2015/2016 Winter analysis

I think this winter is going to get studied like crazy,
for quite a while. It’s a very interesting time.
        Jennifer Francis, Washington Post

The extraordinary temperature anomalies in the Arctic since the start of the year haven't gone unnoticed in quite a few media outlets, and I apologize for not having joined the fray of actuality. On the other hand, context trumps actuality, as we need to compare to previous years and get a feel for what this prelude to the melting season may mean. In that sense, I'm early with this year's winter analysis (compared to last year).

Let's start studying like crazy, shall we?

It's a lot of text and images, so if you're feeling a bit tl;dr-ish today,
skip to the conclusion at the bottom of the page.

Surface air temperature

Here are the monthly temperature graphs for November-February in the Arctic Circle, from 2005/2006 to the past winter, based on the NCEP reanalysis dataset:

Last November saw the highest average monthly temperature in the 2005-2015 record, followed by a lower December, relatively speaking. Things then get a little bit crazy after the turn of the year, with the January 2014 record getting broken by almost 3 °C! February isn't far behind either, almost 1.5 °C higher than the already 'warm' February of 2014. This is unprecedented.

To see where temps were least low, I've created average temperature maps using the Daily mean composites page from NOAA's Earth Science Research Laboratory website, comparing the 2015/2016 freezing season to those preceding the years with the lowest minimums on record (click for a larger version):

 

The right hand corner of this overview really jumps out at you, doesn't it? The red blob of 5+ °C temperature anomalies that covers the entire Arctic Ocean during January is simply astounding. And again, February isn't far behind. Nothing comes close to it, really.

I found this image in the 2013/2014 Winter analysis blog post that shows what January and February 2014 - number 2 on the temperature graphs - looked like, a bit closer than other years, but still not that close:

Sea level pressure and ice drift

I've also created monthly average sea level pressure maps, as these tell us something about how cloudy the Arctic has been and which way the winds have been blowing, again compared to the freezing seasons preceding the years with the lowest minimums on record:

This year's SLP maps look quite similar to those of previous years, except perhaps for February which shows a bright, red dot of high pressure, indicating an active Beaufort Gyre which should cause ice transport through Fram Strait. This seems to be confirmed by this IFREMER/CERSAT sea ice drift map for February, with arrows clearly showing a textbook example of a strong Beaufort Gyre and Transpolar Drift Stream:

This movement caused another cracking event in the Beaufort Sea that I discussed in this blog post last month. We won't know what the effect of this cracking will be, as the 2013 cracking event seemed to reinforce the ice pack on the Pacific side of the Arctic, although it happened a couple of weeks earlier, during the height of winter.

Here's a glimpse of the cracking event, an AVHRR image provided by Environment Canada:

Ice age

Speaking of radar images, here's the latest ASCAT image for day 86 (March 26th), compared to those of 2012, 2013 and last year:

Here's how these images should to be interpreted, according to the NSIDC:

The ASCAT sensor measures the radar–frequency reflection brightness of the sea ice at a few kilometers resolution. Sea ice radar reflectivity is sensitive to the roughness of the ice and the presence of saltwater droplets within newer ice (and, later in the season, the presence of surface melt). Thus older and more deformed multiyear ice appears white or light grey (more reflection), whereas younger, first-year ice looks dark grey and/or black.

There's definitely less bright white compared to last year, but overall things look slightly whiter than the situation preceding and following the 2012 record setting melting season. What sets this year apart from the other years, is a large patch of whitish ice on the Atlantic side of the Arctic. If that ice is indeed thicker, it could be poised to be transported through Fram Strait, depending on the winds.

Here are the AARI ice age maps for the end of March that show the amount of multi-year ice (MYI) in the Arctic (brown colour):

I'm surprised AARI is showing so little MYI in the Beaufort Sea towards the Chukchi, but the map for this year seems to confirm there's more MYI is surrounding the North Pole, almost entirely filling the entire 85-90N region.

Unfortunately, the well-known Tschudi/Maslanik/Fowler ice age maps that are used by the NSIDC for their reports are being overhauled, so I can't make any comparison. However, I did find some images running up to the first week of 2016, and I have to say they look very appealing visually (not that the old ones didn't). Here's the animation:

So, that ice on the Atlantic side of the Arctic seems to be second-year ice, in other words first-year ice that managed to survive last year's melting season. This makes sense as the ice pack there didn't have to suffer the double whammy of clear skies and high temperatures that it did on the Pacific side of the Arctic.

