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 6th, 2007 at 12:24 am
Hi Jason,
You wrote: “I know you are not claiming that the IPCC has ignored ALL research, but whenever I point out to you that the Johannessen study does not cover the entire GIS, you are quick to point out that the Zwally study does, and that it also results in a net loss. So, accpeting the Zwally study and also rejecting the Thomas study is part of your argument, which is why I’ve tried to point out that the Thomas study is an equal if not better indicator of mass balance over the entire GIS.”
Yes, Jason, I am “not claiming that the IPCC has ignored ALL research”, as you say.
No, Jason: “accepting” Johannessen/Zwally and “rejecting” Thomas is NOT part of my argument.
And: “In addition, the Thomas study corrected for snow density, while the Zwally study used the density of ice everywhere.”
Believe you have that one wrong, Jason. Check the reports and you will see that Zwally has introduced a new concept for converting elevation change to mass balance by correcting for firn density, while Thomas does not make this correction and simply uses a density of 0.35 for gains and 0.92 for losses, as I indicated to you in my earlier post. In other words, Zwally corrected for firn density while Thomas did not.
Whether, despite this, Thomas is, as you say “an equal if not better indicator of mass balance over the entire GIS” [than Zwally] is a moot point and not really germane to our discussion.
But I am still waiting for your response to earlier posts.
Regards,
Max
December 6th, 2007 at 4:48 am
Max,
I hate to quibble over small discrepancies, but I truly think you’re wrong in your “correction” of my calcs. For example:
Where are you getting these numbers? Are you using the raw rates of gain and loss found in the Johannessen study without the 6 cm correction for isostatic uplift (70.4 cm and 22 cm)? Please provide more details on your calculation, if you’re going to try to correct me. I have already looked at the numbers carefully.
That’s fine and all, but you’ve ONCE AGAIN ignored the crux of my argument about the Zwally study, which is that it only utilized ATM data from 1993 to 1999. You’ve continually dismissed studies that use ATM data because the data is not sufficient, but somehow you’ve not applied this criticism to the Zwally study, which you just happen to agree with. Now, it seems to me that you are the one “ignoring published data” in your efforts to dismiss these other studies, while accepting the Zwally study. Please be consistent.
Yes, I know, but Bob’s calculation was centered around net mass balance.
This statement makes me wonder how you could possibly comprehend all of the relevant research on sea level contribution and ice mass balance, when you can’t even understand this simple calculation. I’ve already tried to explain to you how the conversion from rate of gain or loss to total gain or loss. Johannessen took the net rate of gain found in his study, multiplied by 11 years, and then subtracted 6 cm to correct for isostatic uplift. Therefore, if you’re going to calculate the gains and losses separately, you must treat them in the same manner. Please correct your numbers.
December 6th, 2007 at 6:19 am
Max,
Here’s my response to your argument:
This was basically the core of your argument. I can agree with you that the Johannessen study showed a more gains in the interior of the ice sheet than were previously known. However, I think your use of the term “paradigm shift” is a bit much. The thing to understand here is that what the Johannessen study changed was our understanding of accumulation in the interior. That’s all. It did not affect our understanding of the margins of the ice sheet, where the most losses are occurring, which brings me to my rebuttal:
The IPCC did not have to ignore (or reject) the Johannessen study in order to determine that there was a significant mass loss over the entire GIS. This is because at the same time the gains were occurring, there were also great losses in the marginal areas. This can be proven by combining the data from the Johannessen study with that of ATM/ICESat measurements for the margins. If you look at Table 1 in the Thomas study, you will see that the Johannessen study found a 64 mm/yr gain above 1500m. However, according to ATM/ICESat data over the same time period below 1500m, there was a net loss of 257 mm/yr. Putting the two together results in more sea level contribution than the IPCC estimated.
