During the melting season I'm writing (bi-)weekly updates on the current situation with regards to Arctic sea ice (ASI). Because of the demise of AMSR-E the IJIS sea ice extent (SIE) numbers are no longer central to these updates. Instead I now use Cryosphere Today sea ice area (SIA) numbers and compare them to the SIA numbers in the 2005-2011 period. NSIDC has a good explanation of sea ice extent and area in their FAQ. I also look at other things like regional sea ice area, sea ice extent, temperature and weather forecasts, anything that can be of particular interest. Check out the Arctic sea ice graphs webpage for daily updated graphs, maps and live webcam images.
April 22nd 2012
A new year, a new spring, a new melting season. After a very deceptive/instructive end of the winter season the Arctic sea ice is off to an extremely slow start. Of course there already were above average conditions in regions like the Bering Sea and Baffin Bay, and when two weeks ago a big high pressure system in the middle of the Arctic got a huge clockwise gyre going,the ice pack was pushed into the big, empty expanse on the Atlantic side of the Arctic (see Novaya Zemlya April 2012). But because temperatures are still quite low at this time of the year, the ice pushed southwards didn't melt and the leads that were created elsewhere quickly froze over.
Conditions have turned this year into a copy of 2010, worse even, with extent and area numbers approaching the long-term averages. Whether the situation remains like this, or whether trend lines start falling of a cliff like they did in 2010, is the first big question of the melting season.
Without further ado, let's have a look at the numbers.
Sea Ice Area (SIA)
Here's the current SIA graph based on CT data:
The 2012 trend line is clearly jutting out. SIA had been going down very hard in the first week of April, but since then we have seen a substantial slowdown, with lots of days of SIA increase. The numbers make it more than clear that 2012 is behind all the other years in the 2005-2012 period, and thus 8th out of 8 years.
The current difference between 2012 and the other years is as follows:
- 2005: +472K (-31,277)
- 2006: +488K (-37,327)
- 2007: +903K (-30,747)
- 2008: +699K (-41,979)
- 2009: +121K (-37,793)
- 2010: +236K (-48,659)
- 2011: +416K (-44,019)
Between brackets is the average daily area decrease for the month of April. 2012's average daily area decrease for April is currently -33,816 square kilometers.
On the Cryosphere Today SIA anomaly graph we clearly see how close 2012 is brushing against the long-term average:
The regional SIA graphs confirm the reasons for the total SIA number being so high. The Arctic Basin, Kara Sea and Greenland Sea saw a late extra increase, whereas especially the Bering Sea is still anomalously high.
Sea Level Pressure (SLP)
During the melting season and the freezing season looking at weather maps and forecasts can be a big help in determining what is going on up north. However, it becomes a tad more difficult in the transition periods between the two seasons. Winds blowing the ice away somewhere that leave an open patch of sea water during the melting season can still get frozen over in the transition period. But that doesn't mean we can't have a look to see if we can make sense of what has happened and will happen in the short-term.
So here's an animation of SLP images from the DMI Centre for Ocean and Ice of the past three weeks. DMI has improved these SLP images by showing the isobars over land as well, which is very helpful:
This underscores my point: that huge high pressure system over the central Arctic would have caused substantial decreases in summer, but in the current transition period it actually slowed down SIA/SIE decrease.
So even though it doesn't tell us much, I've made this animation of the ECMWF forecast for the coming 5 days (click for a larger version):
There's a low moving near the Bering Sea, which will push the ice southwards, but as we have been seeing in the past couple of days on the Uni Bremen sea ice concentration maps the patches of open water aren't freezing up as fast as they did this past winter. A low near Baffin Bay should start compacting the ice there, and I'm not sure what the effect of the high forming over the Kara Sea will be. But all in all I would expect a faster decrease than witnessed in the past 10 days.
Update conclusion
This year the melting season will be covered for the third time on the Arctic Sea Ice blog. I hope everyone will enjoy watching, analyzing, forecasting and speculating together, and frankly, I don't see how we won't.
PS These (bi-)weekly updates of course take over the function of the winter open threads.
Excellent post, Neven, and I agree completely with your assessment of the current situation.
CT SIA dropped below the 13 million km2 mark yesterday, day 112. That was the latest it's done so since 2001 (day 121). More interestingly, that's two days later than the 1979-2011 average of day 110, and a full 22 days later than the 2005-2011 average of day 90.
(2011 saw the 13 million km2 mark crossed earlier than ever before, on day 71. However, it took another 46 days to drop below 12 million km2, the longest ever, and more than twice as long as the 1979-2010 average of 22 days.)
Looking at forecasts and reading what others here have written, my guess--and, given my utter lack of success in the "Guess The Maximum Extent" poll, you should probably just ignore me--is that dropping below 12 million km2 will take about two weeks (and, to stick my neck out even farther, 11 million will only take another two weeks after that).
Posted by: Jim Pettit | April 22, 2012 at 22:47
That's the spirit, Jim! :-B
I personally believe we will see a 2010-type drop with 2012 joining the pack of trend lines quite soon. What happens after that, is up for grabs.
Posted by: Neven | April 22, 2012 at 23:17
Neven,
Isn't it time to setup the poll for the CT minimum daily sea ice area?
Posted by: fredt34 | April 23, 2012 at 15:00
CT SIA anomaly reaches 2nd highest daily value in over 7 years at -.08 m Km^2.
(Despite predictions of big drops on this blog?) .08 seems well within possibility unless these big drops start happening soon.
Posted by: crandles | April 23, 2012 at 15:06
I'm in agreement with crandles: Bering and Okhotsk are seeing controlled melting, but the strong low temperatures in northern Canada (http://www.wunderground.com/global/Region/CN/st.html) seem to keep any significant melting away from Hudson and Baffin in the next 3-4 days, where some melting would be normal by now. Alaska has also cooled, but in Barents (for what is left) temperatures have gone up, so should increase melting near the coast.
The ice cubes in St. Lawrence don't seem to melt for some reason..
Posted by: John Christensen | April 23, 2012 at 15:25
John Christensen,
As can be seen at http://ice-glaces.ec.gc.ca/app/WsvPrdCanQry.cfm?CanID=11091&Lang=eng , there is no ice left in St. Lawrence (river or gulf) except in the extreme northeast where some ice has entered through the Strait of Belle Isle. What you are seeing is an artefact of the satellite data processing that tends to show spurious ice along coastlines, and in narrow waterways, etc.
Posted by: Nightvid Cole | April 23, 2012 at 16:50
Fred, I think it's a bit too early now. Forecasting the minimum is a lottery, but after a couple of more weeks into the melting season, we can get a first feeling for the melting season. I'm planning to do a first poll around the time SEARCH issues its first request for forecasts. So probably somewhere in May.
(Despite predictions of big drops on this blog?) .08 seems well within possibility unless these big drops start happening soon.
Indeed, the CT SIA (and global) anomaly is amazing. I really wonder how much longer it's going to take. But like I said in this first update: things that make for large daily decreases during the melting season, do not seem to apply in this transition phase.