Ice volume and thickness

I have some more sources of info that give an idea of the current situation, as compared to previous years. Every month Wipneus makes interesting sea ice thickness distribution maps, based on PIOMAS data, which he posts in this Arctic Sea Ice Forum thread. These maps show the difference between the most recent monthly average and that of a previous year. Below is the difference between February 2016 and the same month in 2011, 2012, 2013 and 2015 (red means there's more ice now than then, blue means there's less ice now than then):

Just like the AARI ice age maps, these thickness comparison maps seem to imply that this year's ice on the Pacific side of the Arctic is thinner than it was in previous years, which may mean there is no barrier of thicker, older ice to protect the ice in the Central Arctic Basin. At the same time the ice is thicker on the Siberian side, according to PIOMAS.

It's good to remember that this is modelled data, not observations, and so we can't be sure about regional thickness. PIOMAS volume data for the Arctic as a whole, however, has been one of our best tools over the past years to assess conditions on the Arctic, and as I wrote a few weeks back in the March PIOMAS update, the increase in sea ice volume so far this year is the lowest on record:

The only direct observations of sea ice thickness we have, is provided by ESA's CryoSat-2 satellite. Although the archive is a bit of a mess, we still should be grateful that the Centre for Polar Observation and Modelling (University College of London) provides near real-time images. This data isn't perfect either, as it's very difficult to measure sea ice thickness, but below I compare thickness for the past 28 days to that of MarApr/Spring 2012 and 2013, and Apr9-May15 2015 (mind you, the ice will get slightly thicker as the volume max is reached mid-April):

These images also seem to confirm that the ice on the Pacific side is somewhat thinner than it was in previous years (more blue spots) and a significant part of the thicker ice is positioned right in front of the Fram Strait exit.

Snow cover

This analysis ends with an appraisal of Northern Hemisphere snow cover conditions, as these can also play a role in how a melting season develops.

Things didn't look all that great during February, but have improved somewhat recently as can be seen on this graph provided by NOAA STAR (Global Multisensor Automated Snow and Ice mapping system):

Here are the monthly anomaly maps from Rutgers Snow Lab for December, January and February:

Conclusion

Spring has come, light is slowly returning to the Arctic that has just experienced its warmest or least coldest winter on record. As suggested by the latest PIOMAS data, we have returned to similar initial sea ice conditions preceding the melting seasons of 2011 and 2012. This basically means that this melting season will get a shot at the record. It isn't a sure shot, of course, as there is no (direct) correlation between winter and summer sea ice conditions.

The Pacific side of the Arctic seems to be especially vulnerable this year, but maybe/hopefully the recent cracking event can help thicken the ice some more over there by letting the heat escape from the water (as presumably happened in 2013). At the same time, over on the Atlantic side of the Arctic, a lot of the second-year ice that survived last year's melting season is perfectly positioned for export through Fram Strait. And will the Northwest Passage and Northern Sea Route open up again, as they have done so many times in the past decade?

It's a cliché, but in the end the weather will determine this melting season's outcome. We'll now observe what changes occur during the transition time between winter and spring, until in a month or so that crucial first phase of the melting season starts, when melt ponds slowly start to form, which determines how much melting momentum is built up for the remainder of the melting season.

Looking forward to watching how things will unfold, here and on the Arctic Sea Ice Forum (here's the https version, ignore warning).

Comments

[Colorado Bob]

Excellent work Neven.

[Neven]

Thanks, CB!

[Colorado Bob]

Speaking of Dr. Francis

Climate Change: Greenland Melting Tied to Shrinking Arctic Sea Ice

“Blocking-high” pressure systems spawn most of the warming that melts Greenland surface ice, study says

Vanishing Arctic sea ice. Dogged weather systems over Greenland. Far-flung surface ice melting on the massive island.

These dramatic trends and global sea-level rise are linked, according to a study coauthored by Jennifer Francis, a research professor in Rutgers University’s Department of Marine and Coastal Sciences.

Link

[D]

Fish here. I don't know how you have time for your day job, Neven. Outstanding compilation.

