Bishop Hill Glacier loss of plot
Aug 15, 2014 Climate: WG2 This morning's must-read scientific paper comes from Science, where a team from the University of Insbruck led by Ben Marzeion has been looking at glacier recession. The results seem to have pleased the green fraternity, and a glance at the abstract shows why:
The ongoing global glacier retreat is affecting human societies by causing sea-level rise, changing seasonal water availability, and increasing geohazards. Melting glaciers are an icon of anthropogenic climate change. However, glacier response times are typically decades or longer, which implies that the present-day glacier retreat is a mixed response to past and current natural climate variability and current anthropogenic forcing. Here we show that only 25 ± 35% of the global glacier mass loss during the period from 1851 to 2010 is attributable to anthropogenic causes. Nevertheless, the anthropogenic signal is detectable with high confidence in glacier mass balance observations during 1991 to 2010, and the anthropogenic fraction of global glacier mass loss during that period has increased to 69 ± 24%.
An abstract written with headlines in mind, I'm sure you will agree.
The results are currently being trumpeted by, among others, the Carbon Brief:
69±24% of glacier loss since 1991 was caused by humans - Science
Chris Hope:
Man-made warming becomes main cause of glacier retreat, study says
and Bob Ward:
New study concludes about two-thirds of glacier mass loss worldwide in last 20 years is due to human activities
There are many others too.
So. let's take a look at how this startling conclusion was reached.
...we quantify the evidence for a causal link between anthropogenic climate forcing and observed glacier surface MBs [mass balance], not of individual glaciers but of all the world's glaciers outside of Antarctica combined. We then attribute the global glacier retreat since 1851 to natural and anthropogenic causes. We use a model of global glacier evolution that treats the MB of each of the world's glaciers contained in the Randolph Glacier Inventory (RGI)... individually, including a simple parametrization of ice dynamics leading to glacier hypsometry change... Forced by observed climate... the glacier model has been independently validated against both annual surface MB observations (fig. S1) and observed, temporally accumulated volume changes of hundreds of glaciers...
For each of 12 reconstructions of the global climate between 1851 and 2010, produced by general circulation models (GCMs) from the CMIP5 ensemble... we reconstructed the area and volume of each glacier in 1851... From this reconstructed glacier state, we modeled the evolution of each glacier forward in time. This forward model was run twice for each GCM: once subject to all known forcings (i.e., solar variability, volcanic eruptions, land-use change, anthropogenic aerosols, and greenhouse gas emissions; we call these model runs the FULL runs below), and once subject to only natural forcings (i.e., solar variability and volcanic eruptions; we call these model runs the NAT runs below).
So if I understand this correctly, we take the CMIP5 models - the ones that failed to predict the recent hiatus in global surface temperature rise and which, by mainstream climatologists' own admission don't include an important part of the climate system, namely heat transport to the deep oceans. Then, despite the fact these models have no known ability to reproduce regional climate either we use their output to feed glacier simulations, which include their own parametrisations. And from this conclusions are drawn.
It's models upon models upon models. And models, moreover, that are known to be unsuitable.
And from this our green friends expect us to accept their entirely uncaveated statements about glacier retreat.
Amazing.
Reader Comments (70)
I'm amazed that your still amazed by this entirely predictable piece of guesswork.
Green acquaintances have been rejoicing, yes.
All MB calculations are based on guesswork. How many glaciers were actually visited? There are several thousand. Observations have shown that Kilimanjaro glacier loss was due to reduced precipitation not rising temperatures. These are currently growing due to increasing snow.
If the model fails to match reality the model is wrong not reality.
Just the latest in a production line of press-release papers. They move from 'crisis' to 'crisis', producing a new report for each subject, breathlessly intoning disaster. And of course it's always, always our fault. It makes for a brilliant grant-seeking business model.
Models show that the missing heat has migrated to the deep oceans. Observation and empirical measurement from the Argo buoy system has no record of this heat movement.
I repeat my model/reality claim.
These people are stark, raring bonkers......
"The ongoing global glacier retreat is affecting human societies by causing sea-level rise, changing seasonal water availability, and increasing geohazards."
Is this a conclusion from the study or just a copy-and-paste job from the massmedia?
It is amazing that journals accept papers like that. Have they no standards?
Also, when the greens celebrate this sort of stuff they demonstrate that they lack integrity.
Reading some papers is a bit like watching performing seals in a circus (they had them in the olden days). They do some impressive tricks for their masters to catch our attention and help bring in the money, but you feel that it is not very natural and that everyone involved really ought to have better things to do with their time. No least the audience.