But if it keeps going this slow, the word 'recovery' will start to rear its head. And rightly so.
---
BTW, I'm going to try and do a live blog tomorrow covering the unveiling of the first map of the winter 2010–11 changes in Arctic sea-ice thickness measured by ESA’s CryoSat satellite. As it says on the ESA website:
Posted by: Neven | April 23, 2012 at 21:38
"Forecasting the minimum is a lottery"
Neven, to me it seems almost impossible to predict this years minimum sea-ice-extent from the current situation. There are so many variables (clouds, oceantemperature, windpatterns, snowcover) involved.
In my opinion sea-ice is like weather.
We know ice will melt, just like we know summer will come.
But predicting the minimum-extent is like predicting the average temperature in my hometown in the first week of August.
Posted by: Hans Verbeek | April 23, 2012 at 23:02
But if it keeps going this slow, the word 'recovery' will start to rear its head. And rightly so.
Hmmm - won't it only be a recovery when we see lots of thick MYI. Anything else will just be variation around a downwards trend.
Posted by: Account Deleted | April 23, 2012 at 23:16
*"Anything else"* ?
I would settle for 10 years of minimum area being between 3 and 4 m km^2 being enough to say that the downward trend appears to have stopped after 2007.
Not that I think that likely, but staying put seems an alternative to recovery or continued downward trend.
"Rightly so" ?
Well if it keeps going this way for 5 to 10 years then it may become possible to talk about 'rightly so'. For periods up to 2008-2012 it is going to take something really weird to make it anything other than natural variation.
Posted by: crandles | April 23, 2012 at 23:37
Well, since my qualitative comparison three days ago, my feeling on the advance of the season is this: on the one hand, I would be comforted if a prolonged FYI seasonality would linger and a ‘rubber-band’, or hysteresis, or ‘buffer-state’ would prevent things from getting real bad during my life-time. I would love to remain experiencing green springs, nature as it has always been the true spirit of my senses.
OTOH I have this dark pull toward the beauty of decay, doom, that could be the only wake-up call for humanity against a dumb self-oblivion (which would be a material oblivion, because the final release of ‘self’ shouldn’t be that hard).
In that state of mind, I found Don Perovich’ abstract
(http://www.agu.org/pubs/crossref/2012/2012GL051432.shtml )
to be adequate for day 114. Today’s high SIE could be well fitting the transition to a seasonal ice pack through the Arctic. MYI set to perish, welcome thin, seasonal, high and late SIE!
Posted by: Werther | April 24, 2012 at 00:31
I would be comforted if a prolonged FYI seasonality would linger and a ‘rubber-band’, or hysteresis, or ‘buffer-state’ would prevent things from getting real bad during my life-time.
While a buffer-state or a relatively static SIA minimum of between 3-4 million km^2 might seem like an attractive alternative - I worry that it will lull people into a false sense of security and give us more reason to do nothing about CC in our life-time.
Posted by: Account Deleted | April 24, 2012 at 01:06
Crandles
For periods up to 2008-2012 it is going to take something really weird to make it anything other than natural variation.
What do you mean by this ?
Posted by: Phil263 | April 24, 2012 at 02:01
Just found this interesting paper by Tietsche et al (2011) in your "paer" section : "Recovery mechanisms of Arctic Summer Sea ice ".
On page 1 they say :
"Our results suggest that anomalous loss of Arctic sea ice during a single summer is reversible, as the ice–albedo feedback
is alleviated by large!scale recovery mechanisms. Hence,hysteretic threshold behavior (or a “tipping point”) is
unlikely to occur during the decline of Arctic summer sea ice cover in the 21st century."
And this on Page 4:
In our perturbation experiments, we observe how different feedbacks in the Arctic compete to enhance or dampen a strong negative anomaly in sea ice, equivalent to a
strong positive anomaly in oceanic heat content. In summer, the oceanic heat anomaly is enhanced by the ice–albedo
feedback, but in winter the excess oceanic heat is lost to the atmosphere due to a lack of insulating sea!ice cover. This
leads to an anomalously warm atmosphere, which in turn causes increased heat loss by longwave radiation at the top of the atmosphere and decreased heat gain by atmospheric advection from lower latitudes. A lasting impact of the ice– albedo feedback is not possible because the large!scale heat fluxes quickly adapt to release the excess oceanic heat from the Arctic.
Hence, we find that even dramatic perturbations of summer sea!ice cover in the Arctic are reversible on very short time scales of typically two years. This suggests that a so called tipping point, which would describe the sudden irreversible loss of Arctic summer sea ice during warming conditions, is unlikely to exist.
May be we might be seeing one of this short term recovery phase in 2012?
Posted by: Phil263 | April 24, 2012 at 02:24
I have a question.
If the Bering Strait (BS) remains iced up longer than usual does that have an impact on how the melt/export season develops? I don't hear anything about ice being exported thru' the BS but does it have any effect on how ice is transported around the basin?
Posted by: Pete Williamson | April 24, 2012 at 04:10
Sorry another question.
I see "natural variation" talked about a lot in climate blogs and I was wondering what people think that means in respect to arctic sea ice. Are we just talking about seasonal/annual variations that might move metrics away from a long term trajectory for a year or so, things like AO. Or are there 'regime changes' or dare I say 'oscillations' that may alter the rate of change (or even the sign) for a decade or more? I can imagine internal changes promoting 'regime changes' but I'm curious if people consider an external processes that might work on these time scales?
Posted by: Pete Williamson | April 24, 2012 at 04:30
Phil263. Yes, it's interesting but I'm a bit reluctant to go any further than that.
The thing that strikes me, and I am totally and entirely lacking the competence to look into it further myself, is the ocean heat transport anomalies. They seem to stay with the current 4 to 7 wm2 figures, and see what happens when their imposed perturbation of the Arctic system itself responds to it. They seem not to have used any modelling about expected changes in the oceans.
So if the oceans feeding into the Arctic heat further? Which is what I at least am expecting, does their whole schema collapse or will someone else rework it on revised numbers?
Or is my incompetence leading me astray here.
Posted by: adelady | April 24, 2012 at 08:03
The Sea Ice is going to drop below 5 million kilometers squared. The pattern is the culprit of this because it set up perfectly to cause huge Bering Sea Ice anomalies. In a more even year, the Kara and Barents would be the same but with thicker ice and the Bering would be lower.
The ice is very thin. There is almost no MYI and there is a whole lot of new thin ice along the Russian sea shore lines.
This season is about to kick off with a bang in the next 7 days.
The Bering saw huge loses today. That won't continue at that pace but it will melt. The SOO is going to keep melting faster with continued heat coming in.
By tomorrow an SLP moves along the Eastern Hudson Bay. Warmer temps and southerly and Easterly winds pick up in the Baffin Bay.
