ASI 2016 update 1: both sides

During the melting season I'm writing (bi-)weekly updates on the current situation with regards to Arctic sea ice (ASI). Because of issues with data based on the SSMIS sensor aboard DMSP satellites, I mainly focus on higher-resolution AMSR2 data from the Japan Aerospace Exploration Agency (JAXA), as reported on the Arctic Data archive System website. I also look at other things like regional sea ice area, compactness, temperature and weather forecasts, anything of particular interest.

The animation on the right consists of NSIDC
sea ice concentration maps, one for each ASI update.

Check out the Arctic Sea Ice Graphs website (ASIG)
for daily updated graphs, maps, live webcam images, and
the Arctic Sea Ice Forum (ASIF) for detailed discussions.

May 27th 2016

After an unprecedented warm winter and an unprecedented early opening of the Beaufort Sea, the 2016 melting season isn't showing any signs of shrugging off the 'unprecedented' label. What has struck me most so far, is that unprecedented things have been happening on both the Pacific and Atlantic side of the Arctic.

I've been closely observing events in the Arctic for almost a decade now, and have been writing about them since 2010, and during that time I have gotten used to this sort of see-saw, where fast melting on one side of the Arctic would be compensated by events unfolding slowly on the other side of the Arctic. But this year is different. This year the ice pack is under attack on both sides of the Arctic.

I have written separate blog posts to describe these events (see here and here), and in weeks to come these ASI updates will provide a comprehensive overview on what is happening to the sea ice in the Arctic, and how this melting season is unfolding.

Sea ice extent (SIE)

Let's jump right into it. Here's the latest JAXA SIE graph:That gap is pretty intense. I wasn't kidding when I said 'unprecedented'. Last year - orange line - was already quite spectacular, but this year is crazy.

As commenter Jim Pettit wrote on the Arctic Sea Ice Forum earlier today:

• 1,220,829 km2 below 2000s average for this date.
• 763,419 km2 below 2010s average for this date.
• 529,970 km2 below 2015 value for this date.
• 1,090,443 km2 below 2012 value for this date.

• Lowest year-to-date (01 January - 26 May) average.
• Lowest May to-date average.
• Lowest value for the date.

• 92 days this year (63.01% year-to-date) have recorded the lowest daily extent.
• 27 days (18.49%) have recorded the second lowest.
• 14 days (9.59%) have recorded the third lowest.
• 133 days in total (91.1%) have been among the lowest three on record.

More than 1 million km2 lower than record minimum year 2012. This sea ice concentration difference map, as provided by Dr Andrew Slater (NSIDC) on his personal website, shows in which regions there is less ice this year than in 2012 (red):

2012 sea ice extent started to drop very fiercely in the first half of June and it will be interesting to see how much smaller the gap will get, but I expect 2016 to stay in the lead for quite a few weeks to come, even though 2015 levelled off quite drastically during June. Too much has been happening so far.

Regional SIE and SIA

Here's a map that shows the names of all the different regions in the Arctic. You can find it at the top of the Regional Graphs page on the Arctic Sea Ice Graphs website:

The sea ice concentration difference map above already hinted at it, but here's what I mean with both sides. First the regions on the Pacific side of the Arctic, and for that I use Wipneus' home-made regional sea ice extent maps:

With the Bering and Okhotsk Seas devoid of ice (just as fast as last year), the edge of the ice pack is now retreating fast in the Beaufort and Chukchi Seas. For more details see last week's Beaufort final update. As you can see, SIE in the Beaufort Sea is extremely low for the time of year.

Meanwhile, on the Atlantic side:

It's the Barentsz Sea that's extremely low here, and extent also has started to drop in the Kara Sea (I expect it to follow the 2012 and 2015 paths, given the state of the ice south of Novaya Zemlya). The ice in Baffin Bay is also melting out at a record pace, but what is really intriguing, is that the ice in the Greenland Sea is at record low levels.

Given the high pressure over the Beaufort Sea, the Beaufort Gyre has been doing its thing for a couple of weeks now, which means ice on the Atlantic side of the Arctic gets pushed into the Greenland Sea, via Fram Strait. Extent levels should be at least high as they were in 2012, but they are record low!

As I said over a month ago: This is evidence of warm waters having been pushed northwards into the Arctic by the warm West Spitsbergen Current. This increased ocean heat flux could be another joker up this melting season's sleeve, and it explains how ice levels can be so low on both sides of the Arctic.

Weather conditions

And now for the weather...

This animation of Danish Meteorological Institute SLP images shows the distribution of atmospheric pressure during the past two weeks:

  High pressure has continued to dominate the Arctic, though the anti-cyclones aren't as strong and big as a few weeks ago when they spectacularly pulled the ice away from the North American coasts. Still, high pressure means relatively clear skies, and as the Sun is pretty high up in the Arctic sky (one month before the Solstice), a lot of solar radiation is getting soaked up by all that open water in the Beaufort and Chukchi Seas, causing the first melt ponds to form on the ice pack and snow to melt on the land (also at record lows for the Northern Hemisphere).

Here's what the ECMWF weather forecast model has in store for the coming 6 days (click for a larger version, and go to the ASIG Forecasts page for daily forecasts):

1035 hPa for the coming three days over the Beaufort Sea isn't good news for the ice, especially not combined with those lows over the Siberian coast, which makes for a classic Arctic Dipole that strengthens the Beaufort Gyre, pulls the ice way from the American coast, and pushes it out towards that (warm) Atlantic. Expect big drops in extent.

The configuration changes somewhat for days 4-6 in the forecast, which becomes less reliable the further out you go. But let's hope for a reprieve, as this is the worst possible scenario for the ice right now.

It's not all about solar radiation - though a lot is -, surface air temperatures also play an important role in melt pond formation which is such a crucial factor in how a melting season plays out. If you have lots of melt ponds, a large amount of solar energy gets soaked up which helps maintain melting momentum at the later stages of the melting season.

Unfortunately, temperatures in the Arctic have been unprecedented as well this year so far, with no single instance of the temperature trend line dropping below average this year so far on the DMI mean temperature graph for the area above 80 degrees northern latitude (see map):

This is something else I have never seen before, and I will try to make a comparison graph one of these days to show you how unusual this is, even compared to all those other unusual years in the past decade.

Here are the GFS weather model actual temperature forecast maps for the coming week, as provided by the excellent Climate Reanalyzer website (I'll be using temperature anomaly maps in future ASI updates, but these actual temperature maps nicely show the distinction between freezing blue and melting green):

In the coming week, freezing temps are going to disappear almost everywhere (a bit later than last year), but do also check out those 20-30 °C temperatures over Alaska and East Siberia. This will finish off the snow there, after which the land will warm up, further increasing temperatures over the Arctic Ocean and the ice pack.

Unfortunately, I have no info right now on sea surface temperature anomalies, as the people at the DMI have - for no apparent reason - discontinued their excellent and visually appealing SST anomaly map, which I have used for years. I'm still looking for an easy substitute to use in upcoming ASI updates, and will hopefully find something, as my guess is that SSTs are also running real hot right now, compared to those of previous years.

