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Pmt111500

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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #50 on: March 19, 2017, 04:44:51 AM »
Randy,

The majority of the scientists and engineers do not have the skills to be concise,  on target and quick on come backs. It is unfortunate...

Yep, it comes with the job description. Many, coming to science, are hoping to make a big discovery. On one short 'philosophy of science'-course I took the lecturer said on most lessons 'the first thing to doubt is yourself". There were several reiterations of this too.
« Last Edit: March 19, 2017, 04:53:58 AM by Pmt111500 »
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6roucho

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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #51 on: March 19, 2017, 04:45:03 AM »
Sorry I am beginning to rant!!! ;-) Maybe it was the sales guy dig. It is the same as I used to do because I am actually a technical man originally and a sales guy by providence (accident).
It wasn't a dig, Ranman99, it was a compliment. This is veering off topic, but sales is a highly skilled activity. One you've learned to do, and good on you. Public relations is the same. When scientists try to do public relations, such as by giving interviews, they're like PR people doing experiments by putting stuff in beakers and heating it up. It may by some chance be mostly correct [e.g. they've seen it done so know roughly how to do it] but it's only scratching the surface of a highly complex process.

Again, there are individual exceptions, but even the best public intellectuals need the machinery of communications in place to change opinions. In science, this is often provided by the mainstream media. Without them, public knowledge of science would be sunk.

MrVisible

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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #52 on: March 19, 2017, 05:58:02 AM »
Randy,

The majority of the scientists and engineers do not have the skills to be concise,  on target and quick on come backs. It is unfortunate...

Those skills take quite a bit of work to master. Debate club in college helps a lot, as does law school or a communications degree. These are people who study deceptive rhetoric the way scientists study science; it's no surprise that scientists are often outgunned in the media.

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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #53 on: March 19, 2017, 12:03:17 PM »
Hello ASIF,
My first post ever here, although I am an avid reader of this forum and have great respect for the fabulous work by Neven and team. I am not a climate scientist and am just posting an opinion as a concerned citizen of the world. And the reason I am posting my very humble opinion on this precise topic is that I believe this particular paper by Ding et al makes a dangerous argument at a critical time in human history.
To summarize my opinion, I think this article begs three questions:
1) Is the argument made in the article, that the disappearance of Arctic sea ice in summer could be attributed in a large part to "natural climate variability" (that's the precise expression used in the abstract of the paper), scientifically correct?
2) I have long thought - and I think many here share the same belief - that Arctic sea ice is "the canary in the mine" (https://en.wiktionary.org/wiki/canary_in_a_coal_mine) of climate change. The article by Ding argues exactly the contrary, and as pointed out by jai mitchell above, weakens the scientific, economic and political argument that urgent and radical emissions reductions policies should be adopted ASAP, to avoid the worst effects of global warming / climate change / ocean acidification. So, is it the responsibility of scientists to avoid publishing such an article , or do scientists live in a vacuum, and can publish whatever they want whenever they feel they have a valid scientific argument?
3) Since October 2016 and up until now (mid-March 2017), we have had global sea ice extent record lows, many standard deviations below average. Clearly, this is not natural variability and even way below trend lines, not only for Arctic sea ice, but also for Antarctic sea ice. Like many here, I feel we have entered a new regime for our global climate, and this is clearly reflected in what is happening with sea ice at both poles. Or, if you prefer, the "canary in the mine" of global warming just died.
This should ring an alarm bell for climate scientists and political leaders worldwide, yet at precisely this point in time there comes an article that essentially says there is no such canary in the mine and the disappearance of Arctic sea ice is mostly attributable to "natural climate variability".
Essentially I am claiming that the timing for the publication of this article is highly suspicious. And yes, that is sort of a conspiracy theory.  :o

My opinion here, just to be clear, is that:
1) The disappearance of Arctic sea ice year round is definitely and more than 100% caused by GHG emissions from human activity. In other words, the Ding et al article is scientifically questionable.
2) No, scientists don't live in a societal vacuum and should take responsibility for the science they produce or don't produce, specially when millions of human lives are at stake. (https://en.wikipedia.org/wiki/Einstein%E2%80%93Szil%C3%A1rd_letter, James Hansen's testimony in Congress in 1988, etc)
3) Just when we have a very clear sign, evidenced by irrefutable data, of irreversible climate change attributable to anthropogenic fossil carbon emissions and at a critical time when public policies worldwide should be put in place to reduce those emissions, we have a highly questionable scientific paper that gets published dismissing this very sign of irreversible climate change as "natural variability". I find this coincidence highly improbable.

Just a few charts to support my opinions above, mainly that the disappearance of sea ice is NOT due to any kind of "natural climate variability", despite what Ding's "improved" models may show or not:

Neven

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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #54 on: March 19, 2017, 12:43:03 PM »
Welcome to the ASIF, AndrewB. Your profile has now been released.
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Andre

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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #55 on: March 19, 2017, 01:30:15 PM »
Welcome, AndrewB! Nice first post to get started on the forum and hopefully not your last!

I fully agree with your main arguments. Considering the possible catastrophic climate change outcomes and the already lacklustre response of most people and governments around the world, it is crucial that everybody takes responsibility for how they present new studies, facts and evidence.

 It is more important than ever for all of us to appreciate that messaging matters and the same results, presented differently, would have evoked a very different kind of response.

As has been pointed out above, that might simply portray a lack of effective communication and PR skills and say less about any alterior motives.

However, I dont know, if we can afford to be so seemingly unskilled at effective PR much longer. The negative side effects will eventually catch up with us.

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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #56 on: March 19, 2017, 04:09:27 PM »
Welcome Andrew,

I find this coincidence highly improbable.


Here's yet another "coincidence" for you to consider, extremely hot off the (literal!) presses:

"Don’t Panic! It’s Just Another Climategate 2 Correction!!"

