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Comment on Open thread by AK

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Condemned by <b>one of</b> its original founders. Old news.

Comment on New presentations on sea ice by Mi Cro

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“There were indeed some warm period in those decades, but the sea ice came no where close to the summer lows we’re seeing now.”

And you know this how?

Comment on Evidence of deep ocean cooling? by alpha2actual

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Excellent comment, right on target and much more civil than my thought.

Comment on Open thread by Pierre-Normand

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Rob Ellison wrote: “Molecules diffuse outward into the surrounding air. Intermolecular forces are important in expansion of a real gas – I just said that. In kinetic theory as I just said – ideal gases are assumed with no intermolecular forces. So there is expansion that is due to the kinetic energy of the molecules. They have energy and they bounce around and suddenly they are free to bounce around more and more widely disperse. It is a diffusion process – dW is irrelevant except as a mathematical abstraction – which I think I have said about 10 times.”

You’ve said this 10 times and been wrong 10 times. Notice that in the process of Joule expansion, the molecules *also* are free to bounce around and more widely disperse in the empty space newly opened to them, yet there is exactly zero loss of kinetic energy and zero drop in temperature — because there is no external work done. So, this process isn’t relevant to the case of adiabatic expansion withing a slowly expanding gaseous medium (e.g. more air parcels around) or expanding solid enclosure. The two-way material diffusive flux at the notional boundary is irrelevant to the temperature drop in the middle of the expanding parcel since if there were a thin flexible boundary there (as the foil of a rising weather balloon) then there would be no diffusive flux at all but there would still be the very same temperature drop everywhere within the balloon.

I also granted to you that when the parcel of *real* gas expands, there is *some* (small) part the the reduction in KE of the molecules that is accounted for by the work of inter-molecular forces. It’s this reduction that’s isolated in the artificial Joule-Thompson throttling process. But this is several orders of magnitude smaller than the reduction in KE energy accounted for by the reduction in total internal energy (which you deny occur) that corresponds to dW. Hence, the process that you think mainly accounts for the temperature drop of a rising parcel of air, is negligible compared with the process that you wish to dismiss as a mere mathematical fiction. If your’s were the main process, the dry adiabatic lapse rate (theoretical and measured, e.g. within rising weather balloons) would be very much smaller (about three or four orders of magnitudes according to rough calculation) that the standard textbook result (9.8°C/km) that posits the dW = PdV drop in internal energy.

Comment on New presentations on sea ice by Ragnaar

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Looking at AR5, these seem to be the take away messages:
“Comparing trends from the CCSM4 ensemble to observed trends suggests that internal variability could account for approximately half of the observed 1979–2005 September Arctic sea ice extent loss.”

“In the case of the Arctic we have high confidence in observations since 1979, from models (see Section 9.4.3 and from simulations comparing with and without anthropogenic forcing), and from physical understanding of the dominant processes; taking these three factors together it is
very likely that anthropogenic forcing has contributed to the observed decreases in Arctic sea ice since 1979.”

I can’t find error bars for the first statement. I am left to speculate how to read the word, ‘could’? I see that you’re writing that Curry ended up centering on 50%. I imagine some scientists are on the high end of 85% to 100% anthropogenic forcing. So whatever distribution lies behind their above statement there’s going to be a range of opinions.

The second statement says, yes there has been an anthropogenic forcing. They do not attempt to quantify what percentage which I find curious. I think it weakens their above first statement possibly lowering the anthropogenic range. Very likely there’s been a contribution which might mean 1% to 100%. I think they botched their message when we try to reconcile the two.

