Wednesday 28 June 2017

Watching the Arctic melt

From cryosphere to blogosphere, sea ice enthusiasts track Arctic melt

Arctic sea ice is more unstable than ever, and the ice may be melting toward a record in 2017, or not; one place to find out for sure is on the Arctic Sea Ice Blog and Forum.


  • Arctic sea ice extent has fallen precipitously since 2007, far surpassing all 18 computer models forecasting a drastically slower decline that wasn’t supposed to pick up speed until after 2050.
  • As a result of these startling annual events, a dedicated group of bloggers is trying to parse out what is really happening in the Arctic. Led by Neven Curlin (known as Neven Acropolis on the web), the Arctic Sea Ice Blog and the Forum is citizen science at its best.
  • Approximately 1,250 bloggers now gather annually online to work through all the conflicting seasonal Arctic evidence to make a forecast for the fate of the ice in September — will sea ice extent fall to a new low, impacting the world’s weather?

25 May, 2017


To some, watching sea ice melt — each floe dissolving slowly away into the Arctic Ocean — might seem the cold-weather equivalent of watching paint dry. But for the roughly 1,250 enthusiasts who gather in cyberspace on the Arctic Sea Ice Blog and the Arctic Sea Ice Forum each spring and summer, swapping satellite imagery, scientific intel, carefully plotted graphs, and strongly worded opinions, it can be as riveting as a Stanley Cup shootout.

A sampling: “HOLY SH*T: Fournier Triangulation Reversion Processed Image of the Lincoln Sea Ice reveals substratum of further leads and coastal regions made of pulverized pancake ice heading to Nares and Fram [straits],” wrote VeliAlbertKallio on June 6 in the Ice Forum’s 2017 Melting Season thread, which, at the time of publication, spans a whopping 44 pages.
User jdallen followed: “I find it striking how the ice along all the larger leads that opened up is disintegrating into what almost looks like long channels, 10-20 KM wide of slush reaching deep into the central pack. If it is all disintegrating into sub 100 meter floes, that does portend rapid melting out of those channels and exponentially increasing instability as they do.”
So goes the thread, with mostly ice nerds and citizen scientists — plus some seasoned Arctic researchers — chiming in with analyses riddled with jargon and acronyms baffling to novices, all arguing and offering evidence as to whether 2017 will set another record for low Arctic sea ice extent, or not.
Every now and then, their respected leader, Arctic Sea Ice Blog and Forum administrator and founder, Neven Curlin — who goes by Neven Acropolis on the web, or simply “Neven” — jumps in with this own updates, and sometimes a warning to temper those who offer the most outlandish forecasts.

A screenshot from Neven’s Arctic Sea Ice Blog in May 2017 at the start of this year’s melt season. The site has attracted some 1,250 enthusiasts who gather on the web to watch the Arctic icecap melt away each summer. Image courtesy of the Arctic Ice Blog

Neven cautions newbies that predicting Arctic ice melt is notoriously difficult, and that things may not always be as bad as they seem: “I’ve been in contact with David Schroeder and he has confirmed (or rather his model [has confirmed]) that this year (again) there is lesser melt pond formation than in years with record low minimums,” he wrote on June 12.
Fewer melt ponds early on, Schroeder says, might mean less extreme melt by September.

Following the ice


The Arctic melt season typically begins in May, and over the course of the summer months, builds in intensity toward a day — always, so far, during September — when the Arctic sea ice minimum is reached, marking the ice cap’s smallest extent for that year.
Since 2007, Arctic sea ice minimums have been dropping precipitously, and the ice is now declining at a rate of 13.3 percent per decade, relative to the 1981 to 2010 average. According to Arctic Sea Ice News, last year’s sea ice minimum was a near statistical dead heat with the second lowest ice record minimum, set back in 2007, when the Arctic ice covered only 1.60 million square miles (4.155 million square kilometers) in September. The lowest sea ice extent recorded to date came in 2012 when extent (usually defined as the area of ocean where there is 15 percent or more floating sea ice), fell to 1.31 million square miles (3.387 square kilometers).

Clark University’s Karen Frey and Luke Trusel work amid sea ice in the Chukchi Sea on July 4, 2010, setting up an instrument to measure the optical properties of melt ponds. The research is part of NASA’s ICESCAPE mission to sample the physical, chemical and biological characteristics of the ocean and sea ice Photo by Kathryn Hansen/NASA

The record to beat. The 2012 September minimum was the lowest since Arctic record keeping began. Scientists theorize that the loss of summer ice, and the opening up of the Arctic Ocean which absorbs more solar energy, is continuing to warm the Far North at an alarming and escalating rate. Image courtesy of University of Bremen

