2018 Sea Ice Thread

Arctic sea ice volume by Dec 31st: 14,418 km3

More than 1,300 km3 above it value the year before, and 500 km3 above that of the end of 2012. Yet, it's lower than any other value to date and way below the typical value when the century began, some 20,000 km3.

It doesn't sound that much, but we're now much closer to the year's maximum (to happen during April) than its minimum.
 
I remind you what is linked in the OP

This is a thread on Arctic and Antarctic Sea Ice for tracking sea ice over the course of the 2018.

This thread is approved by the moderator team for the limited purposes described, anything more than incidentally beyond that may be subject to moderator action.

Rules:

1. This is not an AGW thread.
2. This is about Sea Ice only.
3. You may speculate on the trajectory of Sea Ice melting in here.
4. You may post data from official sources and news articles from the science press in this thread (related to the thread's topic, of course)
5. No politics.
6. See rule 5.
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I wonder what the changes in Decadal AMO and PDO will bring to the ice cover in the north,


“We found that the winter climate over East Asia was statistically significant warmer than normal when the ENSO-like mode and AMO were positively in phase. In such cases, the Siberian high was generally significantly weakened and anomalous anticyclones emerged over the western North Pacific,” said Dr. HAO.

“The reverse patterns occurred when the ENSO-like mode and AMO both were in negative phase. In contrast, when the ENSO-like and AMO were out of phase, the anomalies related to the EAWM tended to exhibit relatively weaker features,” he said.
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https://phys.org/news/2017-04-scientists-unravel-effect-enso-atlantic.html


Possible connections of the opposite trends in Arctic and Antarctic sea-ice cover
Lejiang Yu,a,1,2,3 Shiyuan Zhong,3 Julie A. Winkler,3 Mingyu Zhou,1,4 Donald H. Lenschow,5 Bingrui Li,1,2 Xianqiao Wang,4 and Qinghua Yang4
Author information ► Article notes ► Copyright and License information ►
Go to:
Abstract
Sea ice is an important component of the global climate system and a key indicator of climate change. A decreasing trend in Arctic sea-ice concentration is evident in recent years, whereas Antarctic sea-ice concentration exhibits a generally increasing trend. Various studies have investigated the underlying causes of the observed trends for each region, but possible linkages between the regional trends have not been studied. Here, we hypothesize that the opposite trends in Arctic and Antarctic sea-ice concentration may be linked, at least partially, through interdecadal variability of the Pacific Decadal Oscillation (PDO) and the Atlantic Multidecadal Oscillation (AMO). Although evaluation of this hypothesis is constrained by the limitations of the sea-ice cover record, preliminary statistical analyses of one short-term and two long-term time series of observed and reanalysis sea-ice concentrations data suggest the possibility of the hypothesized linkages. For all three data sets, the leading mode of variability of global sea-ice concentration is positively correlated with the AMO and negatively correlated with the PDO. Two wave trains related to the PDO and the AMO appear to produce anomalous surface-air temperature and low-level wind fields in the two polar regions that contribute to the opposite changes in sea-ice concentration.
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continues
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5381096/

Yet with record low ice cover on both ends maybe the teeter totter is breaking down.

I have not been reading much on the low Antartic cover....has an explanation been proposed?
 
macdoc said:
...

Yet with record low ice cover on both ends maybe the teeter totter is breaking down.

I have not been reading much on the low Antartic cover....has an explanation been proposed?
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I would safely say it's broken from recent years on.

The reason for the slight seasonal growth in previous decades is complex. One factor is the ozone hole -ozone is a greenhouse gas- so the upper atmosphere cooled so strengthening the circumpolar winds. That changed the pattern of low pressures, and those stronger and variable winds brought pieces of ice together and propelled them into higher latitudes. A lattice like pattern in ice is the consequence, where polynyas -patches of open water surrounded by ice- increased, fostering the formation of new ice.

Such a sum of causes couldn't overcome the general warming pattern in the region, so the increase in ice is almost inconsequential, ten times or more weaker than the pattern of losses in the northern hemisphere.

That's why they created this official Trump-like graphic

arc_antarc_1979_2012.png


which is a master piece of deception even if it's strictly true [see my debunking here, here]
 
By the way, an update

Arctic sea ice is now at its record low for a January. It's headed to a record low maximum, probably under 14 million square kilometres for the first time in modern times.

Antarctic sea ice stands now as the second record low for a January, only 18,000 km2 above last year's absolute record. It's not clear what's going to happen, it depends on the weather during the next 3 or 4 weeks, but the southern sea ice, now below the 3 million square kilometres mark, may end being one of the five lowest values for the melting season. A record breaking low is not out of the picture. In two weeks it'll become clearer.
 
NSIDC's Antarctic sea ice trend for every month in the year. Buckle up!