Conclusion

A melting season can be divided into several segments that all influence the process and final outcome. The winter or freezing season that determines initial sea ice conditions, is followed by a transition phase where leads still freeze over, but ice hardly gets any thicker. Then, as the melting season gets under way, melt ponds start to form on the ice floes, soaking up solar energy and building up melting momentum.

If you would write a scenario for how the first ice-free September comes about, it would look something like this. I don't think Arctic sea ice extent will dip below the 1 million km2 mark this year, simply because the ice in the Arctic's core is too thick to melt out. Never say never, though. It is the Arctic after all, and things have been progressing much, much faster than people (including scientists) thought was possible just a few years ago.

Considering what has happened so far, a new record minimum is a distinct possibility though. If a lot of melt pond formation occurs this month and the next, it will take some extremely cloudy and cold weather during July and August to prevent records from being broken. And even then the minimum will most probably be among the lowest on record. So melt pond formation is what I will be focussing on in weeks to come.

This melting season is looking spectacular and exciting, but at the same time depressing and frightening, given the almost certain negative effects of this magnitude and rate of change. Let's hope for the best.

Comments

[D]

-Fish here - Yes, the heat content of the water entering the Arctic from the Atlantic has been melting out the ice that approaches the Greenland sea. As storms enter the Arctic on the Atlantic side the waves and winds stir up the water and the ice front retreats back towards the pole.

Wave 1 driving from the El Niño revived the thermohaline circulation and the warm water than had built up off of the Canadian maritimes a few years ago in now entering the Arctic.

And in the Pacific the PDO has shifted to the warm phase so the warm water is spinning up the coast of Alaska.

As Levi Cowan at TropicalTidbits.com has noted in his Atlantic hurricane forecast this is an extremely unusual ocean heat pattern. I note that this ocean heat pattern is exceptionally bad for Arctic ice because it is bringing heat to the Arctic from both the Atlantic and Pacific.

The GFS and ECMWF weather models have been struggling, showing extreme inconsistency, with forecasting the Beaufort high beyond 5 days. It's still going strong. Not good.

[Susan Anderson]

Just looked up hurricane seasons for 1998 and would hazard a guess we are in for some Atlantic ocean venting in the form of big storms further south. I'm not sure how that affects the north but it might be worth watching.

[Jim Hunt]

This may seem wildly off topic, but since "Fish" mentions the matter, the National Hurricane Centre is currently forecasting "90% chance of tropical cyclone formation" in the North Atlantic over the next 48 hours:

http://www.nhc.noaa.gov/gtwo.php?basin=atlc

The Atlantic hurricane season officially starts on June 1st. Perhaps slightly more on topic, recall that Hurricane Alex formed on January 14th and then headed straight for Greenland.

"Extremely unusual ocean heat patterns" beget "weird weather" which begets more heat heading to the far North?

[wayne]

lately ECMWF was far better than GFS for the Arctic, D

It failed projecting the Beaufort High on several occasions, unlike European model.

Is it because GFS is less holistic? There are places with lot of snow despite record low snow extents. This is why my projection more than a month ago, still holds, ECMWF is more aware than GFS in my estimate. Bravo Europa!

[jdallen_wa]

Chris and Susan - yes, that storm brewing up off of the US Eastern seaboard is alarming.

Water temperatures there are already running in the upper 20's to almost 30C.

That heat translating into the Greenland/Norwegian/Barents seas via storm systems will make a big problem worse.

[Lawrence Martin]

MODIS side comparison of the Beaufort Sea for May 21 2016 and June 21 2015.

Alarming?

http://www.arctic.io/explorer/8-8/2016-05-21;2015-06-21/6-N75.7439-W143.49899

[D]

Note Sentinel imagery at DMI that shows the ice arch in the Nares strait is starting to break up. Currents on the northwest side of the arch have broken off a large sickle of ice and open water is showing on the landward side of the arch.

As to the Atlantic, 81.7 F temps are now showing at the buoy on the shoals off of Cape Hatteras. The Gulf Stream is steaming.

[D]

Agreed, the ECMWF has been better than the GFS on the Arctic for the last 2 months but I don't know why. The Euro model has also been better on weird tropical systems like Sandy off southeast coast of the U.S.

[crandles]

DMI SST map back up.

[Yvan Dutil]

D, it is not very difficult to understand why : the ECMWF is the best model in the world.

It has more resolution, more data assimilation and more physics than any model. European have the largest computer band in the world to run it.

And, they have improved it recently.

[Artful Dodger]

Hi Neven,

Good update, and Welcome to the Scorch!

Indeed, this pre-viz of dramatic Arctic sea ice collapse was created by Scientists in 1969:

Scorchio!

Cheers,
Lodger

[Rob Dekker]

Thank you Neven. Very good summary of the unprecedented decline in sea ice going on on two sides of the Arctic.
There is a third side that still has instills some hope : The Siberian side.

So far, Siberian land snow cover has been holding up (at least better than the American side) and ice in the East Siberian Sea appears to be "average" at least in volume and extent. And the Laptev has been holding up pretty well too.

Do you think that this third side of the Arctic will slow down the decline, and possibly prevent the Arctic sea ice from what appears to be an unprecedented collapse this year ?

[Neven]

And in the Pacific the PDO has shifted to the warm phase so the warm water is spinning up the coast of Alaska.

Indeed, Fish. Who knows how much heat is coming in through Bering Strait. I wish we had some real-time(ish) mooring data on ocean heat flux. Maybe I'll try and ask some scientists if they know anything.

DMI SST map back up.

The SST map has been back up for a while, and it includes ice temperature now (you have to click one day backwards to see it), but what I need, is the SST anomaly map. The DMI isn't answering my mails, so I'm not expecting it to go back up this melting season. But it would be great if it would.

Do you think that this third side of the Arctic will slow down the decline, and possibly prevent the Arctic sea ice from what appears to be an unprecedented collapse this year ?

Let's hope so, Rob!

Siberian snow may linger longer around the Yamal peninsula, but given the forecast I think that snow in eastern Siberia is toast.

As for the sea ice, here's the current situation in the Laptev and ESS:

Laptev sea ice will melt out eventually, so if it's melting slow now, that means it's 'piggy bank ice' that 2016 can cash in later. But slow melting may protect the CAB ice on that side, of course.

I believe the East Siberian Sea is the only region, next to the Central Arctic Basin and Canadian Archipelago (okay, and the Greenland Sea), that doesn't have to melt out completely. As the image shows, only 2012 melted out completely in recent years, which means CAB ice is safe behind that too.

Given that both PIOMAS and CryoSat2 think that ice is somewhat thicker on the Siberian side, we can only hope that this will slow down losses enough for the CAB ice to be left alone, so to speak.

But our best hope is for cloudy, cold weather like we saw in 2013 and 2014. If we get 'average' weather, it will be bad enough. If we get something like 2007 or 2012, things are going to get ugly. Spectacular, but ugly.

