Arctic ice melt could trigger uncontrollable climate change at global level

[lynnvinc]

I only saw what was in the video. However, I have heard that there is some ice shelves there in Antarctica (I don’t know where or which ones) that are holding the ice on land back from sliding into the ocean. Maybe this was one of those. I look into it later…

Okay, here it is: Saw the video again to find our which glacier – Pine Island Glacier (PIG in the map below) on West Antarctica. Then looked up the 2009 post on it I had read at RealClimate.org – Is Pine Island Glacier the Weak Underbelly of the West Antarctic Ice Sheet? at realclimate.org/index.php/archives/2009/11/is-pine-island-glacier-the-weak-underbelly-of-the-west-antarctic-ice-sheet/

Apparently the danger of more rapid glacier disintegration was predicted back in 1978 by John Mercer, who predicted major deglaciation of the West Antarctic Ice Sheet (WAIS) could be in progress within 50 years, which would be by 2028. Apparently that prediction was forgotten until more recent times.

From the RealClimate guest post by Mauri Pelto: “This conclusion was based on the fact that the WAIS margin was ringed with stabilizing ice shelves, and that much of the ice sheet is grounded below sea level. The loss of ice shelves — Mercer proposed — would allow the ice sheet to thin, grounding lines to retreat and the ice sheet to disintegrate via calving. This is a much faster means of losing mass than melting in place.”

 

[vz71]

So the proof is a video you watched that does not specify what you describe?

Sounds to me another exaggeration.

I am sure you mean well, but misinformation is not the way to do it.

 

[lynnvinc]

So the proof is a video you watched that does not specify what you describe?

Sounds to me another exaggeration.

I am sure you mean well, but misinformation is not the way to do it.

AGAIN, as posted in #151 at forums.catholic-questions.org/showpost.php?p=14487424&postcount=510 … (please read more carefully this time):

Okay, here it is: Saw the video again to find our which glacier – Pine Island Glacier (PIG in the map below) on West Antarctica. Then looked up the 2009 post on it I had read at RealClimate.org – Is Pine Island Glacier the Weak Underbelly of the West Antarctic Ice Sheet? at realclimate.org/index.php/archives/2009/11/is-pine-island-glacier-the-weak-underbelly-of-the-west-antarctic-ice-sheet/

Apparently the danger of more rapid glacier disintegration was predicted back in 1978 by John Mercer, who predicted major deglaciation of the West Antarctic Ice Sheet (WAIS) could be in progress within 50 years, which would be by 2028. Apparently that prediction was forgotten until more recent times.

From the RealClimate guest post by Mauri Pelto: “This conclusion was based on the fact that the WAIS margin was ringed with stabilizing ice shelves, and that much of the ice sheet is grounded below sea level. The loss of ice shelves — Mercer proposed — would allow the ice sheet to thin, grounding lines to retreat and the ice sheet to disintegrate via calving. This is a much faster means of losing mass than melting in place.”

 

[Theo520]

Up until the floating ice broke off, it was solidly connected to parts of the mainland ice that are not part of the glacier and were not moving. This connection to land makes it possible to exert a force on the glacier.

Yes, you could line up a thousand tug boats and try push the ice back up on land, but the water itself is providing no such force. As I said, water is a lubricant and provides no friction to resist the ice flow.

 

[LeafByNiggle]

Yes, you could line up a thousand tug boats and try push the ice back up on land, but the water itself is providing no such force. As I said, water is a lubricant and provides no friction to resist the ice flow.

I know. I’m not relying on the water to do that. I’m relying on ability of solid ice to form a mechanical link to the land. The fact that a portion of that solid ice is being supported by water does not prevent that from happening.

 

[Ender]

Up until the floating ice broke off, it was solidly connected to parts of the mainland ice that are not part of the glacier and were not moving. This connection to land makes it possible to exert a force on the glacier.

The ice that broke off was part of the Pine Island glacier, which by definition…moves.*A glacier is a persistent body of dense ice that is constantly moving under its own weight
*What force does the land exert on the glacier except as resistance to the weight of the glacier itself? It is gravity that moves the glacier, and that force is actually lessened now that part of the unsupported section of the glacier has been removed.