At the same time an SLP is forming over SE Russia Pacific ocean which will enhance a southerly flow around an elongated area of SLP. In the Kara an HP elongates across the entire arctic. This will pick up winds from the South and warm things up, it also coupled with an SLP in the Eastern arctic will push the ice in that region which is thin back towards the pole.
By day 2-3, the baffin has warm southerly winds pumping in. The Kara and Barents have southerly winds, the Fram has a strong northerly wind. very strong, so ice is going to fly out the fram as well.
The SOO is being full baked. The bering has a down sloping warm flow off Alaska and a weak southerly flow.
after that the pattern starts to go into flux but is favorable for big drops.
It also warms up overall a lot along the frindges. The Kara Might clear out a lot of ice if this pans out. Maybe a couple hundred thousand.
Posted by: Chris Biscan | April 24, 2012 at 08:34
Phil263 & Adelady,
Also have a look at http://geosci.uchicago.edu/~abbot/PAPERS/abbot-et-al-11b.pdf
On page 8 when discussing the work of Tietsche et al (2011) and other studies - they make the point
These results indicate thatmany GCMs do not show strong signs of bifurcation behavior as summer sea ice is lost, although some appear to.
and
More generally, determination of whether bifurcations in summer sea ice occur in GCMs may be difficult,
given large climate noise and the potential that GCMs are being forced nonquasistatically
Which seems to a non-climate modeller that it is all a bit unclear at the moment.
Posted by: Account Deleted | April 24, 2012 at 08:39
Phil,
I was responding to Neven's "But if it keeps going this slow, the word 'recovery' will start to rear its head. And rightly so."
I mean:
Almost* anything that happens this year won't be recovery in the sense of reversing or stopping the trend, it will be natural variability about the downward trend (as Colin put it). It will take several years of data before we could say the trend has stopped or reversed. 2008 to 2012 is not long enough (especially when we have declining volume from 2008 to 2011).
2012 may turn out be 'a bit of a recovery this year' but the trend would still be downward. There is a difference between a 'recovery' which I am taking to mean something rather sustained rather than a bump on a downward trend.
The word recovery may well be used but I doubt it will be 'rightly so'.
There seemed a huge difference between Neven and Colin posts, a large area between seemed worth pointing out as it seemed to me to make both posts seem extreme to the point of being wrong.
*
If you were asking about the something weird, then suppose a huge volcanic eruption caused ice to only to decline in area by a further 1m Km^2 this summer. Clearly this wouldn't be natural variation about the downward trend but a reaction to the forcing. (This is only pedantic nit-picking Colin's post. The slightly bigger point was there could be stabilisation of ice levels or slow recovery of area, extent and volume over a number of years without any increase in thick MYI. So a couple of nit-picks but largely agreeing with Colin against Neven's 'rightly so'.)
Posted by: crandles | April 24, 2012 at 12:10
Crandles
Thank for your clarification. Totally in agreement with you when you say ' 2008-2012' is not long enough. I also concur about the fact is still probably downwards even though we might see a bit of an uptick this year...
Posted by: Phil263 | April 24, 2012 at 13:03
Adelady & Colin
I posted about the Tietsche paper as I vaguely remember something about it. I do not pretend to fully understand its content, however the general gist makes sense. Too often, we tend to emphasise positive feedbacks and forget about the possible negative feedback loops. Systems always behave in very unexpected ways: human social systems and nature alike.
Posted by: Phil263 | April 24, 2012 at 13:08
IIRC, Tietsche et al is in play in a world with CO2 forcings set to zero at initialization and a climate at equilibria. So, very unlike today's conditions. It does, however, speak to the "memory" of the ice.
The models that do take into account more of the real-world mechanisms taking place in the Arctic do show a bifurcation. They just disagree on the timing.
Posted by: Daniel Bailey | April 24, 2012 at 14:15
>"IIRC, Tietsche et al is in play in a world with CO2 forcings set to zero at initialization and a climate at equilibria."
AIUI They did the ice removal at several different dates/GHG forcing levels during a transient simulation. Each time ice returned to the trend within about 2 years. So at initialization the climate was no more at equilibrium than todays climate but it seems that ice levels in any transient climate are unlikely to be as far behind the equilibrium level as 2 years.
(Maybe you are thinking of the earlier Connolley paper which did only do it under preindustrial conditions.)
Posted by: crandles | April 24, 2012 at 14:46
just to inform the second buoy has been deployed, if someone here didn't know it already: http://obuoy.datatransport.org/monitor#buoy4/webcam
Posted by: Otto Lehikoinen | April 24, 2012 at 19:29
Thanks, Otto, it's on the webcam page.
That high over Novaya Zemlya gives us a fantastic clear view.
Posted by: Neven | April 24, 2012 at 21:07
I remember a couple of days ago when everyone was saying that huge drops will come in about a week but I made a prediction that the decline will remain close to the 1979-2000 average since most of the regions are declining in a near average rate.
Just checked the numbers today and wow, I honestly thought my prediction was doomed, but the declines DID stay close to average.
No one even said anything about my comment, and yet I was right. I just hope now everyone pays more attention into my predictions now :)
Posted by: Kalle GZ | April 25, 2012 at 00:14
http://nsidc.org/data/seaice_index/images/daily_images/N_stddev_timeseries.png
Wow extent is THAT close to the 1979-2000 average holy cow we might actually go above average for the first time since 2003! (Although I doubt it will happen.)
Posted by: Kalle GZ | April 25, 2012 at 00:18
I don't think the NSIDC or CT trend lines will go over the average trend, but I have been so incredibly wrong so far, that I wouldn't be surprised if they do.
Everyone would be Chris Biscan, Apocalypse4Real and yours truly. That was three days ago, and CT lags a bit, but I admit that I'm not seeing any huge changes yet on the Uni Bremen SIC maps.
But based on the weather forecasts (however dodgy the transition phase can be in that respect) and the fact that 2012 is so much behind all other years, years that started showing huge drops around this time (2010 comes to mind, almost 300K below 2012 at this point), that it only makes sense that we will see decrease picking up again in the coming week.
But it has been a crazy year so far. Perhaps the ice is megathick everywhere and the trend line remains close to average for a lot longer. Nothing in the Arctic is a dead certainty.
Posted by: Neven | April 25, 2012 at 00:31
Neven wrote:
You well may say so.
Surpise, surprise!
Right before the coast of Wales (AK Bering Strait) we can see a large polynia already has been formed - also a little bit deductable from the Bremen Maps.
"Normally" things like that only develop from the end of May on.
Warning: this cam and it's software are very, very resource consuming. So close everything else before you would dare to click on the link!
And it may take a while before you could see something.
The right vertical slide bar controls the elevation, the left slide bar controls the zoom, and the horizontal slide bar beneath the image controls the azimuth.
In the case your system can't cope, try this:
Wales Bering Strait cam without controls
Posted by: Kris | April 25, 2012 at 01:52
Kalle GZ,
Give it a few more days.
We have only had two observational days since then.
DMI has dropped 3 days in a row. CT lags back a couple days.
the Pattern is flipping right now to a much better pattern for ice loss.
