Finally some recognition of all the anecdotal weather we’ve been talking about here – Anthony
World Meteorological Organization
Thu Aug 21, 2008 1:15am IST
LONDON (Reuters) – The first half of 2008 was the coolest for at least five years, the World Meteorological Organisation (WMO) said on Wednesday.
The whole year will almost certainly be cooler than recent years, although temperatures remain above the historical average.
Global temperatures vary annually according to natural cycles. For example, they are driven by shifting ocean currents, and dips do not undermine the case that man-made greenhouse gas emissions are causing long-term global warming, climate scientists say.
Chillier weather this year is partly because of a global weather pattern called La Nina that follows a periodic warming effect called El Nino.
“We can expect with high probability this year will be cooler than the previous five years,” said Omar Baddour, responsible for climate data and monitoring at the WMO.
“Definitely the La Nina should have had an effect, how much we cannot say.”
“Up to July 2008, this year has been cooler than the previous five years at least. It still looks like it’s warmer than average,” added Baddour.
The global mean temperature to end-July was 0.28 degrees Celsius above the 1961-1990 average, the UK-based MetOffice Hadley Centre for climate change research said on Wednesday. That would make the first half of 2008 the coolest since 2000.
“Of course at the beginning of the year there was La Nina, and that would have had the effect of suppressing temperatures somewhat as well,” Met Office meteorologist John Hammond said.
Hi John,
You wrote (of the Stearns et al. report: “The coastal portions of Kangerdlugssuaq and Helheim glaciers in southeast Greenland lost at least 51 +/- 8 km(-3) yr(-1) of ice between 2001-2006”.
This report was published in May 2007, three months after IPCC 2007 SPM, so obviously was not cited by IPCC.
It covers the period 2001-2006, and not the period cited by IPCC, i.e. 1993-2003.
It covered the coastal regions of southeast Greenland and not the whole ice sheet.
The Johannessen and Zwally studies DO cover the 1993-2003 time period, except as I told you, Zwally strangely truncated winter/spring 2002/2003 from the record, a period described by Hanna et al. (2007) as a period of “high snow accumulation”. But even ignoring this strange truncation, Zwally still comes up with net mass gain over the period. Correcting for his arbitrary truncation would have roughly doubled the net mass gain to around 25 Gt/year (rather than 11 Gt/year as reported).
You’ve got to come with something a bit better than these two reports, John.
Just cite me one report on GIS covering the entire period 1993-2003 which shows mass loss over this period.
Still waiting, John.
Regards,
Max
Hi John,
BTW, if you want to “break off” our discussion (as you hinted), I will understand why. You are losing the debate, and this is apparently unpleasant to you.
Any unbiased reader would come to this same conclusion.
I would prefer to continue, becasuse I have many more examples of IPCC disregarding published data that contradicted its claims. When you dig in a bit, you see that this is no isolated case with IPCC, John.
Regards,
Max
Hi John,
You quoted me as writing:
“IPCC states for Greenland: -0.21 ± 0.07, (i.e. a range of –0.14 to –0.28 mm/year). This is equivalent to a mass loss of –47 to –95 Gt/year.
Johannessen/Zwally measured for Greenland (using Zwally’s numbers that truncated one entire cold 6 months from the Johannessen record): +11 ± 3 Gt/year, which equals a mass gain of +8 to +14 Gt/year.
And you see no contradiction, not even any inconsistencies? ”
To this you replied (to my utter amazement): “No, I don’t, and I do not believe any reasonable person will say otherwise, since it is so obvious”.
Hey John, if you do not WANT to see obvious contradictions and inconsistencies, then you can stick your head in the sand and ignore them.
But, face it John, they are there, and as a “reasonable person” I can see them.
If I say that the Swiss city of Vevey lies 47 to 95 kilometers south of the city of Aigle while the map shows me that it lies 8 to 14 kilometers north of Aigle, there are obvious inconsistencies and contradictions in these two statements. One cannot be true if the other is. Its so simple, John.
All the double-talk in the world does not change the facts.
Regards,
Max
Hi John,
The report you quoted by Rignot et al. was published in 2008, so obviously could not be cited by IPCC 2007 SPM, and is therefore irrelevant to our discussion.
It covers three periods of a few weeks each using mass-budget calculations, but does not cover measurements over the entire 10+ year time frame under discussion.
