Are we setting up for a Blue Ocean Event in Sept 2017?
Many climate scientists expect a gradual transition, with ice free not likely for at least a decade or more. Wadhams and a few others expect a phase change, with feedbacks leading to a rapid transition of the Arctic to open ocean much sooner.
Most climate scientists follow Chris Reynold's "Slow Transition" idea.
ktonine at the Arctic Sea Ice Forum offers this summary of it.
Critical to all this is that I am becoming convinced that the approximate levelling of PIOMAS volume over the last few winters is telling us that the pack is becoming dominated by FYI, whose thermodynamic equilibrium thickness is largely setting the peak volume in April. Even if one year, with exceptionally good melt weather, were to lead to extent below 1 million kmsq, this will be unlikely to be repeated, and for the record, I do not think this is likely anyway. To get to a state of near ice free conditions in late summer we will need to see significant thinning of the winter peak thickness, which needs far greater winter warming. I don't think this is likely to be a fast process.
So I do not expect to see a virtually sea ice free state until later in the next decade - at the earliest, I suspect that Overland and Wang may be proven right in pinning it on the 2030s. In terms of expectations amongst many in the amateur sea ice community this is a slow transition. However in geological terms it remains abrupt.
This year we *are* seeing significant thinning in winter thickness, but it still requires an even thinner pack to meet the requirements to get reliably under 1 million kmsq. So, the question still remains: is this winter's lack of FDDs a step change or is it an anomaly?
I've always been an advocate of slightly faster timing than Chris for these processes, but the arctic has always managed to surprise me with it's resilience. And in the end we're realistically talking about a difference of 10 to 15 years -- virtually no difference at all in scientific terms.
What I think we should also remember is that the scientist that first really went out publicly on a limb with an "over-the-top" prediction was Wieslav Maslowski. Back in 2006 Maslowski predicted a nearly ice free arctic in 2016 +/- 3 years. What many don't know is that Maslowski was not talking about sea ice are or extent - but volume. And 'nearly ice free' he defined as losing 80% of the 1979-2000 summer volume (see article by Joe Romm at ThinkProgress). 2012 came close. 2017 should come even closer - perhaps even make that prediction come true. [emphasis mine]
oren offers this caveat about Freezing Degree Days (FDD), which have been drastically lower this season.
Chris R's main assumption was that the freezing season remains mostly the same, with FDDs stable or perhaps undergoing a small decline, and that therefore arctic sea ice cannot just pass a tipping point and disappear following its first ice-free summer. Instead, even if a freak summer came along and melted all the ice, the refrozen arctic would still not necessarily melt out the year after. This is what he dubbed a "slow transition", as opposed to a one-way phase change.
The theory is very strong and Chris at the time gave many good arguments and explanations, but I believe this year has already shown its main flaw, and that is the FDD assumption. FDDs crashed this winter, leading to the possibility of a melt-out with a regular un-freakish summer. [emphasis mine]
So we have two schools of thought, and Freezing Degree Days is the pivot between them.
Amateurs such as Paul Beckwith expected melt-out last year. I can't imagine it will take longer than September 2017 or possibly 2019. Many new behaviors have emerged: jet stream changes, low Arctic pressure where there used to be high pressure, Atlantic storm tracks near or into the Arctic bringing both heat and moisture, stratosphere anomalies, shifts of the Hadley and Polar Cells, and the virtual disappearance of multiyear ice. The appearance of clouds in Spring and Summer the last couple of years helped the ice. This is also novel behavior. Overall I agree with the comparison to hysteresis, a nonlinear system fluctuating back and forth between two states, that often proceeds shifting from a previous stable state to a new one.
Hold on to your hats.
Suzanne at RobertScribbler's blog shares this:
And here is the latest PIOMAS from Neven: http://neven1.typepad.com/blog/2017/05/piomas-may-2017.html#more
His concluding remarks:
If this year’s melt is equal to the average of the last 10 years, there will be around 2500 km3 left in September (mind you, the 2012 record low minimum is 3673 km3). If there’s as much melt as in 2010 or 2012, this year’s minimum will barely go above 1000 km3. I don’t want to know what the Arctic looks like if that should happen.
There’s nothing else to do but hope that PIOMAS has it completely wrong, or else pray for lots of cold and cloudy weather in the Arctic this summer.
On another note, critiquing the idea that the Arctic will become a paradise after new shipping routes have opened up and the Ice receded, Leland Plamer sums up my reactions as well.
"Scott Borgerson ... envisions a not-too-distant future in which Anchorage and Reykjavik become as dynamic and nearly as important as Singapore and Dubai are today.”