Snow White’s very good friend Alice F. with her planet-wide patent pending hyper-sensitive wetware alternative facts detector is now on the case:
Reality is merely an illusion, albeit a very persistent one - Albert Einstein

jai mitchell

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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #57 on: March 19, 2017, 07:34:50 PM »
tzupanic, thanks for the paper.  Here is a quote from the paper:

Having attributed a substantial part of September sea ice decline to variability in the high
latitude circulation during the preceding summer, we now examine whether long-term changes in
the circulation are driven by natural or anthropogenic variability. Upper tropospheric circulation
change in the Arctic is subject to strong natural variability originating from the tropics.
Previous research identified a relationship between tropical SST variability and annual mean
atmospheric circulation over the Arctic with a center of action over Greenland. Model
experiments show that about 50% of the circulation change and the associated warming over
Greenland is attributable to natural variability originating from the tropical Pacific Ocean. An
“ad hoc” attribution through a combination of these components suggests that ~30% (= 50% ×
60%) of the sea ice decline observed since 1979 during JJA is attributable to natural variability in
the tropical Pacific


To this my question is, are sst's over the pacific affected by Human forcings? Well the answer is of course yes!

They attribute the changes in the atmospheric patterns to changes in the pacific, but they pretend that the changes in the pacific are natural. That's crazy talk.


WRT tropical humidity translation northward to the arctic I would recommend everyone read this paper thoroughly:  http://www.atmos-chem-phys.net/16/14331/2016/acp-16-14331-2016.pdf

my commentary is here: http://forum.arctic-sea-ice.net/index.php/topic,1384.msg96264.html#msg96264

I can guarantee you that this physical reality and the consequences of China shutting down its 30 most sulfur producing coal mines and installing scrubbers is NOT considered in their model as anthropogenic but is rather attributed to 'natural variability'.

quote below: not only are powerful dynamics NOT included in the models, the spacial resolution of the models and impacts on atmospheric circulation are not competent enough to accurately project the impacts that ARE included due to regional scale impacts on atmospheric circulation

Results from general circulation models show almost no
changes in the relative humidity in a changing climate (Held
and Soden, 2000; Soden et al., 2005). However, very few
general circulation models have so far begun to include the
effects of aerosols on deep convective clouds (Boucher et
al., 2013; Khain et al., 2015). Namely, as noted by Khain
et al. (2015), the only feasible option in current general circulation
models is to use bulk microphysics parameterisation
schemes. However, bulk microphysics schemes have trouble
producing the effects of aerosols on cloud cover and cloud
top height. As a result, the effect of aerosols on UTH is
not correctly included in the current projections of climate
change produced by general circulation models. Estimates
of climate sensitivity that combine temperature observations
with estimates of greenhouse gas and aerosol-induced radiative
forcing should also be reconsidered.
« Last Edit: March 19, 2017, 07:40:15 PM by jai mitchell »
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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #58 on: March 19, 2017, 07:48:18 PM »
AndrewB

thank you for your cogent statements.  I have long suspected that there are factions within the scientific community that work within the normal frameworks to provide contrarian views to reduce the mitigation imperative.  For example the Barnes' paper that used cherry picking to contrast Vavrus & Barnes Francis (2013) RE: 'wavier' jet stream due to reduced temperature gradients.  Also Nordhaus' work for his entire career, the actions of his apprentice Tol on falsifying economic impacts (lower) under RCP 8.5 the list of questionable activity goes on and on it is not likely that all scientific hacks working to prevent mitigation are invited before a republican congress to publicly testify their lies.
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Jim Williams

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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #59 on: March 19, 2017, 10:32:03 PM »
...is that I believe this particular paper by Ding et al makes a dangerous argument at a critical time in human history.
OK...What is dangerous about it, and why should he not make a dangerous argument?

My vague sense in scanning it that it is crap, but the only thing dangerous about crap are the worms which might wait within it.


oren

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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #60 on: March 19, 2017, 10:35:59 PM »
AndrewB, welcome and thank you for putting it so concisely. To me argument 1 is still the most important, and I find the scientific claim highly questionable. The negative arctic sea ice trend is so obvious that attributing it to variable natural causes unrelated to AGW and GHGs using a model, probably means the model is not good enough.

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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #61 on: March 19, 2017, 11:30:18 PM »
My vague sense in scanning it that it is crap, but the only thing dangerous about crap are the worms which might wait within it.

Yes, because experts who have studied the subject and been at the top of their fields for a couple of decades or more are more likely to produce crap than your vague sense.

STFU already.

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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #62 on: March 19, 2017, 11:55:50 PM »
on the Nature site with the abstract I saw a link to this article "The missing Northern European winter cooling response to Arctic sea ice loss" http://www.nature.com/articles/ncomms14603 which is interesting. I interpret it as saying that variations (in that case the NAO) can have different effects as the background trend shifts (in that case sea ice cover).
This gave me the following idea:
In a situation where the fluctuations can reinforce the trend (sea ice loss) that may ratchet the trend into a domain in which the fluctuation in the opposite direction will have less of an effect.

Pragma

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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #63 on: March 20, 2017, 12:17:26 AM »
My vague sense in scanning it that it is crap, but the only thing dangerous about crap are the worms which might wait within it.

Yes, because experts who have studied the subject and been at the top of their fields for a couple of decades or more are more likely to produce crap than your vague sense.

STFU already.

Wow! When it comes to logical fallacies, you almost have a twofer there. First, an appeal to authority, which is to say, no argument at all. Second, your uncalled-for rudeness is very close to an ad hominem attack.

May I suggest an actual scientific discussion instead?

Cid_Yama

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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #64 on: March 20, 2017, 12:35:04 AM »
<snip, not helpful or useful; N.>
« Last Edit: March 20, 2017, 12:49:48 AM by Neven »

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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #65 on: March 20, 2017, 12:38:42 AM »
May I suggest an actual scientific discussion instead?

There will be one if everyone stops jumping on each other, instead of ignoring the stuff that irritates for a while. Makes it easier for me to moderate as well.
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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #66 on: March 20, 2017, 12:56:41 AM »

To this my question is, are sst's over the pacific affected by Human forcings? Well the answer is of course yes!

