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« The numbers game | Main | Is Hot Topic wrong about this too? »

Comments

CM

Um, nowhere in the Hansen quote you've provided does he even mention sea level rise.

Are there zero studies supporting the theory that "meltwater lubricates the base of the ice sheet, accelerating the discharge of giant icebergs to the ocean"?

CM

The next part after your quote is:

"Another process, probably even more effective than surface melt, is melting of ice shelves by warmer ocean
water."

http://www.timesonline.co.uk/tol/news/environment/article6908357.ece

Jim done put that there.

Probably even more effective he says.

Ian Wishart

The backstory, Craig, is that Jim shouldn't have made a big deal of it at all. Spectacular, yes. Meaningful, no.

And whilst he is correct that warm oceans licking the edges of ice shelves are far more significant, these are due to ocean current changes forced by solar, not CO2.

Ian Wishart

I take it, by the way, you've now read his speech and seen the entire context leading up to this was about sea level rise of several metres this century.

I demolished this particular line of reasoning in Air Con, and am happy to report the book's conclusions are more in line with the 30cm a century estimate of the IPCC than they are with mad Jim's.

CM

Ian, why the need to misquote? You've provided three sentences together and specifically stated they are about that one photo. When in fact only the first sentence is under that photo, with the other two under a different photo.

>>>>The backstory, Craig, is that Jim shouldn't have made a big deal of it at all. Spectacular, yes. Meaningful, no.<<<<

I don't see how he's made a 'big deal of it'. Sea level rise gets a couple of paragraphs at the end of the fourth page, in an eighteen page document.

>>>>And whilst he is correct that warm oceans licking the edges of ice shelves are far more significant, these are due to ocean current changes forced by solar, not CO2.<<<<

If he’s correct then it’s not a lie is it. And by not mentioning his qualifier you’ve clearly misrepresented him in order to fabricate your ‘lie’. That’s dishonest. And you missed his next sentence right after your quote too, where he said specifically pointed out that meltwater lubricating the base of the ice sheet is only “one of the processes causing ice loss from Greenland and Antarctica to increase”.

I presume this isn’t just you relying on the controversial Scafetta methodology (with respect to solar versus C02)?

>>>>I take it, by the way, you've now read his speech and seen the entire context leading up to this was about sea level rise of several metres this century.<<<<

Yes I’ve read the whole thing. Again, you are being dishonest. Only a very small part of it is about sea level rise.

>>>>I demolished this particular line of reasoning in Air Con, and am happy to report the book's conclusions are more in line with the 30cm a century estimate of the IPCC than they are with mad Jim's.<<<<

The IPCC’s estimates were between 0.18cm and 0.59cm but that was far from the full story.
See: http://www.realclimate.org/index.php/archives/2007/03/the-ipcc-sea-level-numbers/

I’m not sure that you’ve accurately represented that University of Washington/Woods Hole Oceanographic Institution studies either.

“A two-pronged study published online this week in Science has confirmed that meltwater reaches the base of the Greenland ice sheet and does indeed speed the ice’s seaward flow.”
http://sciencemag.org/cgi/content/summary/320/5874/301

“But while surface meltwater plays an inconsequential role in the movement of outlet glaciers, meltwater is responsible for 50 to 100 percent of the summer speed up for the large stretches near the edge of the ice sheet where there are no major outlet glaciers, a finding consistent with, but somewhat larger than, earlier observations.”
http://uwnews.org/article.asp?articleID=41159

So the speedups from meltwater in summer are actually LARGER than we thought. Is that in your book?

In his speech Hansen talks about these ice shelves and his picture you failed to mention (above the second two sentences you quoted) is of an ice stream.

“What Joughin, Das and their co-authors confirm is that iceflow speed up with meltwater is a widespread occurrence, not restricted to the one site where previously observed. But, they also show that the really fast-moving ice doesn't speed up very much with this. So we can expect the ice sheet in a warming world to shrink somewhat faster than previously expected, but this mechanism will not cause greatly faster shrinkage," says Richard Alley, professor of geosciences at Pennsylvania State University, who is not connected with the papers.”

http://uwnews.org/article.asp?articleID=41159

This is not how you have summarised the findings.

The studies were also looking at a single lake of meltwater.