[Ac A]

Hello Neven,

great summary, as always! What aboout "blue ocean" event? I can only quote Peter Wadhams, who told me few weeks ago at the ESA Living Planet Symposium in Prague:

"It could happen this year."

Best,

Alex

[Neven]

Hi Alex,

Cool, you were in Prague. I wish I could have gone. There were a couple of interesting presentations.

What aboout "blue ocean" event? I can only quote Peter Wadhams, who told me few weeks ago at the ESA Living Planet Symposium in Prague:

"It could happen this year."

From the conclusion: "If you would write a scenario for how the first ice-free September comes about, it would look something like this. I don't think Arctic sea ice extent will dip below the 1 million km2 mark this year, simply because the ice in the Arctic's core is too thick to melt out. Never say never, though. It is the Arctic after all, and things have been progressing much, much faster than people (including scientists) thought was possible just a few years ago."

[Neven]

Note Sentinel imagery at DMI that shows the ice arch in the Nares strait is starting to break up. Currents on the northwest side of the arch have broken off a large sickle of ice and open water is showing on the landward side of the arch.

I've just written the following in the Nares Strait thread over on the Forum:

Here's an animation showing the last 5 days on LANCE-MODIS. I think that arch looks stable enough, and the ice will have to turn blue before it breaks. There was a polynya in a similar position back in 2012, and that's where the arch failed first, but this year's arch is a bit further back, so I'm not sure if the polynya will impact that corner. Either way, I think it's going to take a couple of weeks for the arch to break, probably before June is out.

[Jim Hunt]

The Sea Ice Prediction Network has announced the call for contributions for the 2016 Sea Ice Outlook June report:

https://www.arcus.org/sipn/sea-ice-outlook/2016/june/call

Pan-Arctic and Alaska Regional Outlooks and gridded fields will be accepted for the 2016 June Outlook. We particularly encourage submissions for the Alaska region (i.e., Bering, Chukchi, and Beaufort seas). Submissions that include spatial forecast maps are also encouraged. Detailed guidelines for contributions are below. This year, in addition to a short executive summary and summary of methods, we require information about datasets used for your submission. We encourage all past contributors to submit Outlooks this year and we also hope to see new participants.

There is already a "Pre-Season and Informal Contribution" available for download from:

https://www.arcus.org/sipn/sea-ice-outlook/2016/informal-contributions

Three long airborne ice thickness surveys were carried out in the Northwest Passage and Canadian Beaufort Sea by York University in early April 2016, and compared to similar surveys performed in late April 2015. Results show that ice thicknesses in the Northwest Passage were similar in both years, although there was less multiyear ice (MYI) in 2016.

In the Beaufort Sea, the thickness of MYI was similar to 2016. However, due to strong divergence and export, first - year ice (FYI) was much thinner than in 2015, giving rise to expectations of earlier FYI melt and disappearance in 2016 than in 2015. However, multiyear ice may survive as long as in 2015, and may thus retard the overall retreat of the ice edge as it did in 2015

For any others interested in Atlantic cyclones, there is now a tropical storm warning in effect for "Savannah River to Little River Inlet South Carolina":

http://www.nhc.noaa.gov/text/refresh/MIATCPAT2+shtml/281150.shtml?

[Ac A]

Hi Neven,

exactly, I agree with your conclusions. Regarding the ESA meeting, I liked the Jason Box presentation, but most of the others were boring (even those about Arctic etc.), so I just read your articles ;-)

Best,

Alex

[Hans Gunnstaddar]

I'm just going to throw my 2 cents in now early in the melt season, because I don't see the following possibility being suggested.

Even in a downward spiral there are going to be flow ranges that will occur lasting several years. 2012 was so much lower than the previous or post range, it seems more statistically likely 2016 minima at worse will be about the same as 2012's record.
If it is about the same, then that may indicate ice extent is settling into a new lower minima range.

[Rob Dekker]

Interesting, from the Arcus "Informal Contributions" site :

Three long airborne ice thickness surveys were carried out in the Northwest Passage and Canadian Beaufort Sea by York University in early April 2016, and compared to similar surveys performed in late April 2015. Results show that ice thicknesses in the Northwest Passage were similar in both years, although there was less multiyear ice (MYI) in 2016 (Section 2.2). In the Beaufort Sea, the thickness of MYI was similar to 2016 (Section 2.1). However, due to strong divergence and export, first‐year ice (FYI) was much thinner than in 2015, giving rise to expectations of earlier FYI melt and disappearance in 2016 than in 2015.

Seems that that (earlier FYI melt) is exactly what has led 2016 to where it is now.

[Rob Dekker]

And also interesting that thin FYI is blamed on "strong divergence and export". Divergence to where ? And export to where ? And how do you know ?

As if the record high temperatures during winter had nothing to do with it.

Bizarre.

[navegante]

@crandles I just visited the DMI SST site and shows a map from March as if it was Today's. Are there two diffetent urls perhaps?

[Jim Hunt]

Rob - "Export to where?"

The Siberian coast of the Chukchi Sea? From CryoSat 2 at the end of April:

[D]

-Fish here- Agreed Jim. I think that Cryosat 2 has the best map of thickness available now. The map above fits what's been going on with the weather. Before the persistent Beaufort high set up in early spring the European side of the Arctic (and the north Atlantic) was very stormy. Warm water from the Atlantic worked its way into the Barents sea. Ice did not build up on the shores of Siberia. Instead it piled up north of the Fram strait on the way out of the Arctic.

Weather models now have the high breaking down soon but the Siberian side will get very warm. The best hope for the ice this year, in my opinion, is inconsistent weather and a slow down of transport.

[P-maker]

Navegante,

“Are there two diffetent urls perhaps?”

Neven,

In a Neoliberal context, DMI is heavily financed by lucrative advertisement contracts. Hence DMI is trying to attract traffic to their web site, which will be exposed to ads. Recent examples on their web site were holiday offers on a low-lying island in the Indian Ocean and another ad about how to negotiate financial risks these days.

If you go to this site: http://ocean.dmi.dk/satellite/index.uk.php and choose ‘Two days before Tomorrow’ (i.e. yesterday), you will get something like an observation-based SST anomaly map for the Arctic, that is if you get your set points right.

DMI has unfortunately decided to extend their anomaly scale to the extremes of -50 deg C and + 20 deg C – both are meaningless today and they will only give you a pale yellow and a pale green approximation of reality.

Sorry to say this again, but business interests have taken over both the Weather Channel and now apparently DMI as well…

[Julz]

Hi folks,

just a quick question, for the past couple of days, when I go onto the Jaxa Archive Data System I find it just stalls for ages trying to load and then after a while I just get a dialog box that says "ads.nipr.ac.jp says: error" [OK].

Is anyone else seeing this?