Nice try, anyway, though.
Regards,
Max
Max,
It seems to me that you want IPCC to use only a few papers (which you constantly refer) and come to a conclusion, which would have been wrong in light of all the new information. I would say that IPCC had the insight to come to the correct conclusion in this case, which has been supported by new publications after the IPCC report was published.
“Please provide me another study covering the entire time period 1993-2003 for both Greenland and Antarctica that indicates loss of mass over this period, as falsely claimed by IPCC.
Just cite me one report on GIS covering the entire period 1993-2003 which shows mass loss over this period.
Still waiting, John.”
As I wrote earlier, they are summarized in Table 1 in Shepherd’s paper, as one example. I have noted that clearly in my earlier reply. One of those studies cover a longer period.
“BTW, if you want to “break off” our discussion (as you hinted), I will understand why. You are losing the debate, and this is apparently unpleasant to you.”
I am OK with whatever way you want to interpret it if that makes you happy. I make it a point not to insult the other person, not even to say that I am winning or they are losing. I leave those conclusions for the other readers, if they indeed want to make. Also, there were two others (Steve and Joel ) who broke off earlier, not necessarily because they were losing the discussion.
If I break off, that is because I do not have enough time to devote to analyzing details of papers in a field that will not help me at all in my own profession, in order to convince one person. I do not really want to know that level of details in another field, unless I have some intention of writing a paper or two in that field. In addition, for the one case we have been discussing, all those details did not cause me to change my earlier opinion anyway. Since I do not have the time to analyze tiny details of climate science, I just depend on the opinions of reputed scientific societies, like the National Academy of Science and Engineering (with the best and the brightest scientists). Almost every single scientific society (except one, American Society of Petroleum Geologists) came out and stated that they believe in AGW. If the National Academy say there is a problem (or contradiction) with IPCC’s statements, I will look into it more carefully. I have not seen that yet.
“To this you replied (to my utter amazement): “No, I don’t, and I do not believe any reasonable person will say otherwise, since it is so obvious”.
Hey John, if you do not WANT to see obvious contradictions and inconsistencies, then you can stick your head in the sand and ignore them.
But, face it John, they are there, and as a “reasonable person” I can see them.”
The general climate science community does not see a contradiction, and I do not see a contradiction between the IPCC data and that from others you cite. I do not know exactly why (how) you see a contradiction here. I really do not see one here.
Hi John.
I can see that you are still a bit confused here.
I stated that IPCC ignored (or rejected or refused to accept as correct) published reports that directly contradicted its claim of a net mass loss of the AIS as well as the GIS over the period 1993-2003.
I provided links to these reports, which are the ONLY reports that cover this period in its entirety and which both conclude a mass GAIN in both locations over this period.
You try several attempts to disprove my statement, but you always refer to reports that either do not cover this entire time period or that cover another time period entirely.
When I remind you that the time period of the IPCC claim is 1993-2003 and that reports covering subsequent time periods are of no relevance, you side-step and waffle very eloquently and with a lot of words, but you are unable to cite any studies that cover this entire time period, which show mass loss at either location.
To my repeated requests to do so, you send lengthy responses talking about all sorts of studies covering other time periods, but you bring no evidence covering the time period quoted by IPCC.
You then tell me that a range of –47 to –95 Gt/year is “not contradictory or inconsistent” with a range of +8 to +14 Gt/year. Ouch!
You finally conclude with a blanket statement: “The general climate science community does not see a contradiction, and I do not see a contradiction between the IPCC data and that from others you cite. I do not know exactly why (how) you see a contradiction here. I really do not see one here.”
If this statement were to be true, then it could well explain why “the general climate science community” has lost touch with reality (as you apparently have). I have pointed out the contradiction, so that even a 15-year old could see it.
Forget the broad-brush statements about the “general climate science community”, John. Either show me a report covering the time period cited by IPCC that confirms its claim of a net ice mass loss or admit that you cannot do so, so we can move on.
The time for waffling is over, John. Bring the facts or admit that you do not have them.
Regards,
Max
Max,
Max, “When I remind you that the time period of the IPCC claim is 1993-2003 and that reports covering subsequent time periods are of no relevance, you side-step and waffle very eloquently and with a lot of words, but you are unable to cite any studies that cover this entire time period, which show mass loss at either location.”