It seems that it’s you making a big deal out of this, rather than Hansen.
Interestingly, the Utrecht University study you also mention does not show that the melt is decreasing - to the contrary it shows a small increase in ablation, which is fully consistent with IPCC predictions concerning melt of the ice sheet.

CM

Study: Greenland ice sheet larger contributor to sea-level rise

The Greenland ice sheet is melting faster than expected according to a new study led by a University of Alaska Fairbanks researcher and published in the journal Hydrological Processes.
Study results indicate that the ice sheet may be responsible for nearly 25 percent of global sea rise in the past 13 years. The study also shows that seas now are rising by more than 3 millimeters a year--more than 50 percent faster than the average for the 20th century.

UAF researcher Sebastian H. Mernild and colleagues from the United States, United Kingdom and Denmark discovered that from 1995 to 2007, overall precipitation on the ice sheet decreased while surface ablation--the combination of evaporation, melting and calving of the ice sheet--increased. According to Mernild’s new data, since 1995 the ice sheet lost an average of 265 cubic kilometers per year, which has contributed to about 0.7 millimeters per year in global sea level rise. These figures do not include thermal expansion--the expansion of the ice volume in response to heat--so the contribution could be up to twice that.

The Greenland ice sheet has been of considerable interest to researchers over the last few years as one of the major indicators of climate change. In late 2000/early 2001 and in 2007, major glacier calving events sent up to 44 square miles of ice into the sea at a time. Researchers are studying these major events as well as the less dramatic ongoing melting of the ice sheet through runoff and surface processes.

Ice melt from a warming Arctic has two major effects on the ocean. First, increased water contributes to global sea-level rise, which in turn affects coastlines across the globe. Second, fresh water from melting ice changes the salinity of the world’s oceans, which can affect ocean ecosystems and deep water mixing.

“Increasing sea level rise will be a problem in the future for people living in coastal regions around the globe,” said Mernild. “Even a small sea level rise can be a problem for these communities. It is our hope that this research can provide people with accurate information needed to plan for protecting people and communities.”

http://www.uaf.edu/news/a_news/20090611122526.html

Ian Wishart

“Ian, why the need to misquote? You've provided three sentences together and specifically stated they are about that one photo. When in fact only the first sentence is under that photo, with the other two under a different photo.”

Craig, with respect did you pass School C English comprehension? The photo was an example of meltwater going through a hole, which addressed the point Hansen was making and that I was rebutting.

“Sea level rise gets a couple of paragraphs at the end of the fourth page, in an eighteen page document.”

The points he was making were part of a major speech, the individual threads of which he wove together as part of his grand narrative. The first part of his speech deals with ice sheet melt and subsequent sea level increase. Sea levels are explicitly discussed for the first time on page 2, not page 4.

“If he’s correct then it’s not a lie is it. And by not mentioning his qualifier you’ve clearly misrepresented him in order to fabricate your ‘lie’. That’s dishonest."

His next point about warmer oceans is irrelevant to the discussion about surface meltwater lubricating ice sheets and sending them scampering into the sea. His first claim has been soundly debunked. The water that melted on the surface re-froze underneath. Net contribution to sea level rise? Near enough to zilch.

"And you missed his next sentence right after your quote too, where he said specifically pointed out that meltwater lubricating the base of the ice sheet is only “one of the processes causing ice loss from Greenland and Antarctica to increase”.“

But it’s not really causing a major increase in ice loss at all, is it. So don’t be disingenuous.

“The IPCC’s estimates were between 0.18cm and 0.59cm but that was far from the full story. See: http://www.realclimate.org/index.php/archives/2007/03/the-ipcc-sea-level-numbers/”

Quoting RealClimate? Don’t make me laugh.

Air Con extensively looks at the science up to April 09, and with sea levels rising only between 2mm and 3mm a year, they will have to accelerate rapidly to hit the wild predictions of twits like Hansen who was picking five metres by 2100.

" I’m not sure that you’ve accurately represented that University of Washington/Woods Hole Oceanographic Institution studies either. “A two-pronged study published online this week in Science has confirmed that meltwater reaches the base of the Greenland ice sheet and does indeed speed the ice’s seaward flow.” http://sciencemag.org/cgi/content/summary/320/5874/301 “But while surface meltwater plays an inconsequential role in the movement of outlet glaciers, meltwater is responsible for 50 to 100 percent of the summer speed up for the large stretches near the edge of the ice sheet where there are no major outlet glaciers, a finding consistent with, but somewhat larger than, earlier observations.” http://uwnews.org/article.asp?articleID=41159 So the speedups from meltwater in summer are actually LARGER than we thought. Is that in your book?"