He leaves out the part where the Arctic Ocean will likely become a hypoxic cesspool, covered by mats of green and purple photosynthetic bacteria, producing clouds of poisonous hydrogen sulfide gas, punctuated by methane geysers from dissociating methane hydrates. Onshore, exploding Yamal type craters and melting permafrost will possibly make permanent construction very hazardous, and clouds of hungry mosquitoes will likely prowl the land, carrying diseases now common in the tropics. Anthrax from the melting permafrost may compete with disease organisms we have never heard of from plagues of the past preserved by the permafrost.
A major portion of Arctic tundra became a CO2 emitter, much earlier than predicted. A feedback kicked in, releasing carbon "thousands and millions of years old".
The Alaskan tundra is warming so quickly it has become a net emitter of carbon dioxide ahead of schedule, a new study finds.
Since CO2 is the primary heat-trapping greenhouse gas — and since the permafrost contains twice as much carbon as the atmosphere does today — this means a vicious cycle has begun that will speed up global warming.
“Because it’s getting warmer, there’s more CO2 coming out which means it’s going to get warmer which means there’s more CO2 coming out,” explained Harvard researcher and lead author Roisin Commane. “And it will just run away with itself.”
The study is the first to report that a major portion of the Arctic is a net source of heat-trapping emissions. As a result, Commane warns that our current climate models need to be updated: “We’re seeing this much earlier than we thought we would see it.”
The Nares Strait, between the Canadian Arctic Archipelago and Northwest Greenland, has been open for a while. What looks like large pieces of thick multiyear ice float south and...
Tigertowne posted this gif, and "Where did it go? Charts show this ice that's now entering Nares to be old thick ice, but the way it crumbles makes for doubt. 5-21 vs. 5-22."
What looks like normal thick ice from satellite is likely honeycombed, smaller pieces refrozen together. This may be from the unusually low freezing degree days and/or the frequent storms.
Apocalypse4Real posted this observation from aerial survey.
Must interesting comments in the NSIDC field report:
NSIDC scientist Julienne Stroeve continued her Arctic field work into early April, moving from Cambridge Bay, Canada to Alert in Ellesmere Island. In Alert, Stroeve focused on sampling ice thickness and snow pack characteristics along a CryoSat-2 flight track within the Lincoln Sea. This is an area between northernmost Greenland and Ellesmere Island where thick, old ice remains. The scientists flew by Twin Otter each day, out onto the sea ice between latitudes 83°N and 87.1°N. The field campaign was also supported by an aircraft from the British Antarctic Survey carrying a Ka band radar, LiDAR, and a broadband radiometer. A NASA Operation IceBridge flight also flew over the same track.
The group noted that the ice was unusually broken up and reduced to rubble, with few large multi-year floes, forcing the pilots to land on refrozen leads that at times were only 70 centimeters (28 inches) thick. Pilots remarked that they had never seen the ice look like this.
A couple of comments from the Arctic Sea Ice Forum.
What I find most noteworthy is that most of the anomalously thick ice finds itself in an area where ice export is strong and there is little chance that any of this thick ice will survive the summer.
This shows Sea Ice thickness, with the white being thickest, as well as warmth in the ocean where it's liquid (the lower right beautiful fractal colorful section). Note that the peach colored thicker ice goes right up to the space between Greenland and Svalbard, where it's lined up to exit quickly and then melt. And note that the water just south of it is warm - green and even yellow instead of blue.
Now we need both below normal temps, clouds and minimal winds to avoid record losses of sea ice volume, area and extent.
So it looks as if we're likely to get record melt-out by September, unless the Arctic is cooler and cloudy and not stormy from now till then.
Neven Acropolis viewed the weather outlook with dismay: “I can’t imagine a worse forecast at this time of year. The past couple of melting seasons were marked by relatively weak preconditioning and thus a lack of melting momentum during July and August. Last year the Arctic clearly dodged a bullet because of it, but this year we may not be so lucky, given the record warm winter, record low sea ice volume and now open skies to cause plenty of melt ponding on that massive expanse of first-year ice.”
However, a promising new approach to sea ice prediction “calls for a minimum extent of around 4 million sq. km. which would be very low but still above the 2012 record of 3.62 million sq. km.”.
The weather to watch is high pressure on the Pacific side of the Arctic, which makes for sunny skies and melt ponding, accompanied by low pressure (stormy weather) on the Atlantic side, which pushes ice south to melt. They call this one-two punch a dipole pattern. The other big factor is Summer cyclones reaching the Arctic, because they smash ice and churn up deeper warm water to make ice melt on the bottom.
Everyone agrees that record low volume and fracturing means that bad weather will cause rapid melt. Will we only get a second lowest sea ice volume this year or a new low, is the question. Nobody really expects a Blue Ocean Event, though.
