The 2016/2017 freezing season

[werther]

I'm following all available media though I do not produce enough work to post frequently.

JDAllen, as I still stick to my dire 'black swan' prediction for '17, I see differences on the way toward that event.
'16-'17 is not like last winter. It follows a different path. First three months were INCREDIBLE compared to any year. January not so. It will be revealing to see how the present Sudden Stratospheric Warming will pan out through February.
Odds are still in line and ice accretion is bad over the whole season up to now. But Feb-April will be decisive on how severe this is going to be.

[jai mitchell]

The high air temperatures by themselves will be unable to cause anything beyond trivial surface melt, perhaps a few MM at best.  The air masses simply don't carry enough heat with them.

JD,

with all due respect, this is not what the science has shown.

for instance, this excellent presentation of the December 2015 warming event.


also see:  (note many links and supplemental documentation on this!
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5209705/

Numerical experiments indicate that the warming effect of sea ice loss and associated upward turbulent heat fluxes are relatively minor in this event. This result suggests the importance of the synoptically driven warm and moist air intrusion into the Arctic as a primary contributing factor of this extreme Arctic warming event.

and

with regard to the impacts of the warming event, the best paper is found here:

http://journals.ametsoc.org/doi/pdf/10.1175/JCLI-D-15-0773.1

The Role of Moist Intrusions in Winter Arctic Warming and Sea Ice Decline
CIAN WOODS AND RODRIGO CABALLERO

An increase in the frequency of intrusions
can therefore drive bottom-amplified warming
trend even in the absence of sea ice loss. In addition, the
intrusions themselves drive sea ice retreat in the marginal
zone and thus promote the upward turbulent fluxes that
help produce bottom-amplified warming.

[Archimid]

I wonder if the hot air intrusions will continue during the melt season.

[magnamentis]

The high air temperatures by themselves will be unable to cause anything beyond trivial surface melt, perhaps a few MM at best.  The air masses simply don't carry enough heat with them.

JD,

with all due respect, this is not what the science has shown.

for instance, this excellent presentation of the December 2015 warming event.


also see:  (note many links and supplemental documentation on this!
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5209705/

Numerical experiments indicate that the warming effect of sea ice loss and associated upward turbulent heat fluxes are relatively minor in this event. This result suggests the importance of the synoptically driven warm and moist air intrusion into the Arctic as a primary contributing factor of this extreme Arctic warming event.

and

with regard to the impacts of the warming event, the best paper is found here:

http://journals.ametsoc.org/doi/pdf/10.1175/JCLI-D-15-0773.1

The Role of Moist Intrusions in Winter Arctic Warming and Sea Ice Decline
CIAN WOODS AND RODRIGO CABALLERO

An increase in the frequency of intrusions
can therefore drive bottom-amplified warming
trend even in the absence of sea ice loss. In addition, the
intrusions themselves drive sea ice retreat in the marginal
zone and thus promote the upward turbulent fluxes that
help produce bottom-amplified warming.

JM, what comet to my mind first is that he explicitly mentioned "without heavy winds = storm" while your
links link to events that explicitly were related to warming jointly with storms and again he said that if that warmth will not happen together with strong winds that the impact will be minor. so you're both right, it just exists the possibility that the "without storm" thingy evaded you. if not, i'm sorry, i just got the impression that like so often we mean the same but fall for small but significant misunderstandings at times.

nice weekend @all

[JayW]

80 hours. 1/30-2/3

Imagery courtesy of university of Alaska at Fairbanks.

Tough to see a lot, but it does appear that there's a general left to right movement of most ice in this view.

Alaska at the bottom.

http://feeder.gina.alaska.edu/snpp-gina-alaska-i05-images?search%5Bfeeds%5D%5B14%5D=1&search%5Bsensors%5D%5B3%5D=1

[seaicesailor]

Yep, the 12Z GEFS, GFS, and EC are consistently going nuclear in 5-7 days.

Related with that warming event in about 5 days and beyond, look at the Scandinavian high at 1050+ hPa. Gee is that usual? (ECMWF last forecast for Feb 9th 12Z).
All the coldness being displaced to North America and Central Europe as well.