They attribute the changes in the atmospheric patterns to changes in the pacific, but they pretend that the changes in the pacific are natural. That's crazy talk.

Of course CO2 is impacting Pacific SSTs.  But we also know there are significant natural variations at work over multi-decadal time frames in the tropical Pacific, namely PDO.

Looking at a trend in SSTs from 1979 to 2016 in GISS shows a significant cool PDO/ENSO signal over the time period in question.  Is Co2 causing a trend towards cooler PDO/ENSO?  If so the pause may not be totally a natural variation, but rather a negative feedback on global warming.  Or is this cooling due to a  natural variation?

I've noted in the past that the fastest loss in Arctic ice loss corresponds roughly to the period of pause in global temp increase.  Could easily be coincidence, but research linking both the pause and now the Arctic ice to tropical Pacific temps suggests something more. 

Models have tended to suggest that CO2 is more likely to contribute to warmer ENSO/PDO conditions, although there seems to be variation, and I'm not yet fully convinced (I like the idea that Co2 warming would lead to cool PDO, primarily due to faster warming of surface waters than deep waters leading to a cooler ENSO tongue in comparison to rest of ocean).  Recent ENSO behaviour has been on the warmer side again and it looks like we may be back to a warm PDO phase.  We still haven't beaten the summer minimum of 2012, and we could be in a period of enhanced global warming, and reduced Arctic ice loss (at minimum)

edit:  It also occurs to me that we may be in a new circulation pattern, but this pattern is not quite an opposite of the previous dipole type pattern.  A nice natural cycle may immediately balance out a period of bad for ice pattern with a good for ice pattern.  But reality may switch from a bad to ice pattern to neutral, or even just less bad.
« Last Edit: March 20, 2017, 01:02:11 AM by Michael Hauber »
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Archimid

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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #67 on: March 20, 2017, 02:11:50 AM »

Of course CO2 is impacting Pacific SSTs. 

Yes, but is not just CO2. There are industrial Aerosols like the ones jai mitchell keeps pointing at, there is deforestation that change the cloud patterns and temperatures, there is the accumulated warming in the Oceans ect.

But we also know there are significant natural variations at work over multi-decadal time frames in the tropical Pacific, namely PDO.

Yes, but the PDO is affected by human influence. I prefer "significant random variations" to  "significant natural variations". To me the word "Natural" has the connotation that the variation is beyond human influence. I find that extremely unlikely. I think "natural" is an improper term.

Looking at a trend in SSTs from 1979 to 2016 in GISS shows a significant cool PDO/ENSO signal over the time period in question.  Is Co2 causing a trend towards cooler PDO/ENSO?  If so the pause may not be totally a natural variation, but rather a negative feedback on global warming.  Or is this cooling due to a  natural variation?


I've noted in the past that the fastest loss in Arctic ice loss corresponds roughly to the period of pause in global temp increase.  Could easily be coincidence, but research linking both the pause and now the Arctic ice to tropical Pacific temps suggests something more. 


The first two images are crappy screenshots of the PDO according to NOAA and global Temperatures according to GISStemp from about 1979 to today.

Please notice that from around 1979 the PDO was mostly positive and global temperatures rose steadily until around the 90's. In the early 90's the PDO took  a dive and so did global temperatures. Then around 1998 the PDO switched to mostly negative and global temperatures stopped rising. Then after 2012 the PDO switched back to positive and the global temps followed.

The third image is Arctic sea ice extent. During this whole time Arctic sea ice was on decline. During the times of warming and during the times of cooling ice is being lost.

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tzupancic

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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #68 on: March 20, 2017, 02:15:28 AM »
In response to a number of posts discussing the issue of communication with a general audience and whether scientists in general or the authors here should be criticized for their language/format/style; here is an example of the climate denialist reaction; “Natural Variability’s Role in Arctic Sea Ice Decline Strengthens Case for Lukewarming”.

https://www.cato.org/blog/natural-variabilitys-role-arctic-sea-ice-decline-strengthens-case-lukewarming

In perusing this argument the concept of sophistry immediately comes to mind.

The logical incongruity in the last few paragraphs stands out. Cato’s fallacy begins with “But if a sizeable proportion of the ice loss is being caused by natural variability (and not greenhouse gas emissions), then some proportion of the warming observed over the past 30 years must be caused by the same forces of natural variability”… their contrived argument spins illogically out of control from there.

Cato incorrectly asserts, “This means that when comparing the rates of observed warming with the rates of warming expected by climate models, that natural variability acting on Arctic sea ice has been making the models seem to be closer to reality than they actually are.”

Huh! ???  The premise of the paper is that models do not explain the observed Arctic melt, so some other factor must be involved. Thus, they modified the model.

Cato goes illogically downhill from there, asserting the complete opposite of the finding of the study which is that the observed melt of Arctic Sea Ice can indeed be explained by geophysics. And that human activity has been a major driver.

tzupancic

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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #69 on: March 20, 2017, 02:43:19 AM »
Regarding the semantic definition of ‘Natural Variations’ the recent discussion in climate science about changes in the variability of Northern Hemisphere Jet Stream comes to mind. Given that the Jet Stream naturally varies, if the frequency, magnitude and intensity of such variations are observed to change in a concerted way over time, in correlation with key factors driven by human activity, is such a variation still ‘natural’?  Similarly, if Arctic Sea Ice melt is observed to correlate with increased heat in the climate system resulting from human activity and also changes in atmospheric circulation (kind of sounds like changes in the jet stream…) How does one determine that an observed change in a complex process is natural and not driven by other factors known to be altering the system?


tzupancic

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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #71 on: March 20, 2017, 03:18:25 AM »
Just fyi, I once posted at some length on an obscure Solar Cycle 24 discussion forum about the Arctic Sea Ice that was dominated by climate change denialists. I learned a thing or two. If it matters, I am a Ph.D. scientist.

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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #72 on: March 20, 2017, 04:37:40 AM »
The third image is Arctic sea ice extent. During this whole time Arctic sea ice was on decline. During the times of warming and during the times of cooling ice is being lost.