That’s partially why there’s so much excitement overwhat will happen this summer — will the sea ice extent continue in a downward spiral? Or will it rebound?
In March, the Arctic sea ice winter maximum extent set a record low for the third straight year, meaning the Arctic is already starting off with less sea ice this spring. Furthermore, online users have noted a strange, unsettling, quality to this year’s ice. In the past, the Arctic was made up of far more thick, multi-year ice. This year’s ice is thin and highly fractured, which ice bloggers point out could make current satellite sea ice extent measurements look far healthier than they actually are — a matter of quality, not quantity.
The argument goes that a battering from below and above by warmer Arctic Ocean and atmospheric temperatures this year could cause this fractured ice mosaic to just melt away by September, or summer storms could come along, as in past years, to smash the weak ice to smithereens.
But some experts believe otherwise, that we might actually be heading toward a better-than-normal sea ice extent come September. The lack of melt ponds in June — always seen in previous record low years — is one indicator scientists like Schroeder point to.
Though some bloggers argue fiercely back that maybe the lack of melt ponds this year is because the ice is just too fractured to hold melt water.
The most seasoned bloggers have learned the hard way that predicting Arctic ice melt accurately — with new weather patterns and phenomena emerging daily — is harder than getting the trifecta at the Kentucky Derby, Preakness Stakes and Belmont Stakes combined. (Though that doesn’t stop them from placing bets: in 2011, blogger Rob Dekker had a $10,000 bet going with blogger William Connolly.)

If you feel certain you know what’s going to happen, then you’re likely new to Neven’s Ice Blog.

Birth of an obsession


Twelve years ago, Neven Curlin, a Dutch translator living in Austria, developed an interest in global warming, skimming through blog after blog. When the first major sea ice extent record was set in 2007, stunning scientists, he began digging deeper, spending hours online discussing events in the Arctic.
In June 2010, the middle of the melt season, he decided to launch his own blog — a modest typepad account that’s changed very little in appearance since its inception. “I wanted to do something myself because I thought sea ice was such an important subject,” he says.


Melt ponds and ice floes pose a complicated puzzle for scientists. Understanding the complex mix of ice dynamics, sea and air temperature, ocean currents, solar absorption, cloud cooling, storms and other factors have made modeling and forecasting future Arctic conditions exceedingly challenging. Photo courtesy of Dr. Pablo Clemente-Colon, Chief Scientist National Ice 


While no one knows if a new record minimum will be set this September, the Arctic death spiral, as some bloggers call it, is showing no sign of abating. This chart, illustrating the September monthly average volume by decade and year from 1980 to 2016, clearly demonstrates the precipitous decline of Arctic sea ice volume over a mere four decades. Graph by Jim Pettit (jimpettit@gmail.com) sourced from PIOMAS

Though sea ice melt doesn’t affect global sea level rise (the ice is already floating atop the ocean and therefore doesn’t cause water to be displaced), disappearing sea ice has huge ramifications for global climate. The high reflectivity (albedo) of the white ice cap helps to keep the polar region cold, as sunlight is returned to space rather than absorbed by the surface. But as the ice melts, and more and more non-reflective blue water replaces ice in summer, the Arctic is warming — and so is the rest of the world.

Armed with only a high school education in physics and mathematics, Neven began resetting his “alpha brain” which benefits from an aptitude for languages, by intently studying weather maps. “Most of the analyses were simply comparing between years,” he says. “And when it comes to scientific papers I usually only read the abstract and discussion.”
Neven’s citizen science blog was an immediate hit among sea ice nerds, skyrocketing him to virtual stardom in the obscure subject. Three years later, Neven founded the Arctic Sea Ice Forum — an offshoot of his blog — to allow for a more vibrant discussion. Last month, the Forum had 2 million page views.
I thought at some point it’s going to stabilize, but it just keeps growing — even in winter. Arctic sea ice is getting more and more attention,” says Neven.

Is the smart money on melt ponds?


The growing numbers of people attracted to the Blog and Forum may be partly explained by rapid changes in the Arctic, as events there become more extreme and unpredictable.
So what’s really going to happen in 2017? Following Neven’s post about the lack of “melt ponding” this spring, Mongabay reached out to David Schroeder, a sea ice modeler at the Centre for Polar Observation and Modeling, and an avid reader of Neven’s Ice Blog.

Schroeder says that despite the fractured state of the ice, it’s best to remain cautious concerning a new record. Melt ponds form on Arctic sea ice when winter snow sitting atop it melts during late spring, which affects surface albedo by allowing more sunlight to be absorbed rather than reflected and therefore creating a positive feedback loop that exacerbates ice melt.
A multi-year ice floe, riddled with melt ponds, on the starboard side of the Coast Guard Cutter Healy, as the ship heads north into even thicker ice. Photo by Patrick Kelley, U.S. Coast Guard