[Tigertown]

The way the Lows are set up over the next few days, they look like gears in a piece of machinery or pump, which exchanges surface air between the Arctic and mid-lats.
Starting today thru the 8th

[jai mitchell]

long range forecasts are for a near record low in the atlantic next week (938 mb) , have not seen its arctic impact potential/as of late low pressures are spiraling into Greenland for some reason. . . never seen that before, it is like the steering currents of the upper atmosphere have faltered and the lower tropospheric heat/water vapor are supercharghing these storms.

see images here:  https://twitter.com/RyanMaue/status/827595074460610562

[Tor Bejnar]

I have processed historical FDDs at 3 degree increments, both lat. and long. over one quadrant of the Arctic.  The difficulty is in presentation for me.  Perhaps this will elicit some suggestions.   ...

A graph used to show long-term drought shows a vertical axis of accumulated rainfall deficiency (anomaly) (mm) of rain and a horizontal axis of current month and previous months (going back even 5 or 15 years).  Different lines start at different ending dates (such as ending 1/2017, 1/2013 and 1/2008 because those were drought periods).  [example: 1/2017 - 20mm deficit; 12/2016 - 10mm deficit, so marked at 30mm; 11/2016 - 30mm deficit, so marked at 60mm; 10/2016 - 20mm surplus, so marked at 40mm.] (Internet search: examples of similar graphs are on page 14 of this USGS publication (PDF), only these start at a date and move forward in time, and compare different locations.)  One can then compare 'this' drought with past droughts intensity and longevity.  If you go back far enough in time (50 years, say), all lines should end with virtually no deficit, unless there is a long-term drift in rainfall.

I imagine seeing a graph showing N80 FDD anomalies in a similar fashion.  It will probably show how intense the heat has been these past 13 or 14 months.  It will also probably show that recent years have more FDD deficiencies than earlier years, showing a long-term drift in Arctic temperatures.

[Tigertown]

It is getting late into the evening where I am, and I just looked at the most recent images available.
I had looked at everything this morning, and from what I remember, I can honestly say that most of the ice looks worse now than this morning. I wish that I would have dl'd the ones this morning; may have to make that the new morning routine. That's getting pretty bad, when you need to compare images from the same day.



P.S.  I did get a good clear picture of the Bering Strait this evening.

[Blizzard92]

Hi everyone, lots of discussion about FDD recently - I am in the process of making some charts. Here's the current 80°N+ anomaly... (color scheme --> blue (old) to yellow (recent))

You will be able to find them here: http://sites.uci.edu/zlabe/arctic-temperatures/

[CognitiveBias]

Blizard92, I think your chart looks great.  And the others on your site as well.

We are becoming very familiar with the dramatic 2016/17 FDD deficit.

What would be even more interesting, imho, is a 4D representation showing the temporal and spatial distribution of the changes.  As Neven pointed out, similar work has been done over at the Albedo-Warming Potential thread.

https://forum.arctic-sea-ice.net/index.php/topic,1749.0.html

[ktonine]

Hi everyone, lots of discussion about FDD recently - I am in the process of making some charts. Here's the current 80°N+ anomaly... (color scheme --> blue (old) to yellow (recent))

Zach, when I first started posting FDD graphs last fall one of the suggestions was to spell out "Freezing Degree Days" at least once on the graph -- many people simply don't know what FDD stands for.  This is especially true when the graph gets reposted on Twitter, Facebook or other general public sites with an audience that is not steeped in weather or climate terminology and its acronyms.

Otherwise it looks great - well, visually, the data not so much

[Blizzard92]

Thanks! Yeah, I tried to spell it out along the y-axis.

btw PIOMAS numbers are in... ugly! (from http://sites.uci.edu/zlabe/arctic-sea-ice-volumethickness/)

[Tigertown]

I am surprised it came out that high, really. Better than the 14k km³ on the JAXA volume chart by Wipneus. Both are about as far behind their own numbers for 2016, though.

For PIOMAS, that's about 1500 km³ behind last year at this time, and better than 4000 km³ lower than 2014 and 2015 going into February.

[romett1]

Tigertown - I would say it's about 2,300 km³ less than last year (red line was 2016). And first half of February is not sounding good at all.

[jai mitchell]

Thanks! Yeah, I tried to spell it out along the y-axis.

well I guess that shows that suppression of ice growth does lend itself to increased rates of growth during cold(er) variations.   Just eyeballing it it seems to be a little less than 14.5 

in other words this Dec avg to Jan avg growth was right in line with most previous year's accumulation, as strange as that sounds given the DMI temperature chart.

we shall see, the daily values are really not as important as the monthly averages.