Again, I covered this in the book (you really should read it before shooting first) and you are missing the point. Pay a little bit more attention to the detail.

The claim is that water disappearing down holes was sending ice sheets and glaciers skating rapidly toward the coast. The glaciers move far faster than ice sheets and pour far more ice into the ocean when they move. The study you and I are both quoting says:

>Outlet glaciers are rapid flows of ice that start in the Greenland Ice Sheet and extend all the way to the ocean, where their fronts break apart in the water as icebergs, a process called calving. While most of the ice sheet moves less than one tenth a mile a year, some outlet glaciers gallop along at 7.5 miles a year, making outlet glaciers a concern because of their more immediate potential to cause sea level rise.
If surface meltwater lubrication at the intersection of ice and bedrock was playing a major role in speeding up the outlet glaciers, one could imagine how global warming, which would create ever more meltwater at the surface, could cause Greenland's ice to shrink much more rapidly than expected -- even catastrophically. Glacial ice is second only to the oceans as the largest reservoir of water on the planet and 10 percent of the Earth's glacial ice is found in Greenland.<

However, the study found this wasn’t happening. And a 50% increase on ice sheet movement of almost nothing is still, well, almost nothing.

You say:

“In his speech Hansen talks about these ice shelves and his picture you failed to mention (above the second two sentences you quoted) is of an ice stream.”

That’s because I wasn’t discussing ice streams, for reasons already laid out ad nauseum. Sigh.
The Utrecht study’s findings I concentrated on related to whether meltwater going down holes was causing an acceleration of galloping glaciers. They found it wasn’t. Their findings in regard to melt are hardly surprising, as I make the point in the book that Greenland had been enjoying a decade of melting.

However, if I had wanted to raise overall melt rates, then I would have quoted this from a paper in Science this year:

“Ice loss in Greenland has had some climatologists speculating that global warming might have brought on a scary new regime of wildly heightened ice loss and an ever faster rise in sea level. But glaciologists reported at the American Geophysical Union meeting that Greenland ice’s Armageddon has come to an end.”293

“An increasingly warmer climate will no doubt eat away at the Greenland ice sheet for centuries, glaciologists say, but no one should be extrapolating the ice’s recent wild behaviour into the future.”

In other words, all that Greenland melt alarm we’ve been subjected to turns out to have been nothing more than a passing warm spell, making claims of a one metre sea level hike this century even more impossible to meet than they already were.
No danger then of Greenland’s icecap inundating “Bangladesh, Florida, the Maldives and the Netherlands”, with the Thames estuary thrown in for good measure?

“The speed-up [of Greenland ice melt] has stopped across the region,” confirmed the UK Met Office Hadley Centre’s Vicky Pope in February this year.294
“Recent headlines have proclaimed that Arctic summer sea ice has decreased so much in the past few years that it has reached a tipping point and will disappear very quickly. The truth is that there is little evidence to support this. Indeed, the record-breaking losses in the past couple of years could easily be due to natural fluctuations in the weather, [my emphasis] with summer sea ice increasing again over the next few years.”

And so it did.

Hansen is a fool who continues to inflate the alarmism (much like Hot Topic), in the face of repeated warnings from his colleagues.

Ian Wishart

In regard to your latest study meanwhile, it has taken too long to go to press. The study period ended in 2007, and by the start of 2009, as reported above, Greenland melt had slowed right down.

AcidComments


Of interest:

Multiple Factors Caused 100% of Arctic Warming: Ozone, Soot, Ocean Cycles, Solar & Wind Circulations - Peer-Reviewed Studies Ignore CO2
Read here, here, here, here, and here. For all the CO2-causes-warming alarmist hysteria emanating from bureaucrats, politicians, the MSM and Hollywood celebrities about the Arctic, one would think climate researchers would have published numerous studies directly linking human-CO2 to Arctic warming/melting. Instead,.....
peer-reviewed studies of recent past have found all sorts of warming influences impacting the Arctic, just none of them linking human CO2 to being the actual cause.

http://www.c3headlines.com/2009/10/multiple-factors-caused-100-of-arctic-warming-ozone-soot-ocean-cycles-solar-wind-circulations---peer-reviewed-studies.html

CM

>>>>Craig, with respect did you pass School C English comprehension? The photo was an example of meltwater going through a hole, which addressed the point Hansen was making and that I was rebutting.<<<<

I did pass School C English thanks. Not sure what school you went to, but English Comprehension wasn’t offered separately.