So, I will reiterate that the IPCC took Johannessen’s results into account, along with all of the other available research, in order to reach their conclusion of sea level contribution. It would not have been necessary for them to “ignore” or “reject” the Johannessen study. Now, you can continue to ignore or reject other studies in your attempts to prove the IPCC wrong, but you’d only be doing exactly what you’re accusing the IPCC of, so I’d recommend against it.
December 6th, 2007 at 6:23 am
Correction:
I meant to add one more phrase to my next to last sentence:
Should read:
December 6th, 2007 at 6:52 am
Hi Jason,
My, my!
Looks like you are getting a bit testy.
I just pointed out that the calculation you sent to Black Wallaby was slightly off, and then showed you that it was totally irrelevant in any case.
But please don’t let that stand in the way of responding to my earlier posts, as you have been doing so far.
You keep trying to discredit the Johannessen finding of significant net gain over his total GIS study area due to major growth in the vast interior and the enhancement/extension of this by Zwally to the entire GIS, which confirmed a net mass gain 1992-2003.
Why do you do this, Jason?
These studies are out there. Accept them and be happy.
I accept the Thomas study, despite its obvious shortcomings.
Why are you unable to accept the studies of Johannessen and Zwally, that show net gain of the GIS 1992-2003?
This is actually good news for us all, isn’t it?
If we believe these studies we do not really have to worry just yet of being swallowed up by 7 meter waves as Al Gore, James Hansen (and the UN Secretary General) pessimistically predict.
Isn’t this good news, Jason? Shouldn’t you be happy to know this? Why do you fret?
Cheer up, Jason. The world is not coming to an end.
But now, respond to my earlier posts.
Regards,
Max
December 6th, 2007 at 7:11 am
Hi Reasic,
REUR December 5th, 2007 at 2:42 pm
I think you got a bit of the over-excited “hots” there, you cuddly ol’ thing; quote:
“WHAT?!?! Are you crazy?! You PROPOSE, and then test for “reasonableness” by looking at a small map with your naked eye?! Let me do my own reasonableness test for you:”
You may have fingered a discrepancy somewhere in the published data, and/or in your calculations, but whatever it may be, it does not have much consequence, as you will find below.
Oh, and BTW, as a civil engineer, you should have had some practice at visually estimating percentage areas on plans and the like, so don’t give us that twaddle about your poor old naked eye. It was simply a TEST for reasonableness for a PROPOSAL …was there something ambiguous in my words?
Firstly, the PROPOSAL was based on several things, but mostly:
ONE: Please go again to OLA J’s Fig 1. If you have difficulty seeing it, or distinguishing the white areas from the pale blue, a) enlarge it, b) click-select it, and the image will darken, notably over the pale blue. I reckon the white areas within the thick black line delineating the edge of the GIS are of the order of 10%, and find it hard to conceive 25% as you propose. What’s your opinion, surely you have one, as an experienced engineer?
TWO: Reur December 1st, 2007 at 3:14 pm quote:
‘ [Certain data] … were excluded from the analysis, comprising 1-2% in the interior area and up to several tens of percent over margins…All of these exclusions amounted to about 30% of the crossover points over the whole ice sheet, most of which are from the marginal areas…”
COMMENT: from this, and what you made of it, I was perhaps being “generous” in suggesting 25% below 1500m, because the 30% is said to be in the marginal areas, which are lesser parts of the total area below 1500m.
The “ultimate wisdom” CIA World Factbook says : land: 2,166,086 sq km (410,449 sq km ice-free, 1,755,637 sq km ice-covered) (2000 est.)
OK, let’s do the sums again from your admittedly better approach of using a number for the total GIS area, (which I didn’t have before)
(1] Area surveyed above 1500m = 1,225.7a, which represents 98-97% of the area free of adverse surface anomalies for ERS.