Posted by: Chris Biscan | April 25, 2012 at 05:26
There is a lot of thin ice floes all over the Southern Baffin towards the Hudson Strait that are about to take a pounding.
Posted by: Chris Biscan | April 25, 2012 at 06:00
Arctic Sea Ice Forecast:
Day 1:
Posted Image
A broad area of High Pressure. Has formed across the central arctic from the Siberian side of the Kara Sea to North Central Canada. An a strong HP is moving North East in the NATL, while Greenland has a large 1050HP, the Nordic Seas to the UK have SLP.
An SLP over the Eastern Hudson Bay will continue to move North to NE and and bring Southerly winds into the Baffin Bay region. This will obviously cause some compaction and enhance melt there. Sea Ice Export out of the Fram will be substantially increased as a tight pressure gradient sets up. The Barents and parts of the Greenland Sea will see a strong wind set up from the south and start bringing warmer air into this area, this will take a few days to get going good. This will also compact ice in the Kara as well but will take a bit longer to get going.
The Beaufort will have a strong southerly wind bringing warmer air up there, but mostly will have more clear skies, in fact a lot of the arctic will be clear with this. The SOO continues to bake with a warm southerly wind, Ice will continue to melt out there. The Bering will see a southerly return flow and a bit of compaction.
Posted Image
By day 2, the Bering SLP deepens and moves East, so winds will primarily be East to West and will be warmer(0C+ 850s showing up in spots) but less compaction there. The SOO keeps the southerly wind and heat 5c+ 850s take over the entire SOO except shore areas. The Pacific arctic will continue to see sun but not much else.
The HP in the North Atantic Drifts East. Winds clash half way up the Baffin where the warmer southerly air with 2-5C 850s push into the ice and colder northerly wind off the pocket of -20C 850s sitting over Northern Greenland pushes south. the Fram export picks up big time with a long string of 15-20Kt winds rounding that SLP over Svaldbard that is also wrapping in warm air that is coming out of Europe into the Kara and Laptev and parts of the arctic basin. -5 to -10 850s move in a well as strong southerly winds. This will help compact ice in the Greenland Sea and pull ice off the shore of the Laptev, these will be pretty strong wind currents, so expect quite a bit of compaction.
Posted Image
Day 3 continues to show this pattern evolve. The Bering and SOO will continue to see temps warm there. Ice melt should be picking up quite a bit in the Bering by this point. The far Southern and SE part of the Ice will quickly melt out with warmer air and sun. another big SLP forms over Eastern North America and moves north towards the Baffin, this one is further East and a wider swath of warm air is moving North since the HP is so big and further East. The Baffin is still warm but slightly cooler than the previous day or so. The winds are weak out of the north until you reach the southern part of the bay, they they are south easterly. The Fram is going to buldge quickly and largely. The SLP over Svalbard moves towards the Central Arctic with a banana like HP over the Laptev/Central Arctic. this will allow warmer air to punch close to the pole but cold air will sit from the Laptev to the Northern Greenland. Winds are the more concerning part. Winds will be busting bleep. the 3rd day in a row of compacting winds on the ice by the Svalbard with winds from the Kara and barents shows them moving all the way through the NP to Northern Greenland where they turn Westward this will start moving the thick ice North of Greenland East and south. The Fram will still have ice moving south out of inertia while an SLP is blowing winds North with 2-3C+ 850s and warmer water, this should be very short lived however.
Posted Image
By day 4 things get whackier, the Soo and Bering are both still warm, ice will be melting there a bit faster as the heat builds. a strong SLP moves towards the NW Atlantic with the big HP still over the NATL, the baffin will be decently warm southern half and very cold northern half. Winds will be compacting some southern half. Greenland goes back to HP, the SPL moves East. The SLP moves West just off the N.Greenand sea, so the West to Eat Flow North of Greenland will be enhanced and hauling. THen winds will bend south out the Fram. WInds will be South to North from Russia to the Central Arctic. So ice will be pulled off the shore and compact, it's to early to tell how much or how many of the new open areas of water by the shore will stay iced over or stay water. I think the Kara exp southern side will melt out but towards the Laptev it's to early for large open water areas.
the Hudson will also see it's warmest yet so far. with very warm down sloping winds to hit the SW sides with 50F+ temps, but not much melting will take place yet, maybe some ice displacement from wind with temporarily shoreline openings.
Posted Image
Day 5 sees the Baffin have an SLP move over the southerm areas. Winds may compact some ice temps will be mild over the southern part, but cold over the Northern part. Northern Greenland will continue to see the Strong West to East winds moving the thick MYI towards the Fram. That is the 3rd day of constant 15-20kt+ winds. That will definitely help bulge the Fram. Not to metion the constant southern Greenland wind shifts. Warm temps will be pumped into the Southern Fram and help accelerate ice melt. THis will also bulge the Fram more. There will be some shrinking of ice extent over the Southern Fram. THe SOO will cool off a bit but nothing to stop the melt, the ice by day 5should be small and confined close to the SW shore. The Bering is split betwen two HPs trying to push warm air in from W and E but some cold from N will sag into the Bering Strait but this is -5C 850s so it won't do much to slow snow melt on ice, but ice should be protected still. Most of the Bering will be around 0 to 3C 850s so ice melt will be still going on there with the SE part of the ice pack likely gone. The Hudson see's a few days of warm 850s. The Kara and Greenland Sea areas will cool a bit, the Kara the most, this may help create Nilas in areas that get large open water from winds. Winds will still be pushing from the South, but weaker.
Posted by: Chris Biscan | April 25, 2012 at 11:27
Hans Verbeek:
"In my opinion sea-ice is like weather.
We know ice will melt, just like we know summer will come.
But predicting the minimum-extent is like predicting the average temperature in my hometown in the first week of August"
While it is correct that many things can happen that will either continue the current pace of melting or accelerate this, as you see on the SIA from CT or Arctic ROOS (easier overview with few years in distinctive colors), there is a strong correlation with the SIA in April and what it will look like in August/Sept:
http://arctic-roos.org/observations/satellite-data/sea-ice/ice-area-and-extent-in-arctic
2009 and 2010 were relatively close to current SIA for April and fared better than 2007, 2008, and 2011 during the summer months as well.
Posted by: John Christensen | April 25, 2012 at 17:35
Hans Verbeek:
"In my opinion sea-ice is like weather.
We know ice will melt, just like we know summer will come.
But predicting the minimum-extent is like predicting the average temperature in my hometown in the first week of August"
Isn't it a matter of the higher the average temperature during any period of the melt, the faster the ice will melt? So why aren't you arguing that predicting minimum ice extent is more like predicting average temperature from April through August?
Posted by: crandles | April 25, 2012 at 17:57
Agreed crandles and to why correlation between 'high SIA' in April and 'high SIA' in August makes sense:
Since the Arctic Ocean is highly stratified with cold water layers at the top, as long as the water is covered by ice, the cold top-water should remain somewhat intact in that state, but as soon as the ice is gone, the radiation will reach the darker water and heat it to expand melting of nearby ice.