I have said this over and over, look at Table 1 in Shepherd, it gives a summary of a number of studies, where they say the overall AIS change between 1992 and 2006 is –136 Gt/year to 43 Gt/year, and the error estimation is very large. For GIS it is between –227 and 11 Gt/year. Yet you pick only those data that supports your conclusion. To outline a few items:
(1) You have imposed very narrow conditions on IPCC, it has to be a satellite data, only a study covering 1992-2003 is admissible (you cannot reconstruct this with two studies, 1993 to 1996 and 1996 to 2003), etc.
(2) You completely ignore Zwally’s work (Journal of Glaciology, 2005) on Antartic, covering 1992-2002 period showing AIS change of -31 ± 12 Gt/year, because you insist on 1993-2003 even though the duration is the same (unless of course there was an anomaly in 2003 – it which case it is just that, an anomaly).
(3) You ignore Wingham’s new interpretation in Shepherd & Wingham using the same or extended data, you insist on using only Wingham’s old interpretation.
(4) You want to discount all new papers published after IPCC report, even though the new reports are consistent with IPCC’s interpretations – seems like you are very interested in what is happening out there.
(5) You discount error estimations and you seem to give higher probability to the mean value, although it is equally probable to be anywhere within the range defined by the error estimates.
IPCC’s report was about global warming. Most of these papers explicitly state that ice growth at higher elevation is a direct consequence of global warming (“Thinning at the margins of the Greenland ice sheet and growth at higher elevations is an expected response to increasing temperatures and precipitation in a warming climate.” from Zwally). Yet, you like to ignore the entire forest and work on the trees.
These are my reasons that we will never get to a conclusion.
“The time for waffling is over, John. Bring the facts or admit that you do not have them.”
It is not waffling when I say I STRONGLY DISAGREE with your premise, your methodology and your conclusions.
Max, I should have said “– seems like you are not very interested in what is happening out there.
Hi John,
Your last message was wordy enough, but did not address the issue at hand. You did not respond to my request to “bring the facts or admit that you do not have them.” You did neither, but just rehashed a bunch of stuff that is irrelevant to the issue at hand.
Let me first respond to your statement concerning the Shepherd et al. report. You wrote: “I have said this over and over, look at Table 1 in Shepherd, it gives a summary of a number of studies, where they say the overall AIS change between 1992 and 2006 is –136 Gt/year to 43 Gt/year, and the error estimation is very large. For GIS it is between –227 and 11 Gt/year. Yet you pick only those data that supports your conclusion.”
Yes, John, I have looked at Table 1 many times (even prior to your advice to do so). It is irrelevant to our discussion here for several reasons, which I will outline below. These have absolutely nothing to do with my picking “only those data that supports your conclusion” (as you have erroneously claimed). I will explain so (I hope) you can understand.
Some days ago I made the statement, based on the observed facts, that IPCC ignored (or rejected or refused to accept as correct) published studies based on continuous satellite measurements plus other methods and estimates for the areas where satellites cannot get an accurate reading, which showed a net gain in both the Antarctic and Greenland ice sheets over the period 1993-2003 when it made its claim of a net loss of ice mass in both ice sheets over exactly the same time period.
The published studies I cited were Johannessen/Zwally for GIS and Wingham et al. for AIS.
You came back with all sorts of arguments.
First you said, well part of the range of error in one study is included in part of the range in the IPCC claim so (although the conclusions are directly opposed) there is no real contradiction.
I pointed out to you that your generous rationalization (for IPCC) is false for the GIS, where there is no overlap whatsoever in the error ranges, and that it is illogical for the AIS, since the observations conclude net mass gain while IPCC claims net mass loss.
You still fail to see a contradiction, and refer me to several studies that show different results than the three I had cited.
I checked these all out and found that:
· Many of the studies (including Shepherd et al.) came out after IPCC 2007 SPM and could therefore not have been considered when IPCC made its claim (these are the studies, using newer methodologies, such as GRACE, which also show the highest rates of loss)
· Some studies, which came out before IPCC 2007 SPM covered small pieces of the 1993-2003 time frame or small parts of the entire ice sheets, but NONE of the reports covered the entire 1993-2003 time period and the entire ice sheet (notable among these are the studies by Rignot et al. using mass budget calculations and covering a few months in 1996 and in 2000, which also show very high rates of loss)
The Shepherd “Table 1” which you cite gives a summary of some of these reports.