Ender

 

[LeafByNiggle]

The ice that broke off was part of the Pine Island glacier, which by definition…moves.*A glacier is a persistent body of dense ice that is constantly moving under its own weight
*What force does the land exert on the glacier except as resistance to the weight of the glacier itself? It is gravity that moves the glacier, and that force is actually lessened now that part of the unsupported section of the glacier has been removed.

Ender

You are making assumptions about the geography of the area. The effect of gravity on moving ice toward the sea depends on the slope of the ground. Ice that is floating does not “pull” the glacier in after it, if that is the theory you are proposing. But Lynn’s posting addressed this very well:

*From the RealClimate guest post by Mauri Pelto: “This conclusion was based on the fact that the WAIS margin was ringed with stabilizing ice shelves, and that much of the ice sheet is grounded below sea level. The loss of ice shelves — Mercer proposed — would allow the ice sheet to thin, grounding lines to retreat and the ice sheet to disintegrate via calving. This is a much faster means of losing mass than melting in place.”
*

 

[lynnvinc]

The ice that broke off was part of the Pine Island glacier, which by definition…moves.*A glacier is a persistent body of dense ice that is constantly moving under its own weight
*What force does the land exert on the glacier except as resistance to the weight of the glacier itself? It is gravity that moves the glacier, and that force is actually lessened now that part of the unsupported section of the glacier has been removed.

Ender

That’s true, but it has to do with the speed and net loss or gain. A stable glacier will move slowly – at glacial speed . There will be enough snowfall to offset any losses through melting and/or calving.

In this case, global warming impacts and knock-on effects are causing net loss, and by this calving (mechanical r/t melting in place) mechanism, a much faster loss.

Now if what you are referring to is the rebound effect (bedrock uplift) due to less weight on the land due to this net loss, I’ve read about that and how it actually reduces sea level vis-à-vis the land (the land moves upward a bit), so that not as much of the glacier is on land beneath sea level. It is a negative feedback stabilizing influence on the glacier. However, under our current high GHG emissions situation (with positive feedbacks from nature) the projection is that won’t be enough to stabilize the glaciers or reverse net loss from calving. See nature.com/articles/ncomms9798

Sensitivity analyses show that the stabilization tends to be greatest for lower emission scenarios and Earth models characterized by a thin elastic lithosphere and low-viscosity upper mantle, as is the case for West Antarctica.

Here are some resources for those interested:

scholar.google.co.in/scholar?as_q=pine+island+glacier&as_epq=&as_oq=&as_eq=&as_occt=any&as_sauthors=&as_publication=&as_ylo=2015&as_yhi=2017&btnG=&hl=en&as_sdt=0%2C44

scholar.google.co.in/scholar?q=antarctica+author%3Aian+author%3AHowat&btnG=&hl=en&as_sdt=0%2C44&as_ylo=2010&as_yhi=2017

scholar.google.co.in/scholar?q=antarctic+author%3ADavid+author%3AHolland&hl=en&as_sdt=0%2C44&as_ylo=2010&as_yhi=2017&oq=

 

[Theo520]

CLIMATE MODELS for the laymen

This paper is a good overview of our climate models and their risk

Executive Summary
There is considerable debate over the fidelity and utility of global climate models
(GCMs). This debate occurs within the community of climate scientists, who disagree about the amount of weight to give to climate models relative to observational analyses. GCM outputs are also used by economists, regulatory agencies and policy makers, so GCMs have received considerable scrutiny from a broader community of scientists, engineers, software experts, and philosophers of science. This report attempts to describe the debate surrounding GCMs to an educated but nontechnical audience.

Key summary points

• GCMs have not been subject to the rigorous verification and validation that is the norm for engineering and regulatory science.
• There are valid concerns about a fundamental lack of predictability in the complex nonlinear climate system.
• There are numerous arguments supporting the conclusion that climate models are not fit for the purpose of identifying with high confidence the proportion of the 20th century warming that was human-caused as opposed to natural.
• There is growing evidence that climate models predict too much warming from increased atmospheric carbon dioxide.
• The climate model simulation results for the 21st century reported by the Intergovernmental Panel on Climate Change (IPCC) do not include key elements of climate variability, and hence are not useful as projections for how the 21st century climate will actually evolve.

