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AbbottisGone

Wipneus,

Apparently half of the current sea level rise is natural. (I'll leave that unsourced for now as I simply wish to address this problem as if it were a given.) That means we should be seeing a fall in sea ice anyway.

The problem then simply becomes how fast is too fast. (A problem well defined is half solved!!)

Where do we get the information on rates of change of this fall?

Is this all answered by the (careful) use of the exponential trend graphs you have put together over the years? (All graphs must be interpreted carefully!)

Cheers,

(I'm obviously guessing yes and am infact in mid-conversation with Jim about it,.. well,.. I noticed your graph on his page and started asking lots of questions again lol!)

Neven
Apparently half of the current sea level rise is natural. (I'll leave that unsourced for now as I simply wish to address this problem as if it were a given.) That means we should be seeing a fall in sea ice anyway.

Excuse me? How does a rise in sea level relate to a fall in sea ice?

Where do we get the information on rates of change of this fall?

We get the data and put it in a spreadsheet.

Wipneus
Wipneus, Apparently half of the current sea level rise is natural.

You have already lost me there, and it does not get better further.

I am always happy to explain and discuss what I wrote, but here I have no idea what you mean.

D

Fish here.

The melting of mountain glaciers, caused by black carbon before temperatures warmed, in Europe and Asia has contributed to sea level rise. That was anything but natural.

The claim that half of *global* sea level rise is natural is not supported by scientific evidence. It may be true at individual measurement sites, e.g. Virginia Beach, where there is natural subsidence.

Wipneus

my CT-like calculation results for today

(NH, SH, global)

2016.1452 -113.6 12.447126 -33.0 1.774587 -146.5 14.221713
2016.1479 +33.4 12.480547 -4.7 1.769923 +28.8 14.250470
2016.1507 +138.5 12.619037 +37.2 1.807087 +175.7 14.426124
2016.1534 +135.3 12.754380 -14.3 1.792812 +121.1 14.547192

All calculated from today's NSIDC sea ice concentration data and only occasionally differ more than a few k from the final values released by Cryosphere Today.

Jim Hunt

Snow White sends Wipneus a big kiss.

Her free of charge prediction to the Director of the Global Warming Policy Forum proved to be extraordinarily accurate:

http://GreatWhiteCon.info/2016/02/global-sea-ice-area-at-lowest-ever-level/#comment-213591

Yet another new “lowest *ever” Cryosphere Today global sea ice area of 14.221 million square kilometers.

Neven

2016.1507 +138.5
2016.1534 +135.3

Well, that blows the preliminary peak out of the water. No record early Arctic sea ice Max for CT this year! Still 390K below the 2011 record max though.

Wipneus

my CT-like calculation results for today

(NH, SH, global)

2016.1479 +33.4 12.480547 -4.7 1.769923 +28.8 14.250470
2016.1507 +138.5 12.619037 +37.2 1.807087 +175.7 14.426124
2016.1534 +135.7 12.754770 -14.3 1.792812 +121.5 14.547582
2016.1562 +89.7 12.844477 +6.9 1.799745 +96.6 14.644222

All calculated from today's NSIDC sea ice concentration data and only occasionally differ more than a few k from the final values released by Cryosphere Today.

Neven

Another big increase, but still 300K below the 2011 record. If CT SIA starts going down again I will post my blog post discussing the max. JAXA didn't report today. Maybe they want to check yesterday's big increase.

Rob Dekker

Looking at IJIS' ice extent graph :
https://ads.nipr.ac.jp/vishop/vishop-extent.html?N
it looks to me that 2016 is showing a "last resort" rebound, similar to what happened in 2012.

Interesting is that DMI's "north-of-80" temp graph still shows a remarkably "warm" Arctic :
http://ocean.dmi.dk/arctic/meant80n.uk.php
which suggests that ice volume growth at this point will be marginal.

I thus still expect the next PIOMAS update to show that sea ice volume is at an all-time low for the date..

Kris

Neven wrote

JAXA didn't report today.