December '17 ------ +1.3% +/- 2.1% per decade
November '17 ------ +0.2% +/- 0.9%
October '17 ------- +0.8% +/- 0.6%
September '17 ----- +0.7% +/- 0.7%
August '17 -------- + 0.6% +/- 0.5%
July '17 ----------- +0.9% +/- 0.6%
June '17 ---------- +1.3% +/- 0.6%
May '17 ----------- +2.0% +/- 0.6%
April '17 ----------- +2.9% +/- 2.6%
March '17 --------- +3.3% +/- 3.8%
February '17 ------ +3.0% +/- 3.8%
January '17 ------- +3.5% +/- 4.2%

So, there's an overall increasing trend with some probability around 12% of it being indeed a decreasing trend :D

And certainly this month confirms a dropping increasing trend from its +5.3% +/- 4.3% on January 2015 to some +3.0% +/- 4% this January, increasing the likelihood it's already a decreasing trend in sea ice (tongue twister)

Unlike the Northern Hemisphere's, this trend would have deeper consequences, as the effective increase of albedo in southern latitudes is more consequential because of the months and latitudes it takes place.

Some years into the future, I think the complete demise of the Antarctic sea ice during February and March will occur before the demise of its arctic counterpart during August and September (let's say less that a quarter million square kilometres is "no ice")
 
The Antarctic sea ice extent is today just 300,000 km2 above its lowest value on record. It has been losing some 50 to 60 thousand square kilometres a day, even the last 24 hours, and the record low for every year happens not earlier than February 15th and can be as late as March 7th, so ... do the math. A little early to announce it but we're on record breaking territory.

I trust the myth of one polar region compensating the other one is going into the category of "past anecdotes and tricks" together with "the urban heat islands" and other real or imaginary elements used to make people believe it wasn't happening what indeed has been happening.
 
aleCcowaN said:
........ the category of "past anecdotes and tricks" together with "the urban heat islands"........
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Huh? This really is a thing. If you don't think it's on topic in here, I'd join in a new thread on the subject.
 
MikeG said:
Huh? This really is a thing. If you don't think it's on topic in here, I'd join in a new thread on the subject.
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I think the reference is to the common denier claim that urban heat islands are the real reason why surface temperatures appear to have risen (because the areas where thermometers are placed have become more urbanised and hence warmer). I haven't seen it much recently, but it was certainly a popular piece of denier nonsense at one time.
 
Pixel42 said:
I think the reference is to the common denier claim that urban heat islands are the real reason why surface temperatures appear to have risen (because the areas where thermometers are placed have become more urbanised and hence warmer). I haven't seen it much recently, but it was certainly a popular piece of denier nonsense at one time.
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^That
 
Stay tuned. We're close to twin records: record low yearly Arctic maximum sea ice extent, and 70,000 km2 away from a record breaking low in Antarctic sea ice extent, for second year in a row. Not quite there, but almost...

One thing is sure: this quarter we are having a record breaking polar sea ice extent negative anomaly, of about 2 million square kilometres and some 3 million square kilometres less than the typical values in the early 80s.
 
aleCcowaN said:
Stay tuned. We're close to twin records: record low yearly Arctic maximum sea ice extent, and 70,000 km2 away from a record breaking low in Antarctic sea ice extent, for second year in a row. Not quite there, but almost...

One thing is sure: this quarter we are having a record breaking polar sea ice extent negative anomaly, of about 2 million square kilometres and some 3 million square kilometres less than the typical values in the early 80s.
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I'm really grateful for these threads and the expertise you share within them!
 
Mikemcc said:
Holy crap, this curve is absurd!

https://nsidc.org/data/seaice_index/images/daily_images/N_stddev_timeseries.png
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This is a continuation of the trend. The last six years (2012 - 2017 + 2018) have all been way below average for the years 1979 - 2006. See my link below for the graph. Much more informative than in the previous post I have just quoted.

http://web.nersc.no/WebData/arctic-roos.org/observation/ssmi1_ice_ext.png

For completness see also http://arctic-roos.org/observations/ice-area-and-extent-in-arctic
 
rjh01 said:
Mikemcc said:
Holy crap, this curve is absurd!

https://nsidc.org/data/seaice_index/images/daily_images/N_stddev_timeseries.png
Click to expand...

This is a continuation of the trend. The last six years (2012 - 2017 + 2018) have all been way below average for the years 1979 - 2006. See my link below for the graph. Much more informative than in the previous post I have just quoted.

http://web.nersc.no/WebData/arctic-roos.org/observation/ssmi1_ice_ext.png

For completness see also http://arctic-roos.org/observations/ice-area-and-extent-in-arctic
Click to expand...

An the cause is in the figure here.
 
On February 20th the Antarctic sea ice extent reached an early annual minimum of 2.181 million square kilometres, above the 2.106 mark during last year (the absolute minimum on record) but below the 2.29 from 1997, which had been the lowest on record until a year ago.

That date, the Antarctic sea ice anomaly was -637,000 km2, what together with an Arctic sea ice anomaly of -1,480,000 km2 makes for a global sea ice anomaly of -2.117 millions square kilometres, what places us in record breaking ice anomaly for the first quarter of the year (anomalies can be 1 million km2 larger by Q3, when the Arctic sea ice reach its yearly minimum).

In a few days, with the yearly Arctic maximum extent and the sea ice volume by February 28th we'll have a clearer hint about how this year's northern summer is gonna be.
 
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