See Tamino's Analysis from October 2015.  Here he shows evidence of faster ice loss during the last decade, and a slow down in recent years.  While he does not actually say the difference is statistically significant, from what I've seen of Tamino he would not put the break points in that chart if they weren't.



Also see a more recent post with a Lowess smooth.  The recent years are definitely downward instead of close to level.  A  period of faster reduction is still visible, but as this is Lowess smooth and Tamino makes no specific comment there is no particular support for a change in speed, but the data is closer to up to date.
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Archimid

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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #73 on: March 20, 2017, 04:44:07 AM »
The way I look at it the sun is the primary driver of the Earth's climate.Greater than 99.9% of the sun's influence is constant in Human time frames. The .1% of that energy that is not constant is the only "Natural" (free of human influence) variation left.

 .1% is such a small variation that for many (most?, all?) applications the total energy received from the sun can be used as a constant, but it is not constant it varies. Even if that variation is small, the sun probably varied about the same way for hundreds of millions of years. That means that all potential forces on the planet are influenced by the same  force. The big synchronization is with gravity, the topography of the planet, the day and night cycle. Over time I imagine that synchronization occurs between the photosynthetic biosphere and its dependencies.

I believe that variations like the PDO can be eventually tracked to solar variation but with lag determined by the many multi scale processes.

The PDO is indeed a natural variation. The thing is that with human induced warming the synchronicity is altered. For something like the PDO Natural is that when the PDO is positive, the global temperatures go up. When it is negative the global temperatures go down. However, we changed that. Under CO2 induced warming when the PDO is positive the temperature rises fast and when it is negative the temperature merely stops rising. The inevitable result is global warming.

Atmospheric currents are no different. They evolved under the same influences for millions of years. Now that we made the planet more energetic they must change. The change might be have been too small to notice for years, or perhaps the patterns were too complex to discern changes with accuracy, but the most basic physics dictate that the atmospheric currents must change with changes in temperature.



I am an energy reservoir seemingly intent on lowering entropy for self preservation.

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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #74 on: March 20, 2017, 08:36:01 AM »
In response to a number of posts discussing the issue of communication with a general audience and whether scientists in general or the authors here should be criticized for their language/format/style; here is an example of the climate denialist reaction; “Natural Variability’s Role in Arctic Sea Ice Decline Strengthens Case for Lukewarming”


Thanks for the heads up. However in response to your posts discussing climate denialist communications perhaps I might take this opportunity to criticize your style? Please do not give the likes of Messrs Michaels and Knappenburger the oxygen of publicity by linking to their hogwash. Instead link to archived versions like this one:

http://archive.is/wbTfu

Here is a list of such archived climate denialist reactions:

http://GreatWhiteCon.info/2017/03/is-arctic-ice-loss-driven-by-natural-swings/#AltDenialist

Here once again is a further helpful hint:

http://GreatWhiteCon.info/2017/03/is-arctic-ice-loss-driven-by-natural-swings/#comment-219940

I take it you are aware that the lunatics are now in charge of the asylum?

http://GreatWhiteCon.info/2017/03/that-deaf-dumb-and-blind-kid-sure-plays-a-mean-climateball/#comment-220045
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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #75 on: March 20, 2017, 12:03:15 PM »
Archimid,

You do not need a variable sun to create a PDO or any other natural oscullation. Just the shape and evolution of Earth' s orbit with local local Ocean and land topography is enough.
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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #76 on: March 20, 2017, 12:56:08 PM »
Eric steig
2017/03/20
Jim hunt: your question being whether we “saw this coming”?
I certainly did. I written or been involved with that a number of papers that more or less say’ “hang on folks, not every bump and wiggle is forced change; much of it is intrinsic variability (or at least, more work is needed to demonstrate otherwise.” The response is always as expected from the no-nothings, which is some combination of quoting us as showing that natural variability dominates (no, we didn’t), and claiming that the scientific mainstream has previously ignored natural variability. I’m more surprised when I get criticism from my colleagues who’ve usually not yet read the paper carefully, though I’m beginning to get used to that. Should we have done something different? I don’t know what. Not published the paper, lest we inadvertently help the “skeptics”? Put in more disclaimers (I thought we had, actually)?

Archimid

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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #77 on: March 20, 2017, 02:36:00 PM »
Archimid,

You do not need a variable sun to create a PDO or any other natural oscullation. Just the shape and evolution of Earth' s orbit with local local Ocean and land topography is enough.

Yes of course. The PDO oscillation exists because of the topography of the planet and it would probably oscillate even if the sun was truly constant. From my perspective, if the sun was constant then the PDO would be more predictable that it is now. However the variation of the sun, even as small as it is, have reinforced and weakened oscillations like the PDO at regular intervals for millions of years. Over time that small reinforcing and weakening eventually influences the variability to the point where the variations are highly coupled with solar cycles after lag from multi scale processes is accounted for.

 A simple correlation of the PDO and solar cycles might not easily show this because of the many multi scale process involved and the shortness of the record. But if we had a record of the PDO for the last, I don't know, 10000 years and an equally good record of solar variation for the same time period I think a strong correlation would be found between solar variation and PDO cycles.

In that imaginary 10k year data set it could be observed that correlation weakens as it advances through the 20th century and human induced warming breaks the coupling that took millions of years to form.

TL;DR: The PDO is a natural variation whose magnitude and interaction with the rest of the system changed because of human induced warming.





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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #78 on: March 20, 2017, 03:38:23 PM »
Eric steig
2017/03/20
Jim hunt: your question being whether we “saw this coming”?


In case it's not obvious, Crandles' quote was extracted from The Stoat. One of my follow up questions for Eric over there:

Any thoughts on this recent comment of mine at Neven’s Arctic Sea Ice Blog?

http://neven1.typepad.com/blog/2017/03/lowest-maximum-on-record-again.html?cid=6a0133f03a1e37970b01b8d26c9d01970c#comment-6a0133f03a1e37970b01b8d26c9d01970c
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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #79 on: March 20, 2017, 05:38:53 PM »
First, thank you Neven for practically immediately releasing my profile and welcoming me into the ASIF community. Also, thank you Archimid for starting this thread, and thank you Andre, Jim Hunt, jai mitchell, Jim Williams and oren, for your replies/comments.