[Chris Reynolds]

Rob,

I have come to the conclusion that temperature had little to do with the current state of Beaufort.
http://dosbat.blogspot.co.uk/2016/05/how-did-beaufort-get-in-this-state.html
It was the wind that was anomalous in that region, not the temperature.

Temperatures have had minimal impact over the rest of the Arctic Ocean sea ice. This is because although anomalies and FDDs were high, and temperatures were 'warm', temperatures were still cold enough that the limiting factor in ice growth was predominantly ice thickness (not air temperature).

[Chris Reynolds]

Thanks for the SIPN heads up Jim,

It's good to read from Haas that my finding of wind as the reason for the state of Beaufort is what they assert. It will be interesting to see if the MYI has a stalling impact, by my reckoning if it's going to happen it should be causing a stall in extent loss by mid June. The ice edge has stopped progressing poleward and now seems to be going towards Chukchi.

I'll get my entry off tomorrow.

[NeilT]

My first instinct, on reading your post Chris, was to think that it had to have something else to do with it. Such as anomalously thin FYI is such large amounts that there was ability for the wind to push the MYI somewhere.

Reading your post it seems that you also came to that conclusion. That the extreme warmth of the winter season left the FYI in such a weakened state that the constant strong winds found little resistance as they pushed the MYI offshore.

Creating, as it would, areas of extremely thick ice. Of course that extremely thick ice would still be FYI which is of higher salt content and therefore more susceptible to rapid melting when the sea warms in the summer.

So whilst I agree that the winds are the main driver for the huge area of sea opening up, rather than radical melting, what you don't really address is that the state of the FYI, driven by the extreme winter warmth, was not able to resist the winds.

For instance the last time, on your chart, that there were the same anomalous high winds, was in the 1990's. However the Arctic ice was a totally different beast in the Beaufort in those days.

At the end of the 2015 melting season large chunks of MYI were locked in place by rapidly freezing FYI. FYI which did not gain the strength to resist even moderate wind on MYI with a higher freeboard.

In short, the wind was able to create the space because there was room to move.

Putting the two together gives you a complete picture which fits the ice dynamics of the 21st century.

[Neven]

Creating, as it would, areas of extremely thick ice.

So, basically the entire area of ice that is now open water has been piled atop the rest of the ice pack, so to say?

I find that hard to believe. All that movement and mixing has to result into some melting as well. It can't just all go into ridging and slabbing.

Or is it because the entire ice pack made room by moving towards the Atlantic (where ice melted out)?

Like Rob says: "Divergence to where? And export to where? And how do you know?"

It will be interesting to see if the MYI has a stalling impact, by my reckoning if it's going to happen it should be causing a stall in extent loss by mid June.

That depends on 1) how thick that ice is (and it seems to be thinner in the Beaufort than any other year), 2) weather, of course.

Normally, if Beaufort MYI is thick, weather conducive to melting can't prevent extent decrease to stall. Instead the energy goes into melting momentum which assures (almost) extent decrease in July and August.

If Beaufort MYI isn't all that thick (because of winter temps, little import from the CAB), weather conducive to melting excludes a stall.

This is all (my) theory, of course.

[Neven]

Never mind the great unknown: Pacific Ocean heat flux.

[NeilT]

No I didn't think it all ridged and slabbed. But I did think quite a lot. Which leaves the younger ice more exposed in water and air without it's snow cover.

Whatever happens it's going to be interesting.

I was just musing on the changes of the ice dynamics with a thinner, less resistant, pack and how it responds to extreme weather.

[Neven]

Thanks, Neil, it's thought-provoking.

[bobcobb]

Ac A,
What did Box say? I like that guy

[wayne]

Neither one or the other, the main pack moves faster because the very ice is warmer,the frozen leads are thinner, they collapse and melt earlier. And of course there is melting of ice in 0 C waters, yet to be industrial scale, but present. Consider these days like early August, which means the minima 45 days away is extended by 60.

There is action everywhere of course, Hudson Bay fascinates as always, but ice mobility is not only for the Beaufort Sea, the main Arctic Ocean ice pack spring break occurred about 1 month early, it shows just as well on top of the Greenland Sea:

http://eh2r.blogspot.ca/

[Colorado Bob]

Arctic Sea Ice Extent on May 27 record low. Already at end June average

https://twitter.com/tveitdal/status/736886879715504128/photo/1?ref_src=twsrc^tfw

[AbbottisGone]

Consider these days like early August, which means the minima 45 days away is extended by 60.

<<

This can't be good! Where is the fiduciary responsibility?

[Tom Zupancic]

As a scientist observer, just a couple of comments... given that the system is complex, I would suggest that too much attention has been focused on melt pond formation. Rather, given that it takes heat to melt ice. In the historically warm present, does that mechanism matter this year when so much open water that can absorb solar irradiation exists? Also,so much new energy has been accumulated in the oceans. Thus, regardless of tropospheric energy levels, the present is unique. (ie, heat already present in water might simply move north...) That is, while weather has historically been a key factor in determining Arctic Sea Ice melt, the heat that has accumulated in the oceans is a fundamental driver. Also, the exceptional heat in the troposphere right now is hard to ignor. The heat accumulated in the ocean/climate system is clearly substantial. As a specific comment/question, I would suggest that given the complex nature of this system there are multiple alternative hypotheses to understand the present.

[Rob Dekker]

I read the Haas paper in more detail, and they do acknowledge that FYI in between MYI flows is thinner in 2016 than in 2015 :

that mode is somewhat thinner than the mode at 2.1 m found in 2015, indicating that old FYI in 2016 is ≈20 cm thinner than in 2015

and another observation suggests that FYI in 2016 was too weak to form elsewhere :

...almost complete absence of the mode at 2.1 m, which in 2015 and before is representative of old FYI formed since the onset of ice formation in the previous fall

But the most important issue is that their observations are in April 2016. This was during the time that the Beaufort was already breaking up into pieces. Neven even did a full blog post on that :
http://neven1.typepad.com/blog/cracks-and-leads/
with a great compilation of images over the month :
http://neven1.typepad.com/.a/6a0133f03a1e37970b01b8d1ea2b1e970c-pi

In 2015, that break-up happened much later (mostly in May).
This early breakup in 2016 obviously led to polynia in April, that froze over and led to that "much thinner FYI" that shows up in their density distribution graphs.

So technically they are correct when they say "due to strong divergence and export, first‐year ice (FYI) was much thinner than in 2015,", but by failing to address a cause for the weak state of FYI, nor the breakup that was on-going during their measurements, they miss the overall picture of the state of the ice, which is much better worded by Meier in Neven's post :

This region used to be mostly multi-year ice, which is quite a bit thicker. Now, most of the Beaufort is seasonal, first-year ice. The thinner ice is weaker and more easily broken up by the winds.”

Which is consistent with Chris' and Jim's assessment that yes, the winds played a significant role this year in the Beaufort's state. But also consistent with Neil's notes up above, and my contention that weak FYI due to high winter temperatures played a role too in this year early disintegration of the Beaufort.

As for the wind movements and melting that followed, the "melting season" thread in the Forum has a good discussion going on.