[Tigertown]

Tigertown - I would say it's about 2,300 km³ less than last year (red line was 2016). And first half of February is not sounding good at all.

You are right as it was 18.5k+ at same time last year. I just made a faux pas.

[jdallen]

The high air temperatures by themselves will be unable to cause anything beyond trivial surface melt, perhaps a few MM at best.  The air masses simply don't carry enough heat with them.

JD,

with all due respect, this is not what the science has shown.

for instance, this excellent presentation of the December 2015 warming event.


also see:  (note many links and supplemental documentation on this!
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5209705/

Numerical experiments indicate that the warming effect of sea ice loss and associated upward turbulent heat fluxes are relatively minor in this event. This result suggests the importance of the synoptically driven warm and moist air intrusion into the Arctic as a primary contributing factor of this extreme Arctic warming event.

and

with regard to the impacts of the warming event, the best paper is found here:

http://journals.ametsoc.org/doi/pdf/10.1175/JCLI-D-15-0773.1

The Role of Moist Intrusions in Winter Arctic Warming and Sea Ice Decline
CIAN WOODS AND RODRIGO CABALLERO

An increase in the frequency of intrusions
can therefore drive bottom-amplified warming
trend even in the absence of sea ice loss. In addition, the
intrusions themselves drive sea ice retreat in the marginal
zone and thus promote the upward turbulent fluxes that
help produce bottom-amplified warming.

Hmmm. going to shoot from the hip before I look at the articles, but here goes;

My judgement is based solely on the raw energy available in the air, compared to the heat of fusion/melting required to melt ice.

Fundamentally, the energy required to melt one gram of ice would raise the temperature of a similar mass of air 80C.  If the ice is melting, the energy is *not* coming from the atmosphere, it's coming out of the ocean.

Edit:  to be clear - go back to my comment; I wasn't saying the ice couldn't melt.  I said the "high" atmospheric temperatures were not going cause melt.

If we have tubulence and turnover in the ocean, the heat will absolutely attack the ice.  However, that energy categorically is *not* coming out of the atmosphere.  What high temperatures do at this point in the year is not put energy into the ice; what they do is prevent energy from leaving the ocean.

[Csnavywx]

Note that the 2012 melt volume was around 19K m3. So -- in ballpark figures, if we only crest at 19K or just above, that sets up the possibility that we go near ice-free this year. It would require a whopper of a summer (2007 or 2012 level), but the chance is there. A persistence of the current anomaly would get us around 20K. Kind of gives an idea of how little margin there is left.

[jdallen]

Note that the 2012 melt volume was around 19K m3. So -- in ballpark figures, if we only crest at 19K or just above, that sets up the possibility that we go near ice-free this year. It would require a whopper of a summer (2007 or 2012 level), but the chance is there. A persistence of the current anomaly would get us around 20K. Kind of gives an idea of how little margin there is left.

I'm not convinced we'll melt out... yet.

I'm in pretty close agreement with you though.

There's some potential bad synergy here - as the ice is thinner, it will facilitate localized melt out which in turn will reduce albedo and increase insolation uptake.  Considering that, I don't think we'll need a bad a year as 2007 or 2012 to go very low.

At this point, I"m fully expecting SIE and SIA to drop under 2 million KM2.  Again, unlike previous years, my concern isn't that we'll have weather that will kill the ice; it's that we won't get weather that will save it.

[budmantis]

Given the current state of the ice, reaching a new record minimum in September will not require optimal melting conditions. In fact, if melting conditions are similar to 2007, the minimum will be much lower.

[Tigertown]

This weather pattern is really rockin' Nares Strait, with 63 km/hr wind and 3.29 m waves. I don't know if you can call it a polynia where it is, but whatever the clearing is called is getting bigger. The ice in Baffin Bay is losing concentration and loosening up. If this continues, don't be surprised to see Baffin get flushed entirely, as the wind in the near future favors it.

 P.S.    By the time I was through typing, the wind had increased to 75 km/hr and the waves to 3.46 m....

