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Good explanation of the main dynamics of the season.
Looking at PIOMAS anomaly in comparison to recent years, the slope of the graph indicates that relative volume loss started backing off in mid-July. This measure may not be a proxy for melting momentum, but it seems to indicate that something else was going on besides the August slowdown discussed above.
PIOMAS September 2019
Apologies for this late update, but at least it will give me the opportunity to give my opinion/analysis of how this melting season has evolved, now that the minimum is just around the corner. It also gives me the opportunity to announce that the Arctic Sea Ice Forum recently passed the 100 mill...
The last image is about the worst indicator I've seen for volume this season, especially with southerly winds near FJL for at least the next week.
PIOMAS June 2019
Another month has passed and so here is the updated Arctic sea ice volume graph as calculated by the Pan-Arctic Ice Ocean Modeling and Assimilation System (PIOMAS) at the Polar Science Center: As you can see, 2019 has moved into second place on the PIOMAS volume graph. The drop of 3234 km3 for...
Nice work, especially highlighting Oren's contribution.
Looks like Greenland Sea has flipped from being a negative to a positive for ice volume later in the season, unless Fram export picks up again.
PIOMAS July 2018
What a coincidence. Just like last month, I will have to precede the PIOMAS update with a short news flash that a very strong cyclone is barreling through the Arctic. But this time too, the cyclone will be short-lived, and so it's not entirely clear whether, on the whole, it will be damaging or ...
Just catching up on developments, wanted to add my note of appreciation to Neven as well as the commenters.
Any thoughts on providing context for the max-min graph? maybe show alongside min-max for the previous freezing season?
PIOMAS October 2017
To make up for this somewhat belated PIOMAS update (below), I have for you Andy Lee Robinson's latest update of his Volume ice cube 3D video: ----- Another month has passed and so here is the updated Arctic sea ice volume graph as calculated by the Pan-Arctic Ice Ocean Modeling and Assimilation...
Good catch Lodger, thanks for the correction. I wonder whether there is some way to derive data from the Tschudi ice age model to quantify the change in MYI melting within the Arctic vs. being exported. The animation on Climate.gov certainly supports your point.
https://www.climate.gov/news-features/videos/old-ice-arctic-vanishingly-rare
Rob, generally agree with your assessment, though it omits the unknown (and possibly greater) influence of snow cover over sea ice. Would that we had better observational data.
Guest blog: Arctic Prediction Models
Here's another guest blog, sent to me by Lewis Clark, who is also a commenter on the Arctic Sea Ice Forum. Lewis describes this year's melting season and how several forecasts have played out in relation to it. I like the term 'thin ice age'. Thin ice makes it more difficult to rely on conventio...
At this late date and under near-neutral conditions, it shouldn't be too hard to pick a number. But I'm still baffled by the factors in opposition: concentration vs. thickness distribution, among others. Thinking on a V-shaped extent minimum, which would require compaction continuing beyond next week and a further push from bottom melt. So I'll guess 4.1 million km2 for the JAXA daily min you linked to.
Interestingly, on the other poll's measure of NCSID September average extent, the SIPN August Report's median of 4.54 million km2 is up slightly from July's, but still low enough for a 3rd-place finish.
https://www.arcus.org/sipn/sea-ice-outlook/2017/august
Guest blog: Arctic Prediction Models
Here's another guest blog, sent to me by Lewis Clark, who is also a commenter on the Arctic Sea Ice Forum. Lewis describes this year's melting season and how several forecasts have played out in relation to it. I like the term 'thin ice age'. Thin ice makes it more difficult to rely on conventio...
Yes, less alarming than it looked a couple of months ago. Yet volume anomaly still hit a record low during June. And as others have noted on the Forum, the picture appears worse if you give any credence to inferring volume from Hycom.
Further to Jim P's projection, one question is what path volume might follow to a new record minimum. Based on the thickness distribution, it looks like July would run ahead as the Atlantic-side melt picks up pace, followed by a slower August (that is, volume anomaly would turn up more steeply). OTOH if low-pressure systems predominate, they would give the central pack some measure of protection during July (which looks to happen in the coming week or so). But a deeper low during August would intensify wind-and-wave melting.
I'll refrain from guessing on this one: depends on the weather.
PIOMAS July 2017
Another month has passed and so here is the updated Arctic sea ice volume graph as calculated by the Pan-Arctic Ice Ocean Modeling and Assimilation System (PIOMAS) at the Polar Science Center: Last month we finally received some good news from PIOMAS, and the good news continues this month. Wi...
@DavidR,
Good reasoning to bias the projection toward more recent years. Archimid's graph of volume gain during the freezing season (post #1726 in ASIF PIOMAS thread) shows an increasing trend with a possible step-change around 2008. Conversely that implies even larger peak-to-trough losses since then. Also iirc, Chris Reynolds argued for a regime change in ice dynamics following the extreme 2010 volume loss.
Eyeballing Wipneus' PIOMAS chart, there seems to be a tendency for the largest (negative) volume anomalies to revert more. But it's not at all consistent, and doesn't necessarily happen before the melt-season minimum. No sign of reversion at all so far this year.