Neither did NSIDC (for what is the day before yesterday now). Likely rather some communication problem.

Meanwhile, for that day before yesterday [25th], JAXA registered 13,88 millions km2 (a big uptick), and for yesterday [26th] 13,86 km2, a small 'downtick'.

AbbottisGone

Me: Apparently half of the current sea level rise is natural. (I'll leave that unsourced for now as I simply wish to address this problem as if it were a given.) That means we should be seeing a fall in sea ice anyway.

Neven: Excuse me? How does a rise in sea level relate to a fall in sea ice?
<<
Indirectly.

I'm correlating. Perhaps this is otherwise known as being a little too indirect and that can't help the communication of things so I apologise and shall be more careful in the future.

We are coming out of an ice age and so we expect to see some natural level of sea level rise and some natural level of sea ice shrinkage don't we?

Maybe I'm wrong starting with this as assumption.

AbbottisGone

Me: Wipneus, Apparently half of the current sea level rise is natural.

Wipneus: You have already lost me there, and it does not get better further.

I am always happy to explain and discuss what I wrote, but here I have no idea what you mean.
<<

I am looking at correlation. Even if the statistics are not directly related I assume they are indirectly related. They are both indicators of climate change and the question really comes down to which one is better?

Which statistical indicator/s is/are the market/s going to act on, for instance,.. and which should mankind be most concerned about? (For we are the markets!)

All these forums are discussing is which indicators are the ones we need to be watching!

..when will the markets panic and on what grounds? It will be because of an indicator of some kind but which one is the most relevant and what will be the signal that it gives to make it the most relevant.

I suspect it is the exponential trends analysis of sea ice that will give us the heads up before sea level rise statistics do... unless of course someone has done an exponential trends analysis of sea level rise of course. (Huh, didn't think of that now did I!)

[..scratches head]

AbbottisGone

@ D,

Surely you are talking of a relatively insignificant event?

Neven
We are coming out of an ice age and so we expect to see some natural level of sea level rise and some natural level of sea ice shrinkage don't we?

Yes, for the SLR, for sea ice I'm not so sure. It was around these levels during the Holocene Climatic Optimum, maybe even lower, and then increased again (as temperatures went down, see this graph, for instance).

As for coming out of an ice age, I believe there are scientists who claim we would be entering into one if it weren't for all the extra GHGs.

Wipneus

my CT-like calculation results for today

(NH, SH, global)

2016.1507 +138.5 12.619037 +37.2 1.807087 +175.7 14.426124
2016.1534 +135.7 12.754770 -14.3 1.792812 +121.5 14.547582
2016.1562 +89.4 12.844204 +6.9 1.799745 +96.4 14.643949
2016.1589 -66.2 12.777960 -6.1 1.793637 -72.4 14.571597

All calculated from today's NSIDC sea ice concentration data and only occasionally differ more than a few k from the final values released by Cryosphere Today.

AbbottisGone

Ok, so no direct correlation should be assumed between sea ice and sea level because historically it just didn't work like that.

Does that then become the curious fact of our times? IS THIS THE INDICATOR that has the science worlds heckles in a bunch??

D_C_S

AbbottisGone: If an ice cube is floating in a glass of water, the amount of water that it displaces has the same mass as the ice cube. If the ice cube melts, it then still has that same mass, so it still displaces the same amount of water, but after it melts it precisely fills that volume, because then it has the same density as the other water in the glass. So there would not be a change in the water level in the glass from the ice cube melting, assuming that the temperature of the water is constant, say at O C.

AbbottisGone

thankyou D_C_S but we are talking about how indirectly the statistics are related.

Kris

As an hors-d'oeuvre at the coming melt season, enjoy the large polinia in front of Barrow.

Also clearly detectable at the Uni-Bremen chart.