Therefore, high SIA in spring months (caused by any incidental weather phenomena) should help slow the heating of top-water layers and thereby reduce risk of high summer melt levels, where both air and water has warmed.
This also corresponds well with 2006, where exceptionally low SIA during spring months increased the exposure of water to sun radiation, so even with a relatively high SIA summer minimum in 2006 (due to thicker ice at the time?), the scene was set for a slow freeze during the fall of 2006 - and for a much worse situation in 2007..
Posted by: John Christensen | April 25, 2012 at 18:29
I'm finally seeing some bigger differences when comparing today's and yesterday's UB SIC maps, notably in the Bering Sea. I wonder if that will show up on the SIE and SIA graphs.
Posted by: Neven | April 25, 2012 at 21:22
Arctic ROOS SIA seems to indicate unchanged overall pace of melting through 4/25, but let's see..
Posted by: John Christensen | April 25, 2012 at 21:35
While we are estimating the rate and extent of future sea ice melt, I thought a glance at the IRI global temperature forecast might be helpful. They are modeling increased to high probability of above average temperatures over Asia, Canadian Arctic, Greenland and the Russian Arctic. See:
http://portal.iri.columbia.edu/portal/server.pt?open=512&objID=944&PageID=0&cached=true&mode=2&userID=2
Posted by: Apocalypse4Real | April 26, 2012 at 03:34
John Christiansen wrote:
Since the Arctic Ocean is highly stratified with cold water layers at the top, as long as the water is covered by ice, the cold top-water should remain somewhat intact in that state, but as soon as the ice is gone, the radiation will reach the darker water and heat it to expand melting of nearby ice.
One thought that's been going through my mind recently that I may have seen mentioned in a minor way but seems fairly significant to me is the increased mixing of temperature and salinity layers due to storms, which I think would have greater impact and likely be more frequent as the ice recedes.
Last November when there was a big storm near Alaska I read the following paper, which seemed applicable then, but as I said I think could have broader significance: "Storm-driven mixing and potential impact on the Arctic Ocean" http://www.whoi.edu/fileserver.do?id=48251&pt=10&p=33752
Especially interesting is Figure 22 which shows an increasing number of anomalous stormy days over the 5 year periods from 1980 - 1999.
I think this effect could even be contributing to the increasingly early drop in the PIOMAS volume to CT area ratio graph Neven created in a separate thread, because if ice area or quality is decreasing and storms are increasing then greater mixing could bring a significant amount of nearby heat to bear on the ice volume, and do so fairly early in the season before the sun has had much time to take effect.
This is all hand waving of course, and it would be interesting to quantify it somehow, but I thought I'd throw the idea into the mix.
Thanks again to all for their contributions.
Posted by: DJ | April 26, 2012 at 05:26
DJ:
I agree, the heat capacity of the Arctic Ocean is such that it could easily melt all Arctic ice, if the stratification did not prevent that.
As crandles, I and others have commented elsewhere on this blog, there also seems to be an increase in influx of warmer water, especially via the Fram Strait, with temperatures of 4-6C, where the temperatures in that strait were earlier 2.8-4C.
Being above 4C, the water will no longer 'stay in place', but raise to mix with upper level water layers, which is probably why a Science artikel from 2011 (also referenced elsewhere) has estimated the increase in heat transfer to be as high as 40%.
That said; we are 4.5 weeks beyond equinox (equal to August 18), so the level of radiation that is not reaching the water compared to other years since 2007 is significant and should bode well for conservation of the ice - at least until some event kicks in and spreads the ice further southward in Baffin or the Greenland Sea, or unusually warm weather arrives at high latitudes around Chukchi or the other seas bordering the Arctic Basin.
Posted by: John Christensen | April 26, 2012 at 14:55
John, is it really the case that the Arctic itself is absorbing less radiation? A couple thoughts to consider on that -
1) Most areas of the actual arctic basin are below or at average, the total area/extent being close to normal was driven by SOO, Bering and Baffin.
2) Is it just me, or are high pressures dominating more this year leading to more clear, sunny days. I lack the skills to really evaluate this empirically, but eyeballing the satellite photos from last year compared to this year seems to indicate yes. So even if the albedo was higher at the surface due to more ice cover, might it not be the case that more or equivalent radiation is being absorbed due to much more reaching the surface in the first place?
3) Snow cover also appears to be down, which may have an effect on melt at the edges of the basin as the summer progresses.
I don't know how to quantify these observations, just wanted to throw them out there for discussion.
Keith
Posted by: A Facebook User | April 26, 2012 at 15:12
Keith,
I know; a model should be built to include the level of ice covered (SIA), the latitude of the area, and the cloud cover, and probably with a few other factors added as well, but since the point was around radiation reaching the water, I would exclude the snow cover, which mainly would help explain temperature and albedo effect overall.
Therefore, while the above normal areas include Bering, and to some degree Baffin and Hudson (Greenland Sea following closely), these are also some of the lowest latitude areas, which receive more radiation than the central Arctic seas, so ice cover in these relatively low-latitude areas should have a larger impact.
In addition, for Bering and Baffin, the high SIA levels could mean delayed eliminination of the ice arches that later in the spring/summer will allow more ice to escape southwards.
Posted by: John Christensen | April 26, 2012 at 15:41
>"1) Most areas of the actual arctic basin are below or at average, the total area/extent being close to normal was driven by SOO, Bering and Baffin."
Which means that before equinox these are the areas with sun angle above 15 degrees. So it was relevant back then. It is on fringes so some of the heat effect gets carried away and some gets carried in towards arctic basin.
Now almost all areas are getting a sun angle over 15 degrees for some of the time, I wonder if the central locations are more important because of that carry away some of the heat from around fringes effect.
Area up .264 on 2010 does not seem much. .9 up on 2007 seems a significant difference but there was a higher ice volume back then.
Nevertheless, have other people noticed the difference in brightness of modis images compared to last year? e.g.
http://lance-modis.eosdis.nasa.gov/imagery/subsets/?mosaic=Arctic.2012116.terra.4km
http://lance-modis.eosdis.nasa.gov/imagery/subsets/?mosaic=Arctic.2011116.terra.4km
I assume this is a big difference in snow cover as 2010 isn't as bright as 2011 but may be a little brighter than 2012.
Does this mean the ice has grown a little more due to less insulation from snow over 2011/12 winter (so PIOMAS volume is same as LY) but more radiation is now being absorbed despite the higher area being covered with ice?
Posted by: crandles | April 26, 2012 at 16:02
John Cristensen I do not think that there is any merit to making a link between current ice area and ice arches at the north ends of the Baffin and Bering seas. in both cases the ice within the sea is very fragmented and mobile so the only thing preventing the ice arch moving is the ice arch itself.
My eyes tell me that all the low latitude ice is greyer than last years ice which suggests to me that it is thinner and more transparent.