PIOMAS June 2017
Another month has passed and so here is the updated Arctic sea ice volume graph as calculated by the Pan-Arctic Ice Ocean Modeling and Assimilation System (PIOMAS) at the Polar Science Center: Finally some good news, relatively speaking. The cold that crept over the Arctic during the last week...
Good summary of a critical metric at a pivotal time.
One thing that catches my eye is the range of trajectories in Jim Pettit's graph. If a neutral expectation for volume minimum is in the middle of the pack, a regression assumption (i.e., moderation of the current extremely low anomaly) would land somewhere above the middle: safely higher than the record low. But it doesn't feel like that assumption is valid this time. Low average thickness, thicker ice heading for the exits, and the seeming likelihood of melt ponding over first-year ice that extends well into the pack... not good at all.
PIOMAS June 2017
Another month has passed and so here is the updated Arctic sea ice volume graph as calculated by the Pan-Arctic Ice Ocean Modeling and Assimilation System (PIOMAS) at the Polar Science Center: Finally some good news, relatively speaking. The cold that crept over the Arctic during the last week...
The nearly-unchanged anomaly is bad, the flattening thickness graph is worse, and the spatial distribution - if PIOMAS is even approximately correct - is terrible.
PIOMAS April 2017
Another month has passed and so here is the updated Arctic sea ice volume graph as calculated by the Pan-Arctic Ice Ocean Modeling and Assimilation System (PIOMAS) at the Polar Science Center: Just like last month, there haven't been any major changes, and that's good, because it means things ...
"Eggbeater August"
2016 Arctic cyclone, update 2
So, the storm has been raging for a while now. The latest Environment Canada weather map shows it's at 984 hPa. According to this tweet by PhD climatologist Brian Brettschneider a IABP buoy from the University of Washington measured a lowest central pressure of 966.5 hPa, which is somewhat lower...
This is a good analysis of the puzzlingly high melt rates - especially on AMSR2 data - under what seem to be middling weather conditions.
As for sea surface temperatures, the current distribution seems more favorable for ice retention than 2012 or 2015. This coming week again looks to bring relatively low heat advection from Kara/Barents (except for a couple days of rain over Laptev) or from south of the Bering Strait.
ASI 2016 update 4: breaking point
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...
The ice motion anomaly graph is quite useful; corroborates the explanations others have given for more thick ice in ESS and Laptev. Also noteworthy that volume hit a record low this spring despite lower-than-average Fram Strait export. This underscores the dominant influence of the warm winter.
PIOMAS July 2016
Another month has passed and so here is the updated Arctic sea ice volume graph as calculated by the Pan-Arctic Ice Ocean Modeling and Assimilation System (PIOMAS) at the Polar Science Center: As expected after a month of stalling sea ice extent and weather that generally isn't conducive to se...
Edit: Wayne, I see that Neven's response above is more on point to your question. The anomaly graph on Wipneus' PIOMAS page shows how volume differs from the historical average for each day of the year. This highlights the volume counterpart to the "June cliff", discussed elsewhere (more in reference to area or extent, iirc).
OSweetMrMath's is the next refinement - he gives a good explanation; I think of it as "How is daily volume different than it would be if the year were in line with both the seasonal cycle and the long-term trend?"
See also Tamino's similar treatment for ice extent:
https://tamino.wordpress.com/2016/05/16/arctic-dive/
PIOMAS June 2016
Another month has passed and so here is the updated Arctic sea ice volume graph as calculated by the Pan-Arctic Ice Ocean Modeling and Assimilation System (PIOMAS) at the Polar Science Center: As of May 31st the 2016 trend line is lowest on the graph. A sea ice volume decrease of 3037 km3 duri...
@ Wayne Kernochan
If I understand your suggestion correctly, that's just what OSweetMrMath did on the PIOMAS thread on the forum (post #914). His detrended anomaly graph is fascinating.
http://forum.arctic-sea-ice.net/index.php/topic,119.900.html
As for the conventional anomaly graph above, 2016 has tracked fairly parallel to 2014 so far. My guess is this will continue in June (i.e., anomaly falling but at slower rate).
PIOMAS June 2016
Another month has passed and so here is the updated Arctic sea ice volume graph as calculated by the Pan-Arctic Ice Ocean Modeling and Assimilation System (PIOMAS) at the Polar Science Center: As of May 31st the 2016 trend line is lowest on the graph. A sea ice volume decrease of 3037 km3 duri...
Although I take Rob's numbers seriously, I disagree with his conclusion. First, some fraction of the insolation heat will go into the atmosphere and be carried over the Chukchi and beypnd. Second, with area/extent in the Beaufort already far below normal, the graph is likely to flatten soon as the gyre moderates and temperature anomalies become less extreme.
So the coastal ice that Neven highlights, as precarious as it looks for the next few days, is more likely to hang on through most of June.
Beaufort final update
This isn't a final update as such, because I will certainly be mentioning events in the Beaufort Sea in upcoming ASI updates. But it is the last in a series of blog posts I have written (one, two and three) about this unprecedented event that started over 6 weeks ago and has led to a heavily cra...