Another more complete summary for Greenland is given in Thomas et al. (2006). This report also includes:
· Airborne Topographic Mapper (ATM) and ATM/ICESat results covering a small portion of the GIS nearer the coast for two summer periods within the 1993-2003 time frame
Yes, John, there are many studies out there. This is not the point.
The point is that there are only the Jahannessen/Zwally (GIS) and Wingham et al. (AIS) studies that measured the 1993-2003 time frame (quoted by IPCC) continuously, and these reports showed a NET GAIN IN BOTH AIS AND GIS OVER THE PERIOD 1993-2003.
And, John, these are precisely the published reports which IPCC ignored (or rejected or refused to accept as correct) when it made is claim of net ice mass loss over this period in its IPCC 2007 SPM report.
They did not ignore OTHER reports, and I never made that claim.
They could not possibly have even considered the Shepherd et al. report which was published after they published, so this report is irrelevant to my claim.
Is all of the above clear enough for you?
I have told you that if you can provide me a link to a report, which covers measurements over the entire 1993-2003 period for either the GIS or the AIS and which concludes that there was a net loss of ice mass over this period, then I will reconsider my statement.
You have not been able to do this, John. Face it like a man.
Regards,
Max
Max, “Face it like a man.”
I am sorry, I would like to stay away from discussions on whether I am a man or not, they are not relevant.
The reports summarized in Table 1 in Shepherd were published before the IPCC report. You completely ignored Zwally on Antartic. The problem is that you want to consider (and you want others to consider) only those papers that satisfy your selection criteria, meaning only one or two papers, and make a conclusion based on that. You do not want to consider uncertainties and error estimates.
It seems you have used this strategy (of taking one or two papers as the ultimate proof for the claim you are making while ignoring the rest) many times, that is why I am pessimistic about any conclusions from this discussion. This is not new, as Gavin once wrote in response to your comment [Yet, this comment takes a single apparently favorable result as gospel, ignores all other evidence for significant sensitivity and encourages us all to pack up are things and go home. No uncertainty there. Instead a dogmatic certainty that everything the scientific community has been worried about can be dismissed with a stroke of Roy Spencer’s pen. It must be a comforting philosophy – though not one that is likely to survive more frequent brushes with reality]. That was about your comment on Roy Spencer’s paper. Unfortunately you are using exactly the same pattern of argument here. Select only one or two papers, saying that those are continuous measurements, neglect the rest (even if they are continuous, like Zwally on Antartic), and make the argument only based on those chosen papers. You do not even want to take into account the new interpretation for the same data (1993-2003) and extended data in Shepherd by the same author.
That is why I disagree with your premise, methodology, and conclusions.
Hi John,
You just wrote, “You completely ignored Zwally on Antartic. The problem is that you want to consider (and you want others to consider) only those papers that satisfy your selection criteria, meaning only one or two papers, and make a conclusion based on that. You do not want to consider uncertainties and error estimates.”
This is a rash accusation based upon a silly and erroneous conclusion, as I will demonstrate to you.
I did not “ignore Zwally on Antarctic” at all, as you have stated. If you actually read it you will see that Zwally’s study on Antarctica covers the period mid-April 1992 to mid-April 2001.
Wingham has already calculated a mass balance for the time period mid-April 1992 to mid-April 2003 and has extended this to the whole AIS by adding estimates for the non-measurable areas.
In effect, Zwally’s study recalculates Wingham’s numbers by adding in some “optimum interpretation” and truncating the last two years of Wingham’s study.
Since it does not include the last two years of the 1993-2003 time frame cited by IPCC, it is a poorer choice than the Wingham report for verifying the IPCC claim.
My “selection criteria” include that the report should include the entire time period of the IPCC claim, which Zwally’s study on the AIS clearly does not. All seems pretty clear to me.
I’ll respond to the rest of your post separately, but thought I would clear you up on this point first.
Got it?
Regards,
Max
Max, “In effect, Zwally’s study recalculates Wingham’s numbers by adding in some “optimum interpretation” and truncating the last two years of Wingham’s study.”