[Chris Reynolds]

Neil T,

I did address the winter warmth, but upon re-reading I could have been more clear.

Take the NCEP/NCAR surface temperature anomalies.
https://4.bp.blogspot.com/-xIh6bTNYoCs/VzDhwr0lcoI/AAAAAAAAC88/V7d0q6VJ0wYxgp5cEF3Mmz54AnNj7B4egCLcB/s1600/Sfc%2BTemp.png

Note that 2016 was not much above 2015 and 2014.

Now look at PIOMAS Gice for the end of April.
https://4.bp.blogspot.com/-mJRdFEQY3ug/Vyo0B4PKyVI/AAAAAAAAC7k/azEYCby_cZkFDGAwnEU7pxZO9idfgM98gCKgB/s1600/GICE%2BBeaufort%2Btimeseries.png

If temperature is the explanatory variable then 2015 and 2014 should be in as poor a state as 2016, they weren't. And ice state from PIOMAS Gice in December doesn't show severely thinned ice, this is indicated by Beaufort Volume expressed as a difference from the 2007 to 2015 average for each month.
https://4.bp.blogspot.com/-aeRgOJPGX64/VzDVJucUdkI/AAAAAAAAC8o/iI-WNlOIxZscHZXX_fEChS-uvbDrM6rfACLcB/s1600/Volume%2BDelta.png

Strong winter divergence in an of itself can explain very thin ice, because the divergence drives winter open water formation. This open water freezes rapidly in the winter cold but the ice is moved on and new open water rapidly freezes. The end result is that the ice doesn't sit around to thicken in the region from which it is being exported, so the region starts the summer very thin.

And as for the impact of the winter warmth. The following table takes the whole region north of 70degN using NCEP/NCAR temperatures and the simple model of sea ice growth.
https://2.bp.blogspot.com/-kobdHYuSsIU/Vtm8C9odcaI/AAAAAAAACyM/FQILXi6zxtU/s1600/Jan%2BFeb%2BIce.png

The anomaly of Jan/Feb temperatures is huge, January was 5degC above 2007 to 2015, February 4degC above. But for those months the actual temperatures were -18 and -20degC, which is still cold enough to draw heat flux through the ice and cause ice growth. Assuming ice that has grown to 1m thick from September through December, the January and February cold causes a thickening of a further 60cm for the 2007 to 2015 average. For 2016 there is still 50cm of growth. So the warmth of 2016 causes only a 10cm (17%) thinning.

Neven,

Have you looked at the ice edge movement just off Banks Island versus the ice edge movement along the Alaskan coast? I have a blog bost coming up, did the work last night. Extent loss in Beaufort is from extension of the Polnya along the Alaskan coast, movement polewards from the region off Banks Island has stalled already as it hit the region of MYI shown in Cryosat2 and ASCAT. I'll post later today.

[Chris Reynolds]

Neven, Tom,

Ice state from PIOMAS and Cryosat 2 does not support a record year IMO. There is ice from the coast of the Canadian Arctic Archipelago to the Siberian coast that is pretty similar to recent years. This should mean my prediction this year (4.0 to 5.3 million kmsq Sept NSIDC Extent) is fairly safe, or at least not guaranteed to fail. However I am not so confident; I don't know how much the warmed waters in the north Pacific along the western coast of the US and Canada will play a role, and to what depth Atlantic waters are anomalously warm. Indeed whilst concentration often falls on the factors we can readily measure, as Spielhagen 2011 (Enhanced Modern Heat Transfer to the Arctic by Warm Atlantic Water) shows, Atlantic water is anomalously warm in the context of the last 2000 years.

Rob,

As is often the case, long term pre-conditioning plays a role in the transition to a predominant first year ice state. However the divergence can explain the first year ice state as I explained to Neil above.

[Rob Dekker]

Chris,
The Haas paper suggests that in 2016, FYI did not develop at all in the Beaufort :

The density distribution picture is dominated by the ultra-thin ice that was forming while the Beaufort was breaking up in April, suggesting that there simply was not enough 'cold' to go around to withstand ice movement.

[Arcticio]

Re CryoSat, using differently advanced snow models CPOM and AWI publish deviating results. Have a look at this presentation: http://epic.awi.de/40803/1/1604_Nicolaus_EGU_PK_small.pdf

[John Christensen]

Regarding DMI SST maps: I have been in touch with some of their ice researchers previously, so will reach out to them.

P-maker,

I don't really buy your conspiracy theory regarding DMI, but you probably don't really either.. ;-)

[wayne]

"does that mechanism matter this year when so much open water that can absorb solar irradiation exists? "

Tom,

Bingo, we are looking at indeed a complex system. If there is very little net long wave radiation escaping upwards from the sea under the ice, which naturally occurs in the spring due to solar input. There is one of 2 things which may happen, if the sea ice is thicker and there is lots of clouds, the ice will survive, but if it is rather more 1st year thin, sea water temperature increase, however apparently small, matters, it warms from its larger underlying thermal heat source even when there is no open water. Add more solar heat because there is more open water in Beaufort - and - elsewhere including the North Atlantic:

http://eh2r.blogspot.ca/2016/05/2nd-remarkable-retreat-front.html

The result would be a warmer underlying sea making the over all thinner sea ice very vulnerable.

[P-maker]

John, point taken

Could DMI have run into an simple "overflow" problem?.

Browsing through the various DMI charts, I came to notice that SST anomalies off SW Alaska and in the NE Baltic both exceeded 4 deg C yesterday. I also noticed that the SST anomaly scale on the Arctic SST anomaly map (yesterday) was different from the other anomaly scales.

Hence I came to think of a simple programmer's bug, but who would have thought about that without your Divine intervention John?

[Chris Reynolds]

Rob,

As I have already shown above, the 'lack of cold' this year was only marginally more than in 2014 and 2015, yet those years didn't see similar conditions. The cold is not the issue, the simple model of sea ice growth demonstrates that.

It was wind driven divergence, driven by a dipole formed by the Beaufort High and the Aleutian Low, that was highly anomalous this year.

[Aaron Lewis]

Tom,
Fully concur that ocean heat drives everything.

However, some of that heat is advected into the the ocean by surface water and even deep plumes of permafrost melt.

[John Christensen]

I agree with you on this Chris; looking back at the CT charts for Beaufort, it is clear that also in the 80's and the 90's, the wind and/or the Gyre would in some years pull/push the MYI away from the coast during winter or spring, leaving only very fragile FYI, which causes open water in the early spring and minimum to get low as well:

http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/recent365.anom.region.11.html

I would therefore also question the remark referenced further up:

"This region used to be mostly multi-year ice, which is quite a bit thicker. Now, most of the Beaufort is seasonal, first-year ice. The thinner ice is weaker and more easily broken up by the winds.”

If this region was 'mostly multi-year ice' in the 80's (and the MYI stayed in place during summer), then it would not be possible for the Beaufort sea ice area to get reduced as much as it did in some years.