[Csnavywx]

Hi everyone, lots of discussion about FDD recently - I am in the process of making some charts. Here's the current 80°N+ anomaly... (color scheme --> blue (old) to yellow (recent))

You will be able to find them here: http://sites.uci.edu/zlabe/arctic-temperatures/

Thanks for this (and the PIOMAS update). Really eye-popping when compared to other years. I'm sure there's going to be a flurry of research on this winter soon. It's obviously way too early to say anything beyond speculation, but I hope this winter doesn't represent the sudden emergence of a persistent atmospheric feedback mechanism. If it is, it has the potential to overwhelm the biggest buffer the Arctic has left -- first year ice growth.

[Tigertown]

First frame is from Jan. 24th and the 2nd and third frames are today. I blame most of this on the Pacific storms, though maybe not all.
Last image is a gif. Click the image and click again to enlarge.

[Jim Hunt]

I'm sure there's going to be a flurry of research on this winter soon.

I've already started a research project on the topic. As much psychology and politics as physics. The overview is on ResearchGate:

https://www.researchgate.net/project/Alternative-Facts-in-the-Arctic

The latest news:

http://GreatWhiteCon.info/2017/02/alternative-facts-about-the-arctic-in-2017/

[seaicesailor]

It's interesting to verify that these days MYI is being dumped through Fram Strait, but also melting out before it reaches Svalbard, just as it happened in summer. Now the winds are going to change again, so not much ice will probably reach the islands.
Used the Terra brightness temperature worldview, the animations start on January 25 and finish on February 1. it is always amusing to see how many floes of nearly the size of Big Block melt out in the Arctic Ocean on January.
Some remnants are still present in the last picture, couldnt track anymore since the last days the area has been blocked by clouds.

[jai mitchell]

At this point, I"m fully expecting SIE and SIA to drop under 2 million KM2.  Again, unlike previous years, my concern isn't that we'll have weather that will kill the ice; it's that we won't get weather that will save it.

well said, the summer may indeed be very cloudy, also the increase in volume growth this January, in line with previous January volume increases, indicates that we may see an extension of volume growth in march and April that may help to reduce the volume anomaly somewhat.

[oren]

It's interesting to verify that these days MYI is being dumped through Fram Strait, but also melting out before it reaches Svalbard, just as it happened in summer. Now the winds are going to change again, so not much ice will probably reach the islands.
Used the Terra brightness temperature worldview, the animations start on January 25 and finish on February 1. it is always amusing to see how many floes of nearly the size of Big Block melt out in the Arctic Ocean on January.
Some remnants are still present in the last picture, couldnt track anymore since the last days the area has been blocked by clouds.

Thanks for the animation SIS. Very enlightening (and disturbing).

[jai mitchell]

The high air temperatures by themselves will be unable to cause anything beyond trivial surface melt, perhaps a few MM at best.  The air masses simply don't carry enough heat with them.

JD,

with all due respect, this is not what the science has shown.

Hmmm. going to shoot from the hip before I look at the articles,

well that's just dumb  Melt during a warm storm event has been documented in these and other locations.  please review before you make your assertions.

but here goes;

My judgement is based solely on the raw energy available in the air, compared to the heat of fusion/melting required to melt ice.

I understand that, and this is not a correct statement, heat fluxes into the arctic by the atmosphere during the winter are at least 5 (and this year probably 10) times MORE heat energy than ocean-borne heat. The question is not whether the atm is driving melt (during these events) it is how much.

Fundamentally, the energy required to melt one gram of ice would raise the temperature of a similar mass of air 80C.  If the ice is melting, the energy is *not* coming from the atmosphere, it's coming out of the ocean.

What about water vapor?  you are using dry-air specific heat, these storms raise precipitable water vapor from 1kg/m^2 to up to 12kg/m^2, This extra warm air/water mass is blowing in at 45 km/hr and eventually covers an area of over 3 million square kilometers.  There is more than enough heat intrusion to produce sporadic surface melt.  The nasa video shows this and you should also consider that first-year higher salinity ice melts with less heat in your estimation.

Edit:  to be clear - go back to my comment; I wasn't saying the ice couldn't melt.  I said the "high" atmospheric temperatures were not going cause melt.