(2] This represents an excellent sampling of the total area above 1500m, which means that the ~2.5% ABOVE 1500m can effectively be ignored. (and let’s also ignore the increase in effective area)
(3] % Total area NOT measured by ERS = (1755.6 - 1380.7)/17.556 = 21.4%
(4] % of Total area found BELOW 1500m NOT measured by ERS = 21.4 – 2.5 = 18.9%,
(5] Proportional TOTAL (NET) growth per Johannessen is: (100 - 18.9) x 54 = +4379 units
(6] Proportional TOTAL loss per Thomas for BALANCE is maybe: 18.9y = -4379 units.
(7] Required TOTAL rate of change y = - 231.7, which compares maybe with Thomson’s main extrapolation of – 45, but the whole thing is a “can of worms” anyway. Eg see below:
You should also consider these BRIEF points:
Quote 1 Thomas’s paper: “Nearer the coast, flight lines are too sparse for reliable interpolation in regions of high spatial variability, and errors may be locally quite large.” They also had temporal inadequacy, and ICESat was NOT AVAILABLE, NOT AVAILABLE, until AFTER, AFTER, the 11-year study period. In contrast, a substantial portion of the area below 1500m was much better CONTINUOUSLY measured by ERS! It seems to me that there must have been a great deal of “estimating” and extra-intra-polation by Thomas in the marginal areas!
Quote 2 “Here, we compare dS/dt from ERS with those from [later] satellite and [several sporadic May-June or June-July, but sparse] aircraft laser altimeters, to show reasonable agreement at higher elevation, where surfaces are nearly flat and horizontal…”
However, the coastal areas, in general suddenly plunge near the coast, whereas parts of the area below 1500 m are “flat enough” for ERS, (say 155a), with spatial AND temporal accuracy/relevance much greater than ATM, and all but about 2.5% above 1500m are also “flat”. However, there is a factor of difference in results of over 5 ABOVE 1500m, which is NOT “reasonable agreement”.
There also seems to be something rather “fishy” in the Thomas results for below 1500m vv below 2000m, but I can’t find enough data in the very scant Thomas report to finger it.
Thomas claims that Ola J’ only covered 80-90% of the GIS, (a rather broad estimate), but based on what is not evident.
OK, I’ll make an unsubstantiated claim too: That Thomas’s coverage was 80 -90 % of the GIS, but with MUCH POORER spatial and temporal coverage!….See if you can prove me wrong Reasic, you cutie!
CONCLUSIONS:
The Thompson assertion that the GIS suffered net loss, 1992 - 2003 is substantially wrong.
The Thompson paper contains a number of “questionable” statements, and is I think deliberately confusing, being almost a blog-topic in itself!
Cheers Black Wallaby.
December 6th, 2007 at 7:20 am
Hi Jason,
Let’s wrap this discussion up.
You wrote: “So, I will reiterate that the IPCC took Johannessen’s results into account, along with all of the other available research, in order to reach their conclusion of sea level contribution. It would not have been necessary for them to “ignore” or “reject” the Johannessen study. Now, you can continue to ignore or reject other studies in your attempts to prove the IPCC wrong, but you’d only be doing exactly what you’re accusing the IPCC of, so I’d recommend against it.”
Your “reiteration” is well put, Jason. IPCC “took Johannessen’s findings into account”. I suppose they also took Zwally’s findings of net mass gain of the GIS “into account”. Yet they made a claim that directly contradicted these findings, i.e. they ignored or rejected these findings, by definition.
Then you say (in your correction): “It would not have been necessary for them to “ignore” or “reject” the Johannessen study because losses measured in the marginal areas over the same time period outweigh the gains found in the interior by Johannessen (strangely contradicting and omitting any reference to the Zwally study, which extended Johannessen’s findings to the whole GIS and showed a net gain of ice).
You have not responded to the fact that Zwally corrected for fern compaction in his finding of net mass gain (which Thomas did not).