We have had to endure decades of tricks, from Wirth's sabotaging the congressional hearing to which he had invited Hansen to perform in in '88, through the sundry distortions of the IPCC (hurricanes, hockey sticks, glaciers, peer-review, sea levels, eco-activists in leading roles, SPMs ahead of reports, Madrid 1995 - deleting the not in 'not discernible', and no doubt many more that I fail to recall off the top of my head), through sundry campaign-wheezes like disappearing polar bears, disappearing Tuvalus, disappearing snow in the UK and on Kilimanjaro (to name but two), child-scaring guff such as 'An Inconvenient Truth' and government-sponsored scare-ads, PR agencies selling us the sizzle because the sausage is crap, the glimpses behind the sorry scenes afforded us by the Climategate Revelations, silly surveys producing 97%s out of various hats, and so on and on, through research papers assisting alarmism on which the virtual ink is scarcely dry before they are shredded by concerned citizens taking the time to check their data, if they can get it, and/or their reasoning, if they can find it.
The Climate Circus, full of scares and packed with tricks. Is it time to get rid of it as cruel and degrading? It has been so lucrative for so many, and ticket sales still seem to be high that it will be no easy task. As the cliche goes, it will probably collapse under the weight of its own contradictions, but what further harm could it cause in the meantime? Perhaps the process would be greatly speeded up if more insiders were to come out from under the tent and declare to all the world what rot and rottenness they have left behind?
While we're waiting, here's a skit involving glaciers, models, and carbon footprints that you might find amusing...
it's models, all the way down!!
Hannibal and his elephants will be very happy to hear the passes they used to invade Rome are re-opening.
This isn't science as hard scientists know it.
Glaciers retreat because of LACK of snow and rain
were we not supposed to have more of it , everywhere ?
"69% +/- 24%"....hmmm that sounds like a call for a math problem.
Let's see:
69 - 24 = 45
And the earlier period estimate is given without error bars.
So 24 is 34% of 69.
Let's just assume that they meant to apply their 34% error bar to the prior "estimate".
And forgot, since that would make their current claim just another crap made up bit of publicity seeking moral hazard action seeking yet more money from the public trough.
Lord Deben's twitter stream is bonkers...
https://twitter.com/lorddeben
" ..... the fact these models have no known ability to reproduce regional climate ...."
Better is ' .. the fact these models have known ability to not reproduce regional climate ...'
I'm sure this paper will feature in "The All Time Worst Compendium of Climate Bollocks" at sometime in the future.
.........and of course they miss out the pesky Antartic glaciers that have been expanding!
'Click to read more'...
Your Grace, please find attached a note from my Mummy excusing me from 'reading more' on account of it causes me to start shouting at the screen; pulling my hair out, and generally resulting in all sorts of mental anguish...
Please publish an article which says: 'Greenies/alarmists/politicians proved conclusively wrong on climate/CO2. UK population allowed to bring a class action for damages..'
all known forcings (i.e., solar variability, volcanic eruptions, land-use change, anthropogenic aerosols, and greenhouse gas emissions;
Precipitation? Where it gone?
Why "outside of Antarctica"?
If I had put forward an expression of...
"Here we show that only 25 ± 35% of the global glacier mass loss during the period from 1851 to 2010 is attributable to anthropogenic causes."
...my boss (quite correctly) would have presented me with my P45. What does it mean?
One of the authors is Graham Cogley. He's good - he won't do alarm. But he needs to get Science papers too!
This is the paper's concluding paragraph:
Carbonbrief deserve to be rapped on the knuckles.
So, let me get this right. This paper is silly/rubbish/wrong because it used models that failed to predict something that they were largely unable to predict. Is it just me, or does that just seem like rather a silly argument? (probably no need this question as I suspect I know the answers that I'll get).
"Known" seem like rather a strong statement. It should probably be "known by people who don't actually use these models, have no actual formal experience in climate science (or science in general) and tend to be rather biased". Also, "models upon models upon models" does seem to be rather dismissive of the value of models. Maybe someone who thinks this should get out more and look at some other science areas. Models tend to play quite big role. In fact, without models of one kind or another, it's pretty hard to understand much about whatever is being studied. In a sense, this is how science works. Collect some data, analyse the data (which can sometimes also require a model), understand the data (which, typically requires some sort of model).
Of course, if I've misunderstood what's being suggested by this post, feel free to clarify.
Mr Physics - please read here : http://climateaudit.org/2010/06/22/kellys-comments/
"(i) I take real exception to having simulation runs described as experiments (without at least the qualification of ‘computer’ experiments). It does a disservice to centuries of real experimentation and allows simulations output to be considered as real data. This last is a very serious matter, as it can lead to the idea that real ‘real data’ might be wrong simply because it disagrees with the models! That is turning centuries of science on its head."
Everyone drop what you are doing and pay attention to "And Then There's Physics."
He must be right because of his internet moniker.
Andrew
Mr Physics: Some of us are also physicists and know what a validated model looks like and what it can be used for.
John de Melle:
I assume it means they can't exclude the possibility of anthropogenic growth of glaciers?
"no need this question as I suspect I know the answers that I'll get"
Troll too dumb to troll
As others have already spotted, they've 'chosen' to completely omit Antarctica! That's only c90% of all global land ice right there. Quite unbelievable.