Again, and please consider watching this short NASA presentation:  this is well documented.  ]

If we have tubulence and turnover in the ocean, the heat will absolutely attack the ice.  However, that energy categorically is *not* coming out of the atmosphere.  What high temperatures do at this point in the year is not put energy into the ice; what they do is prevent energy from leaving the ocean.

this is an interesting statement I prefer to look at sea ice surface energy balances, not ocean exchange.

probably a good idea to review again:  http://www.colorado.edu/geography/class_homepages/geog_4271_f10/lectures/week_2.pdf  This shows that heat from the atmosphere is the dominant force under NORMAL conditions.

note: once again, this is specifically referenced in the science:  https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5209705/

Numerical experiments indicate that the warming effect of sea ice loss and associated upward turbulent heat fluxes are relatively minor in this event. This result suggests the importance of the synoptically driven warm and moist air intrusion into the Arctic as a primary contributing factor of this extreme Arctic warming event

[ktonine]

this is an interesting statement I prefer to look at sea ice surface energy balances, not ocean exchange.

probably a good idea to review again:  http://www.colorado.edu/geography/class_homepages/geog_4271_f10/lectures/week_2.pdf  This shows that heat from the atmosphere is the dominant force under NORMAL conditions.

note: once again, this is specifically referenced in the science:  https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5209705/

Numerical experiments indicate that the warming effect of sea ice loss and associated upward turbulent heat fluxes are relatively minor in this event. This result suggests the importance of the synoptically driven warm and moist air intrusion into the Arctic as a primary contributing factor of this extreme Arctic warming event

jai - what you've bolded is an answer to the question (in the specific instance in question): Was the atmospheric system caused by sea ice loss or did sea ice loss cause the atmospheric system?  It says nothing about warm air melting (or not melting) ice.

This question is one of the hotly debated topics among arctic climate scientists.  As Jim Hunt reminded us just the other day:

James Screen is live tweeting from the "Arctic Change and Its Influence on Mid-Latitude Climate and Weather" workshop in Washington DC. This one particularly caught my eye:

[Judah Cohen] challenges Jim Overland's assertion that Arctic reinforces but cannot drive circulation change. Plenty to discuss later.

Warm air will melt ice, but water and insolation play a far greater role.  What few people realize is that over the same period we've seen decreasing extent and volume, the two warmest months of the year (June and July) show a decreasing trend in N80 temperatures.  Yes, June and July are cooler now than they were in the 60s, 70s, 80s, and 90s. 



I have postulated previously that the reason for this change is an increase in open water during the melt season and that the newly opened sea water is *colder* than the ice and melt ponds it has replaced.  And since the air will assume the temperature of the ice or water beneath it, a decrease in sea ice can actually lead to cooler air temperatures.

[DrTskoul]

mC_PΔT + ΔH_vapor-water.
Yes but..

Forgot sth. Ice is immobile compared to atmospheric masses flowing for days with the same temperature.

[Tor Bejnar]

...
well I guess that shows that suppression of ice growth does lend itself to increased rates of growth during cold(er) variations.   Just eyeballing it it seems to be a little less than 14.5 

in other words this Dec avg to Jan avg growth was right in line with most previous year's accumulation, as strange as that sounds given the DMI temperature chart. ...

I think this is what you're saying:  thinner ice requires less 'cold' to thicken than does thicker ice.  Therefore, given the ice is thinner than normal at this time of year, Arctic ice requires fewer FDD to grow the same volume than it used to.

[jai mitchell]

Yes,

I understand the topic is under debate.  The reference indicates that the warmth of the event (and the associated observed melt) is due to intrusion and not dominated by heat flux from the oceans. 

The question of changes in mid-latitude moisture/heat intrusion being caused by lower regional sea ice or caused by changes in tropical/mid-latitude circulation patterns is not answered.  however, the fact is that the events began as a result of the 2015/2016 El Nino, were focused on the Kara in December of 2015 and the sea ice extent in that region at that time was not significantly below previous anomaly years (2011 and 2009).  So while there is a likely feedback from lower sea ice levels, the increased water vapor circulation from the El Nino is the dominant factor.  In addition, the continuation of this event after the El Nino shows that another additional feedback is driving current system intrusions.  I posit that the 10% reduction (more now) in Chinese SO2 aerosols is changing atmospheric circulation patters in the mid latitudes in ways not currently described in the models.  There is also, likely, a sea ice extent feedback factor as described in the Warm Arctic Cold Continent studies:  https://scholar.google.com/scholar?q=warm+arctic+cold+continents&hl=en&as_sdt=0&as_vis=1&oi=scholart&sa=X&ved=0ahUKEwjg4d7wiPfRAhWphFQKHTWSAP4QgQMIGjAA

Tor,

yep, and the indication is that if the piomas anomaly is continued (It will) into the latter half of the freeze season we will likely see some growth above previous 'normal years' at that time, though (I feel) not enough to overcome the anomaly.