That said, this year we have had the combo of weather patterns and temperature to cause the open water area to expand very early and rapid for this time of year.

[bobcobb]

ColoradoBob,
While that may be true for the long-term average, the 2016 SIE is 10 days behind 2015, which I think is a better measure of the scale of things. Either way, as Chris would say, should make for an exciting melt season.
Neven,
The extent loss was particularly pronounced in April and the first half of May, but it's slowed down considerably in the second half of May despite the high temperatures. Any ideas on why that is? Something with the winds?

[Neven]

In a Neoliberal context, DMI is heavily financed by lucrative advertisement contracts. Hence DMI is trying to attract traffic to their web site, which will be exposed to ads

Well, if the government doesn't fund them properly, they will be understaffed. The last reply I received from my contact at DMI was that they were extremely busy. I've asked - twice - what the exact reason was for discontinuing the SST anomaly graph (faulty data, switch to other satellite sensor, etc), but never received an answer.

I don't know if they are understaffed, but if they want more attention, I can provide it, as I link to DMI pages all the time. If they don't remove them during the melting season, of course.

What annoys me more, is that they left that old DMI 30% extent graph stand for ages (even after the new one took over), until climate risk deniers caused such a shitstorm they had to explain and grovel. But if I ask them to put back an excellent and useful SST anomaly map: nothing.

It's like school where the bad pupils get all the teacher's attention, and the rest is neglected. ;-)

[Neven]

Hi Bob,

The extent loss was particularly pronounced in April and the first half of May, but it's slowed down considerably in the second half of May despite the high temperatures. Any ideas on why that is? Something with the winds?

From the post above: "High pressure has continued to dominate the Arctic, though the anti-cyclones aren't as strong and big as a few weeks ago when they spectacularly pulled the ice away from the North American coasts."

So, yes, something with the winds. Nevertheless, the daily average drop for May (JAXA, up to the 27th), is 61K, and for the last 10 days it's 51K, which is still higher than the daily average of half of the years in the past decade. I don't know about slowed down considerably.

Of course, if you're 500K to 1 million km2 in front of other years, it probably means they have some more easy ice to burn, and you slow down as soon as conditions shift.

But more important than extent decrease right now is the build-up of melting momentum (I think). Unfortunately, that's difficult to assess, but I believe that 2016 so far isn't doing below average in that segment either.

What's going to happen after the next 3-4 days is going to be very important, but the forecast isn't entirely clear.

[Sam]

Neven,

One of the huge changes this year shows up off the north coast of Ellesmere. When I first started watching the ice in the mid 1990s, that ice was almost completely locked to the land. By 2007 that all changed. Somewhere in there (I forget when, though it was just a blink ago it seems like an eternity since) the ice separated from the land and an annual lake with a unique ecosystem that was thousands of years old drained and was lost forever.

By 2012, movement of the ice off the land in the late season was routine.

Last year, the ice broke completely free about July 4.

This year, the ice shattered and splintered beginning at the first of May. By mid-May the ice was free.

Now the ice is being dragged around like a worn out old rag doll with its stuffings coming out all over the place. In 2015 that began to happen in early July.

We are fully two and a half months ahead of last year in those terms. The 'thick' ice, what there is left of it, is being rapidly transported toward the ice grinder that the Beaufort has become. Over the next four days two storm high pressure systems (on the Canadian and Siberian sides) are predicted to move over the arctic. At the same time, conditions are set up for strong surface air flows pushing across the arctic toward Svalbard coupled with a strong offshore flow from Ellesmere.

The next week should be spectacular. Rather than setting in for thicker ice to slow things down, it appears that instead the thicker ice will be pushed/pulled into the warmer Beaufort to be ground to slush.

It appears that we are still on course for 2.0-2.5 million square km by seasons end as the most likely result, with less than 3 being highly probably and less than 1 though possible, unlikely.

Sam

[Sam]

For anyone who wants to see this in action, open Worldview off the north coast of Ellesmere beginning at the end of June and step forward to today. Using arrow keys you can do it as a little movie. I don't have the tools to create that or to do it as a gif, or I would.

http://go.nasa.gov/1X8PqX3

Sam

[Sam]

Correction - Late April - of course. Late June was last year. Go back a year and do the same, but move to late June to see a similar though less spectacular movement.

Sam

[Jim Hunt]

Don't forget to check out late May 2014 too. See also:

http://forum.arctic-sea-ice.net/index.php/topic,1493.msg78548.html#msg78548

et seq.

[Neven]

It appears that we are still on course for 2.0-2.5 million square km by seasons end as the most likely result, with less than 3 being highly probably and less than 1 though possible, unlikely.

The fact that is possible, is interesting/exciting/worrying/frightening in itself, but the Arctic is very unpredictable. Anything can happen (except perhaps for the trend to return to pre-2007 levels any time soon).

Right now, just like you, I focus on the forecast for the next 7 days, watch for that last sliver of ice attached to the North American coast to get out of the way, whether Franz Josef Land will also be circumnavigable (Svalbard already is, something only seen before in 2006, around this date), and, of course, melting momentum.

[iceBunny]

@P-maker:

If you go to this site: http://ocean.dmi.dk/satellite/index.uk.php and choose ‘Two days before Tomorrow’ (i.e. yesterday), you will get something like an observation-based SST anomaly map for the Arctic...

Unfortunately not.

DMI has unfortunately decided to extend their anomaly scale to the extremes of -50 deg C and + 20 deg C

It's the same scale as the SST maps and that's because SST maps are shown instead of anomaly maps. In fact the anomaly map is the SST for the day after the given date.

http://ocean.dmi.dk/satellite/plots/satsst.arc.d-04.png

http://ocean.dmi.dk/satellite/plots/satanom.arc.d-05.png

[Jeff Kuper]

Test, test, test. Please disregard if this actually posts. Lurker here and I've had a problem posting here previously and so just testing to see if I can post here. Appreciate the knowledge base here and while I don't have much to contribute would love to ask questions to be able to better my understanding because I believe this to be fairly important and more people should understand what is going on in the arctic.

(Really awesome run on sentence there but I'm good with that)

[John Bilsky]

Neven,

I do believe you can stop watching for that last sliver of ice attached to the North American Coast to get out of the way. By the looks of things, that has happened or is so close that it will by the last hours of May.

And FWIW, I don't see wind or heat or any other factor being MOST important or the definitive driver of ice loss. What is happening now is the quintessential definition of "cooperation".
It appears that they ALL are playing a pivotal role. Very difficult to model for sure.

[John Christensen]

Update on the DMI SST model:

DMI is transitioning to a new supercomputer (Which is being installed in Iceland, powered by geothermal energy), which is temporarily causing some of the older models to malfunction.

They are working on this and will get all models working on the new supercomputer.