So you were just being sloppy.

>>>>The points he was making were part of a major speech, the individual threads of which he wove together as part of his grand narrative. The first part of his speech deals with ice sheet melt and subsequent sea level increase. Sea levels are explicitly discussed for the first time on page 2, not page 4.<<<<

Still a very minor part of the overall speech. He introduces the section you are taling about with:
“Let’s look more at processes contributing to ice sheet disintegration.” You seem to be implying that those words mean “Let’s look more at processes contributing to sea level rise”. Which is simply not true.
And not only does he state that it’s ONE of the processes, but he explicitly points out that “probably even more effective” (in terms of ice loss) is the warmer ocean. So he’s got two qualifiers in there. One pointing out that meltwater lubricating the base of the ice sheet is only one process, and the other making it fairly clear that another process is likely to have more effect.
So I don’t see the ‘lie’. I can clearly see your spin though.

And actually if we go back further, to Page 2, he says:

“The mechanism that seems to be most important for disintegration of the great ice sheets that cover Antarctica and Greenland begins with ocean warming. Ocean warming leads to melting
of ice shelves, which are tongues of ice that stretch out into the ocean. The ice shelves buttress the ice sheets, so when ice shelves disappear the more mobile parts of the ice sheet, the ice
streams, can surge into the ocean – thus removal of the ice shelves is somewhat akin to taking the cork out of a bottle – it allows the material behind to flow rapidly. We know from Earth’s history that once ice sheet disintegration is well underway, sea level can rise by several meters per century.”

So basically he’s saying that ocean warming is the “most important” mechanism.
Isn’t that what you’re arguing?

>>>>His next point about warmer oceans is irrelevant to the discussion about surface meltwater lubricating ice sheets and sending them scampering into the sea. His first claim has been soundly debunked. The water that melted on the surface re-froze underneath. Net contribution to sea level rise? Near enough to zilch.<<<<

His first ‘claim’ is that on page 2, as quoted above. The ‘claim’ that you seem to be hung up on concerns meltwater lubricating the base of the ice sheet being a process which leads to iceloss (but that a warmer ocean is probably a more effective process, which he then mentions for a second time). How has that been debunked? Nothing you’ve provided ‘debunks’ that ‘claim’.

You’re also ignoring how he introduces sea level rise at the end of page 4. Are you trying to say that, historically, ice melt did not cause sea level rise?

>>>>But it’s not really causing a major increase in ice loss at all, is it. So don’t be disingenuous.<<<<

Projection. It’s you that’s being disingenuous, by implying he makes a ‘big deal’ by explaining a single process within a few sentences in an 18 page document, even though he states once that it’s only a single process and twice that the most significant process is ocean warming (either side of explaining the lubrication process).

Vieli states: “Essentially, higher air temperatures and warmer seas mean you're going to get more calving in a glacier like the Hellheim Glacier. But as these glaciers retreat inland more, maybe surface melt will become the dominant factor making them lose ice”.
http://planetearth.nerc.ac.uk/news/story.aspx?id=295

CM

>>>>Quoting RealClimate? Don’t make me laugh.<<<<

If that is your attitude (to play the man instead of the ball) then how do you expect anyone to pay attention to anything you post from McIntyre or Watts or Morano?

The piece was pointing out the limitations of the IPCC sea level rise predictions.

>>>>Air Con extensively looks at the science up to April 09, and with sea levels rising only between 2mm and 3mm a year, they will have to accelerate rapidly to hit the wild predictions of twits like Hansen who was picking five metres by 2100.<<<<

It is clear that the paleo-record shows greater than meter/century rises during the deglaciation (MWP 1A), or even in the Holocene (Carlson et al, 2008). Therefore these possibilities cannot be neglected and it would be foolhardy to do so. But to then cherry-pick these possibilities as hard and firm predictions is just silly.
In this speech Hansen says “I find it implausible that the West Antarctic ice sheet could survive this century, if business-as-usual emissions continue. Thus, in such an emission scenario, sea level rise of several meters should be expected this century”.
If that’s what he’s picking now, based on the latest research and increased knowledge, why are you referring to what he might have quoted previously (http://pubs.giss.nasa.gov/docs/2007/2007_Hansen.pdf)?