[FishOutofWater]

Cause and effect reasoning isn't particularly perceptive when dealing with non-linear coupled processes. The warm Atlantic water in the Barents sea and north of Svalbard amplifies atmospheric blocking over northern Europe. There may also be an atmospheric teleconnection to the Pacific because the flow of Siberian air into the western Pacific is enhanced by the blocking over northern Europe. Thus troughs are deepened off the coast of Asia and mid Pacific ridging may be enhanced.

We have seen very strong planetary wave number 2 activity since November.

Moreover, we seeing slower thickening of Arctic ice this winter in part because clouds and water vapor are reducing outward longwave radiation over the Arctic ocean. In winter, it isn't an issue of warm air melting sea ice. It's an issue of clouds and water vapor slowing the increase of thickness of ice across the Arctic.

[jdallen]

Again, and please consider watching this short NASA presentation:  this is well documented.  ]

No audio?  While I generally understand what the video is presenting, (temperature changes, atmospheric flow, changes in ice coverage), its not explaining where the energy is coming from. I'm also currently digesting the paper, which may give me some more insight regarding the questions I list below.

So here's the challenge I'm having with your argument; I'm still not seeing where the atmosphere has enough energy to produce the melt.

So some summarizing questions:

How much latent heat was carried into the region (net enthalpy and implied by carried water vapor)?

How much of that radiated out of the atmosphere?

How much heat which would *normally* be re-radiated went into the ice instead?

What was the volume of ice melted and how much energy would it require for melt?

[jai mitchell]

here is the same video with narration by Julienne Stroeve



source: https://www.nasa.gov/feature/goddard/2016/extremely-warm-2015-16-winter-cyclone-weakened-arctic-sea-ice-pack

[Tor Bejnar]

Note that the 2012 melt volume was around 19K m3. So -- in ballpark figures, if we only crest at 19K or just above, that sets up the possibility that we go near ice-free this year. It would require a whopper of a summer (2007 or 2012 level), but the chance is there. A persistence of the current anomaly would get us around 20K. Kind of gives an idea of how little margin there is left.

I'm not convinced we'll melt out... yet.

I'm in pretty close agreement with you though.

There's some potential bad synergy here - as the ice is thinner, it will facilitate localized melt out which in turn will reduce albedo and increase insolation uptake.  Considering that, I don't think we'll need a bad a year as 2007 or 2012 to go very low.

At this point, I"m fully expecting SIE and SIA to drop under 2 million KM2.  Again, unlike previous years, my concern isn't that we'll have weather that will kill the ice; it's that we won't get weather that will save it.

I'm bullish that some Arctic sea ice will survive the Northern Hemisphere (NH) summer of 2017.  (Or is it: I'm bearish that Arctic sea ice will melt out this summer?)  Here’s why:  in past years, like 2007 and 2012, there was more sea ice (volume) outside the Central Arctic Basin (CAB) than there is today.  These ‘southern’ areas have a longer melt season than does the CAB, so with the aid of global warming, tend to melt out.  This year, with less volume than usual (ever?) these peripheral areas may very well completely melt out, and may do so unprecedentedly early.  But because of the shorter melt season in the CAB (except for the Atlantic side of it), even with less ice than usual (ever?), CAB sea ice will likely hold on for another year or so.  The game-changer in my mind is if winds continually blow the CAB ice toward Svalbard/Fram Strait.

If the peripheral areas do melt out early, they will accumulate more surface heat than ever, and ‘we won’t be in Kansas anymore’, nor, perhaps, even in Oz (not the Australian one, but the make-believe one).

[jdallen]

here is the same video with narration by Julienne Stroeve



source: https://www.nasa.gov/feature/goddard/2016/extremely-warm-2015-16-winter-cyclone-weakened-arctic-sea-ice-pack

The narration still doesn't provide either an indication of where the energy came from, or measurements which imply the transfer of heat melting the ice actually came from the imported heat.

I'm reading further looking for such.  Haven't seen it so far. Still sounds hypothetical.