Jim Hunt

Also clearly detectable on the ASIF quite some time ago:

http://forum.arctic-sea-ice.net/index.php/topic,1377.msg70155.html#msg70155

Wipneus

my CT-like calculation results for today

(NH, SH, global)

2016.1534 +135.7 12.754770 -14.3 1.792812 +121.5 14.547582
2016.1562 +89.5 12.844304 +6.9 1.799745 +96.5 14.644049
2016.1589 -67.6 12.776749 -9.8 1.789907 -77.4 14.566656
2016.1616 -35.6 12.741170 +9.6 1.799485 -26.0 14.540655

All calculated from today's NSIDC sea ice concentration data and only occasionally differ more than a few k from the final values released by Cryosphere Today.

Bill Fothergill

@ AiG

" ... They are both indicators of climate change and the question really comes down to which one is better? ... "

Although it's nice to be able to boil things down (perhaps I should have used a different expression?) to a single number that can be held up as the gold standard, things are not that simple.

If you are one of the billion or so people that live with spitting distance of the oceans, then SLR is a pretty meaningful concept. On the other hand, if you are a subsistence farmer trying to eke out a meagre living in sub-Saharan Africa, then SLR doesn't matter a toss, but temperatures, and more specifically monsoon reliability is the crux upon which both your livelihood and your very life depend.

Regarding historic SLR since the beginning of the Holocene, it was pretty damn fast until about 5,000 years ago, owing to the demise of the Laurentide and Fenno-Scandian Ice Sheets. However, after these had melted out close to the time of the Thermal Optimum, SLR did not do a great deal.

An example of some of the reconstruction work can be found here...
http://www.whoi.edu/cms/files/Kemp2013QSR_170144.pdf

Yes, I know it's based on the Jersey shore, but you can find lot's of material on this. What is a bit more difficult to find is anything that substantiates your suggestion that about half of current SLR rate is "natural". If you have a meaningful source, I would be interested to learn of it.

Please note that early 20th century SLR rates of 1.7 or 1.8 mm/year cannot simply be written off as "natural".

Thanks to the precessional cycle, at the beginning of the Holocene, the Northern Hemisphere summer solstice occurred pretty damn close to perihelion. At that time, the earth's obliquity was also considerably greater than its present value of 23.4 degrees. (I think it would have been a little over 24 degrees at the time.) The eccentricity of the Earth's orbit has also been reducing over this period.

The present state of our precessional, obliquity and eccentricity cycles should be pushing us back towards glaciation.

AbbottisGone

..thanks Bill, much food for thought.

My MO is really about trying to see the linearity that no one wants to see. If it's not there then I appreciate everyone telling me that's it's not there.

As for my assertion about sea level rise basically I read it somewhere(aka a little birdy told me) and if I can find the reference I will post it... it was only a few days ago so perhaps I should be able to find it. The point was not to get bogged down in references but look at the following questions.... the fact those numbers seems contentious gives me more impetus for , I dunno, some kind of attack on the problem at hand so cheers.

Anway,... looking at the 2015 arctic sea ices' weird journey to maximum I couldn't help but wonder if el nino presents itself before it's offically called.

[... just thinking out loud.]

[..also I'll go through your links in time, cheers!]

Rob Dekker

AbbottisGone said


Apparently half of the current sea level rise is natural. (I'll leave that unsourced for now

Yes. That is the second time that you leave that quote unsourced.

Rob Dekker

AbbottisGone said


As for my assertion about sea level rise basically I read it somewhere(aka a little birdy told me) and if I can find the reference I will post it... it was only a few days ago so perhaps I should be able to find it.

Anxiously looking forward to your evidence.

AbbottisGone

I'm starting to wonder if I heard it on FOXTEL..

Wipneus

my CT-like calculation results for today

(NH, SH, global)

2016.1562 +89.5 12.844304 +6.9 1.799745 +96.5 14.644049
2016.1589 -67.6 12.776749 -9.8 1.789907 -77.4 14.566656
2016.1616 -35.4 12.741300 +9.6 1.799485 -25.9 14.540785
2016.1644 +9.7 12.750993 -5.7 1.793830 +4.0 14.544823

All calculated from today's NSIDC sea ice concentration data and only occasionally differ more than a few k from the final values released by Cryosphere Today.
I can also be wrong in the first column when CT reports the results for 29 Feb and later. I'll fix it some time if needed.

