at 1:37 pm
No, I do not, Bob.
December 11th, 2007 at 2:36 pm
Max,
I have a couple of responses for you:
Actually, Max, I did explain to you that there were several potential explanations for the Zwally findings. However, in your desparate attempts to cling to this particular study that you happen to agree with, you have consistently ignored my arguments. I will reiterate those points for you here, so that you can see them one more time:
1. The Zwally study extended ERS data into the marginal areas, where Johannessen considered it to be unreliable, to cover an additional 10% or so of the GIS.
2. The Zwally study only worked with ATM data from 1993 to 1999, which means it is missing a full four years of data. This is crucial because not only is the missing data in the marginal areas where the most pronounced ablation has occurred, but it is also in the latter portion of the time period, where ablation increased.
3. The Zwally study did not cover the entire GIS. It claimed to cover the entire COTERMINOUS ice sheet, which leaves out an estimated 5% of the GIS in the outer areas.
I have previously pointed these out to you, because they could potentially explain the differences between the results of this study and others (i.e., Thomas), but you have continually ignored these points.
Now, I must also clarify something else. This is not necessarily an attempt to point out “obvious errors”, as it is to simply understand potential reasons for differences and find the true solution. In your next statement (or option), you demonstrate that you don’t understand how this process works:
You seem to think that the solution to the fact that there are multiple conflicting studies is only one of them can be correct. It is true that there can only be one correct number for the mass balance of the GIS over a particular time period, but this number is not necessarily going to be found squarely in line with any one study. There must be some effort to figure out the reasons for the papers’ differences and determine the true value. This is exactly what the IPCC did. They examined the data and methods of ALL of the available research on the subject, and arrived at a conclusion that is not in line with any one study. Your insistence that there be one immaculate study, and that the Zwally study is that flawless research that the IPCC obviously “ignored” is completely and totally irrational. As much as you would love to label me a believer in the IPCC, as though it were a religion, you have also shown a religious zeal for the idea that the IPCC is nefarious.
This is a strange contradiction to your previous comment about the intentions on the part of the IPCC. On page 45, you said the following:
This certainly sets up a scenario in which the IPCC has intentionally done one thing, and then attempts to trick people into thinking they did something else. There is nothing unintentional about it. And yet, now, you want me to believe that intention is not at all a part of your argument by saying:
Actually this is extremely important, and so we must certainly go there. Your use of weasel words in this debate has been extremely funny. It is so plainly obvious what you initially meant when you claimed that the IPCC “ignored” published data, and yet now you want to re-define the word and make it sound as though you don’t believe in a massive conspiracy. If you truly intend to include the possibility that the IPCC was unable “to grasp or recognize [a certain study's] significance”, then “ignore” might not be the word that you would want to use. So, I think it might be fitting for you to re-word your own argument to clarify your real meaning. This is why I only conceded to the fact that the IPCC’s report differs from the Zwally study, which is completely reasonable and explicable via an understanding of ALL of the research that is available.
I know this is long, and you have a hard time with long posts, but please respond to these main points:
1. I have indeed proven to you that there are several reasons why the Zwally study might be more conservative in its estimate of mass balance for the GIS.
2. Your entire approach to this subject is wrong. You seem to be treating each study as inseparable wholes, only one of which can possibly be correct. Instead, you need to understand that the data and methods of each study can and should be examined in an effort to determine the truth, which will most likely not be in line with any particular study.
December 11th, 2007 at 6:00 pm
Max and Bob,
FYI: I contacted Dr. Thomas for some clarification on the differences between bis study and the Zwally study, and the following was his response:
Max, the first paragraph should help to answer your response about density changes from earlier:
Actually, the truth is that Thomas did also apply this correction. However, correcting for a decrease in elevation due to compaction is a separate issue from the assumed density of the initial increase at higher elevations. Zwally used that of ice, while Thomas used a fairly conservative 600 kg/m^3. I wanted to wait until I received a response on this before I added to the list above, so now that I have it, this would make number four on my list of problems with the Zwally paper.
December 11th, 2007 at 8:15 pm
Hi Jason,
Thanks for your post.
You wrote: “As much as you would love to label me a believer in the IPCC, as though it were a religion, you have also shown a religious zeal for the idea that the IPCC is nefarious.” Big word, Jason, but untrue and unfounded.