So ?? Zwally came up with -31 ± 12 Gt/year estimate. Wingham came et al has 27 ± 29. Two years made that much difference? That is why Shepherd’s interpretation is more important.
Hi John,
Back again.
You seem to be getting a bit distraught and emotional here when you write, “It seems you have used this strategy (of taking one or two papers as the ultimate proof for the claim you are making while ignoring the rest) many times, that is why I am pessimistic about any conclusions from this discussion.”
Now calm down, John. You are making rash assumptions again. I have told you time and again that I have seen an IPCC claim of net ice mass loss in GIS and AIS over the period 1993-2003, and then looked for actual observed data covering this same time period.
What I found was that the ONLY reports that cover the exact time period of IPCC are the Wingham et al. report for AIS and the Johannessen/Zwally reports for GIS, where I noted that Zwally had curiously truncated six winter months from the Johnnessen study.
I saw that the ONLY reports, which covered the time frame of the IPCC claim all showed NET ICE MASS GAIN rather than loss as claimed by IPCC.
I hunted and scoured the published data and (like you) I was unable to find ANY studies which covered the entire time period 1993-2003 and which showed that there was a loss of ice mass over this period.
So I concluded that IPCC ignored (or rejected or refused to accept as correct) published reports covering the period 1993-2003, which showed net growth of both the AIS and GIS over the period when it made its directly contradictory claim of ice mass loss over this period.
And that is the statement I made that started our exchange.
And you have been unable to refute this statement with facts, John.
Studies covering other time frames or other locations do not count.
Now to your side-track that I have resorted to quoting single studies as expressed by (of all people) Gavin Schmidt, let me say this:
1. It is a diversionary comment intended to move the eye off of our discussion, where you are experiencing a bit of a problem
2. Gavin Schmidt is a poor reference choice; unlike this site, which allows all messages to pass through the filter, which are on-topic and do not contain any unsuitable wording, Gavin’s RealClimate site is notorious for censoring out anything that disagrees with his viewpoint; in addition Gavin himself tosses in his own remarks which include direct name calling and occasional ad hom attacks, all of which makes blogging on RealClimate a total waste of time.
Face it John. Despite all of your accusations and waffles you have been unable to cite a report covering measurements over the entire time period 1993-2003, which concludes that there was a net ice mass loss in either the AIS or the GIS over this time period.
Until you do, my statement stands as correct.
Regards,
Max
Hi John,
I’ll hand it to you for sheer perseverance and determination, if not for logic, when you post this statement: “Zwally came up with -31 ± 12 Gt/year estimate. Wingham came et al has 27 ± 29. Two years made that much difference? That is why Shepherd’s interpretation is more important.”
Another diversionary waffle, John.
Are you saying that Wingham et al. got it wrong when they reported 27 Gt for 1992-2003?
I can’t say how much difference two years can make (and neither can you), but I am saying that Zwally only looked at 1992-2001, so is not directly comparable with the IPCC claim for 1993-2003, while Wingham et al. is. Can you explain why this should notbe true?
I also pointed out to you that the later Shepherd et al. report came out after IPCC 2007 SPM was published, so could not possibly have been considered by IPCC.
Your thinking is becoming a bit convoluted as we move along here, John.
Regards,
Max
PS Unless you bring some specific reports covering the entire 1993-2003 time frame, which show net ice mass loss in either AIS or GIS, I m not going to continue answering your posts, and suggest we move on to the sea level discussion, as we have truly beaten the AIS/GIS dog to death.
Max,
(1) “Until you do, my statement stands as correct.”
That is a strange logic. It is almost like (just to give a strange example) someone standing on the top of the building saying that “I believe that nothing will happen to me if I jump down, and my statement stands correct, unless you can prove me wrong”.
Now, you are entitled to your own belief, with your own justification. I disagree with your reasons for that justification, and your conclusions. As I will argue in the last paragraph, I have my own reasons to arrive at a different conclusion.
(2) “So I concluded that IPCC ignored (or rejected or refused to accept as correct) published reports covering the period 1993-2003,..”
No, they accepted more reports to get a composite value, instead of accepting just one or two reports that you had hoped them to accept.
(3) “You seem to be getting a bit distraught and emotional here when you write … Now calm down, John. You are making rash assumptions again.”