Land snow cover in Alaska looks thinner in some areas than at the same time last year.
The Baltic has far less ice than last year.
the current fairly high levels of ice in the Greenland , Kara and Barentsz seas are all attributable to ice moving out of the central Arctic not new ice forming in those areas. of course new ice has formed in the central arctic but so what? a 100,000 km^2 of thin ice filling leads isn't going to be consequential down the line and the current situation means that older ice moved to a lower latitude where it is going to melt sooner.
That huge polnya in the Bering is soon going to connect to the open sea and Bering sea extent will drop. SOO is dropping nicely and is at expected levels. we are all on track for the big melt unless we get a random local weather event to hex things
Posted by: Philiponfire | April 26, 2012 at 17:03
Philiponfire,
I agree that while the SIA is high compared to recent years, it is also more fragile due to the overall reduced thickness and volume, which has been quite drastic.
Regarding the ice arches: We have about 300,000km2 and 100,000km2 more ice in Bering and Baffin compared to last year, so the heating of sea water by radiation should be less this year, but again agree that other factors including current and air temperature/weather play in here as well.
In years before 2007 a low SIA during winter or spring would not necessarily cause a very low summer minimum SIA, but in the new reality the pace of melting can easily accelerate quite a bit as seen in 2010 where winter and early spring SIA was still relatively high, but with strong reduction in SIA during May and June.
Posted by: John Christensen | April 26, 2012 at 17:37
>Nevertheless, have other people noticed the difference in brightness of modis images compared to last year?
Yes.
>I assume this is a big difference in snow cover
Why not assume this is a difference in image processing? Either how the images are composited, or possibly the timing of the optimal flyover.
Assuming a big difference in snow cover means assuming a big difference in snow cover everywhere there is snow, since all white areas are brighter. That seems a bit of a stretch.
Posted by: FrankD | April 26, 2012 at 17:38
Crandles: I noticed the brightness differences, too. My guess was that it's a sensor issue or a difference in image processing. (Looks like the "camera exposure" was reduced - either in the "camera" or in the processing phase.) Greenland is much brighter and details are much harder to make out in 2011 images. Presumably, the actual albedo of the ice sheet there hasn't changed much from last year to this year.
Anyone with any real information on this, please chime in. If it's due to actual conditions, i.e. less snow, it will have a large impact on solar energy up there this spring/summer.
Posted by: Shortfatape | April 26, 2012 at 17:44
"Of course new ice has formed in the central arctic but so what? a 100,000 km^2 of thin ice filling leads isn't going to be consequential down the line"
And why would this not be consequential?
Since much of the older ice was pushed towards the NA side of the Arctic in Jan/Feb, a considerable degree of the ice that has been built in the Arctic Basin, Kara, and Barentz is quite new ice. So if this ice is spreading, enabling even more ice to form (area with lower extent allowing quicker build-up compared to area with high extent), this should be beneficial and allow more ice to be crushed and compacted.
So is your argument that the high SIA levels in Bering, Barentz, and Kara, are caused not by ice being transported there at a normal rate, but that this is currently happening at an unusually high rate?
Posted by: John Christensen | April 26, 2012 at 17:50
Any estimates on the thickness of the ice in this lead off Banks Island,Canada? The Lance-Modis image is 250m pixel size.
http://lance-modis.eosdis.nasa.gov/imagery/subsets/?subset=Arctic_r04c02.2012117.terra.250m&vectors=coast
Posted by: Michael Fliss | April 27, 2012 at 02:34
The high extent and area is about to take a large drop.
DMI shows a large drop today, likely around 100K, well last night.
but the story is here:
http://i174.photobucket.com/albums/w109/frivolousz21/Iceanimation.gif
Most of that was the 25th to 26th. Jaxa updates out of sync so CT won't reflect this drop till the 28th. We will see it however on DMI tonight.
Posted by: Chris Biscan | April 27, 2012 at 02:40
John Christensen "...caused not by ice being transported there at a normal rate, but that this is currently happening at an unusually high rate?"
Whether it's normal or higher movement is secondary. The problem is that there's no ice in those regions so the ice is spreading and becoming thinner in both the originating and the receiving areas.
If the ice were moving and was met by "average" ice in those regions it would be thickening by piling up _and_ that resistance would also slow the movement marginally and thereby allow some thickening, or at least retention, in the feeder regions while the sun is still low and the air is still cold.
Posted by: adelady | April 27, 2012 at 02:45
Unsurprisingly, it's being done:
Arctic System Reanalysis (ASR)
Join up on the Website if you want to participate.
Posted by: Artful Dodger | April 27, 2012 at 03:21
MODIS showing a drop of over 115,000km^2 mostly in the Bering sea.
Posted by: Philiponfire | April 27, 2012 at 08:35
Bah brain turned off I obviously meant MASIE didn't I!
lovely clear picture of the shattered ice moving through the Bering strait on MODIS today.
Beaufort sea also looks more broken up than at the same time last year.
I see nothing anywhere to suggest that the high maximum was anything other than a localised weather outlier within the downward trend. we are heading for 2007 levels at minimum.
Posted by: Philiponfire | April 27, 2012 at 09:01
UB SIC map shows another big Bering loss compared to yesterday. I think it'll soon be century break time.
Posted by: Neven | April 27, 2012 at 12:44
After a period of small down and up change DMI shows some decline, almost -240k in the past two days (4/25 and 4/26).
Posted by: L. Hamilton | April 27, 2012 at 14:38
Saw some interesting talks at the International Polar Year conference in Montreal earlier this week, including one by Mary-Louise Timmermans on how sea temperatures cause basal melting of ice. Her data indicate that apart from upwelling or turbulent areas, most of the basal melting comes from albedo warming of near-surface waters that extend under the ice, rather than from Atlantic or Pacific water layers that tend to remain deeper.
She also noted that basal melting can occur in winter as well as summer, although of course the albedo effects are less then.
Posted by: L. Hamilton | April 27, 2012 at 14:42
Highest area anomaly since late 2004:
2012.3151 -0.0471004 12.8662653 12.9133654
"-240k in the past two days" seems not a moment too soon or is there still a risk of an above average area with the next data?
Posted by: crandles | April 27, 2012 at 15:05
MASIE drop from day 115 to day 117 is over 325,000 km^2. that is a lot of ice cubes!
Posted by: Philiponfire | April 27, 2012 at 17:14
ance-modis.eosdis.nasa.gov/imagery/subsets/?project=other&subset=BeringSea.2012117.aqua.250m
and here is where half of that ice vanished from.
very pretty picture of the Bering sea full of crushed ice.
Posted by: Philiponfire | April 27, 2012 at 17:22
I personally see nothing scary about the Arctic except for the Bering Sea. In fact, Im pretty sure about 60% of the drops are coming from the Bering Sea being cut in half in a matter of days.
Everyone should be thanking the Bering Sea for the huge drops that are taking us back to what the area/extent was in recent years, otherwise we would be stuck near or even above the 1979-2000 average line.