Climate models are useful tools for conducting scientific research to understand the climate system. However, the above points support the conclusion that current GCMs are not fit for the purpose of attributing the causes of 20th century warming or for predicting global or regional climate change on timescales of decades to centuries, with any high level of confidence. By extension, GCMs are not fit for the purpose of justifying political policies to fundamentally alter world social, economic and energy systems. It is this application of climate model results that fuels the vociferousness of the debate surrounding climate models.

 

[lynnvinc]

CLIMATE MODELS for the laymen

This paper is a good overview of our climate models and their risk

Executive Summary
There is considerable debate over the fidelity and utility of global climate models
(GCMs). This debate occurs within the community of climate scientists, who disagree about the amount of weight to give to climate models relative to observational analyses. GCM outputs are also used by economists, regulatory agencies and policy makers, so GCMs have received considerable scrutiny from a broader community of scientists, engineers, software experts, and philosophers of science. This report attempts to describe the debate surrounding GCMs to an educated but nontechnical audience.

Key summary points

• GCMs have not been subject to the rigorous verification and validation that is the norm for engineering and regulatory science.
• There are valid concerns about a fundamental lack of predictability in the complex nonlinear climate system.
• There are numerous arguments supporting the conclusion that climate models are not fit for the purpose of identifying with high confidence the proportion of the 20th century warming that was human-caused as opposed to natural.
• There is growing evidence that climate models predict too much warming from increased atmospheric carbon dioxide.
• The climate model simulation results for the 21st century reported by the Intergovernmental Panel on Climate Change (IPCC) do not include key elements of climate variability, and hence are not useful as projections for how the 21st century climate will actually evolve.

Climate models are useful tools for conducting scientific research to understand the climate system. However, the above points support the conclusion that current GCMs are not fit for the purpose of attributing the causes of 20th century warming or for predicting global or regional climate change on timescales of decades to centuries, with any high level of confidence. By extension, GCMs are not fit for the purpose of justifying political policies to fundamentally alter world social, economic and energy systems. It is this application of climate model results that fuels the vociferousness of the debate surrounding climate models.

That’s sort of weird now that the observed data is trending a bit higher than model predictions.

Which brings me to my main complaint about Curry – the “low margin of error” fallacy.

She has over-emphasized the low margin of errors (maybe even exaggerated these lower) in climate predictions, temps & sensitivity – that’s not quite as bad as flat out saying there’s no warming, as some in the denialist industry do, or that it’s not caused by GHG emissions, claiming it will drop back down to pre-1980 levels no matter what our GHG emissions.

I asked on her blog one time – what if the actual situation turns out to be on the high end of the margin of error? She gave some rude answer.

As a Christian we are called to virtue, which includes prudence. Or, hope for the best, expect the worst. That is we need to err on the side of expecting the high end of the margin of error, or that CC could end up even worse than we expect.

And we need to overcome our psychological blockages that doing something about CC will greatly harm our pocketbooks (who we think we are, the measure by which many us judge ourselves and fear others judge us).

We need to ask, “What would Jesus do?”

Since he didn’t have a car, I guess getting an EV, hypermiling, turning off engine in drive-thrus, wouldn’t have much meaning for someone who walked (or rode a donkey) everywhere he went. Maybe running multiple errands, moving closer to work might. Like doing the carpentry at home. (Eco in “economy” and “ecology” means “home.”)

But we don’t need to retreat back to the lifestyle of the Holy Family. We can do a lot to reduce our GHGs in ways that do not harm us or even our pocketbook-self-image.

Be not afraid, Jesus is with us always.

 

[Theo520]

Lynn,

• evidence please that observed is higher than predictions. FYI, the one year jump from el nino doesn’t qualify as a trend.
• please support your claim of Curry’s “low margin of error” fallacy, used in this paper. Margin of error isn’t even a phrase used in the paper. Are you deflecting?