In your previous message you wrote: “The IPCC cannot make a determination that matches every single study. The fact that the ESA study and the IPCC’s findings are different does not mean that the ESA study was “ignored”. What you’re not getting is that the IPCC fully considered the increased gains in the interior, found by Johannessen and others. However, when those are combined with the losses that occurred in the margins over the same period, the result is a net mass loss. Zwally finds a net gain, but only uses ATM data to 1999. Thomas and Box find substantial losses overall.”
In other words, in all of the above you are saying that IPCC decided not to accept the conclusions of Johannessen/Zwally as correct because they had other reports that showed a different conclusion (which they considered to be more correct), and after weighing all the alternates objectively, they chose to accept the results of these other studies rather than the conclusions of Johannessen/Zwally. I have to admit that this sounds very logical, Jason, and could very likely be exactly what happened.
From the above statements it is clear, however, that you are now no longer denying my statement that: “IPCC ignored (i.e. did not accept or rejected) published data that contradicted its claim of ice loss in the Greenland ice sheet equivalent to a sea level rise of 0.21 mm/year over the period 1993-2003”, but you are, in effect, presenting me the reason WHY they did this (in your “opinion”), i.e. because Zwally “only uses ATM data to 1999” and “Thomas and Box find substantial losses overall”.
I could give you my “opinion” why they did this (and it does not pre-suppose a “sinister conspiracy” or even an intentional dishonesty on the part of the IPCC writers, which others may read into it): in “my opinion” they reacted to data points in the way Thomas Kuhn has described as typical in his treatise popularizing the theory of paradigms.
Those data points that support the prevailing scientific “paradigm” (of GIS ice loss due to AGW in this case) are quickly accepted by those that are stuck in this paradigm, while those data points that lie outside the paradigm (or even challenge the paradigm) are rejected or ignored, and then quickly countered with a new study that again reinforces the paradigm.
Johannessen’s 11-year study broke the prior paradigm of “high-elevation balance” of the GIS by conclusively demonstrating major growth in the massive interior, resulting in a significant net gain over his entire study area. Zwally enhanced and enlarged Johannessen’s paradigm-breaking conclusion to show growth over the whole GIS; he also added a new “paradigm shift”: correction for firn compaction in calculating mass balance from elevation changes.
Thomas stayed stuck in the old pre-Johannessen paradigm of “high-elevation balance” by ignoring Johannessen’s findings of massive increases in the vast interior areas and replacing Johannessen’s very comprehensive ERS-based numbers with ATM numbers (that did not even cover the entire measurement period) and showed less than one-sixth of the gain found by Johannessen in the interior >1500m, with a resulting net loss overall, as could well be expected.
You claim: “IPCC fully considered the increased gains in the interior, found by Johannessen”, but this is quite obviously not true, if you mean by “fully considered” that they “agreed” with them. They did, apparently, accept the Thomas study, and this study itself clearly does not agree with “the increased gains in the interior, found by Johannessen”. In addition, Thomas did not apply the firn compaction correction of Zwally to convert from elevation change to mass change, but simply stayed with the old paradigm of using the different densities of 0.35 for growth and 0.92 for loss, thereby exaggerating loss at the expense of growth.
IPCC may have “considered” (i.e. “reflected on” or “thought about”, as defined by Webster) the Johannessen/Zwally findings of overall GIS gain, as you state, but in the end they did not accept these findings (i.e. a net gain) in claiming just the opposite (i.e. a net loss). This means they actually rejected (or ignored) them.
Pondering on WHY IPCC did this is an interesting philosophical discussion, Jason, where you and I apparently have a different explanation (and Black Wallaby may have even a third explanation), but it is beside the main point. This point is that IPCC did, as has been shown beyond any shadow of a doubt, “ignore published data that contradicted its claim of ice loss in the Greenland ice sheet equivalent to a sea level rise of 0.21 mm/year over the period 1993-2003”.
Published scientific studies (Johannessen/Zwally) conclude GIS ice GAIN.
IPCC report claims GIS ice LOSS.