I hope you stay away from characterizing my psychological state, since you are constantly making the wrong conclusions in that area. I am not getting a dime from this discussions, the only reason for responding to you is simply pleasure – pleasure to see how people argue and respond. If it is not enjoyable, I would have just stopped it long ago.
(4) “Gavin Schmidt is a poor reference choice; unlike this site, which allows all messages to pass through the filter, which are on-topic and do not contain any unsuitable wording,..”
I do not read RealClimate, but it looks like they posted all your postings even though you were not in agreement with that crowd. I used Gavin’s comment because I pretty much agree with his observation about your argument. It was used to reinforce my observation about our discussion, not as a diversion.
And finally, as the most important item:
(5) “Are you saying that Wingham et al. got it wrong when they reported 27 Gt for 1992-2003?”
When Wingham’s study for 1992-1996 shows -60 ± 76 Gt/year and Zwally (1992-2002) shows -31 ± 12 Gt/year, then I think there are justifiable reasons to doubt the reliability of Wingham’s report for 1992-2003 showing 27 ± 29 Gt/year; or at least there is the need to look for additional explanations. Given that, it is just reasonable for IPCC to use a composite result rather than depending on just one or two reports, and I suspect that is what IPCC had done since there is so much variations and uncertainty with the results. I am not saying that Shepherd’s conclusion should have entered in the IPCC report, but I think IPCC got it right in light of Shepherd & Wingham’s modified conclusions. Those are my reasons in believing IPCC’s conclusion, in addition to what the National Academies of all over the world have to say. Based on that justification, I have no trouble in holding on to my conclusions. If there are justifiable reasons to change my opinion, I would do it; but this is not one of them.
Hi John,
Let me see if I can try to understand your logic here, John, so we can cap off our discussion on IPCC claims regarding GIS and AIS.
First of all, you have stopped talking about GIS, where IPCC ignored (or rejected or refused to accept as correct) the conclusions of Johannessen/Zwally that GIS gained mass overall from 1993-2003. This gain in mass was explained as having been due to massive snowfall in the previously barely measured higher altitude interior, which had previously thought to have been in balance. Despite this new information covering the same time period of their claim, they still claimed a net mass loss, in direct contradiction to the observed facts. There is not even a small overlap of the ranges between the J/Z observations and the IPCC claim. This is an obvious case, so you moved on to AIS, where the case is less obvious, according to your logic.
You do seem to be agreeing that IPCC did ignore the Wingham report, but say that this is so because they knew that future reports would come out with something else, and since future reports (covering another time period), did indeed show a net loss they were vindicated in doing so in hindsight. Is this sort of like model forecasting? Sounds like very dubious logic to me, John.
Now to your claims that Zwally and later Shepherd refuted Wingham, let’s test the logic there, John.
You wrote: When Wingham’s study for 1992-1996 shows -60 ± 76 Gt/year and Zwally (1992-2002) shows -31 ± 12 Gt/year, then I think there are justifiable reasons to doubt the reliability of Wingham’s report for 1992-2003 showing 27 ± 29 Gt/year.
Zwally indeed shows –31 Gt/yr net loss in AIS over the period April 1992-April 2001.
Wingham reported a net mass gain of 27 Gt/yr April 1992-April 2003 (covering time period of IPCC claim).
All studies report large inter-seasonal and inter-annual fluctuations, so the Zwally and Wingham reports are not contradictory at all. They just cover different time periods. And Wingham just happens to cover the time period of the IPCC claim, while Zwally falls two years short of doing so. So Wingham is clearly the more pertinent report for checking the validity of the IPCC claim.
IPCC does not cite Wingham and claims net mass loss 1993-2003.
After IPCC is published, Shepherd consolidates data from several studies covering periods outside the 1993-2003 time frame, confirms the 27 Gt/yr net growth over the period 1992-2003 found by Wingham, adds an estimate of –60 GT/yr mass loss over the period 1993-2006 and shows that all the studies cited lie within a range of –139 to +42 Gt/yr (with the major losses being shown in GRACE studies covering periods after the 1993-2003 the time frame).
For purposes of backing IPCC 2007 SPM, we can ignore the Shepherd report, which was published after IPCC, but we see that it in no way contradicts the Wingham finding of 27 Gt/yr over the period 1993-2003. Again, a net mass loss of –60 Gt/yr from 1993 to 2006 is in no way contradictory with a net mass gain of 27 Gt/yr from 1993 to 2003. Just means there was more run-off and melting and less snowing from 1993 to 1996. And the main difference is that they cover different time periods (as was the case for Zwally).