Unfortunately, the cracking event this year did not thicken the ice. The Icesat images have clearly shown that the ice thinned on the Pacific side. Thin ice is consistent with Mercator Ocean model data in the Beaufort which shows evidence of mixing of cold relatively fresh water of Pacific origin through the 300 meter Atlantic water layer. The Mercator model also shows the rest of the Atlantic water layer has warmed a bit except for the an area near the Atlantic water inflow where a broader inflow area than last year's has a lower peak temperature.

In short, the NAO and AO are producing the expected results. The ice thickened in spring 2013 when there was a large high pressure area over the *whole* Arctic ocean. This year there is a dipole. The dipole promotes ice export and Atlantic water inflow.

[Colorado Bob]

North Atlantic freshening from land ice melt, cold blob, stronger storms
Jason Box

Link

[Neven]

I don't know how you have time for your day job, Neven. Outstanding compilation.

Thanks, Fish, it's my night job. ;-)

I wanted to post this a month ago, and do a part 2 at some point, but this works too.

Unfortunately, the cracking event this year did not thicken the ice. The Icesat images have clearly shown that the ice thinned on the Pacific side.

I'm afraid you may be right.

[Neven]

The NSIDC calls the maximum.

[navegante]

The Cryosat map does NOT show thickened ice well above 2m along the coast nor does PIOMAS February animation shown over the Forum. However the Feb average PIOMAS map does. Glitch of PIOMAS gridded data?

[navegante]

Along the coast of ESS I wanted to say.

[AbbottisGone]

Qu: Sea ice is frozen ocean water. It forms, grows, and melts in the ocean. In contrast, icebergs, glaciers, and ice shelves float in the ocean but originate on land. For most of the year, sea ice is typically covered with snow.
Quick Facts | Quick Facts on Arctic Sea Ice | National Snow and Ice ...
https://nsidc.org › cryosphere › seaice

- This is a quote from nsidc. I was under the impression snow didn't fall at the poles.

This may be the wrong place to ask but then it may be just the correct one: "Are changes in snowfall occurring, specifically where it's occurring?"

[Rob Dekker]

Just to get a sense of how insanely warm the past two months were, here is an NCER/NCAR timeseries plot of the 1000 mb (surface) temperatures for Jan/Feb since the 1980's :

As Neven explained, the winter temperatures are not a good predictor for the minimum ice extent in the summer. Historically, the correlation between winter temps and summer melt extent is simply not good at all. Physical explanation may be that small temperature differences in winter do result in substantially thicker or thinner ice, and thus the 'noise' in winter temperatures gets overwhelmed by the variability of summer weather.

Yet, with such a HUGE temperature anomaly over the past winter, it is a really good test of how long this "non-correlation" holds. September will tell...

[Rob Dekker]

That should say "..that small temperature differences in winter do NOT result in substantially thicker or thinner ice".
And the Y-axis on the plot are in degrees C.

[jdallen_wa]

Rob Dekker - your comment highlights how we look at the surface of the changes taking place, and miss the fundamental one - the total heat content available to the system.

There always has been enough energy in the Arctic to keep it ice free; there has never been (at least in human reckoning) a mechanism which delivered that energy to the sea surface.

What is happening, has happened, is the total heat content is rising, and reached a point, where normal fluctuations in the distribution of heat in the Arctic season over season, now have a disproportionate effect on what it looks like.

To illustrate - a melt season like we had in 2012, if it happened in 1980, would have produced a minimum of about 5.5 million KM2. If that happened now, we would be flirting with an ice free arctic - under 2 million KM2; and this doesn't even account for the qualitative difference in the strength of the ice.

More than at any time in the last several million years, the summer ice minimum is now at the whim of variations in our weather - which has become progressively more volatile and energetic.

It might not be 2016. It might not be 2017; but it will be sooner than later that the pendulum swings, and we have a more rather than less active melt season that delivers us under 1 million KM2 at minimum. I think my 2029 estimate is now too conservative.

[navegante]

Rob, this has been a sustained difference of several degrees, for months, as unprecedented as shown in your graphic. Effect on ice thickness in some regions should not be that negligible this time. But I'd agree this plays a lesser role in an early or delayed start of melting.
Jdallen, you miss that, part of that heat content you talk about is overall thinning of ice over the years.

[jdallen_wa]

I'll respectfully disagree, navegante. The actually "250 kilo gorilla" is heat at depth in the Arctic basin - mostly below 100 meters or so.