 

[lynnvinc]

Lynn,

• evidence please that observed is higher than predictions. FYI, the one year jump from el nino doesn’t qualify as a trend.

Are you talking about the 1998 super- el nino year?

• please support your claim of Curry’s “low margin of error” fallacy, used in this paper. Margin of error isn’t even a phrase used in the paper. Are you deflecting?

I’m familiar with her arguments and she has been saying for many years that scientists don’t emphasize their margin of errors or uncertainty enough.

And she does indeed mention “uncertainties” 17 times in her paper. It is her main argument. Note that uncertainty for her it means CC could be much less a problem or at the low end, while for me (a Girl Scout, taught to “be prepared”) it means it could be much worse than the scientists expect or at the high end):

• p.4 - Uncertainties in GCMs arise from uncertainty in model structure, model parameters and parameterisations, and initial conditions.
• p.5 - There has been insufficient exploration of GCM uncertainties.
• p.6-7- In fact, it seems that uncertainty about value of ECS has increased since the 2007 Fourth Assessment.The bottom of the ‘likely’ range has been lowered from 2 to 1.5◦C in the 2013 Fifth Assessment Report, whereas the Fourth Assessment Report stated that ECS is very unlikely to be less than 1.5◦C…Other recent papers also find comparably low values of ECS and the latest research suggests even lower values. [Note how she is fixated on the low end.]]
• …and several other mentions of uncertainty.

If you think about whether to focus on the high end or low end of the uncertainties, we do spend money and buy home insurance thinking it possible a fire might burn it down or some other catastrophe might happen. So it is not unheard of for us risk-taking Americans to take precautions by expecting, preparing for, and striving to mitigate the worst (looking at the high end of the ME or uncertainty), while hoping for the best (the low end of uncertainty - or no problems).

However, unlike shelling out good money for insurance we can reduce GHGs at savings or no cost down more than 60%, so her argument that mitigating CC is costly (here she looks at the high end of uncertainty) doesn’t hold water either.

 

[Theo520]

Are you talking about the 1998 super- el nino year? :

I’m asking you to support your claim, stop deflecting
lynnvinc: “the observed data is trending a bit higher than model predictions”

I’m familiar with her arguments and she has been saying for many years that scientists don’t emphasize their margin of errors or uncertainty enough.

And she does indeed mention “uncertainties” 17 times in her paper. It is her main argument. Note that uncertainty for her it means CC could be much less a problem or at the low end, while for me (a Girl Scout, taught to “be prepared”) it means it could be much worse than the scientists expect or at the high end):

• p.4 - Uncertainties in GCMs arise from uncertainty in model structure, model parameters and parameterisations, and initial conditions.
• p.5 - There has been insufficient exploration of GCM uncertainties.
• p.6-7- In fact, it seems that uncertainty about value of ECS has increased since the 2007 Fourth Assessment.The bottom of the ‘likely’ range has been lowered from 2 to 1.5◦C in the 2013 Fifth Assessment Report, whereas the Fourth Assessment Report stated that ECS is very unlikely to be less than 1.5◦C…Other recent papers also find comparably low values of ECS and the latest research suggests even lower values. [Note how she is fixated on the low end.]]
• …and several other mentions of uncertainty.

If you think about whether to focus on the high end or low end of the uncertainties, we do spend money and buy home insurance thinking it possible a fire might burn it down or some other catastrophe might happen. So it is not unheard of for us risk-taking Americans to take precautions by expecting, preparing for, and striving to mitigate the worst (looking at the high end of the ME or uncertainty), while hoping for the best (the low end of uncertainty - or no problems).

However, unlike shelling out good money for insurance we can reduce GHGs at savings or no cost down more than 60%, so her argument that mitigating CC is costly (here she looks at the high end of uncertainty) doesn’t hold water either.

Precision matters when discussing science.

She obviously discusses the low end of model uncertainties because that is where the measurement data resides, not the high end where alarmists spend their time.

We should not plan for high end uncertainties for models that are demonstrated unreliable, that predict overarming. Your approach is to ask people in the mountains to buy flood insurance.