Posted by: Kalle GZ | April 27, 2012 at 22:24
Looking at the other regions of the Arctic, aside from the Sea of Okhotsk, (which the decline rate is near to slightly above average) NONE of the regions are showing any noticable drops. In fact, the Kara and Barents Sea, the NewFoundLand Sea, and the Greenland Sea are actually showing some increases.
I just think everyone is overreating about the drops in the Bering Sea and no one is paying attention to the other regions.
Posted by: Kalle GZ | April 27, 2012 at 22:26
We could either thank the Bering Sea, or we could curse it for being so high in the first place. It is both irrelevant at this point. Interesting, but irrelevant.
Kara and Barentsz have been very low for a couple of months, although the first did recover somewhat, probably not with very thick ice. When the Greenland Sea is showing an increase, it usually means ice (some of it MYI) is transported from the central Arctic, which has implications that go beyond 'Greenland Sea has an increase in SIA'. Baffin/Newfoundland had an increase for the same reason as Bering: winds pushing ice south, leads behind it freezing over. Temps are going up, so even if winds keep blowing south (towards warmer waters and more sun), leads will not freeze over. This means that Baffin is next to go.
I disagree. No one is really overreacting at the moment. We're just watching and speculating a bit. I personally find it both intriguing and fascinating, but I think I want to watch another 4-5 weeks, before overreacting or not.
Posted by: Neven | April 27, 2012 at 22:54
Agree with Neven;
With just 47,000km2 below the '79-'08 mean SIA we are the closest to the mean since year-end 2004.
By that time CO2 was around 380 ppm and by now around 392, so forcing has increased quite a bit according to recognized climate models.
This does beg the question how it can be this high, but this is speculation and the next 4-6 weeks will show if this is ultra-thin ice that disappears quickly, or if some factors have caused the SIA to be more resilient this year.
Posted by: John Christensen | April 27, 2012 at 23:18
Speaking of arctic ice. Tamino has just done a new blog post: http://tamino.wordpress.com/2012/04/27/lets-do-the-math/
There is plot of the annual cycle amplitude, that just explode after 2005. Clearly arctic ice has change of dynamical regime. IMHO it would be wise to trough away any data before 2006.
Posted by: Yvan Dutil | April 28, 2012 at 00:03
I agree with both Neven And John, and I admit I myself was overreacting in my comment, and Im sorry about that.
I am also interested to see if we will have a 2010 May and June. If we do, I will remember next time when extent/area is near the average, it is only because of thin ice ;)
Does anyone have a link to where I could see the temperatues of the Arctic?
Posted by: Kalle GZ | April 28, 2012 at 00:33
The (linear) decline in Arctic sea ice is smallest in May and largest in September.
According to NSIDC the decline in % per 10 years (1979-2011) is:
Jan 3.3
Feb 3.0
Mar 2.7
Apr 2.6
May 2.4
Jun 3.6
Jul 6.8
Aug 9.3
Sep 12.0
Oct 6.6
Nov 4.7
Dec 3.5
So for the real interesting things, we have to wait some months.
Posted by: HenkL | April 28, 2012 at 01:18
Check this out:
Two new ITPs have been installed:
http://www.whoi.edu/page.do?pid=70997
ITP56 was deployed on a 1.5 m thick icefloe in the Transpolar Drift on April 15, 2012 at 89° 19.5 N, 1° 54.8 E
and:
ITP63 was deployed on a 1.27 m thick icefloe in the Canada Basin on April 20, 2012 at 83° 26.9 N, 115° 50.0 W
What the hell? I know they are not intentionally picking thin ice floes so the buoys can get lost?
Posted by: Chris Biscan | April 28, 2012 at 02:00
Kalle GZ asked:
That has already been posted by our FloeDevil, but to say again:
http://www.ogimet.com/gsynop.phtml.en
Pick from the left dropbox the region and check on the list at the right "Temperatures"
Posted by: Kris | April 28, 2012 at 02:13
And Kalle, if you go to the Daily Graphs page and scroll down you see a couple of graphs and maps with Arctic temps.
Posted by: Neven | April 28, 2012 at 11:13
http://i174.photobucket.com/albums/w109/frivolousz21/icecover_current-22.png?t=1335601836
Holy Smokes. Three days. That has to be around -350K to -400K.
The Baffin took a hit. But the Barents has taken a huge hit with strong winds.
they will continue today. But the drop today should be lower than the last two days where large areas of ice melted or compacted.
just like that. The CT SIA drop could be back to back 150K- days or one 200K- day. Todays SIA is the day before the two large drops.
Posted by: Chris Biscan | April 28, 2012 at 11:28
Chris is right, DMI extent goes down -400k from 4/24 to 4/27. All the loss is first-year ice, while multi-year extent actually increased -- due to its spreading, presumably.
Posted by: L. Hamilton | April 28, 2012 at 12:51
I see there is still if anything a slight negative correlation between sea ice area at the end of April and the eventual minimum in the summer over the last decade. By the end of May there is a marginally positive correlation, but nothing significant. It's not until the end of June that there starts to be any sort of significant correlation I think.
Is there a different single measure to look at for the moment that would give a better indication of the final outcome?
Posted by: Heraclitus | April 28, 2012 at 12:55
Jaxa shows compaction along the Southern area of ice in the Baffin, also the Hudson Strait is mostly water again. The area between the Kara and Laptev had a huge recession today. The SE Laptev also is losing the battle.
The Bering and SOO had a small bit of ice coagulation. But overall today was a big loss day, I'd say -75K easy.
I would expect the CT SIA anomaly to be around -300K by early next week.
Posted by: Chris Biscan | April 29, 2012 at 04:19
Chris Biscan wrote:
Be aware, everytime you're making exaggerations like that you're chopping off a piece of your credibility.
But you are a free man of course.
Posted by: Kris | April 29, 2012 at 10:24
http://i174.photobucket.com/albums/w109/frivolousz21/KaraSeaicehaulingbleep.gif
Check out the ice get hammered towards the Norths, winds in that region will be highly favorable for that kind of compaction the next couple of days:
Be aware, everytime you're making exaggerations like that you're chopping off a piece of your credibility.
But you are a free man of course.
http://lance-modis.eosdis.nasa.gov/imagery/subsets/?subset=Arctic_r03c01.2012119.terra.250m
Yeah, I probably should have said a polyana has opened up there again. My apologies for exaggerating. My credibility is just fine.
To see something neat click this link:
http://lance-modis.eosdis.nasa.gov/imagery/subsets/?subset=Arctic_r03c05.2012120.aqua.1km.jpg
Then click this one:
http://lance-modis.eosdis.nasa.gov/imagery/subsets/?subset=Arctic_r03c05.2012120.terra.1km.jpg
Then click back and forth and you can see the ice being moved by the wind on a very short time delay, maybe 45 min, hour and half?
It's pretty awesome. The next 3 days or so will be ripe for compaction and more MYI being destroyed.