By comparison, the thinning of the ice, now at an average of 2 meters plus chage thick, while significant, I do not think represents as big a change in enthalpy as the increases in temperature at depth.

I think its the heat being retained year over year at depth that's going to be the key player... because it reduces the heat required to raise the temperature of the top 50M or so of ocean, and puts it all that much closer to the threshold required to cause heat to transfer into the ice, rather than ocean.

Since 1980 its estimated that the heat content of the oceans has increased by over 17 Petajoules. 17 x 10^22 joules. That's a pretty astonishingly large amount of heat, even when you consider how small of a fraction of it ends up north of the Arctic circle.

So, the thinning of ice is no doubt significant. I'm not sure its as great in importance as the heat that's flowing in underneath it.

[Benje]

That is a lot of heat Navigante. By my reckoning 17 Petajoules has the capacity to melt about 500 million cu km of ice: is that right? Maximum Artic sea ice is a "mere" 16,000km cubed and even Greenland has "only" 2.5 million cu km cubed of ice. Can you confirm. If so you are absolute right.

[navegante]

I am confused Benje. You may be addressing JD Allen.
If I could understand the mechanism for retaining that heat excess JD Allen, but I don't know about it.
My point is that even if small, the reduction of thickness and ice volume over the years represents heat excess trapped by the Arctic Ocean, in form of latent heat. I dont know what share in total energy increase.

[Yvan Dutil]

I would like to add some basic physics of phase change to the discussion.

Freezing is a non-linear process. However, in one dimension, it can be described by the Stephan's law.

This imply that the ice thickness would be proportionnal to the square root of the frezzing degree days.

This is probably why we have not seen any correlation between winter temperature and summer ice cover.

[Neven]

Over on the forum Wipneus announces a 125K drop for CT SIA, so it looks highly likely that the max has been reached there also.

[Neven]

Good article on The Guardian by Suzanne Goldenberg: Arctic sea ice extent breaks record low for winter

[AbbottisGone]

Yvan Dutil,

Does "Stephan's Law" tell us why sea ice can only get 3 metres thick?

[Yvan Dutil]

AbbottisGone, if FDD as a maximum ice thickness has also a maximum. Of course compaction can change the picture.

[Bill Fothergill]

@ Benje & jdallen
(& anybody else interested in Ocean Heat Content)

Much of the early work in establishing a value for the rise in OHC was done by Sydney Levitus of NOAA.
https://www.nodc.noaa.gov/outreach/news_sydney_levitus.html

The figure given above by jdallen of 17 x 10^22 joules can by found here...
https://www.nodc.noaa.gov/OC5/3M_HEAT_CONTENT/

On the interactive chart, Fig 1 gives the OHC values for 0-700 metres, but Fig 2 gives a value about 40% higher for 0-2000 metres.

Please note that 17 x 10^22 joules is actually the same as 170 Zetta joules, not 17 Peta joules. (A difference of 7 orders of magnitude.)

As regards how much ice that would melt, let's see if I can still remember how to do this stuff...

The latent heat of fusion of water is about 334kj/kg, therefore 17 x 10^22 joules would melt about 5.09 x 10^17 kilograms of ice. (With no temperature change.)

The density of sea ice can obviously vary considerably, but a value somewhere in the vicinity of 910 kg/cubic metre will not be too far off the mark. That means our mass of ice would occupy a volume of about 5.59 x 10^14 cubic metres, or about 559,000 cubic kilometres.

Can somebody please check the calculations? I am having increasing difficulty with my eyes (never mind the brain) and therefore could easily have cocked that up.

cheers btf

[Al Rodger]

Bill Fothergill,
170 Zj to melt 5.09 x 10^17Kg ice? I find the bottom paragraph on the PIOMAS page is a good memory jogger if I ever forget the ~3,000 Gt(ice)/Zj. (They actually say 16,400 cu km requires "about" 5 Zj.) Working that through, it works out on the nail at 5.1 x 10^17 kg ice. You have to say, it's a mighty fine web page, that PIOMAS one is!!

[AbbottisGone]

Sorry Yvan,
I will elaborate.

A little birdy once told me that sea ice can only achieve a thickness of 3 metres naturally i.e. with no compaction.

Does "Stephans Law" explain this as a true fact?

(... maybe I should google 'Stephans Law' ;>)

[Yvan Dutil]

@AbbottisGone This is likely.