[jai mitchell]

here is the same video with narration by Julienne Stroeve



source: https://www.nasa.gov/feature/goddard/2016/extremely-warm-2015-16-winter-cyclone-weakened-arctic-sea-ice-pack

The narration still doesn't provide either an indication of where the energy came from, or measurements which imply the transfer of heat melting the ice actually came from the imported heat.

I'm reading further looking for such.  Haven't seen it so far. Still sounds hypothetical.

She says specifically at time :30 "transporting unseasonable heat and moisture into the Arctic from lower latitudes".

not sure if this answers your question but it might help https://usclivar.org/sites/default/files/meetings/2017/arctic-posters/Feldstein-Steven-2017-Arctic.pdf  see the right portion of figure 2 (top middle image)

-----------

edit: you may find this interesting:  http://www.meteo.psu.edu/~sxl31/papers/Baggett_Lee_Feldstein_2016.pdf

An Investigation of the Presence of Atmospheric Rivers over the North Pacific
during Planetary-Scale Wave Life Cycles and Their Role in Arctic Warming

[jdallen]

here is the same video with narration by Julienne Stroeve



source: https://www.nasa.gov/feature/goddard/2016/extremely-warm-2015-16-winter-cyclone-weakened-arctic-sea-ice-pack

The narration still doesn't provide either an indication of where the energy came from, or measurements which imply the transfer of heat melting the ice actually came from the imported heat.

I'm reading further looking for such.  Haven't seen it so far. Still sounds hypothetical.

She says specifically at time :30 "transporting unseasonable heat and moisture into the Arctic from lower latitudes".

Yes, I heard that as well.  However, it does not indicate whether that heat was sufficient to cause the melting, nor whether it was the source of the heat that was taken up to cause the melt.  Mostly what it implies to me is that it disrupted the radiative mechanisms that previously and normally were in play.

Also missing from the video are the immediate temperatures.  We had anomalies of up to 30C; however, across much of the region including the margins where melt was taking place, temperatures remained close to zero.  In some places, that anomaly brought temperatures barely *to* zero.  That's not a lot of gradient for heat transfer in the quantity required for melt to take place that quickly.

(cci daily reanalysis from 1 Jan 2016 included below as illustration of this previous point)

Let's talk about downwelling radiation as well.

Some of that will be native to the air masses entering the region, supported by energy released by moisture going through multiple phase changes as it eventually leaves in the form of precipitation as rain or snow.  No where do I see suggestions that this was sufficient in quantity to cause melt.

*Further* because of the green house effect added by that moisture, a significant component of that downwelling radiation comes not from that carried by the atmospheric inflow, but rather is radiation captured from the sea or ice surface by atmospheric moisture.  The question is still begged whether that would have been enough in both quantity and rate to cause the kind of melt we saw and are seeing.

So, my observations are obviously qualitative rather than quantitative.  I'll happily concede if actual measurement proves my analysis incorrect.

(Dang it, I forgot to include the scale in my snap shots.  For those not familiar with the web site, in the anom. image, the brighter the red, the greater the anom, with most of the central red region over the Barents running 20C+ above normal.  In the 2nd image, the blue/green interface represents the zero C line, with bluer to purple being coldest).

[Jim Hunt]

here is the same video with narration by Julienne Stroeve

Actually that's the voice of Linette Boisvert. Source:

http://GreatWhiteCon.info/2016/11/nasa-researches-storm-frank-in-the-arctic/

[ktonine]

She says specifically at time :30 "transporting unseasonable heat and moisture into the Arctic from lower latitudes".

jai - You seem to be arguing that the air temperature is melting the ice whereas the paper is arguing that a cyclonic mass of warm moist air melted the ice. Their argument is not your argument.  Figure 4 shows the net SEB plus  Downwelling Longwave Radiation, Sensible Heat, and the Latent Heat components of the equation.  And the effects of air temperature are not disambiguated from the effects of humidity, nor cloudy skies vs clear skies.  It's also worth noting that temperatures increased 3σ above the 2003-14 mean while humidity increased 4σ above the 2003-14 mean during the storm.

[jdallen]

Relevant to the current discussion of how much heat the atmosphere may be providing to current melt happening during storms.

1/1/2016 precipitable water in KG/M2.  This is relevant as it represents even more than temperature, the absolute quantity of heat available for release.  10KG of H2O represents enough water to form a plane 1CM thick on a square meter of some surface.