Jim Williams, you ask: “OK...What is dangerous about it, and why should he [Ding et al] not make a dangerous argument?”

The argument that the demise of Arctic sea ice is in large part due to “natural climate variability” is dangerous because it feeds the rhetoric of the “merchants of doubt”, that climate change - as much as they accept that there is anything at all like climate change going on – is a “natural” phenomenon, etc. The ultimate conclusion of any such argument being that we don’t need to slow down or stop mining/extracting fossil carbon, and burning such fossil carbon and emitting GHG’s. In other words, let's keep the fossil carbon industry going.

Or, as jai mitchell put it in much better words than mine:
“… there are factions within the scientific community that work within the normal frameworks to provide contrarian views to reduce the mitigation imperative.”


Kevin Anderson and Glen Peters think along similar lines when they discuss the reliance of various emissions scenarios on negative emissions, the technology for which, as of March 2017, simply doesn’t exist. (see http://www.geoengineeringmonitor.org/2016/10/the-trouble-with-negative-emissions/) Negative emissions are a neat doublethink-like trick to justify the convenient concept of a “carbon budget”, in other words, how much extra carbon we can still burn if we want to keep global warming under 2C.

Michael E. Mann has previously calculated that if we wanted to keep global warming under 2C, we would have to keep CO2 concentration under 450ppm; that was allowing for a 0.5C overshoot for a few decades, AND the widespread use of negative emission technologies after 2050. Without the widespread use of negative emission technologies after 2050, we would have to keep CO2 concentration under 405ppm. (see https://www.scientificamerican.com/article/earth-will-cross-the-climate-danger-threshold-by-2036/)

We are already at 405ppm. In other words, without relying on negative emissions technologies that as of March 2017, do not exist, our “carbon budget” is zero. We have to stop emitting GHG’s right now (the “mitigation imperative” that jai mitchell mentions). Bad news for fossil fuel companies? No, not really. Even the Paris agreement doesn’t consider the possibility of immediately implementing zero net emissions worldwide.

And, one can expect the next IPCC report to fully rely on emissions scenarios that include increasingly massive negative emissions beginning at around 2050. Are IPCC climate scientists – or even Michael Mann – going around claiming that the 2C limit is unrealistic? No they aren’t.

Similarly, the complete disappearance of Arctic sea ice – not only during summer, but year round – is by now totally inevitable in the space of a few decades, as one of the charts I posted in my first comment shows. Unfortunately, the argument made by Ding et al in their paper will lead to the following cynical discourse, which will be duly relayed to the general public by mainstream media:

But hey, if it’s due to “natural climate variability”, it has nothing to do with the fossil carbon industry, right?

And to all those who claimed that Arctic sea ice was “the canary in the mine” of climate change here is the news for you: Science says it ain’t so. The canary may be dying or have died, but it was from natural causes.


So, while we waste time discussing whether or not the paper by Ding et al is scientifically correct, "Bad Science" or just crap, or should have been worded differently, Arctic sea ice will continue to silently melt away and the fossil carbon industry will keep digging/extracting millions of tons of fossil carbon, to be released as GHG’s into the atmosphere.

Eric Steig, one of the authors of the paper, asks (thank you Jim Hunt for posting the exchange): “[Should we] Not [have] published the paper, lest we inadvertently help the “skeptics”?” The answer, imho, is pretty obvious.

crandles

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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #80 on: March 20, 2017, 06:06:19 PM »

Eric Steig, one of the authors of the paper, asks (thank you Jim Hunt for posting the exchange): “[Should we] Not [have] published the paper, lest we inadvertently help the “skeptics”?” The answer, imho, is pretty obvious.

IMHO the answer is pretty obvious that yes they should publish provided they put in appropriate caveats. If the answer was no then how do you expect science to advance? Also note the "quoting us as showing that natural variability dominates (no, we didn’t)". That seems pretty clear that the authors are not expecting a huge bounce back up by 60% of the drop. I would have preferred that to have been stated more clearly so as to reduce the chances of the paper being spun in the way it has been but however clearly done, do we really expect that to make much difference to how it is spun?

AndrewB

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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #81 on: March 20, 2017, 06:54:36 PM »

Eric Steig, one of the authors of the paper, asks (thank you Jim Hunt for posting the exchange): “[Should we] Not [have] published the paper, lest we inadvertently help the “skeptics”?” The answer, imho, is pretty obvious.

IMHO the answer is pretty obvious that yes they should publish provided they put in appropriate caveats.
...

Hi crandles,
Actually the Ding paper is generously sprinkled with caveats. But that has never prevented the fossil fuel industry propaganda writers from running with whatever argument they could extract from any scientific or opinion paper that would feed their rhetoric. If you don't believe me, just check Jim Hunt's blog for how mainstream media is "reporting" on this Ding et al paper.

So, unfortunately, I don't agree with you. Responsible, intelligent adults don't feed the narrative that Arctic sea ice is melting because of "natural climate variability". This paper should not have been published. And I am not even commenting on its scientific value, which imho is below the temperature (in degrees Celsius) at which ice transitions from solid to liquid.

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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #82 on: March 20, 2017, 07:36:35 PM »

Eric Steig, one of the authors of the paper, asks (thank you Jim Hunt for posting the exchange): “[Should we] Not [have] published the paper, lest we inadvertently help the “skeptics”?” The answer, imho, is pretty obvious.

IMHO the answer is pretty obvious that yes they should publish provided they put in appropriate caveats.
...

Hi crandles,
Actually the Ding paper is generously sprinkled with caveats. But that has never prevented the fossil fuel industry propaganda writers from running with whatever argument they could extract from any scientific or opinion paper that would feed their rhetoric. If you don't believe me, just check Jim Hunt's blog for how mainstream media is "reporting" on this Ding et al paper.