Actually, arctic ice is the third historical problem studied:

http://sabotin.ung.si/~sarler/sarler_papers/1995_SARLER.pdf

[Werther]

To contribute to Neven’s wonderful compilation, I’ve calculated the mean temp anomaly for the period 1 October – 25 March based on this CAD drawing:

For the Arctic Ocean the calculation added up to a +4.2 dC anomaly.
That might not sound as spectacular compared to the data that have been circling around the Blog and Forum during the last few months.
But I did this FI at the end of ’13-’14, which produced IIRC a mean between +1 and +2 (which was pretty awesome in those days).

My friends, +4.2 over such a large area and during six months is terrifying…
I’ll put a larger version up on the Forum.

[Neven]

Very nice, Werther!

And I agree, 4.2 °C is huge.

[navegante]

Lowest area; close to smallest thickness; lower snow cover on land; low snow depth on ice; and, the hottest NH temps on record.
If anybody has watched LOTR this sounds like Gimli laughing before starting the desperate final battle.

Anyway, for the latest three reasons I doubt this will be a repeat of 2013 but who knows. Gimli and comrades won the battle against all hopes :-)

[navegante]

Damn sorry for the spoiler :-/

[AbbottisGone]

http://berkeleyearth.lbl.gov/locations/31.35S-114.97E

Is this a reliable site?

[AbbottisGone]

http://berkeleyearth.lbl.gov/auto/Regional/TAVG/Figures/canada-TAVG-Trend.png

[Bill Fothergill]

@ AiG

If you are unfamiliar with Berkeley Earth - formerly known as the Berkeley Earth Surface Temperature project (BEST) - you could have a quick dekko at the wiki entry.
https://en.wikipedia.org/wiki/Berkeley_Earth

Their Global (Land + Ocean) anomaly file is here...
http://berkeleyearth.lbl.gov/auto/Global/Land_and_Ocean_complete.txt

You can easily see for yourself how this stacks up against the HadCRUT, Gistemp and NOAA equivalents. I've been tracking BEST along with these three other surface datasets since it came on-line a few years back.

One of the people working on Berkeley Earth provides comments on this blog from time to time.

[Jim Hunt]

JAXA extent is back down to the lowest ever level for the date (since their records began). 13,560,921 km² on March 30th:

http://GreatWhiteCon.info/2016/03/nsidc-announce-the-2016-arctic-sea-ice-maximum-extent/#comment-214046

[John Christensen]

Thank you for a great Arctic winter analysis Neven!

The only item I was missing was a review of the atmospheric conditions, which certainly seem to have been a factor for the Arctic sea ice this winter:
- November and December were dominated by negative AO index, which brings more cloudiness and low pressures to the Arctic region, causing reduced ocean heat loss, higher temperatures, and moves the jet stream further north with many storms entering the Arctic seas.

(In contrast, Oct, Nov, and Dec 2012 all had negative AO index, which caused predominantly clear skies, more heat loss and increased sea ice build-up).

[AbbottisGone]

Um, John: were you trying to confuse me on what a negative AO index means... because you did !

[John Christensen]

Hi AIG,

No, I was not trying to confuse you, so please let me know what leads to that state of mind.

The AO index:
https://en.wikipedia.org/wiki/Arctic_oscillation

[John Christensen]

Darn, you were right, thanks AIG!

What it should have been:

- November and December were dominated by positive AO index, which brings more cloudiness and low pressures to the Arctic region, causing reduced ocean heat loss, higher temperatures, and moves the jet stream further north with many storms entering the Arctic seas.

[AbbottisGone]

...thanx john: because I actually didn't know either way and now I do so cheers!

[AbbottisGone]

- nsidc for march 30 looks like it's going to get real bad!

[Neven]

John, I had thought about doing a paragraph about the AO, but as this past season wasn't really all that spectacular AO-wise compared to the previous decade, I decided to just focus on the SLP distribution maps.

But here are small versions of the graphs I had made. The first shows the AO Index numbers from November to February (1-4) preceding the years I also used for the SLP distribution maps:

And here's a graph showing seasonal averages for the 2006-2016 period:

[John Christensen]

Hi Neven,

Thank you very much for sharing this.