Comment on New presentations on sea ice by Arno Arrak

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I see that you are off to discussing sea ice in China but nowhere is there any mention made of what I have written about it. Not because anyone has criticized me but because the mainstream, including yourself, has ignored it. That is a pity, because much of what is circulating about that subject is plain nonsense. Let’s start from the beginning. Observations of Arctic ice melting show it goes much faster than the greenhouse theory predicts. That is small wonder because demonstrably Arctic warming cannot be greenhouse warming. This is because it started from scratch at the turn of the twentieth century and to do this is impossible without an increase of atmospheric carbon dioxide. Laws of physics, you know. And we know for sure that there was no such increase of CO2 simply by looking at the Keeling curve. Right off the bat the greenhouse theory is in trouble but numerous authors writing about it ignore this fact and go off analyzing side issues. Refusing to face a fact will not make it go away and choosing to deal with side issues just obfuscates the situation. Further, the warming, once started, came to a halt in mid-century and thirty years of cooling followed. The cooling in turn came to an end in 1970 but none of the papers on Arctic warming even know it happened. Now we have two mysterious happenings – sudden start of warming and thirty years of cooling – that must be explained. And that means you too because you are one of these Arctic experts. Add to this the fact that prior to 1900 there was nothing in the Arctic but two thousand years of slow, linear cooling, and you have an unfinished research program on your hands. Look at the Kaufman et al. temperature graph in my article.It shows a couple of slight warmings as well as a slight cooling for LIA but a straight line for 2000 years is a reasonable overall approximation to it. And don’t overlook the NOAA Arctic report card I include. If you do it right you will have to explain at this point both the origin of warming and the mid-century cooling as well before going on. Since carbon dioxide is ruled out as cause the only reasonable physical explanation boils down to ocean currents. They would have to carry warm water to the Arctic to make this happen. The sudden start of warming most likely corresponds to a discontinuous change of North Atlantic current system when it first started to carry warm Gulf Stream water into the Arctic Ocean. Its origin is unknown and someone with their billions of climate research money should look into it. In this context, the thirty year pause in mid-century would correspond to a temporary return of the previously existing current system. There is no way that any greenhouse effect could perform such changes of direction in the short time available for this. All the papers on ice loss are blissfully unaware of these facts. But we know that something that has happened in nature can happen again. If that thirty year cooling should return it would not be too good for Arctic transportation or resource development. The last few years have shown a cooler side of the Arctic and the Northwest Passage has not been open to yachts that had planned to pass through. Perhaps the North Atlantic current system is ready to change its flow pattern again. I am not willing to guess, I am just watching to see how it will turn out.

Comment on Open thread by Pierre-Normand

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Rob Ellison: “I didn’t say this.”

Yes, sorry. I made a mistake editing. This was my own paraphrase of the trivial bit that we are agreeing on.

Comment on New presentations on sea ice by PA

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Mr. Gates…

The chart is not current or accurate.

The average sea ice extent – looks pretty average.

This year’s average extent will be over 11 million km2. Last years average was over 11 million km2. The chart of Mr. Gates is simply wrong.

The sea ice in the arctic has been increasing in volume for about 2 years. It might be recovering or it might just be torturing CAGW aficionados. Time will tell.


Comment on New presentations on sea ice by R. Gates

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Given the close correlation between latent heat of fusion and net energy in the Arctic, this excellent animation of sea ice volume gives one of the indications of the total energy in the Arctic. In the animation, the smaller this ice cube gets, the greater the net energy in the system:

https://m.youtube.com/watch?feature=youtu.be&v=nuKVk1gMJDg

Comment on New presentations on sea ice by beththeserf

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Stephen, trying ter recall where Wagathon wrote twenty-nine
paragraphs (plus sundries.)
bts

Comment on Open thread by Rob Ellison

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You’ve said this 10 times and been wrong 10 times. Notice that in the process of Joule expansion, the molecules *also* are free to bounce around and more widely disperse in the empty space newly opened to them, yet there is exactly zero loss of kinetic energy and zero drop in temperature — because there is no external work done. So, this process isn’t relevant to the case of adiabatic expansion withing a slowly expanding gaseous medium (e.g. more air parcels around) or expanding solid enclosure.’

There is a real gas temperature reduction from Joule expansion. But this is just one effect. Which I put at 3K over 5km it seems so long ago. Which is 1 order of magnitude less than the dry abiabatic lapse rate btw.