 

[lynnvinc]

I’m asking you to support your claim, stop deflecting
lynnvinc: “the observed data is trending a bit higher than model predictions”…

I can’t find the chart now, but on it I saw that 2016 was slightly higher than the projection, but within the uncertainty range.

Here is a link to the NASA data & graph up thru 2016, which has 2016 .98C above and 2015 .86C above: data.giss.nasa.gov/gistemp/graphs/

Here’s the graph to 2016:

(Please Note: This uploaded content is no longer available.)

And below are the observations (looks like up to about 2013) & projections. You can eyeball the .98 mark on the vertical axis and the 2016 year (between 2010 and 2020) on the horizontal and see where they meet…

(Please Note: This uploaded content is no longer available.)

 

[lynnvinc]

…She obviously discusses the low end of model uncertainties because that is where the measurement data resides, not the high end where alarmists spend their time.

We should not plan for high end uncertainties for models that are demonstrated unreliable, that predict overarming. Your approach is to ask people in the mountains to buy flood insurance.

I beg to differ. Not on the current observations (which have been in general a bit lower than projected, but are now on par, slightly above some of the projections), but what is projected into the future.

I’ve asked the CC computer modelers and they say they do NOT include positive feedbacks of GHG releases from melting permafrost and ocean methane hydrates. Nor does it take into account the diminishing albedo effect (reflection) from snow and ice cover loss, making the earth and water absorb more heat. The problem is these cannot be quantified accurately enough to be added into the models – but we do know about them, and that they contributed greatly to super-warming events in the past, like the PETM great warming and extinction event. We also know that this “methane shotgun” is more fully loaded this time around, that there are massive amounts of GHGs in those frozen states.

Currently some is being released as melting is going on from what we have caused so far. This is just the beginning of something that could go on until nearly all the ice & snow is melted and nearly all the methane is released in positive feedback fashion of melting causing GHG release, causing greater warming, causing greater melting, causing greater warming and so on.

So I’m afraid that those computer models grossly underestimate the warming that will be happening once these positive feedbacks kick in more strongly.

Climate science is very reticent and conservative in its claims and projections.

 

[lynnvinc]

…FYI, the one year jump from el nino doesn’t qualify as a trend…

So let’s look at the climate graph controlling for el nino, la nina, and neutral years…And this only goes up to 2011, so it doesn’t even include the 2016 el nino year, but you can eyeball it in close to 1C above, which is “off the chart” but pretty much where that red el nino line is pointing.

http://www.skepticalscience.com/pics/GISTEMPENSO.gif

 

[Theo520]

Lynn, your first chart provided no comparison to model projections, so it’s useless in supporting your point.

Here is the IPCC sourced chart that was included in the paper, clearly showing the actual and updated mean projections are residing below the mean of the model projections.

Yes, the models run HOT. Policy that assumes temps at the upper extreme is highly inappropriate.

(Please Note: This uploaded content is no longer available.)

 

[lynnvinc]

Lynn, your first chart provided no comparison to model projections, so it’s useless in supporting your point.

Here is the IPCC sourced chart that was included in the paper, clearly showing the actual and updated mean projections are residing below the mean of the model projections.

Yes, the models run HOT. Policy that assumes temps at the upper extreme is highly inappropriate.

https://curryja.files.wordpress.com/2016/11/slide6.png

That chart doesn’t seem to include the most recent 2016 global average temp, which is about 1C (.98C). So you can also use your graph and run your vision from the 1C mark on the y-axis across to the year 2016 (which is 60% of the way between 2010 and 2020), and see that it is on the high end of the confidence interval (the top gray line), if not above it.

Sort of proves my point.

But, of course, one or two years does not climate science make, so we need to go back decades and look at the trend. Now if that general trend is a bit lower than computer models projected (of course more recent models project more accurately than those that are 30 years old) then that doesn’t disprove global warming, only that the projections for these past some-odd year were running a bit high FOR NOW. Such projections may well be running a bit low in years to come.

But there is still GW happening, and at most a slower warming just means serious harms happening somewhat later.