I was trying to consolidate your numbers with the monthly values from my data from NOAA, which seem to be slightly different:

Winter Nov Dec Jan Feb
2006/07 0,521 2,282 2,034 -1,307
2007/08 -0,519 0,821 0,819 0,938
2008/09 0,092 0,648 0,8 -0,672
2009/10 0,459 -3,413 -2,587 -4,266
2010/11 -0,376 -2,631 -1,683 1,575
2011/12 1,459 2,221 -0,22 -0,036
2012/13 -0,111 -1,749 -0,61 -1,007
2013/14 2,029 1,475 -0,969 0,044
2014/15 -0,53 0,413 1,092 1,043
2015/16 1,95 1,444 -1,445 -0,023

What is noticeable from these numbers:
1) The winter of 2006/07 saw positive AO in Nov, Dec, and Jan, which seems to work a bit like melt ponds in the early spring: If the ocean does not loose heat in early winter months, ice extent tends to stay very low. And this winter had exceptionally low ice extent.
3) The 2009/10 winter had great (AO) conditions for ice growth after a slow start
4) The winter of 2011/12 also saw positive AO in early winter months, setting the stage for the summer of 2012.
5) The winter of 2012/13 on the contrary saw lots of clear skies and significant ice growth causing lots of 'recovery' discussion at the time.
6) The three latest winter seasons were not great from a weather perspective with positive AO in early months for two of them and just slightly negative AO for the start of the 2014/15 winter.

It is clear - and Wikipedia IMO has the best guide to the AO - that this is not the sole factor, but one of the components influencing the environment in which sea ice is created during the Arctic winter.

[John Christensen]

Neven,

Your first AO graph is actually great, as it shows the winters of 2006/07 and 2011/12 starting with very positive AO, and this past winter being as bad as those two for the first months of winter.

- Which certainly does not bode well for the coming melt season (If you like the ice to stay that is)

It seems to be less important how the AO is behaving in Jan and Feb compared to Nov and Dec.

If you had included the cold winter of 2012/13, it would have provided a nice contrast to those other years.

[Neven]

John, especially for you, here's the first graph including all years from the 2006-2016 period:

[wayne]

The biggest player shuffling the Arctic climate deck is ENSO.

At this time there is a full blown trend towards a La-Nina:

http://www.bom.gov.au/climate/enso/indices.shtml?bookmark=nino3.4

Truly at the wrong time of the year. The result is less clouds in the Arctic mostly covered by more snow. As expected, clear skies even in March favors sea ice accretion, but soon this will change, the biggest factor of this season is the greater snow cover in some large parts of the Arctic Ocean area. This slowed accretion a great deal during darkness, but also increases it in the spring when the higher sun would have done otherwise. I expect a sharp decline of sea ice extent when sun elevations are high enough to rip open the snow insulation. That is a coming crucial moment for this year. The steeper the trend decline in extent the greater the melt.

[AbbottisGone]

April might get nasty!!

[John Christensen]

A true work of art, thank you Neven!

Comparing to the longterm AO index for winter months (See below), it is clear that the four seasons with very positive AO (2006/07, 2011/12, 2013/14, and 2015/16) are outliers and that we have seen reduced sea ice area and extent increases during those winters.

Hi wayne,

It will be interesting, if we will indeed have a La Nina event this year, but I have not seen any papers linking La Nina to negative AO/clear Arctic skies, so please share if you have references or your own data to support that.

Looking at the longer-term AO trends for winter months, it seems like we have a multi-decadal trend, as seen from the averages of NOAA AO data:

Period Winter (Nov-Feb)

Average (1950-2015) -0,28

Average (1950-1959) -0,50
Average (1956-1965) -0,75
Average (1966-1975) -0,40
Average (1976-1985) -0,54
Average (1986-1995) 0,42
Average (1996-2005) -0,24
Average (2006-2015) -0,05

From the numbers above:
1) Long-term average AO (1950-2015) is negative for the winter season (Nov-Feb), indicating overall tendency for clear skies.
2) Negative AO was most pronounced in the period of 1950-85.
3) 1986-95 indicated a decadal-long shift to positive AO during the main winter months, which generally must have reduced ocean heat loss and therefore limited sea ice growth
4) 1996-2005 saw overall negative AO again, but since 2006 we have seen a jigsaw/non-decided trend for AO during winter months.