Bad Andrew,
Glad you're finally working that out :-)
But, more seriously, it's not about being right or wrong, but surely people here would like to construct a better argument than "models upon models upon models". Something with a bit more depth and a bit of thought. Maybe not quite as dismissive of anything which your reputation might automatically lead people like me to think that you disagree with just because it's inconvenient. Wouldn't you hate people to think that your judgement of a piece of work is based largely on your biases, rather than on a thoughtful analysis of the actual work?
ATTP,
Oh I disagree. It is about right and wrong. And my pet peeve is internet commenters who give themselves names that self-endow with some magical authority or knowledge or make a childish appeal to sciency language.
You probably understand what I'm saying. ;)
Andrew
Bad Andrew,
Oh, I do. However, I don't care, You probably understand why ;-)
"You probably understand why ;-)"
I certainly do. :)
Andrew
Anders
I set out why the GCMs are unsuitable for drawing the conclusions that this study did. You chose not to address these arguments, but selected a few words out of context and attacked those. I am reaching the conclusion, based on your behaviour today, both here and on Twitter that your intention is to waste everyone's time. This will not work because the next time I will simply block you.
It's your choice.
You have yet to say anything that would lead the casual observer to discern such.
Am I understanding that abstract right?
""Here we show that only 25 ± 35% of the global glacier mass loss during the period from 1851 to 2010 is attributable to anthropogenic causes."
To mean between -10% and +60% of global glacier mass loss is attributable to man? Or do they mean 25 of some unexpressed unit + or minus 35%.(So between 16 and 34 of that unit)
Likewise for:
"... the anthropogenic fraction of global glacier mass loss during that period has increased to 69 ± 24%."
To mean between 45% and 93%? Or do they mean 69 plus or minus 24% of 69?
If it is the former in both cases those are terrible margins of error.
"they weren't really able to precisely predict the pause." !!
They didn't get anywhere near predicting it. The Met Office predicted 0.3C rise from 2004-14.
This (snip) is one of I think two people who I have blocked on twitter, for repeated (snip), while claiming to be a scientist, while showing none of the characteristics required in science, and claiming to be trying to keep the discussion civil.
I have just looked at this numpty's blog. Yet again, in his latest post, he is commenting on something he hasn't read!
@Gareth
About 50% of chickens are little
Technically, there has been no statistically significant human contribution to glacier melt since 1850, as the margin of error is larger than the value (25 ± 35%).
There is a significant contribution since 1991, but I wonder why they only went to 2010, when the glacier data was updated in Aug 2013....
Anders
Having misrepresented my case in your previous comment, you apologise and then proceed in your very next one to misrepresent it again, saying "[I wish] hat you didn't simply dismiss something because it uses models". As I have pointed out, my case is that the models are inadequate because of their validation failures both at a global level and subglobal levels.
I have deleted your comment. You can resubmit if you would like to try again without misrepresenting me.
[This was in response to a deleted comment. I have amended it a bit to make it a more general comment about climate models]
All the models can do is produce model output that is consistent with the programming. It requires a decision beforehand about what to attribute to natural variation and what to attribute to man, based on the observation record. If you then remove the man made influences from the model and get a different result it does not prove that man made the difference, only that your computer program requires natural variability and man made influences to get anywhere close to matching the observation record.
You could alternatively create a model that fudges everything as natural variability. This would allow you to re-run the model adding in anthropogenic factors (which would have no effect) and insist your model proves that man has had no effect on the climate. It would be no more wrong than what climatologists currently do by removing anthropogenic factors from models designed to take them into account.
Climate models seem to me to be a terrible way of trying to investigate the hypothesis behind man made climate change.
"Collect some data"
As opposed to making it up with a 'model' based on your own assumptions which has so far proved to be completely inaccurate?
Bishop,
Not to worry, but thanks for offering.
Historical context suggests the late 20th Century recession of glaciers is just a continuation of the long slow thaw from the end of the LIA:
Glacier Bay (Alaska) Glacial terminus, 1780 to present.
Jakobshavn Glacier (west coast of Greenland) likewise: most of the Jakobshavn-glaciers retreat occurred when co2 was less than 310-ppm
Chylek et al, 2006 is also worth reading for historical context - they look at temperature data rather than use models and conclude that 1995-2005 'warm period' in Greenland was just a mild decade, and nothing unusual or unprecedented. Maybe linked to the PDO, or just natural variation, but nothing to be worried about.
Greenland warming of 1920–1930 and 1995–2005.
And Then There's Physics' website says "Trying to keep the discussion civil". The current article then says how he called Rupert Darwall a prat. That says all you need to know about him. Let's hope he doesn't turn up here any more with his cr@p.
Philip
Yes, when he admitted that he had been trying to wind me up on Twitter, I did wonder about "trying to keep the discussion civil". But not as much as I wondered when he called me a rude name on Twitter because I blocked him.
I'm more than happy to acknowledge my lapses in civility, as they do sometimes happen. I have no memory of calling you a rude name though, and wasn't even aware that you'd blocked me. Maybe you could substantiate your statement.
Why deleted Anders' comment? Now we can't see anymore what fool he/she makes of him/herself....