DavidR

The weather maps are suggesting that we will see a big increase in extent over the next week. It appears to be the best conditions for both the formation and dispersal of ice with winds mainly from the north and temperatures lower than they have been for several weeks.

Most of the increase is likely to be in the Bering which has its first real cold spell in a couple of months. The Atlantic gets a couple of strong low pressure systems that usually mean no real nett gain, but the temperature anomaly drops right down.

Bill Fothergill

@ AiG

RE: Sea Level Rise

When I responded earlier, I meant to include a link to this NASA article about SLR during the Holocene ...

http://www.giss.nasa.gov/research/briefs/gornitz_09/

Wipneus

my CT-like calculation results for today

(NH, SH, global)

2016.1589 -67.6 12.776749 -9.8 1.789907 -77.4 14.566656
2016.1616 -35.4 12.741300 +9.6 1.799485 -25.9 14.540785
2016.1644 +9.7 12.750962 -5.7 1.793830 +4.0 14.544792
2016.1671 +15.4 12.766372 +9.0 1.802850 +24.4 14.569222

All calculated from today's NSIDC sea ice concentration data and only occasionally differ more than a few k from the final values released by Cryosphere Today.
I can also be wrong in the first column when CT reports the results for 29 Feb and later. I'll fix it some time if needed.

Bill Fothergill

If someone accidentally cuts them self with a blade, the wound could be deep, or long, or both.

A similar kind of analogy can be made as regards the CT global SIA minimum. Prior to this year, 2006 and, to a lesser extent, 2011 had SIA minimums that were both deep and long.

As we all know, 2016 has gone deep, with the previous record low minimum being surpassed on no fewer than 12 occasions. However, it's starting to get long, as well as deep. The latest officially published data on CT is dated 2016.1589, and at that date, the 100 lowest daily values in the CT global dataset are spread as follows ...

2006 38 days
2007 04 days
2011 23 days
2016 35 days

With the inclusion of those next 3 days worth of data kindly supplied by Wipneus (see above), those first three years will each undergo a single decrement. By that time, 2016 will have risen to 38 days in the lowest 100, and, by that metric, will once again surpass 2006.

Neven
The weather maps are suggesting that we will see a big increase in extent over the next week. It appears to be the best conditions for both the formation and dispersal of ice with winds mainly from the north and temperatures lower than they have been for several weeks.

Most of the increase is likely to be in the Bering which has its first real cold spell in a couple of months.

Indeed, David, the forecast has become more likely (and my feeling is that it's somehow more correct during winter). The Bering has quite some late-freezing potential of at least 200K. This might thwart this year's record attempt for CT SIA as well (SIE is already out of the running).

Wipneus

my CT-like calculation results for today

(NH, SH, global)
2016.1616 -35.4 12.741300 +9.6 1.799485 -25.9 14.540785
2016.1644 +9.7 12.750962 -5.7 1.793830 +4.0 14.544792
2016.1671 +15.6 12.766578 +9.0 1.802850 +24.6 14.569428
2016.1699 -52.2 12.714382 +11.9 1.814750 -40.3 14.529132

All calculated from today's NSIDC sea ice concentration data and only occasionally differ more than a few k from the final values released by Cryosphere Today.
I may also be wrong in the first column when CT reports the results for 29 Feb and later. I'll fix it some time if needed.

John Christensen

While the AO and Bering seem to indicate further increase, a low has crept up along the Norwegian west coast and has reached Svalbard providing winds from the south in Barents and high temperatures, which will keep ice extent down in both this area and the Atlantic part of the central Arctic Ocean, so I would expect area and extent to stay flat, at best, for the next few days.