These longterm shifts are also visible from the NOAA graphic, although it is looking at Jan, Feb, March:
http://www.cpc.ncep.noaa.gov/products/precip/CWlink/daily_ao_index/JFM_season_ao_index.shtml

[wayne]

Hi John,

These are observations like your AO data (care to show papers on how AO going all the way to the Great Lakes can be taken seriously for the Arctic?), far better than papers, the data is in the sky. In March just past there was 3 weeks of solid clear skies, along with very few apparent tropopause cloud condensation nuclei. The last time trend toward La-Nina in spring was 2008 (and certainly 2012) with similar Arctic clear skies periods . THese can be also observed daily on HRPT satellite products.

And its simple to understand, EL-Nino peaks coincide with greater # of thunderstorms world wide. But in particular the Anvil CCN overshoots past the tropopause in the equatorial Pacific spread all over the world including the Arctic, hence fallout from El-Nino Cumulonimbus creations create more clouds. The opposite holds just as well, when La-Nina is trending, there is usually a remarkable more prominent absence of clouds in the Arctic.

[opensheart]

Now that we can see the whole winter in review. Does anyone think the storm at the very end of Dec 2015, that seemed to telliconnect the near peak of El Nino with the cold blob in the North Atlantic, and bring above freezing temps close to the North Pole was a Dragon King Event?

http://robertscribbler.com/2016/01/04/climate-change-and-el-nino-locked-in-tempestuous-embrace-teleconnection-between-hot-equatorial-pacific-and-north-atlantic-cool-pool/

[Neven]

John, one of the first blog posts I wrote involved Wayne's theory on the link between ENSO and Arctic cloudiness: Arctic sea ice melt: a correlation with ENSO?

[navegante]

A hell of a theory, Wayne. Allow me to ask, do you expect Big Blue this time?

[wayne]

Navegante

Yes, big blue , you remember it well, it was 2008, nothing exactly repeated that spring yet, but this season is very close. April will confirm so.

Every Arctic spring has its own style. This years signature is with greater snow cover (along with record warm temperatures and extensive cyclonic penetrations). Warmer temperatures and more open water is what to expect during a very strong winter El-Nino. 2016 Arctic spring skies turned blue very quickly. In part by the North Pacific and Atlantic sst's cooled by greater multi cyclonic cloud coverage lasting months, and the sudden further warming from the sun of an already warmer Arctic atmosphere.

2016 much thicker snow cover is also very interesting, it slowed ice accretion but delays direct exposure of sun rays to sea ice. Sublimation will eventually, open up the snow like stretched open cloth fibers, this will start happening in about 3 weeks. I would expect a very accelerated melt because the sea water under the ice was spared a greater loss of energy. Especially if 2016 big blue continues, and by all imagery available there is no expansion of cloud cover in any Arctic quadrant as usually should be in April. That was 2008's main feature, 4 weeks cloud free following a March likewise, the relentless sunshine gave very early melt ponds.

[John Christensen]

Thank you for the link Neven!

wayne,

I will certainly check out your theory and also it's very enlightening to see more about your background.

The NOAA AO index is still positive, but is clearly trending towards moderate negative, so will be very interesting to follow the development.

[navegante]

Thanks Wayne. Only one comment. Last time I checked over the forum, the kind of consensus there was that the snow depth over most of the Arctic ice was relatively small after this Winter. Is there a source of information that indicates otherwise?

[wayne]

Navegante,

This may be a matter of graphs which cover the entire Cryosphere, there has been a great amount of snowfall early this past winter between October and November.

John,

Background is the right term, my background is literally the Arctic right outside, which more than 30 years of meteorological observations in the Arctic, nice experience for a meteorological observer.

There is no solid well versed science without myriad observations, there is no scientific theories that I know of which don't require a confirmation of sorts. My biggest discoveries or theories came about by extensive data collection first, the opposite process of most scholars, the experience eventually percolates to a realization . Instead of theorizing from well accepted physical models (which are artificial constructs, especially like the AO) , I transcend ideas from living through the real model in situ.

Papers are nice though, for instance Toxophene fallout from Southeast Asia is common here (from science papers). Therefore cloud seeds from overshooting tropical CB's is the next logical step to conclude that there is a Tropic to Arctic fallout process.

I prefer my peer being the future , because there is no tougher reviewer or peer than the observations yet to be written from a reliable source, writing papers is good but time consuming, is a gig for others to do, and sometimes I join them. But I much prefer writing discoveries directly (my web pages) to anyone who has an interest in Atmospheric science or really deep cutting edge optical physics.