‘The two-way material diffusive flux at the notional boundary is irrelevant to the temperature drop in the middle of the expanding parcel since if there were a thin flexible boundary there (as the foil of a rising weather balloon) then there would be no diffusive flux at all but there would still be the very same temperature drop everywhere within the balloon…’

blah blah blah blah…

http://www.scientificamerican.com/article/if-heat-rises-why-does-th/

http://scienceprojectideasforkids.com/2010/temperature-changes-with-earths-atmosphere/

Look – the temperature is lower at height simply because there are fewer molecules per unit area. As air rises it expands into that space and cools. The expanding air mass diffuses into the surrounding space.

Comment on New presentations on sea ice by JustinWonder

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John Carter – “Once again…wrong.”

It’s nice to be concise.

Comment on Open thread by Rob Ellison

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Rob Ellison: “I didn’t say this.”

Yes, sorry. I made a mistake editing. This was my own paraphrase of the trivial bit that we are agreeing on.

I suppose it is this bit that he imagines is all that I am talking about.

I also granted to you that when the parcel of *real* gas expands, there is *some* (small) part the the reduction in KE of the molecules that is accounted for by the work of inter-molecular forces. It’s this reduction that’s isolated in the artificial Joule-Thompson throttling process. But this is several orders of magnitude smaller than the reduction in KE energy accounted for by the reduction in total internal energy (which you deny occur) that corresponds to dW.

It is at least some progress from insisting that the atmosphere is an ideal gas. The effect is some 3K/5km. The other effect of expansion is that there are fewer molecules per unit area each with some kinetic energy so the average is lower and T drops.

There is no work done (dW) on an imaginary boundary. Molecules expand outwards and diffuse into the surrounding space. This is the real effect – as I have said all along – and not the dry adiabatic lapse rate. The latter is a construct based on physical analogies to a mechanical system. I derived the dry adiabatic lapse rate, discussed the assumptions and moved on to the real world. P-N still has trouble with the derivation and seems incapable of processing reality.

I never particularly believe anything that P-N says. It is a peculiar logic of physical definitions in which the definition signifies reality – and he seems unable to see the distinction.

http://www.haveabit.com/feynman/2

Comment on Open thread by Rob Ellison

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Rob Ellison: “I didn’t say this.”

Yes, sorry. I made a mistake editing. This was my own paraphrase of the trivial bit that we are agreeing on.

I suppose it is this bit that he imagines is all that I am talking about.

I also granted to you that when the parcel of *real* gas expands, there is *some* (small) part the the reduction in KE of the molecules that is accounted for by the work of inter-molecular forces. It’s this reduction that’s isolated in the artificial Joule-Thompson throttling process. But this is several orders of magnitude smaller than the reduction in KE energy accounted for by the reduction in total internal energy (which you deny occur) that corresponds to dW.

It is at least some progress from insisting that the atmosphere is an ideal gas. The effect is some 3K/5km. The other effect of expansion is that there are fewer molecules per unit area each with some kinetic energy so the average is lower and T drops.

There is no work done (dW) on an imaginary boundary. Molecules expand outwards and diffuse into the surrounding space. This is the real effect – as I have said all along – and not the dry adiabatic lapse rate. The latter is a construct based on analogies to a mechanical system. I derived the dry adiabatic lapse rate, discussed the assumptions and moved on to the real world.

Rob Ellison: “I didn’t say this.”

Yes, sorry. I made a mistake editing. This was my own paraphrase of the trivial bit that we are agreeing on.

I suppose it is this bit that he imagines is all that I am talking about.

I also granted to you that when the parcel of *real* gas expands, there is *some* (small) part the the reduction in KE of the molecules that is accounted for by the work of inter-molecular forces. It’s this reduction that’s isolated in the artificial Joule-Thompson throttling process. But this is several orders of magnitude smaller than the reduction in KE energy accounted for by the reduction in total internal energy (which you deny occur) that corresponds to dW.