In 2012, Schroeder, Danny Feltham and Daniela Flocco from England’s University of Reading developed a model to simulate the evolution of melt ponds and their contribution to sea ice melt in hopes of generating greater predictive accuracy regarding the September minimum. Until then, accounting for melt ponds had been difficult as satellite imagery often couldn’t discern between open water and melt ponds atop ice. When the team ran simulations of climate models without accounting for melt ponding, they found that September sea ice volume was predicted to be 40 percent greater
By looking at the positive feedback loops modelers can make a prediction as to what the sea ice state will be in the summer as early as May or June, though unpredictable weather by July will have a pronounced effect on the ice. “There’s a lot of impact from weather in the summer months, but we don’t know beforehand — we cannot predict the weather. However, it’s still possible to make predictions of this positive feedback through melt ponds.”
As already mentioned, this year, researchers are witnessing a substantial lack of melt ponds. Normally, Schroeder explains, melt ponds will first appear near the sea ice edge early in May, but so far, the only area with substantial melt ponding is around the Beaufort Sea, north of Canada.
It’s a bit of a surprise when you look at what happened with sea ice last winter,” Schroeder says. “We had a very, very mild winter and the lowest sea ice volumes ever according to the PIOMAS [Pan-Arctic Ice Ocean Modeling and Assimilation System] for April. The ice is thinner and therefore more likely to melt earlier, but the weather conditions in May were not so favorable for melting.”
In fact, in many Arctic regions this spring it was colder than prevailing climate conditions over the past 20 years. There was also more snow precipitation on the sea ice, which increased the albedo effect, meaning slower melt.
Graphs of forecasts by 15 computer models of Arctic sea ice melt at the September minimum through the year 2100, as compared to actual observed sea ice melt through 2015 shown in red. Scientists have been stunned by the drastic plunge in ice extent, which they’ve as yet been unable to explain in their models. Image and estimates courtesy of Neven Acropolis

Predicting the unpredictable


All that being said, it’s still way too early to tell whether 2017 will be spared a record-breaking year, and even the world’s top ice experts have been horribly wrong in the past. Ice modelers, for example, had repeatedly predicted in the past that the Arctic sea ice would stay intact and be safe from climate change until 2050 or later. Then in 2007, and again in 2012, the ice extent minimum fell far below all 18 computer models used by the Intergovernmental Panel on Climate Change, shocking experts right down to their socks.

So, back to 2017: what might lie ahead? “There are a couple things in favor of a record low year,” notes Neven, pointing to the mild winter and the low PIOMAS ice volumes Schroeder spoke of. But the things that stack up against a record are high terrestrial snow cover and cooler temperatures. “It’s been cold lately. The ice is melting less fast.”
Of course, all this can change in a matter of weeks. As we near July, snow cover will vanish and sea surface temperatures may increase. If the ice is as thin as PIOMAS says — 10 to 20 percent thinner than previous first-year ice — and it stays sunny, Neven believes we have “high chances of seeing a record low.”
It’s also possible that as the ice pack becomes increasingly vulnerable — like the fractured ice flowing out of the Far North right now — weather might not matter as much. Last year, for example, tied roughly with sunny 2007, even though June, July, and August 2016 were cloudy.
A melt pond atop Greenland’s sea ice. Photo by Michael Studinger, NASA GSFC

Ice fatigue


On November 20, 2016, Neven took to his blog with a surprise announcement. He wasn’t sharing a new forecast, but rather declared he would be taking a sabbatical.

“I have been struggling with Arctic burnout since 2012,” he wrote. “On the one hand it’s caused by everything that has been and still is going on in the Arctic. The learning curve, the excitement, but most of all the depression that comes with watching this steamroller just plough forward, is taking its toll.” Then, he linked to the Genesis song “
It’s Gonna Get Better.”

His post received 171 comments.
Talking with Mongabay, Neven chalked up his temporary absence to a couple factors including the workload (“Even though the ice melts slow, there’s so much information and so many things to watch for.”), and the despair (“On the one hand, it’s exciting if spectacular things happen, but if you sit back and think about the implications and potential consequences, it can be a bit depressing.”)
Last summer, when Andrew Slater died, a young cryosphere scientist whose work Neven had followed closely, it all became too much. “It made me so sad, and I thought maybe it’s time for a break.”
By and large, he has stuck to his planned sabbatical over the past seven months, averaging just two to three posts per month, and allowing his fellow bloggers to take on much of the heavy lifting on the Ice Forum and Blog. But as melt season ramps up, it’s been harder to stay away, he says. And even though he’s blogging less, Neven has stayed active on the Forum.
He is also using his time away to think more optimistically, considering where to take the website in the future. “I don’t want to just describe the train wreck in slow motion — I don’t find that very satisfying,” he concludes. “I’m hoping I’ll get some new ideas… about how to connect what is happening to a more positive outlook. I always like to insert a bit of humor in the blog, too.” Hoping against hope, Neven wants to believe It’s Gonna Get Better.


The crew of the U.S. Coast Guard Cutter Healy dip their feet in a melt pond during Ice Liberty — a few hours during the ICESCAPE mission when scientists and crew could take a break and relax (or throw snowballs) on the sea ice. Photo by Kathryn Hansen/NASA

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