Predictions are all over the place at the Arctic Sea Ice Forum. As Rubickscube says, " ... short term variables seems to be favoring less melt, whereas long term variables seems to be favoring rapid melt." There's snow on the ice, less melt ponding, and snow in Siberia to cool that side. But volume is low.
A-Team reports that interpreting satellite and radar images is getting more complicated.
... ice is complicated enough already and processes that fool the radar could be more common as multi-year ice diminishes (or vanishes) as the Arctic amplification of warming precedes.
All the current segmentation schemes like extent, area, age, and volume will need to be seriously tweaked to keep up with once-rare ice formations and interactive atmospheric processes becoming dominant.
A segmentation scheme is an algorithm to interpret variations in data such as brightness, classifying particular areas as solid ice, fractured, slush, etc. When snow cover on ice thaws and refreezes in April, for example, it can create a layer of ice in the snow. Or frost flowers [image below] can pop up on top of either half-melted slush or on dark ice (which used to be rare). Such details can confound radar and visual data interpretation.
Thomas Barlow, at Arctic Sea Ice Forum, explains my own concerns:
At some point in the future, the Arctic Ocean will have a tipping point that is not seen in previous years (hopefully not this year, but it is a possibility).
I doubt it will be a slow year by year, decade by decade, slow incremental diminishment, until it is mostly blue, a long time from now.
The more open ocean (the Arctic Ocean), the more loss of albedo, the more warming waters, the more Atlantic intrusion, the more top to bottom mixing, the more cracks, the more volatility with winds (because of a more complex system is introduced). All of that impacting the lowest volume in that ocean, the most fragile we have ever seen it, then a tipping point could be reached. Whether it is this year or next year, or 3 years from now, it seems to me that's what people should think about. ... I would say there is 50-50 chance of that happening this year.
So predicting what is going to happen, seems to me, needs to take into account the state of the Arctic Ocean only, and its potential for a tipping point. A critical point, at which collapse occurs quickly.
I think that is what Peter Wadhams is going on about, and I think that's what he means. [emphasis mine]
Though I don't agree that predicting what happens only needs to take account of the state of the Arctic Ocean. I think jet stream changes will also be important, for example setting up repeated storms from the Atlantic.
Linear extrapolations of trends don't make much sense when this year's thickness vs area distribution is so different from the last 4 years.
Very important point. The already-meagre tools we have for following the melt season are not being processed by product algorithms adapted to the new conditions of the ice pack, weakening comparisons to the years for which they were developed and vetted.
Sentinel-1AB, as mosaiced at DTI, offers significant improvements in pack motion, dispersion, and resolution but it is not yet integrated into extent or volume products. The bus may leave the depot before its data can be deployed.
At the Arctic Sea Ice Forum Hyperion elucidates the interaction of Greenland's melt pool (Atlantic cold spot southeast of it) with the Arctic melting season.
Hansen 2015 warned about the danger of the meltpool south of Greenland. predicting that by covering the gulf-stream it could produce a world wide global warming effect up to ten times as much as our current greenhouse gas overburden. By reducing its [the Gulf Stream's] ability to radiate heat away into space. If this effect is kicking in, then we might have an explanation for why there appears to be a lot less ice nth of Svalbard and Franz Josef Land than Piomass is claiming. There's been persistent southerly's there for a while now, and waves created by them up to 3m spanking the ice in the vicinity. With the fragmented pack they are capable of penetrating perhaps 100km into the ice, and if gulf-stream waters are lurking below the cooler surface then considerable heat may be attacking the ice from below due to mixing processes. That meltpool also seems effective in pinning a low pressure system to itself and with the high pressure stalled over western Europe, the southerly's have been and look to want to continue winching all the air and humidity all the way up from the Caribbean and gulf of Mexico. [emphasis mine]
That prediction that by decreasing the warmth of the Gulf Stream from radiating to space the cold pool could have such a powerful positive feedback is news to me, and scary news. I've never heard of that effect being included in climate models.
The Arctic Sea Ice Forum general consensus is that 2017 is unlikely to be a new low.
Thawing Thunder says
I agree that there's a lot of thin ice, and that it's certainly distributed rather towards the edges. But if there's nothing strange going to happen soon, this season is running out of steam for a new record. If the anomalies show up that late like last year, only a cyclone could push the limits.
After 2012, the next four minima are not that far apart and 2017 is still on track to be in the range of that group of extremely low extent years. The widespread snow fall lowering albedo, the cold Atlantic, and the persistent cloudiness are not enough to prevent this cold year from achieving an extent on par with the low extents of recent hot years.