[fryingpan136]

Here is the latest NASA Worldview of the sliver:

http://go.nasa.gov/1Ufs8b7

[Colorado Bob]

The Media Is Ignoring The Most Important Part Of Stephen Hawking’s Comments On Trump

But here’s the thing: in that same interview, Hawking also said he didn’t believe Trump was the greatest threat facing America, or even the world. The greatest threat, he said, is human-caused climate change.

“A more immediate danger is runaway climate change,” Hawking said. “A rise in ocean temperature would melt the ice-caps, and cause a release of large amounts of carbon dioxide from the ocean floor. Both effects could make our climate like that of Venus, with a temperature of 250 degrees.”

Link

[Bill H]

I'm trying to track down data on sea ice extent and area. It seems to be in very short supply. The JAXA web site seems to be down, as does the NASA "NEPTUNE" page, which give week by week updates on both extent and . Along with the problems with satellites monitoring sea ice it's a strange confluence of events: if I were a science denier I would be yelling: "CONSPIRACY".

[Jim Hunt]

Bill - See:

http://forum.arctic-sea-ice.net/index.php/topic,230.msg78506.html#msg78506

et seq.

[Rob Dekker]

Hawking said :

Both effects could make our climate like that of Venus, with a temperature of 250 degrees.

You have to respect everyone's opinion, but Hawking is way off with the facts here.
Venus' atmosphere is 96.5% CO2, at 93 bar.
Earth's atmosphere has 0.04 % CO2, at 1 bar.
Our oceans will boil off way before we get to Venus' atmosphere.
There is no need for such extrapolations.
What we are heading into is concerning enough.

[NeilT]

Bill,

I've noticed over the years that interesting seasons tend to have instrument breakdowns.

Whilst it is irritating as hell and happens more often on "interesting" years than boring years (or is it just that we miss it more?), I wouldn't make the assumption that it's deliberate..

There is more than enough info for the casual watcher, but the lack of detailed graph data is a real pain....

There was a lot of talk at ESOC, when I arrived there, that the Airane5 and Cluster might have been interfered with. In the end it turned out to be a case of poor testing discipline. Not something ESA seem to have learned very well from when I spoke to the team manager who deployed Huygens....

[Chris Reynolds]

Neil,

I think we just notice it. I'm really missing not being able to baseline all my sea ice data on the same average period as my atmospheric data.

It would have helped if, in anticipation of failures, NSIDC had have had the resources to run a shadow data stream of F16 and F18 along with the F17 data so they could rapidly and seamlessly transition in the event of failure of any one of the systems.

[wayne]

Stephen Hawking was thinking on a geologic time scale, disregarding our common measure of time, in the very distant future, runaway Greenhouse gases are possible. His world is sized as wide as the universe, where space time is usually judged in parsecs not kilometers.

[Kevin O'Neill]

Regarding a runaway greenhouse vis a vis Venus: As Wayne said, Hawking was likely talking of geological timescales - and even at those timescales we're not talking 10s or 100s of thousands of years - but hundreds of millions. As Hansen has explained:

"Earth can "achieve" Venus-like conditions, in the sense of ~90 bar surface pressure, only after first getting rid of its ocean via escape of hydrogen to space. This is conceivable if the atmosphere warms enough that the troposphere expands into the present stratosphere, thus eliminating the tropopause (see Fig. 7 in our paper [Climate sensitivity, sea level, and atmospheric CO2], causing water vapor to be transported more rapidly to the upper atmosphere, where it can be dissociated and the hydrogen can then escape to space. Thus extreme warming of the lower atmosphere with elimination of the cold-trap tropopause seems to be the essential physical process required for transition from Earth-like to Venus-like conditions.

If Earth's lower atmosphere did warm enough to accelerate escape of hydrogen it would still take at least hundreds of millions of years for the ocean to be lost to space. Additional time would be needed for massive amounts of CO2 to accumulate in the atmosphere from volcanoes associated with plate tectonics and convection in Earth's mantle. So Venus-like conditions in the sense of 90 bar surface pressure and surface temperature of several hundred degrees are only plausible on billion-year time scales."

The earth would be uninhabitable for humans long before then, but these are strictly hypothetical worst-case scenarios and it's really unknown if there's even enough fuel to 'achieve' it.

[Rob Dekker]

Thanks wayne, Kevin,
Hansen said :

Venus-like conditions in the sense of 90 bar surface pressure and surface temperature of several hundred degrees are only plausible on billion-year time scales

That statement by Hanse puts Hawking's statement about climate change into much needed perspective.
I'm kind of glad the press did not pick up on that, and instead focused on what Hawking had to say about Drumpf. Which was spot-on.
But we are digressing.

[AbbottisGone]

In for a penny in for a pound: if Hawking was wrong about a Venus like Earth in realistic terms then so he also might be- in all probability- about Trump.

America is an economy... if economics has become global then that is the context into which his voice for leadership aspirations is being put forth!

Same as it ever-was, mind you, of course!

[navegante]

And ... to veer away from this, weather forecast (day-scale) is becoming very complex. Not the worst that ice has seen in decadal scale, but lots of warmth being advected over the main pack and over CAA, with a spread of large ice extents toward the Atlantic sea (still full of water, volume increasing, afraid so)

[navegante]

Atlantic Ocean :) Still big

[Sarat]

A bit off topic, getting back to the discussion of Alaskan coast being ice free early in the season. Since last Naven mentioned it it looked like the high pressure in the gyre was about to tear it open. Now in the past few days or so the winds have been somewhat unfavorable nudging the ice towards the coast, interestingly this does not seem shrink the existing gap suggesting that the heat in the open water is sufficient to melt out the encroaching floes.

[NeilT]

Hindsight is a wonderful thing Chris and the usual calculation is probability * criticality of the data stream to customers.

In this case the probability was low (but still a real threat) but the criticality of the data stream was even lower.

Regardless of what we think.

The good thing with computing though, usually, is that any work they have to do to get this back online can be re-used in the event of a future instrument failure.

Not much consolation today but there we are.

[navegante]

Sarat, given the state of the Beaufort sea ice, it is equally bad that (warm) wind blows from the continent or (cold) wind blows from North; as you say, for the second case the ice is drifted toward the coasts and onto the open waters that have been absorbing heat for one month.
The only weather that can preserve it is the sustained absence of wind and lots of fog.

[Chris Reynolds]

John C,

Sorry I forgot to reply to your post of 30 May.

Yes, sometimes I am a bit vague in my phrasing. But here is the graph of Beaufort Gice thickness volumes as posted above.

https://4.bp.blogspot.com/-mJRdFEQY3ug/Vyo0B4PKyVI/AAAAAAAAC7k/azEYCby_cZkFDGAwnEU7pxZO9idfgM98gCKgB/s1600/GICE%2BBeaufort%2Btimeseries.png

If we take 1995 as the start of the decline, a decision that seems reasonable in terms of Lindsay & Zhang and the running sum of interannual differences of September extent:
http://farm3.staticflickr.com/2890/13293791045_5ce2e28c53_o.png

Then we could look at pre-1995 as suggestive of the 'healthy' Beaufort.