So you see, John, that it remains valid that IPCC ignored (or rejected or refused to accept as correct) published reports that showed net mass gain in both GIS and AIS over the time period 1993-2003 when they made the directly contradictory claim of net mass loss in both ice sheets over the same time period.
That is what I said at the very beginning and that is what still holds after this long exchange between us.
You have been unable to refute my statement but very eloquently explained to me HOW IPCC ignored these reports, i.e. by gathering all other data that showed loss over some piece of the ice sheet or some portion of the time frame and giving these higher weighting than those reports that covered the whole time period with continuous measurements. This is the HOW. I think we both know WHY they did this.
Had all the partial reports shown a net gain and only the Johannessen/Zwally and Wingham reports shown a net loss, IPCC would also have claimed a net loss.
Hey, John, it’s their “message” (and “raison d’être”). AGW is causing ice caps to melt and sea levels to rise. Got it?
Let’s move on to their dubious claims on sea level, if you are still in the mood to continue.
Regards,
Max
Max, Thanks, but you said, “but we see that it in no way contradicts the Wingham finding of 27 Gt/yr over the period 1993-2003. Again, a net mass loss of –60 Gt/yr from 1993 to 2006 is in no way contradictory with a net mass gain of 27 Gt/yr from 1993 to 2003.” etc.
This is one of my problems, you are not accounting for the error estimates. Things are not all that certain all the time, the error range is important in judging whether or not IPCC report is justifiable.
I usually use the word “contradiction” very carefully. There is no contradiction there. But from 1992 to 2002 we have -31 ± 12 Gt/year, from 1993 to 2003 we have 27 ± 29 Gt/year and Shepherd’s statement a year later “It is reasonable to conclude that, today, the EAIS is gaining some 25 Gt year–1, the WAIS is losing about 50 Gt year–1” certainly raises questions about the reliability of some of these results.
“IPCC does not cite Wingham”, On this I agree. I do not know why they did not cite that. I might send him an email to ask exactly what his opinion is about that, rather than speculating about the reasons.
GIS: the range is very large – Krabill -47 (no error) for 1993-1999, Zwally 11 ± 3 (1992-2002) but for 1996 -83 ± 28; Rignot -127 ± 28 for 2000; Velicogna -75 ± 21 (2002-2004), etc. Reconstructed trend from these data does not agree with Jahannessen. IPCC again took a composite measure. Again, I do not see any reasons to disagree with their report.
Hi John,
Looks like we have agreed to disagree.
You have a hard time finding contradictions and are generous in your rationalizations of any inconsistencies in the IPCC report.
I am a bit more rationally skeptical.
The only reports, which covered the entire time period of 1993-2003 cited by IPCC are Johannessen/Zwally for GIS (with the excpetion, as I noted, that Zwally truncated one 6-month period of cold weather from the end, i.e. October 2002 to April 2003) and Wingham for AIS. These are precisely the reports that showed net growth over exactly the same time period that IPCC 2007 SPM claimed net loss.
Both came out before IPCC.
Wingham covered the entire AIS: 72% with satellite measurements and the remaining 6% marginal coastal areas plus 22% interior areas too near the pole with calculated estimates.
Johannessen/Zwally covered the entire GIS: 90% with satellite measurement, a further 3% with ATM data to cover the margins and a final 7% using “optimum interpolation procedures”.
These are the facts. They led me to conclude (as I stated in the very beginning), IPCC ignored (or rejected or refused to accept as correct) published reports that showed net ice mass gain over the period 1993-2003 over the entire AIS and GIS when they made their claim of net ice mass gain over exactly the same period.
This statement has been validated by our exchange.
You tell me that subsequent reports covering later time periods showed net mass loss; I do not disagree with your statement.
You mention an ATM study by Krabill et al., which covers 12% of GIS surface area (the coastal part) over two short summer periods within a different time period, ignoring the vast, high elevation interior. (Yawn!)
You cite a “mass budget” study by Rignot and Thomas covering 51% of the AIS for a few months in 1996 and 2001. (Snore!)
