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.