>>>>Hansen is a fool who continues to inflate the alarmism (much like Hot Topic), in the face of repeated warnings from his colleagues.<<<<

When we look into it though, a lot of it isn’t alarmism at all, it’s just spin to make it seem alarmist. That’s not to say that there isn’t some over-shooting involved, just that claims that it’s all lying are sometimes just silly. You’ve actually got to make a case to support the accusation.

>>>> The claim is that water disappearing down holes was sending ice sheets and glaciers skating rapidly toward the coast. The glaciers move far faster than ice sheets and pour far more ice into the ocean when they move.<<<<

>>>> However, the study found this wasn’t happening.<<<<

http://planetearth.nerc.ac.uk/news/story.aspx?id=295

“Although earlier research has shown that meltwater can find its way to the base of alpine glaciers, nobody has been able to link warmer temperatures to the speed at which land-terminating glaciers in an ice sheet flow.
Shepherd and his team placed three GPS sensors on the surface of the Russell Glacier along the 'line of flow' to monitor the movement of ice during late summer. They also used satellite images to monitor lake formation on the surface of the ice to find out if the glacier moved when water disappeared from these lakes. Shepherd guessed that water from the lakes could be streaming to the base of the glacier and helping it move faster.
After peak melting time - usually around midday - the team found that the speed of ice doubled two hours later, but slowed down 12 hours afterwards once air temperatures had cooled. During late summer, the ice accelerated as the temperature increased. The speed of the glacier was double the winter average.
Accelerating ice
Using a model to estimate the amount of meltwater produced by the glacier, the team found that the amount of daily meltwater matched the acceleration of the ice. The glacier moved the most after water in the lakes had drained. At one site, the ice moved by as much as 250 metres in one year. Land-terminating glaciers move much more slowly than glaciers that reach the sea - so-called outlet glaciers, which travel several kilometres a year.
'Nobody knew that ice sheet glaciers could respond so quickly. Up until now, people thought glaciers didn't react to their environment very quickly at all,' says Shepherd, a glaciologist from the University of Edinburgh's School of Geosciences and leader of the research team.
In a different study, published in Nature Geoscience last week, Andreas Vieli and Faezeh Nick from Durham University found the reasons for rapid ice loss in outlet glaciers.
Whereas the loss of ice in the land-terminating Russell Glacier in Shepherd's study is dominated by surface melt, Vieli unearthed a different mechanism for ice loss in outlet glaciers.
Vieli and his team found that the Hellheim Glacier, in east Greenland, speeds up in response to changes at its calving end - the part of the glacier that juts into the sea.
They wanted to see how different effects on the glacier compared with the ice loss researchers have witnessed. So they used computer models to test how various scenarios affected the glacier.
When they increased meltwater lubrication at the glacier's base, unlike Shepherd's study, the glacier didn't speed up towards the ocean. But when they decreased the stability at the front end of the glacier - such as would happen in a warming climate - ice thinning, acceleration and retreat quickly spread far up the glacier. This exactly mimics what researchers have seen in Greenland.
'Essentially, higher air temperatures and warmer seas mean you're going to get more calving in a glacier like the Hellheim Glacier. But as these glaciers retreat inland more, maybe surface melt will become the dominant factor making them lose ice,' says Vieli.
Vieli is keen to point out that you have to be careful about extrapolating ice loss from just a few years' observations into the future. Researchers are still a long way off predicting how fast sea levels will rise as Greenland's ice sheet disappears. Even so, both of these studies are a step forward in refining the ice aspect of current climate models.”

>>>>However, if I had wanted to raise overall melt rates, then I would have quoted this from a paper in Science this year<<<<

Your quote isn’t from the paper, but from a ‘News Focus’ piece in Science by Kerr.