So, unfortunately, I don't agree with you. Responsible, intelligent adults don't feed the narrative that Arctic sea ice is melting because of "natural climate variability". This paper should not have been published. And I am not even commenting on its scientific value, which imho is below the temperature (in degrees Celsius) at which ice transitions from solid to liquid.
I think it was appropriate to publish  as long as it passed peer review.  It is dangerous to politicize research.

That said, I think it is behooves us and them to better delineate the source of that natural climate variability, as I expect climate change outside of the Arctic has affected it and shifted it's range of variation.
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crandles

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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #83 on: March 20, 2017, 07:54:19 PM »

So, unfortunately, I don't agree with you. Responsible, intelligent adults don't feed the narrative that Arctic sea ice is melting because of "natural climate variability". This paper should not have been published. And I am not even commenting on its scientific value, which imho is below the temperature (in degrees Celsius) at which ice transitions from solid to liquid.

To me this translates to I have a closed mind and will never accept that I am wrong on this issue whatever and however the science develops, I am going to keep the same opinion.

Even if it is wrong, the scientific way to find out is publish and be damned. (or not damned)

and yes re 'as long as it passed peer review'.

AndrewB

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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #84 on: March 20, 2017, 08:58:45 PM »
...
Even if it is wrong, the scientific way to find out is publish and be damned. (or not damned)
...
Hi crandles,
Again, I am not even arguing about the scientific value of the Ding paper per se here, or how it was worded, or how many caveats it was filled with.

I am talking about giving the "merchants of doubt" an excellent basis for further delaying the urgent and radical emissions reductions policies that need to be put in place to avoid the worst consequences of global warming - including famines, wars, forced migration, etc, and the suffering and ultimately death that these will bring to hundreds of millions of human beings.

So, are you a moral human being first and (questionable) scientist second, or does your oversized ego take precedence? In the case of Ding and his ten(!) co-authors, it seems the latter.

"Science sans conscience n'est que ruine de l'âme." - Rabelais

Now, of course since they have already been published, they have legitimized the clearly false assertion that the year-round disappearance of Arctic sea ice which will occur over the coming few decades is mostly due to "natural climate variability". You could demonstrate that they are entirely wrong, de-construct all the fallacies in their tortuous reasoning, dissect their various logic mistakes, point to each and every dubious assumption they make in the paper, it wouldn't matter: they cannot be unpublished. And clearly, people with such an oversized ego are not going to retract themselves or even admit that they were wrong and wrote a piss-poor excuse of a climate science paper.
So there you have it.
Arctic sea ice is going to disappear over the coming years but now the takeaway from this man-made disaster is that it's mostly "natural climate variability". Crappy (un)science is the new normal.
Talk about improving communications between climate scientists and the general public!
« Last Edit: March 24, 2017, 10:18:30 PM by AndrewB »

mikkel

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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #85 on: March 20, 2017, 10:00:22 PM »
Andrew, I completely agree with you about our dire straits. I continuously get frustrated that the scientific community is in a bit of denial about what their own work shows and that even many who aren't in denial haven't been public about it.

The only high profile examples of scientists who I know accurately communicate the "true" consensus are Michael Mann and James Hansen, with Jason Box chipping in on Greenland. Even then, only Hansen has proper emotional sense of urgency in his communication, although this often gets entirely lost when talking in specifics (which he acknowledges).

As I am apt to comment, the consensus is that 4-5C of warming is enough to threaten civilization itself, and the supposedly radical Paris targets are actually for 6C long term. Therefore our "goal" is civilization collapse!

That said, I feel you are being way too hard on these scientists. I completely understand why, as I went through the same phase of grief myself. It drove me to spend many years study propaganda and the nature of mass social movements, with the purpose of somehow teaching scientists how their actions are contributing to the problem.

Instead I came to discover the root of the problem lay in lack of solid leadership and compassion for how society operates. Those of us who genuinely see reality spend our time trying to communicate and get people to understand, because this is what personally moves us. However, it is not the principal driver for the vast majority of people, and in fact information overload causes them to dig in their heels.

By contrast, propagandists are skilled in leading the masses by tailoring communication in ways that are most effective for mass influence.

The fact is that data and models have almost no real contribution to denier propaganda. They literally make up shit even about the most straightforward and clear science, and if it is too hard to spin then it is just ignored. It seems to us that every single statement and paper must be perfect so that we cannot be taken advantage of (e.g. ClimateGates) but this is a trap: the obsession with accuracy and consistency only brings us further down the rabbit hole of disconnection. At its worst, it leads to internal conflict and ad hominems that break down cooperation.

I would strongly recommend you read "Don't Even Think About It" by George Marshall, who does an excellent job of showing how we all contribute to paralysis on social change, and how the propagandists (of which he interviews one) are only a very small part of the puzzle.

jdallen

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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #86 on: March 20, 2017, 10:02:54 PM »
...
Even if it is wrong, the scientific way to find out is publish and be damned. (or not damned)
...
Hi crandles,
Again, I am not even arguing about the scientific value of the Ding paper per se here, or how it was worded, or how many caveats it was filled with.

I am talking about giving the "merchants of doubt" an excellent basis for further delaying the urgent and radical emissions reductions policies that need to be put in place to avoid the worst consequences of global warming - including famines, wars, forced migration, etc, and the suffering and ultimately death that these will bring to hundreds of millions of human beings.

So, are you a moral human being first and (questionable) scientist second, or does your oversized ego take precedence? In the case of Ding and his nine(!) co-authors, it seems the latter.