It is at least some progress from insisting that the atmosphere is an ideal gas. The effect is some 3K/5km. The other effect of expansion is that there are fewer molecules per unit area each with some kinetic energy so the average is lower and T drops.

There is no work done (dW) on an imaginary boundary. Molecules expand outwards and diffuse into the surrounding space. This is the real effect – as I have said all along – and not the dry adiabatic lapse rate. The latter is a construct based on physical analogies to a mechanical system. I derived the dry adiabatic lapse rate, discussed the assumptions and moved on to the real world.

I never particularly believe anything that P-N says. It is a logic of physical definitions.

Comment on Open thread by Rob Ellison

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Whoops – editing mishap looking for a moderation trigger – sorry


Comment on New presentations on sea ice by A fan of *MORE* discourse

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Rob Ellison praises “[Petr Chylek]“

What’s Petr Chylek been up to the past few years?

Peer-reviewed skeptic papers by Petr Chylek

This page lists any peer-reviewed papers by Petr Chylek that take a negative or explicitly doubtful position on human-caused global warming.

There are no peer-reviewed climate papers by Petr Chylek that meet this definition.

No arxiv preprints either.

Ouch. It seems that Chylek talked-the-talk, then didn’t walk-the-walk.

Not obviously a role model for young climate-scientists, eh Climate Etc readers?

\scriptstyle\rule[2.25ex]{0.01pt}{0.01pt}\,\boldsymbol{\overset{\scriptstyle\circ\wedge\circ}{\smile}\,\heartsuit\,{\displaystyle\text{\bfseries!!!}}\,\heartsuit\,\overset{\scriptstyle\circ\wedge\circ}{\smile}}\ \rule[-0.25ex]{0.01pt}{0.01pt}

Comment on Open thread by Pierre-Normand

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“There is a real gas temperature reduction from Joule expansion. But this is just one effect. Which I put at 3K over 5km it seems so long ago. Which is 1 order of magnitude less than the dry abiabatic lapse rate btw.”

That’s not really a big issue, but let me just quibble about this figure. Do you have a source for this 3°C/5km figure? You may be right but it seems high to me. Joule-Thomson expansion just is Joule expansion for a real gas. It isolates the temperature reduction effect due solely to inter-molecular forces (no external work). I would have thought it was much smaller based on the Joule-Thompson coefficient (partial derivative of T with respect to P at constant enthalpy) of molecular nitrogen, which ranges from 0.2 to 0.3 °K/bar in the approximate temperature range of the troposphere. I can’t find the figure for air but I assumed it was similar.

Since lifting a dry air parcel one kilometer above sea level would cool it by about 10°K according to the dry adiabatic lapse rate, and the pressure change is about 0.11bar, I expect something around 0.02 to 0.03°K as the internal (electrostatic potential) contribution to the temperature drop. That’s nearly 3 orders of magnitude smaller than the total effect from adiabatic expansion. Could the Joule-Thompson coefficient for air be nearly 20 times larger than for pure N2? Maybe so. I’d just like to see some figure.

Comment on Open thread by Pierre-Normand

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Rob Ellison, regardless whether the change in internal balance between electrostatic potential and molecular KE contributes 10% or 0.1% of the real temperature drop, you can only arrive at the conclusion that the total internal energy of the rising air parcel is conserves (albeit spread out in a larger volume) if you completely discount the other 90% or 99.9% of the effect. This had been my point all along. This larger portion of the effect is not attributable to the increased electrostatic potential share of the internal energy. Hence your claim that the total internal energy is conserved amounts to denying the much larger part of the effect on temperature.