>>>>In other words, all that Greenland melt alarm we’ve been subjected to turns out to have been nothing more than a passing warm spell, making claims of a one metre sea level hike this century even more impossible to meet than they already were.
No danger then of Greenland’s icecap inundating “Bangladesh, Florida, the Maldives and the Netherlands”, with the Thames estuary thrown in for good measure?<<<<

You’re doing the same thing as you claim the ‘alarmists’ are doing. Making definitive claims based on limited information and understanding.
Vicky Pope, who you then quote, complains about this misrepresentation here (where your quote appears, funnily enough):
http://www.metoffice.gov.uk/corporate/pressoffice/2009/pr20090211.html
“The most recent example of this sequence of claim and counter-claim focused on the Greenland ice sheet. The melting of ice around south-east Greenland accelerated in the early part of this decade, leading to reports that scientists had underestimated the speed of warming in this region. Recent measurements, reported in Science magazine last week, show that the speed-up has stopped across the region. This has been picked up on the climate sceptics’ websites. Again, natural variability has been ignored in order to support a particular point of view, with climate change advocates leaping on the acceleration to further their cause and the climate change sceptics now using the slowing down to their own benefit. Neither group is right and all that is achieved is greater confusion among the public. What is true is that there will always be natural variability in the amount of ice around Greenland and that as our climate continues to warm, the long-term reduction in the ice sheet is inevitable.
“For climate scientists, having to continually rein in extraordinary claims that the latest extreme is all due to climate change is, at best, hugely frustrating and, at worst, enormously distracting. Overplaying natural variations in the weather as climate change is just as much a distortion of the science as underplaying them to claim that climate change has stopped or is not happening. Both undermine the basic facts that the implications of climate change are profound and will be severe if greenhouse gas emissions are not cut drastically and swiftly over the coming decades.
“When climate scientists like me explain to people what we do for a living we are increasingly asked whether we “believe in climate change”. Quite simply it is not a matter of belief. Our concerns about climate change arise from the scientific evidence that humanity’s activities are leading to changes in our climate. The scientific evidence is overwhelming.”

>>>>Hansen is a fool who continues to inflate the alarmism (much like Hot Topic), in the face of repeated warnings from his colleagues.<<<<

That may be so, but it’s no good complaining about people over-egging the pudding (or being selective in what papers they rely on) when you repeatedly do the same thing yourself. If it’s so obvious, then you should be able to demonstrate it in a manner that doesn’t leave you so open to criticism.

CM

>>>>In regard to your latest study meanwhile, it has taken too long to go to press. The study period ended in 2007, and by the start of 2009, as reported above, Greenland melt had slowed right down.<<<<

You've yet to show why the reduction is speed over the last couple of years is meaningful in the long term.
Your implication seems to be that if the temperature doesn’t go up any more, the glaciers will reach a new equilibrium. That might be the case for a year here and there, or even a few years at a time, but the temperature trend is definitely upwards. So it seems like the glaciers would continue to react strongly when there’s a warming. Any assumption that the new, higher temperature is stable is unrealistic at the moment.

CM

Also:

"Our 2009 area change survey of 34 of the widest Greenland marine-terminating glacier outlets from the inland ice sheet is complete. We find a net marine-terminating ice area loss of 109 sq km. The total net cumulative area change from year 2000 (when our survey begins) to 2009 is -990.2 sq. km, a loss equivalent with an area more than 11 times the area of Manhattan Is. (87.5 sq. km) in New York, USA. The marine-terminating ice area change for these glaciers is -106 sq. km per year, the 2009 loss being within 3% of the linear fit. In other words, and as you can see below, the loss rate has been nearly constant."

http://bprc.osu.edu/MODIS/?p=61

CM

>>>>....by the start of 2009, as reported above, Greenland melt had slowed right down.<<<<

"The Greenland ice sheet is losing its mass faster than in previous years and making an increasing contribution to sea level rise, a study has confirmed.

Published in the journal Science, it has also given scientists a clearer view of why the sheet is shrinking.

The team used weather data, satellite readings and models of ice sheet behaviour to analyse the annual loss of 273 thousand million tonnes of ice.

Melting of the entire sheet would raise sea levels globally by about 7m (20ft).

For the period 2000-2008, melting Greenland ice raised sea levels by an average of about 0.46mm per year.

Since 2006, that has increased to 0.75mm per year."

http://news.bbc.co.uk/2/hi/science/nature/8357537.stm

How is 0.75mm per year slower than 0.46mm per year?

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