"Science sans conscience n'est que ruine de l'âme." - Rabelais

Now, of course since they have already been published, they have legitimized the clearly false assertion that the year-round disappearance of Arctic sea ice which will occur over the coming few decades is mostly due to "natural climate variability". You could demonstrate that they are entirely wrong, de-construct all the fallacies in their tortuous reasoning, dissect their various logic mistakes, point to each and every dubious assumption they make in the paper, it wouldn't matter: they cannot be unpublished. And clearly, people with such an oversized ego are not going to retract themselves or even admit that they were wrong and wrote a piss-poor excuse of a climate science paper.
So there you have it.
Arctic sea ice is going to disappear over the coming years but now the takeaway from this man-made disaster is that it's mostly "natural climate variability". Crappy (un)science is the new normal.
Talk about improving communications between climate scientists and the general public!
Actually, I don't think they asserted most of the loss was from natural variation, and I suggest the philosophical discussion get moved to an appropriate thread.
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AndrewB

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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #87 on: March 20, 2017, 10:34:03 PM »
Actually, I don't think they asserted most of the loss was from natural variation, and I suggest the philosophical discussion get moved to an appropriate thread.
Hi jdallen,
From the abstract of the paper:
Our experiments indicate that the circulation trend may have contributed as much as 60% to
the decline of the September sea ice extent minimum since 1979.

Now, of course, the use of the word "experiments" is entirely wrong in the paper. Ding et al didn't perform any climate or Arctic sea ice experiment. They use the word "experiments" to describe their playing with two different models under 5 different sets of assumptions/data, hence the five "experiments" from which they derive their conclusion above.

Another problem with the abstract, and I am surprised that nobody has yet pointed it out here in this forum, is this idiotic statement:
A strengthening upper tropospheric anticyclonic anomaly over Greenland and the Arctic Ocean increased the downwelling longwave radiation above the ice by warming and moistening the lower Arctic troposphere.
So, none of the thousands of climate scientists who had previously worked - sometimes for decades - in the Arctic had ever guessed that warm, moist air was melting the sea ice. OK...

Do you really want to discuss the minutiae of how this climate science paper is total, utter crap, as Jim Williams intuited above? But then we are falling straight into the trap that this paper has setup for all the people who are concerned about reducing GHG emissions ASAP.

"Climate scientists can't even agree among themselves whether climate change (or how much of it) is the result of human activity."
"It's not settled science."
"CO2 is not the main driver of climate change."
"They were growing wheat in Greenland some centuries ago and nobody was any worse for it."
Etc.

AndrewB

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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #88 on: March 20, 2017, 11:33:07 PM »
AndrewB, welcome and thank you for putting it so concisely. To me argument 1 is still the most important, and I find the scientific claim highly questionable. The negative arctic sea ice trend is so obvious that attributing it to variable natural causes unrelated to AGW and GHGs using a model, probably means the model is not good enough.

Hi oren,
Thank you for your comment. Indeed the Ding et al paper makes the following claim, found in the abstract:
"Our experiments indicate that the circulation trend may have contributed as much as 60% to the decline of the September sea ice extent minimum since 1979. Because the observed circulation variability over the Arctic is inconsistent with the expected model response to anthropogenic forcing, a significant component of sea ice loss over the last three decades may have been driven by dynamical sources of natural climate variability."

And in their conclusion:
"The forcing of the summer sea ice by the trends in large-scale circulation, which are likely due mostly to natural variability, represents an important driver of the observed Arctic climate change."

They used two different models to reach these conclusions:
1) ECHAM5, an atmospheric general circulation model developed at the Max Planck Institute for Meteorology (see http://www.mpimet.mpg.de/en/science/models/echam/). Actually ECHAM5 is not intended for modeling Arctic sea ice, and has been superseded by ECHAM6. Why Ding et al chose to use an obsolete version of an atmospheric general circulation model beats me - unless they wanted a model that would best fit their foregone conclusions. The source code for ECHAM6 is freely available for lawful scientific use, and you can basically run the model on a properly configured desktop Linux workstation.
Now, even more puzzling is that the Max Planck Institute for Meteorology actually has a model specifically developed for modeling Arctic sea ice, see here (http://www.mpimet.mpg.de/en/science/the-ocean-in-the-earth-system/scientific-working-groups/sea-ice-in-the-earth-system/#c10229) and here (http://www.geosci-model-dev.net/9/3427/2016/gmd-9-3427-2016-discussion.html)
2) A global coupled ocean/sea-ice (POP2-CICE4) model, developed at UCAR (Ding). See http://www.cesm.ucar.edu/models/ for details. Obviously Ding is most familiar with POP2-CICE4.

The paper is lacking in that they don't quantify the skill of the models they used, they just claim they are "better" (actually they don't even use the word "skill", which is the proper technical term). I would suggest they used the models that "better" worked out to show their claim that sea ice decline is mostly the result of "natural climate variability". A clear example of manipulating your "experiment" to reach a desired conclusion.
« Last Edit: March 20, 2017, 11:55:25 PM by AndrewB »

Archimid

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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #89 on: March 21, 2017, 03:14:52 AM »

See Tamino's Analysis from October 2015. -snip-

To the proposed slowdown of the trend I say that extent is not a good measure for how much ice has been lost. I shouldn't used the monthly extent myself. Volume is a better measure of ice loss. Attached maximum and minimum Arctic Sea ice volume according to PIOMAS. I don't see a slowdown. I'm looking forward to Tamino's next look into the matter.
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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #90 on: March 21, 2017, 06:18:20 PM »
I don't see a slowdown. I'm looking forward to Tamino's next look into the matter.


The blue plot has the appearance of rough "cobbles" for most of it's plot. There's probably a good reason for that.

The red plot is more erratic and the biggest yearly drop is about 3500 cubic km but there's no section there to compare with the plot of the last 4 years.

How indicative is the dotted average line of what will actually happen in the next few years?

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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #91 on: March 21, 2017, 06:19:47 PM »

See Tamino's Analysis from October 2015. -snip-

To the proposed slowdown of the trend I say that extent is not a good measure for how much ice has been lost. I shouldn't used the monthly extent myself. Volume is a better measure of ice loss. Attached maximum and minimum Arctic Sea ice volume according to PIOMAS. I don't see a slowdown. I'm looking forward to Tamino's next look into the matter.

seconding that while the stats should be in percent in addition to just numbers because once we shall reach volumes below the current range between min and max the numbers will have to slow down while the percentage will accelerate. I hope that i was able to explain the thought in a comprehensive manner while perhaps someone else, a native english speaker, can/will do that better.
« Last Edit: March 21, 2017, 10:05:01 PM by magnamentis »
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Pragma

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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #92 on: March 21, 2017, 07:24:08 PM »
If I am reading the original graph correctly, it is not indicating a slowdown at all.