That means, the theoretical maximum heat available when an influx of moisture typical to what we see currently takes place (10-15KG/M3), that has a net enthalpy to force a phase change (twice - heat gets release when it precipitates as water, and again when that water freezes) of between 1-1.5CM of ice per M2.

So again, considering that won't all be translated into downwelling longwave radiation, but at the point of emission least half will end up heading out of the atmosphere, we are talking about perhaps 1CM of total melt potential. Add that, not all of that energy will be going into a phase change but rather will be dispersed into other heat sinks - like the ocean itself.  What's left over is very much in line with what I asserted - the energy available in the atmosphere would be sufficient only for very minimal - a few MM - surface melt of the ice affected.  The energy necessary to destroy anything much past nilas *must* be coming from somewhere else.

[jai mitchell]

the energy available in the atmosphere would be sufficient only for very minimal - a few MM - surface melt of the ice affected.

you are talking about a snapshot in time, these atmospheric river events are several days worth and transport water vapor on the order of 8X10^7 kg/s into the arctic.  Called Qr in the following paper http://www.meteo.psu.edu/~sxl31/papers/Baggett_Lee_Feldstein_2016.pdf

over a multi-day event this is quite significant.

note: also the spatial and temporal forcings are not distributed but rather impact local areas.

[ktonine]

The high air temperatures by themselves will be unable to cause anything beyond trivial surface melt, perhaps a few MM at best.  The air masses simply don't carry enough heat with them.

JD,

with all due respect, this is not what the science has shown.

jai - your argument has morphed from high temperatures alone to something else.

[oren]

Maybe the whole discussion should be moved to a science thread? I realize it touches on the current melting season, but the scope is wider, and it's becoming long.

Tor regarding you comment - there are several factors that could melt large parts of the CAB: Early melt-out of the MYI-less Beaufort, which is at a low latitude but within the basin with good access to the CAB. Highly mobile CAB ice as you mentioned - moving towards the warm water on several sides. Storms that could cause Ekman pumping using the heat at depth to melt the ice. And the potential loss of the thickest MYI ice to the Fram, as shown in the PIOMAS animations.
Not saying all these factors are sure to happen, or that the result is a given, but I think there's a substantial risk.

[Andreas T]

looking at the basics, unless the temperature goes above 0deg or -1.8 in the presence of saltwater, any amount of heat released won't cause melting full stop. Condensation could cause a lot of melting at 0deg, i.e. the air would not have to be warmer to cause more melting it could just bring more moisture (although the amount of moisture any m³ of air can carry is of course limited by its dewpoint.
What also needs to be taken into account is that the bulk of the ice is cold at the time of the year I believe is under discussion here (you are both talking about January 2016, JD and Jai?)
We have looked at buoy data in the buoy thread in that context.
When it comes to radiation, only something which is itself warmer that 0deg can bring the temperature of something else above 0deg. Unless there is another heat input with temperature above 0deg and we are talking about reduced heat loss (not happening in this situation).
When you are talking about radiation going up as well as down, JD, you must keep in mind that the opaqueness of the atmosphere and especially that of clouds must be taken into consideration, the tops of clouds radiating into space are colder than their bottom, radiating to the surface

I don't think there is an argument for actual significant melting taking place in January 2016. But of course reduced freezing at that time did result in increased melting later.
 What I would like to know, but must be hard to get data on, is whether there was increased precipitation (snow) which affected rate of cooling and melting in different ways later.

These buoys seem to offer same information on this but data are not that easy to access
https://www.awi.de/nc/en/about-us/service/press/press-release/schneebojen.html

[seaicesailor]

Well, the similar event at hand is starting in 48h and according to the 12Z gfs run it might be sustained and bring high temperatures for days (note the animation shows 2m air temperature, the 0C line well marked in red dividing green and blue).
Goes without saying, take this long forecast with grain of salt
Edit: the first frame is in 48h and the time step is 12 hours ... sorry for not caring much about the time, just wanted to show the evolution of the 0C line in the first 12 frames or so, or 6 days

[jdallen]

Maybe the whole discussion should be moved to a science thread? I realize it touches on the current melting season, but the scope is wider, and it's becoming long.

I can let it rest for the moment and leave Jai with the last word.

As seaicesailor suggested, we should watch the next coming storm with great interest.  Regardless of where the heat is coming from, it will be trouble.