I am just a rational skeptic that does not automatically believe everything that is served up as “absolute truth” without first examining it rationally and skeptically, particularly in this case, where multi-billion dollar research grants are at stake to provide the scientific justification for a political agenda involving hundreds of billions of dollars being shuffled around by bureaucrats, politicians, carbon credit hedge funds, etc. It is my belief that “big bucks” can corrupt, so that when “big bucks” are at stake (as is the case here), more rational skepticism and examination of claims is warranted than when this is not the case. So this shoots down your “religious zeal” postulation. Got where I’m coming from on this, Jason? Please confirm that you understand.
You wrote: “Yes, Jason, I am “saying that the IPCC is trying to fool everyone into thinking that they actually considered these studies and their findings, but they really didn’t”, because THAT IS WHAT THEY DID.”
I never saw anywhere in the SPM that IPCC even mentioned Johannessen/Zwally (maybe it is in the footnotes or backup). YOU were the one who brought up this whole statement, but I agree that what I should have said (since I may have a suspicion but have no real proof why IPCC does anything that it does):
“JASON is trying to fool (or bamboozle) MAX into thinking that ‘IPCC actually accepted (i.e. did not reject or ignore) these studies and their findings, but they really didn’t’, because that is what Jason did and is continuing to do.” This statement would EXACTLY reflect my opinion here. OK?
You wrote: “I have indeed proven to you that there are several reasons why the Zwally study might be more conservative in its estimate of mass balance for the GIS.”
Yes, Jason, you brought one reason (the fact that ATM results did not cover the whole period, while ERS results did); I do not recall that you brought “several reasons”. Please be more specific.
On the other hand, I have shown you why the Zwally report might actually have understated the net mass gain 1992-2003, by truncating a six-month colder season between October 2002 and April 2003 from Johannessen’s record. This period is mentioned by Hanna et al in his statement: “Recent high snow accumulation events occurred in winter 2004/05, concentrated in west Greenland (Nghiem et al. 2007), and winter-spring 2002/03 in SE Greenland (Krabill et al. 2004; Box et al. 2005; Hanna et al. 2006).” This is the “high snow accumulation event” that Zwally truncated from the Johannessen ERS record. Had he not truncated the record and had he thereby included all this extra snow, the gain in GIS mass would quite obviously have been HIGHER than what Zwally reported, right? Pretty logical to me, Jason.
Yes, Jason, I have also shown you why the ICESat/ATM results 1994-2004 do in fact underestimate by a factor of five the massive gains in the vast interior found by Johannessen from more comprehensive ERS results, thereby exaggerating a negative mass balance. So what?
This is “ho-hum” talk, though, Jason, because it just confirms my point that IPCC rejected the Johannessen/Zwally reports in favor of others.
I pointed out to you that of ALL the reports you cited ONLY the Johannessen and Zwally reports COVER THE ENTIRE TIME PERIOD as the IPCC claim, with the exception (which I pointed out above) that Zwally truncated Johannessen’s study by 6 months. I will recapitulate, since you apparently missed the point:
Johannessen covers 1992-2003 with tens of millions of data points from ERS altimetry; shows massive “increase of 6.4 cm per year in the vast interior >1500 meters, in contrast to previous reports of high-elevation balance”, concludes a net growth of 5.4 cm per year over entire study area.
Zwally covers 1992-2002 (see note above); confirms and extends Johannessen finding based on ERS altimetry plus added ATM results, concludes an overall gain in ice mass of 11 Gt/a, despite truncating the “high snow accumulation event in winter-spring 2002/03” from Johannessen record, so is very likely showing an UNDERSTATED mass gain, rather than an exaggerated one, as you claim above.
Krabill et al. (ATM), cover parts of 1994 and 1999 concludes “ice sheet in balance on average >2000m” and resulting “51 cubic km/year loss from the entire sheet” (pre-Johannessen stuff that still concludes “high-elevation balance”, which the more comprehensive Johannessen study later showed to be incorrect)
Velicogna and Wahr covers 2000-2004 (GRACE stuff outside our time frame)
Another Velicogna and Wahr covers 2002-2006 (more GRACE stuff outside our time frame)
Rignot et al. covers pieces of 1996, 2000, 2005 (“spot” mass-budget calculations covering parts of some years, only two of which are within our time frame)
Ramillien et al. covers 2000-2005 (more GRACE stuff outside our time frame)
Chen et al. covers 2002-2005 (more GRACE stuff outside our time frame)
Luthke at al covers 2003-2005 (more GRACE stuff outside our time frame)
The ONLY TWO STUDIES THAT COVER THE ENTIRE TIME PERIOD which we are talking about are the reports of Johannessen and Zwally.