This is easy to misinterpret because it shows the anomaly on a yearly basis, which is still increasing.

So, while there appears to have been a sharper year-on-year increase previously, we are still at the maximum per year change.

Even if the graph were to completely flatten out, we would still be dropping per year at the maximum observed rate of ~ 750 k km^2

That said, I agree with others that extent is not the best way to evaluate things, due to wind and currents, as well as the theoretical possibility that we could have just a thin veneer of ice, and the extent would still stay the same.

Volume is the true measure. Unfortunately, there still seems to be a disturbing discrepancy between the various products.

Michael Hauber

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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #93 on: March 22, 2017, 06:45:56 AM »

To the proposed slowdown of the trend I say that extent is not a good measure for how much ice has been lost. I shouldn't used the monthly extent myself. Volume is a better measure of ice loss. Attached maximum and minimum Arctic Sea ice volume according to PIOMAS. I don't see a slowdown. I'm looking forward to Tamino's next look into the matter.

Looks to mirror the overall pattern for extent loss.  A faster period after 2000, and then a slower period in the last 5 or so years.  By itself I would hesitate to call anything other than random variation around a trend.  But it seems close enough to Tamino's extent analysis suggesting a non-trivial slow down to suggest the same applies to volume.  Also there were a few people extrapolating the short term trend up to about 2012 in volume to a 0 volume in 2016, and the recent years have clearly and significantly diverged from this extrapolation.  I remember taking these extrapolations quite seriously, and being puzzled by the fact that an extrapolation of extent suggested ice free in several decades and extrapolation of volume in several years.  Some people at that time seemed convinced by the idea that volume was more important than extent and so ice free in several years was the likely outcome.  They now look likely to be wrong, although a really big drop in Arctic ice to near 0 in the next few years would redeem this point of view and suggest that the old up was just a luck weather variation.
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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #94 on: March 22, 2017, 02:46:07 PM »
Surely the metric that really counts is total sea-ice mass.  Volume doesn't describe the quality/density of the ice any more than extent or area shows thickness.

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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #95 on: March 22, 2017, 02:48:08 PM »
If I am reading the original graph correctly, it is not indicating a slowdown at all.

This is easy to misinterpret because it shows the anomaly on a yearly basis, which is still increasing.

So, while there appears to have been a sharper year-on-year increase previously, we are still at the maximum per year change.

Even if the graph were to completely flatten out, we would still be dropping per year at the maximum observed rate of ~ 750 k km^2

If you're referring to Tamino's graph, I think it is showing the cumulative anomaly, not the rate of change. So an anomaly of -1 would mean 1 less than normal. not a rate of change of -1 per unit of time.

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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #96 on: March 22, 2017, 03:46:43 PM »
Surely the metric that really counts is total sea-ice mass.  Volume doesn't describe the quality/density of the ice any more than extent or area shows thickness.

I see Area/extent as a "compression" of volume. The compression allows for simpler understanding of some phenomena highly related to area at the cost of the information lost during the compression.

Volume and mass combine to give us density. Density is probably a very good indicator of actual ice conditions, however spatial information that volume provides is lost.

How useful knowing the Mass alone would be? I guess it will give the capacity of the ice to overcome waves, export and other physical interactions, but spatial information would be lost.
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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #97 on: March 22, 2017, 08:50:41 PM »
Surely the metric that really counts is total sea-ice mass.  Volume doesn't describe the quality/density of the ice any more than extent or area shows thickness.

I see Area/extent as a "compression" of volume. The compression allows for simpler understanding of some phenomena highly related to area at the cost of the information lost during the compression.

Volume and mass combine to give us density. Density is probably a very good indicator of actual ice conditions, however spatial information that volume provides is lost.

How useful knowing the Mass alone would be? I guess it will give the capacity of the ice to overcome waves, export and other physical interactions, but spatial information would be lost.

Actually, the metric being looked for is total energy required to melt -- and no, I do not know how to obtain that.

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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #98 on: March 22, 2017, 10:39:45 PM »
Re: energy to melt arctic ice

The Arctic floating icecap annually melts and refreezes aprroximately 20,000 Gigatons. If the ice were land based, this would correspond to a sea level rise and fall of 60 mm annually. The amount of heat involved  is close to the net  yearly radiative imbalance. Net Radiative imbalance from 1972-2008 due to greenhouse gases is  5.6e21 J/yr or about 183 Terawatt for the whole earth(Church,2011,  doi:10.1029/2011GL048794).

sidd

Jim Williams

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Re: Arctic sea ice changes: Natural variation vs human influence
« Reply #99 on: March 22, 2017, 11:18:20 PM »
Re: energy to melt arctic ice

The Arctic floating icecap annually melts and refreezes aprroximately 20,000 Gigatons. If the ice were land based, this would correspond to a sea level rise and fall of 60 mm annually. The amount of heat involved  is close to the net  yearly radiative imbalance. Net Radiative imbalance from 1972-2008 due to greenhouse gases is  5.6e21 J/yr or about 183 Terawatt for the whole earth(Church,2011,  doi:10.1029/2011GL048794).

sidd
Probably need to move this off into Stupid Questions or some such, but TheUAoB's original question "Surely the metric that really counts is total sea-ice mass.  Volume doesn't describe the quality/density of the ice any more than extent or area shows thickness" and your interesting reply has peaked my interest...so.

Do you think you can convert your cost to melt what is in fact melted into a cost to melt it all (either in Joules or Terawatts)?  It might also be interesting to do that as percentages of current mass and current excess heat.  Sort of a ball-park, how close are we really to a Blue Ocean Event?