Thanks for advocating for observation-based melt pond research, Neven. We really need that early-warning system. I like Yvan Dutil's suggestion of crowdfunding, but am not sure there's sufficient interest outside this and other like-minded communities. Maybe the wealthy homeowners of Miami Beach and Mumbai will kick in?
EGU2016, my impressions
Just like last year, I had the opportunity and time to visit the European Geosciences Union General Assembly 2016. There were several sessions on subjects related to the cryosphere and remote sensing, but most of the interesting Arctic sea ice-related stuff was happening on Thursday. So, that's...
It will be interesting to see the timing of the coming downturn in Barents relative to blips upward in Greenland and Okhotsk. The real wild card, though, is the large proportion of thin ice in Baffin/Newfoundland and what fraction of the recent melt/compaction crosses back over the 15% margin later this week.
The Ns are calling the maximum
Here's a quick update on everything related to our good friend Max. In the past couple of days organisations like the NSIDC, NASA and NOAA have announced the annual event of the Arctic sea ice pack reaching its largest size at the end of the freezing season. This has been picked up widely by the...
There's a lot of ice cover close to the 15% cutoff in Baffin and St. Lawrence, and increasingly in Bering. All three regions show a recent divergence between JAXA and UH AMSR2 in Wipneus' charts. The former appears to be counting extent near the fringe in places where the latter is not. This has occurred in prior years, probably owing to differences in grid cell size.
Early record, late record
10 days ago I posted a blog post called Mad max. The title - referring to a very early maximum sea ice extent - ended with a question mark, because it was far from sure whether the preliminary max reached on February 15th would remain standing. This is because of the oscillatory nature of the f...
Can't say for certain that we'll have the final answer within a week, even though it's quite late in the season. Conditions look favorable for extent increases for a few days around the 25th. It's quite possible the number will be just below the 15th Feb peak and nosing up toward it - rather like a polar bear cruising beneath the ice, getting ready to pick off a hapless seal on the surface.
Early record, late record
10 days ago I posted a blog post called Mad max. The title - referring to a very early maximum sea ice extent - ended with a question mark, because it was far from sure whether the preliminary max reached on February 15th would remain standing. This is because of the oscillatory nature of the f...
Looks like conditions are in place for an early volume peak: high anomaly, above-normal air temps in the forecast, and lots of ice getting pushed out into warmer waters during the latter part of March. I'll put in a guess that the max arrives the first few days of April, which would be earliest in recent decades if I'm reading PIOMAS graphs correctly.
PIOMAS March 2015
Another month has passed and so here is the updated Arctic sea ice volume graph as calculated by the Pan-Arctic Ice Ocean Modeling and Assimilation System (PIOMAS) at the Polar Science Center: The red trend line for 2015 is clearly levelling off during the second half of February, coinciding w...
Interesting that this year will have either the earliest extent maximum or (perhaps) the latest. It's an extreme instance of a sinusoidal characteristic that OSweetMrMath pointed out on ASIF: the function is flattish near its maximum, which makes the timing hard to predict.
Mad max?
Okay, I'm not calling the max - short for maximum extent of the sea ice pack that marks the end of the freezing season - as I've sworn not to do that anymore since 2012, when I called the max twice, only to see the trend line bounce up higher and later. But this year something really interestin...
edit: gains in Bering not Barentsz
Mad max?
Okay, I'm not calling the max - short for maximum extent of the sea ice pack that marks the end of the freezing season - as I've sworn not to do that anymore since 2012, when I called the max twice, only to see the trend line bounce up higher and later. But this year something really interestin...
@Neven "Plenty of snap potential, but first all of this 'heat' (it's temperature anomaly, so still plenty cold, just not megacold) needs to get out of the way, and by the time it does, it'll probably be too late for a snap:"
This will be entertaining to watch. A week from now the extent gains in Barentsz and Baffin/Newfoundland will be trailing off or reversing. Looks like not much contribution from Okhotsk by then. Meanwhile an extent drop in Kara from melting and compaction. Will Kara refreeze before the newly-formed thin ice melts elsewhere?
Mad max?
Okay, I'm not calling the max - short for maximum extent of the sea ice pack that marks the end of the freezing season - as I've sworn not to do that anymore since 2012, when I called the max twice, only to see the trend line bounce up higher and later. But this year something really interestin...
The animation is indeed quite striking.
Someone posted a statistic on ASIF a while back of the percentage that Fram export accounts for of total annual peak-to-trough volume change. I don't remember the number but it's fairly small (~10%?). However, it seems likely that Fram export can have a disproportionate effect on the melt season. A strong export in the spring, for example, would thin out ice in the central basin and make it more susceptible to insolation.
Fram Strait 2014
Wipneus, creator of many graph and animations, has posted another gem over on the Forum. The animation he uploaded to Youtube becomes really interesting after the end of May, when the transport through Fram Strait (one of the reasons that made the 2007 melting season so spectacular) almost compl...
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