Comment on New presentations on sea ice by Rob Ellison

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‘A multiple linear regression analysis of global annual mean near-surface air temperature (1900–2012) using the known radiative forcing and the El Niño–Southern Oscillation index as explanatory variables account for 89% of the observed temperature variance. When the Atlantic Multidecadal Oscillation (AMO) index is added to the set of explanatory variables, the fraction of accounted for temperature variance increases to 94%. The anthropogenic effects account for about two thirds of the post-1975 global warming with one third being due to the positive phase of the AMO. In comparison, the Coupled Models Intercomparison Project Phase 5 (CMIP5) ensemble mean accounts for 87% of the observed global mean temperature variance. Some of the CMIP5 models mimic the AMO-like oscillation by a strong aerosol effect. These models simulate the twentieth century AMO-like cycle with correct timing in each individual simulation. An inverse structural analysis suggests that these models generally overestimate the greenhouse gases-induced warming, which is then compensated by an overestimate of anthropogenic aerosol cooling.’

http://onlinelibrary.wiley.com/doi/10.1002/2014GL059274/abstract

‘Understanding Arctic temperature variability is essential for assessing possible future melting of the Greenland ice sheet, Arctic sea ice and Arctic permafrost. Temperature trend reversals in 1940 and 1970 separate two Arctic warming periods (1910–1940 and 1970–2008) by a significant 1940–1970 cooling period. Analyzing temperature records of the Arctic meteorological stations we find that (a) the Arctic amplification (ratio of the Arctic to global temperature trends) is not a constant but varies in time on a multi-decadal time scale, (b) the Arctic warming from 1910–1940 proceeded at a significantly faster rate than the current 1970–2008 warming, and (c) the Arctic temperature changes are highly correlated with the Atlantic Multi-decadal Oscillation (AMO) suggesting the Atlantic Ocean thermohaline circulation is linked to the Arctic temperature variability on a multi-decadal time scale.’ http://onlinelibrary.wiley.com/doi/10.1029/2009GL038777/abstract

‘The Greenland δ18O ice core record is used as a proxy for Greenland surface air temperatures and to interpret Atlantic Multidecadal Oscillation (AMO) variability. An analysis of annual δ18O data from six Arctic ice cores (five from Greenland and one from Canada’s Ellesmere Island) suggests a significant AMO spatial and temporal variability within a recent period of 660 years. A dominant AMO periodicity near 20 years is clearly observed in the southern (Dye3 site) and the central (GISP2, Crete and Milcent) regions of Greenland. This 20-year variability is, however, significantly reduced in the northern (Camp Century and Agassiz Ice Cap) region, likely due to a larger distance from the Atlantic Ocean, and a much lower snow accumulation. A longer time scale AMO component of 45–65 years, which has been seen clearly in the 20th century SST data, is detected only in central Greenland ice cores. We find a significant difference between the AMO cycles during the Little Ice Age (LIA) and the Medieval Warm Period (MWP). The LIA was dominated by a ∼20 year AMO cycle with no other decadal or multidecadal scale variability above the noise level. However, during the preceding MWP the 20 year cycle was replaced by a longer scale cycle centered near a period of 43 years with a further 11.5 year periodicity. An analysis of two coupled atmosphere-ocean general circulation models control runs (UK Met Office HadCM3 and NOAA GFDL CM2.1) agree with the shorter and longer time-scales of Atlantic Meridional Overturning Circulation (AMOC) and temperature fluctuations with periodicities close to those observed. However, the geographic variability of these periodicities indicated by ice core data is not captured in model simulations.’

http://onlinelibrary.wiley.com/doi/10.1029/2012GL051241/abstract

There is no sceptic science – merely actual science that is reaching an inconvenient conclusion. Ouch.

Comment on New presentations on sea ice by beththeserf

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Stephen Segrest asks’ What’s the standard?’ Seems it’s
‘keep non consensus papers O – U – T.’ See the CRU
emails regarding gate-keeping tactics.

Phil Jones, July 8, 2004… ‘Kevin and I will keep them
out somehow, even if we have to redefine what the
peer literature is!’

And more, Michael Mann, Uncle Tom Quigley and al
within those consensus-publicly-funded-cli-sci-enclaves.

http://www.passionforliberty.com/2013/08/19/climategate-coverup/

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