These are also the ONLY TWO STUDIES that cover a time span of 10 years or more, rather than some shorter period, and therefore are less likely to have results that are distorted by year-to-year variability. To quote Hanna, Box et al. “Most of the observational studies have data spans of less than a decade, which also means that the interpretation of their results may be seriously affected by large year-to-year variability in GIS mass turnover, i.e. sudden glacier accelerations.”
Yet THE ONLY TWO STUDIES that covered data spans of more than a decade and showed net growth of the GIS are EXACTLY the two which IPCC chose not to accept as evidence for a Greenland ice sheet that is gaining mass, when it made its claim of net GIS ice loss OVER THIS SAME TIME PERIOD.
You conceded. I accepted. Yet you are unable to let this dead horse lie, and keep bringing more and more obtuse arguments to retract the concession you just made less than two days ago, which I immediately accepted! How weird.
Drop it, Jason. Your arguments are tired. I have heard them all before. You have been unable to bring EVIDENCE that refutes my statement that “IPCC ignored (or refused to accept, if you prefer) published reports that directly contradicted its claim of ice loss in the GIS equivalent to a sea level rise of 0.21 mm/year over the period 1993-2003”, whereas I have brought you the evidence that this is exactly the case.
Antarctica, Jason.
Regards,
Max
PS As an interesting sideline relative to your discussion with Black Wallaby on Greenland temperature history, the Hanna et al. report states in its summary:
“Recent relatively high summer temperatures (1995-2005) are associated with increased net ice loss over Greenland. Recent warm events are about the same magnitude, if not smaller, than those of the early 20th century warm period (1918-1947). 2006 was not as warm as other recent years such as 2003 or 2005. Physical response mechanisms, such as hydraulic acceleration of the ice sheet from continued warming, remain incompletely understood.”
December 11th, 2007 at 9:38 pm
Hi Jason,
Thanks for long post that apparently crossed with my answer to your last long post.
I am going to concentrate on your last argumentation, which you have asked me to address, since we have rehashed most of the other stuff ad nauseum.
You wrote:
“I know this is long, and you have a hard time with long posts, but please respond to these main points:
1. I have indeed proven to you that there are several reasons why the Zwally study might be more conservative in its estimate of mass balance for the GIS.
2.Your entire approach to this subject is wrong. You seem to be treating each study as inseparable wholes, only one of which can possibly be correct. Instead, you need to understand that the data and methods of each study can and should be examined in an effort to determine the truth, which will most likely not be in line with any particular study.”
To your first point:
And I have indeed proven to you that there is a reason why the Zwally study might understate the net mass gain of the GIS, since it truncated the period between October 2002 and April 2003, which has been described as a period of “high snow accumulation” (i.e. high mass gain). So we have a wash here, Jason. Leaving winter out of a study on annual snowfall will certainly cause a somewhat “skewed” result, right?
To your second point:
I have shown you that only the Johannessen and Zwally reports cover a period of study with results that span over 10 years.
I have shown you that this period is the same period as the IPCC claim.
I have shown you that all the other studies either lie outside this period or show study results that cover shorter time spans within this period.
I have brought you a statement (Hanna et al.) saying that “Most of the observational studies have data spans of less than a decade, which also means that the interpretation of their results may be seriously affected by year-to-year variability in GIS mass turnover, e.g. sudden glacier accelerations.”
And I have shown you that IPCC did not accept the results of the only two studies that covered the entire time frame of their claim of net mass loss, since these results directly contradicted their claim.
In other words: IPCC ignored (or “rejected” or “refused to accept”, if you prefer) published reports that contradicted its claim of net loss of the Greenland Ice Sheet equivalent to a sea level rise of 0.21 mm/year over the period 1993-2003.
You have been very astute in pointing out WHY (in your opinion) IPCC chose to do this, which may all probably be very pertinent. But the basic fact remains that this is what they did.
I never claimed they failed to accept the results of ALL reports or, even less, of those that supported their claim. I said they failed to accept the results of those two reports that contradicted their claim, because that is exactly what they did.
Regards,
Max