Posted by: Chris Biscan | April 29, 2012 at 12:41
Nice Kara animation, Chris.
Posted by: Neven | April 29, 2012 at 12:47
And there is the first CT SIA century break (since three weeks exactly), a drop of 126K reported for the 27th.
Posted by: Neven | April 29, 2012 at 13:03
wow, the GFS and Euro smoke the Laptev next week and parts of the East Siberian Sea. The Euro is the stronger of the two with 5 days in a row of a large pressure gradient with a huge 15-25KT wind field that is progged to bring the 0C 850mb line to the shores of the Laptev.
At the southern shores of the Laptev the Sun is above 30 Degrees altitude for 8:30 per day and over 20 Degrees altitude for 12 hours.
If the sun gets out between clouds, there will definitely be some solar energy being dumped into the water if Nilas do not form.
The land is snow packed. However even so models predict as of now have surface temps above freezing over the ice. I suppose with 850s being warm and the ice being blown off the shore's is possible. The temps over the snow pack will likely be above freezing as well.
I wonder if this will be enough to prevent new Nilas growth.
Would the atmosphere transfer enough energy to the water to put a stop to ice growth for a while or until the pattern breaks.
If the Euro tonight panned out, the ice would be pushed for nearly 5 days straight days that is enough time for a shoreline polyannass to develop.
Posted by: Chris Biscan | May 01, 2012 at 09:10
Posted this in the old open thread:
Something else: the plug in Kane Basin (Nares) looks a lot smaller this year than it did last year.
Would the atmosphere transfer enough energy to the water to put a stop to ice growth for a while or until the pattern breaks.
Yes, I also noticed those big highs over Laptev and the East Siberian Sea, but at the same time colder temps (lots of outgoing radiation because of lack of clouds, I guess). It will indeed be interesting to see if those polynyas freeze over again, like they are still doing in the western Kara Sea.
Posted by: Neven | May 01, 2012 at 14:19
MASIE day 121 14,148681km^2, day 113 14,990231km^2.
unless there is something horribly wrong with my maths that equates to an extent drop of 841,550km^2 in eight days.
Posted by: Philiponfire | May 01, 2012 at 17:04
CT is slow to update. In that sense I really miss IJIS. Twice a day around 4 PM and 4 AM (CET) you had your updates. There is no logic to the CT SIA updates.
In the past weeks no updates usually meant big drops or gains (maybe someone is 'manually' double-checking the numbers before they are put), so we could be seeing a couple of century breaks.
On the UB SIC maps Bering is still losing a lot of ice cover.
Posted by: Neven | May 01, 2012 at 17:08
"CT is slow to update. In that sense I really miss IJIS. "
Me, too.
Posted by: Kevin McKinney | May 02, 2012 at 02:08
....so we could be seeing a couple of century breaks
CT might because they are still catching up but DMI extent has been flatlining in the past few days and it is even showing a slight uptick today ( May 2)
Posted by: Phil263 | May 02, 2012 at 12:19
Yes, comparing UB SIC maps, I see a slowdown in the vanishing of Bering sea ice and some ice growth here and there (Hudson Strait, Baffin Bay).
Posted by: Neven | May 02, 2012 at 12:22
Neven wrote:
Yes indeed. Nevertheless, the pace at which the ice mass had been reduced is impressive.
For instance, compared to 2008 there is much less of ice in the Bering sea. And yet in 2008 and 2009 the minimum plunged under the 5 millions km².
On top of that, the Bering Strait seems to become open already (something that happens "normally" in the last week of May).
Easy to compare with the aggiorned
Arctic 1 May parade.
Other than that, 2012 looks a bit less like a Swiss cheese compared to 2011, but that could be a deception.
Meanwhile there is already a sneak previem of the Arctic 1 June parade.
Or both from the bottom here: Arctic parades.
Posted by: Kris | May 02, 2012 at 15:39
Very nice parades, Kris! I might do something similar for the daily graphs page. It's really handy.
Posted by: Neven | May 02, 2012 at 17:03
While awaiting the next update at CT, I did a quick 'scaling' of the NSIDC graph (which is dipping quite dramatically) that yielded a 311,250 sq km drop over some 2.52 days, or 130k per day. As the graph uses 5-day rolling averages, that is then a gauge of the average over the week 25th April to 1st May.
Posted by: Al Rodger | May 02, 2012 at 17:56
NPEO webcams are up.
Posted by: Neven | May 02, 2012 at 18:16
http://i174.photobucket.com/albums/w109/frivolousz21/nhland04-1.png
Northern Hemispheric snow cover was very low for April 2012.
With the forecast for the next 10 days showing torches all over Canada/Russia, expect May to be near the recent record lows.
Posted by: Chris Biscan | May 03, 2012 at 06:59
DMI is straight down on May 3. We may assume that yesterday's slight uptick was a measurement error!
Posted by: Phil263 | May 03, 2012 at 13:16
Ice what ice?
MASIE day 123 13787039, day 116 14798959
which comes to a drop of 1011920km^2 in seven days.
Posted by: Philiponfire | May 03, 2012 at 16:37
MASIE last 30 days
Posted by: DrTskoul | May 03, 2012 at 20:00
Oops... Y scale is in fraction of last 30 day maximum
Posted by: DrTskoul | May 03, 2012 at 20:01
Barents appears to have been smoked!! Where is CT??? how many times do the need to double-check?? Unless there is a wee-bit of a problem like last summer?
Posted by: DrTskoul | May 03, 2012 at 20:04
While ice conditions approached the 1979 to 2000 average levels for this time of year, the high ice extent will have little influence on how much ice melts this summer. Much of the ice cover is recently formed thin ice that will melt out quickly. Research has shown that sea ice extent in spring does not tell us much about ice extent the following summer. More important to the summer melt is the thickness of the ice cover, and summer weather.
http://nsidc.org/arcticseaicenews/
April report is up
Posted by: Philiponfire | May 03, 2012 at 20:31
the Barentsz sea coastal ice was never going to last long. none of it was more than a month or so old. north blowing winds kept blowing the ice out into the atlantic currents where it melted and was replaced near the coast with new thin ice. a repeated pattern all winter.
Posted by: Philiponfire | May 03, 2012 at 20:35
>"Ice what ice?
MASIE day 123 13787039, day 116 14798959
which comes to a drop of 1011920km^2 in seven days."
After that million drop in seven days, the level is still 481k above last year. The main components of that change are:
Barents -209k
Greenland 115k
Baffin 104k
Bering 368k
Okhotsk 145k
Hudson - 31k
Baltic - 32k
https://docs.google.com/spreadsheet/ccc?key=0AjpGniYbi4andFdrTEZrdGVjaXBfWHpIb2VhNHNrM1E#gid=0
Posted by: crandles | May 04, 2012 at 14:34
DMI shows movement again, down by almost 200k from 5/1 to 5/3.
Posted by: L. Hamilton | May 04, 2012 at 14:43