Going back to the Gice plot, first link in this post. It seems that years with low presence of very thick ice were the minority with years of high presence of very thick ice being the majority.

Since 1995 years of very little multi year ice have become much more prevalent. I think the reason is a combination of summer open water formation (ice melting out) and less MYI to export from the Central Arctic.

[Chris Reynolds]

Neil,

I don't think it's just hindsight, we have ample precedent of satellite failure and not only in sea ice. I am aware that the operation is being done on tight budgets and setting up a shadow data stream takes time (time = money).

But in my lab I have a set of kit that rarely gets used but is annually calibrated. I've just been using one such item today...

We sent our main IR calibrator off for annual calibration. Somewhere in transit or at the other end, the infra-red emission plate has been severely damaged. Then whilst the wrangling over who is responsible for the damage was ongoing our secondary calibrator failed. How's that for low probability?

So today I've been covering for the chap in the temperature lab (who is off on leave - how's that for probability?). And I have been using a mothballed dry well calibrator with it's block removed and the 'well' within which temperature is generated acting as an infra-red source. It's designed for such useage - that's why it's kept in working order.

We have redundancy upon redundancy because whatever the ultimate causal pathways, Murphy's Law / Sod's Law is real in engineering. i.e. If it can go wrong it will, and when it goes wrong it will be at the most inconvenient moment.

[Herfried]

Stephen Hawking is a shining bright light in science. Maybe the most intelligent man these days. But even he can fail to do his homework - to collect enough data.

So... imagine a world, where every bit of fossile carbon indeed was burned. And the oceans warmed up, released the sea-bed methane.

Sounds decently bad.
But a world like that, a carbon dioxide level of 1000 - 2000 ppm and an additional methane burst happened. And the thrilling thing is: It happened a time, when the world was not that different from our modern one. The sun had already our present power, the continents were lying at almost the right places, just India did not yet collide with Asia, and the Mediterranean sea was bigger. In the early Eocene this lead to the PETM (Paleocene Eeozene Temperature Maximum. Tropical polar sea coast with saltwater crocodiles (fossils...). There were no glaciers anywere in the world, even not in the densly forested antarctic mountains. There was an anoxic deep sea, and a subsequent deep sea life extinction event. But the climate then was stable. So it would be now. Indeed, this carbon boost was rapidely washed out of the athmosphere. A hot greenhus world means less radiation from the surface into space and more convection. Also the few changes to today made the eocene earth moist. The world was wet (and so it would be again).

A wet and hot world is washing whole mountains into the sea in really short time. Many minerals are abundant which bind CO2 during this withering and sedimentation processes.

During the Eocene the active volcanism of 100 Ma before was subsiding significantly. So the constant source of CO2. And in contrary the CO2 - binding withering thrieved. Addidionally significant amount of biological carbon was bound in deep sea sediments (hello crude oil).

And this is now minus 250 years, continents drier (geology changes), CO2 sequestered by withering, a cold ice age climate in a short warmer intermediate phase.

Today we are changing it. No volcanism, but humans. We are doing it way faster, what took dozens of Ma in former times, we are doing it in a few hundrets of years.

We may walk directly into a modern PETM. Oh and this would change a lot 120m + sea level. completely tropical earth, no cold-loving ecosystem survives. But then the carbon is over, the withering dominates again. It may take a few Ma - but this geolocigal cycle is on cold now (and this lasts 100 - 200 Ma, when you look back to older events). Our CO2 will form sediments, and the earth will cool down to at least near ice age conditions again.

What do you need for Venus? More solar power. A lot more. Right now - if CO2 ever fell below 100 ppm due to withering we would see a snowball earth again. We are way closer to a very cold earth than to a runaway greenhouse climate.

Right now, the greenhause effect of water amplifies any change of conditions, but not to a runaway risk.

With (a lot) more solar power this may change once. Despite clouds, water vapor is a strong greenhous gas, with more solar input an atmosphere of water vapor would be stable - and than this heat would crack the carbonates and add CO2. Likely we will not go completely venus in far, far future, we do not have enough carbonates to support a 90 bar atmosphere, it is (and was at the first days of earth) more a "Venus light" with some 20 bars or so (if I remember a paper right I read).

[A-Team]

The thing that strikes me is here we are, the 2nd of June only 2016 and no one in the scientific community has the slightest physical basis for issuing reassurances that this melt season won't end badly.

Very badly.

Without any need to invoke improbable weather patterns or rare storm events. Just unfortunate but unremarkable combinations of business as usual. Conditions we have seen in numerous times in recent years.

This is no way to manage a planet.

Sure, we might slide by another year or two but the downside risk even for one year is colossally disproportionate. The burden of proof is not on us to prove this Sept will be a fiasco but on policy setters to prove the next twenty won't. That's the essence of the precautionary principle.

[Rob Dekker]

Very well spoken, A-team. Thank you.

As far as our scientists are concerned, I think they are just like us right now : Watching with our lower jaw on the floor, as melting season 2016 unfolds.

[John Christensen]

Given the AO index forecast moving to a neutral state, the cold in northern Greenland and also reasonable temperatures in northern Alaska and much of western/central Siberia, there seems to be a 50/50 chance of the 2012 extent dropping below the extent of this year within the next two weeks.

The biggest unknown I see is the excessive heat in eastern Siberia, which cannot avoid wrecking havoc to adjacent sea ice in Chuckchi, Bering, and more importantly the ESS.

[D]

The ECMWF & GFS forecasts for a series of lows over the Arctic ocean will slow the conveyor belt exporting ice but the Canadian and Siberian sides of the Arctic will get hot. Ice melt in Hudson's bay and the Labrador sea will keep ice extent dropping for the next few weeks. The Kara sea is also going to continue to melt out. We'll soon see how thick this ice is on the Siberian side.

I expect extent to be close to 2012 levels in 2 weeks.

[Ben Burch]

Animation? The small NSIDC ice concentration image near the top of this item is not an animation and does not link to one...

[Neven]

Animation? The small NSIDC ice concentration image near the top of this item is not an animation and does not link to one...

It is a bit static, isn't it? ;-)

I'm making a new map for each new update, and then add it to the animation (see for instance last year). But as this is the first update, there's only one image. Things will move in ASI update 2, I promise.

[Ben Burch]

Thanks! Have you noticed the interesting excursion the Antarctic freeze-up is taking?

[Neven]

Thanks! Have you noticed the interesting excursion the Antarctic freeze-up is taking?

No, not really. I saw that the rate of increase slowed down on the UB SIE map that's on the ASIG Daily Graphs page, but as I know very little about Antarctic sea ice, I don't know what to make of it. I occasionally would check out the images of Antarctic sea ice on the Cryosphere Today website, but things are still a mess there because of the F17 SSMIS sensor issues.

[Ben Burch]

Trending low past 1 std dev almost to 2.

[Kris]

Short a notice, the
1st of the month Arctic Parade
has been updated, images now come with a much higher resolution making it more comfortable to compare.

Well, hoping this will be visible to anyone ...