You throw in later GRACE studies by Veliconga et al. outside the IPCC time frame. (Ouch!)
And then you tell me that “reconstructed trend from these data does not agree with Johannessen” [and Zwally or Wingham]. I agree. It certainly doesn’t, either in scope of coverage, period of coverage or conclusion.
You write that you “do not see any reasons to disagree with their report”. Nor do I, John. These reports are certainly valid for the scopes and time frames they cover.
But none of the studies you cite measured the entire GIS or AIS over the entire 1993-2003 time period, as Johannessen/Zwally and Wingham do. So their conclusions are really irrelevant to our discussion, as I said all along.
I am still open on this. If you can show me a report covering the entire GIS and the entire AIS showing net mass loss over the entire period 1993-2003, I will agree that there is uncertainty about the validity of the IPCC 2007 SPM claim.
Until you do, however, I will maintain that IPCC ignored Johannessen/Zwally and Wingham when they made their contradictory claim of mass loss in AIS/GIS over the period 1993-2003.
Regards,
Max
Max, “Until you do, however, I will maintain that IPCC ignored Johannessen/Zwally and Wingham when they made their contradictory claim of mass loss in AIS/GIS over the period 1993-2003.”
I do not disagree on what you should believe, I am fine with that. I only take issue if say those beliefs are the correct ones.
“I will agree that there is uncertainty about the validity of the IPCC 2007 SPM claim.”
and in all those reports you cite (as shown by the error estimates).
“But none of the studies you cite measured the entire GIS or AIS over the entire 1993-2003 time period, as Johannessen/Zwally and Wingham do. So their conclusions are really irrelevant to our discussion, as I said all along.”
I have already addressed this. Just because a study is continuous does not mean the results are correct or reliable. I do not trust conclusions based on satellite data, unless it is verified and re-verified by other teams. You bring the coverage area; there are other studies which cover larger area. Again, area itself is not important, one can focus on a small area with higher activities and neglect vast other areas with relatively small level of activities, and could get better results than covering the whole area. These are complicated issues, and I am happy to leave them to the experts to decide.
Dear Mike Bryant,
Thank you! Sorry for the long delay – I was traveling. After coming back I was planning to send Jeff Alberts’ comment to an Indian Forum, which would have produced a large increase in the number of Indians posting here. But I will not.
About India and math, I know that Aryabhata developed some basic integral calculus to measure volume – India’s first satellite was named after him. But Egyptians knew some basics in 1700 BC. Didn’t the Iraqis do something too – Alhacen? Credit goes to many. Jesuits came much later – 1500 AD. I think Indians had some expansion for square root of 2, in Jaina period they had reference to zero (300 BC), etc. I was working in Kerala (southern Indian state) for a while, I know that infinite series, some calculus, and trigonometry was taught in Kerala much earlier than when Jesuits came there – so there is good chance they took that knowledge through the trade route, since it appeared in the West only in late 17 th century.
Thank you for your comments. Since I am a computer engineer I can only say so much on this – we need a science historian to get more complete information – if you are interested I will find one.
Regards,
Rama Sundaran Sharma
Dear Mike Bryant,
I am so impressed by your knowledge about these things: about a distant place for such a long time ago.
Rama Sundaran Sharma
Rama Sundaran Sharma,
Americans hold only respect for Indians. I believe I read a short article that explained the evidence for the theft of Indian mathematics by the Jesuits. The article was at physorg.com.
Thank you for reconsidering an action that I believe would be counterproductive.
I am curious if there is a skeptical community of Indians in, or even outside of, India. I am also curious what you, as a well-educated individual, think about the issue.
Perhaps you could comment on what you believe, and also what you feel that most educated Indians believe.
Also you might comment on proper and improper ways to reply to Indians, to avoid insults and miscommunications, As you know Americans are among the most brash and irreverent people in the world. I do not believe this to necessarily be a bad thing, but when it gets in the way of honest communication, it becomes very undesirable.
Thanks for your reply,
Mike Bryant
Mike Bryant,
Now who are we going to fight after Iran, Russia, China, Mexico (if it gets too cold) or Canada (if it gets too hot). You peacemaker you.
The Indian scientists I have known over the years were some of the most sarcastic and funniest people I have ever met in my entire life. I wouldn’t worry too much about cultural mores.
Good one Poet