Wipneus

my CT-like calculation results for today

(NH, SH, global)
2016.1644 +9.7 12.750962 -5.7 1.793830 +4.0 14.544792
2016.1671 +15.6 12.766578 +9.0 1.802850 +24.6 14.569428
2016.1699 -52.3 12.714314 +11.9 1.814750 -40.4 14.529064
2016.1726 -22.5 12.691812 -6.2 1.808553 -28.7 14.500365

All calculated from today's NSIDC sea ice concentration data and only occasionally differ more than a few k from the final values released by Cryosphere Today.
The first column is wrong (not like CT), starting at 1st of March, which CT has given the same "date" as 29th of February (making it quite useless).
I'll fix that one of these days.

Wipneus

my CT-like calculation results for today

(NH, SH, global)
2016.1671 +15.6 12.766578 +9.0 1.802850 +24.6 14.569428
2016.1699 -52.3 12.714314 +11.9 1.814750 -40.4 14.529064
2016.1726 -22.3 12.692058 -6.2 1.808553 -28.5 14.500611
2016.1753 +54.2 12.746250 +48.1 1.856618 +102.3 14.602868

All calculated from today's NSIDC sea ice concentration data and only occasionally differ more than a few k from the final values released by Cryosphere Today.
The first column is wrong (not like CT), starting at 1st of March, which CT has given the same "date" as 29th of February (making it quite useless).
I'll fix that one of these days.

Wayne Kernochan

Forwarding ThinkProgress article on Arctic sea ice (and also testing if my Typepad words after about a month of difficulties) -- http://thinkprogress.org/climate/2016/03/01/3754891/arctic-sea-ice-growth/

Rob Dekker

Re: sea level rise :
We all know that based on simple physics, sea ice does not cause sea level rise. Now, you can still argue that the effect is "indirect", because higher temperatures in the Arctic cause BOTH a reduction in sea ice AND sea level rise due to melting ice sheets.

In that respect, a new scientific paper has been presented (Kopp et al 2016) which argues that sea level rise in the 20th century is unprecedented at least over the past 2500 years :
http://www.realclimate.org/index.php/archives/2016/02/millennia-of-sea-level-change

Wipneus

my CT-like calculation results for today

(NH, SH, global)
2016.1671 -52.3 12.714314 +11.9 1.814750 -40.4 14.529064
2016.1699 -22.3 12.692058 -6.2 1.808553 -28.5 14.500611
2016.1726 +54.7 12.746719 +48.1 1.856618 +102.7 14.603337
2016.1753 -21.1 12.725594 +37.0 1.893617 +15.9 14.619211

All calculated from today's NSIDC sea ice concentration data and only occasionally differ more than a few k from the final values released by Cryosphere Today.

Wipneus


my CT-like calculation results for today

(NH, SH, global)
2016.1699 -22.3 12.692058 -6.2 1.808553 -28.5 14.500611
2016.1726 +54.7 12.746719 +48.1 1.856618 +102.7 14.603337
2016.1753 -21.3 12.725438 +37.0 1.893617 +15.7 14.619055
2016.1781 -2.0 12.723470 +66.5 1.960082 +64.5 14.683552

All calculated from today's NSIDC sea ice concentration data and only occasionally differ more than a few k from the final values released by Cryosphere Today.

The freezing in the SH now well on its way, NH may linger a bit longer around its max, so the global minimum is not likely to change anymore anymore. These CT predictions will go into hibernation for now.

Neven

Thanks, Wipneus! I hope you'll provide your 'CT predictions' on the upcoming max blog post.

John Christensen

Hi Neven,

Not sure which thread to use, but given the drops in Okhotsk and Bering I would think you could safely call the CT NH area max by now.

Jim Hunt

That's what I thought too John!

https://twitter.com/GreatWhiteCon/status/709898232676147200

However a lot of "sea ice" has suddenly appeared in the St. Lawrence. See Wipneus' latest at:

http://forum.arctic-sea-ice.net/index.php/topic,1457.msg72175.html#msg72175

Neven
Not sure which thread to use, but given the drops in Okhotsk and Bering I would think you could safely call the CT NH area max by now.

John, you can use the Mad Max blog post, and no, I'm not calling it. JAXA is just 32K below the preliminary peak, and Wipneus says CT SIA will get closer to its prelimpeak too.

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