Therefore, IPCC ignores (i.e. fails to accept or rejects) the conclusions of these published scientific studies.
So YOU LOST THIS POINT in our discussion and we can now move on to Antarctica.
End of discussion. Whew!
Regards,
Max
December 7th, 2007 at 7:21 am
Hi Reasic,
Re Max’s December 6th, 2007 at 7:20 am, quoting you:
SORRY Max, I can’t resist this quote from Reasic:
“The IPCC cannot make a determination that matches every single study. The fact that the ESA study and the IPCC’s findings are different does not mean that the ESA study was “ignored”. What you’re not getting is that [1] the IPCC fully considered the increased gains in the interior, found by Johannessen and others. [2] However, when those are combined with the losses that occurred in the margins over the same period, the result is a net mass loss. [3] Zwally finds a net gain, but only uses ATM data to 1999. [4] Thomas and Box find substantial losses overall.”
[1] Reasic, could you please explain the grounds of your confidential knowledge of what the invested IPCC AUTHORS actually did when they CONSIDERED the paper of Johannessen, bearing in mind that it strongly CONTRADICTED THEIR OWN work, and consequently their pride, and maybe their prospect of continued funding? You and ‘motie have looked silly before, by omitting the appropriate conditional in statements such as ; “I think that”, and instead using the assertive; “I know” (when you have absolutely no basis for knowing!)
[2] Well for one thing, very briefly, when you say; “the losses that occurred in the margins over the SAME PERIOD”; do you mean that a few aircraft flights over SOME PARTS of the island in a few summer months in the years 1993, 1994, 1998 and 1999, are the same as the full-eleven-year satellite study period 1992 to 2003, 24/7? There are some other things you overlook, but will that do for one?
[3] You chastise Zwally for only using ATM data to 1999! However the total ATM data, for GIS is the same as used by your revered Thomas etc, being confined only to 1993, 1994, 1998 and 1999. So why doesn’t Thomas etc receive the same criticism from you?
[4] Thomas found losses based on almost laughable relatively primitive sampling when compared with Johannessen, whom very importantly found LARGE INTER-ANNUAL VARIABILITY, over a continuous eleven-year period, 24/7
Concerning Box et al, it is hardly necessary to go beyond the opening part of the abstract to that paper:
Regional climate model runs using the fifth-generation Pennsylvania State University–National Center for Atmospheric Research Mesocale Model modified for use in polar regions (Polar MM5), calibrated by independent in situ observations, demonstrate coherent regional patterns of Greenland ice sheet surface mass balance (SMB) change over a 17-yr period characterized by warming (1988–2004).
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Finally, I recommend you visit my latest “blog” on GIS, for some related releases that you may be unaware of. I’m JUST QUOTING WHAT IS OUT THERE, with its inherent contradictions! For some reason, my “blog” can’t be found under TAGS, but if you go to “Newest Journals” eg on the Home Page, it is currently #4 on the list.
I may edit it shortly to add some more interesting stuff to it, when I have time.
Cheers, Black Wallaby
December 8th, 2007 at 5:39 am
Hi Jason,
Still waiting for your response.
Regards,
Max
December 9th, 2007 at 9:04 am
Hi Reasic,
Max and me, and hopefully other visitors, are still in suspended animation, panting in anticipation with suffering breath, for your responses to Max’s compelling summaries above.
Oh Reasic (alias Jason), please don’t run away in defeat!
Prove yourself in humility, and concede that you were mistaken in some interpretations of various IPCC “STUFF”
CONSIDER THAT:
Max conceded one thing to you on a TECHNICALITY!
If you do not understand what I am saying, please ask, and I will elaborate.
It is time for you to concede on the Johannessen issue!
Meanwhile, I have posted another “GO Journal”, (#4) which is highly relevant….Check-out Newest Journels ….Greenland Melting…..
Cheers, Black Wallaby