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John, the data I used for those graphs can be found here.
Toggle Commented Oct 17, 2016 on The 2016 melting season in images at Arctic Sea Ice
David, here's a good paper on that: Comparison of Arctic Sea Ice Thickness from Satellites, Aircraft, and PIOMAS Data (PDF) Or check out this poster by Zachary Labe: Making the most of Arctic sea ice observations (PDF)
Andy Lee Robinson has updated his PIOMAS sea ice volume minimum video: Continue reading
Posted Oct 15, 2016 at Arctic Sea Ice
Maybe it is time to start a 'forum' topic on this work, or, Neven, will you still be posting a new ASIB post on the Walsh historic sea ice reconstruction ? I will be publishing a blog post this weekend. Sorry for taking so long.
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 minimum was reached in September for modelled sea ice volume as well, and 2016 came in third,... Continue reading
Posted Oct 11, 2016 at Arctic Sea Ice
Neven, here's another one for you - PIOMAS results just came out for September: Thanks, Andy! What a coincidence. I thought about you today, and that piano piece you wrote to accompany your Arctic death spiral video.
I hope they make it back safe, Jim! I was happy to see them making it, especially after all the lies that had been spread wrt their expedition. Vid, I've forgotten many more things, all of them equally (un)important. I appreciate you've taken it upon you to make people aware of the annual average graphs. Great summary of a fascinating year. It's going to be interesting to see when the Northwest passage closes this year - temperatures are still mostly too high for meaningful freezing... and it was close to or above zero at the north pole yesterday. Indeed, Robert. This autumn is already fascinating, what with the rapid refreeze and anomalous temps. I'm worried that Europe may experience some extreme winter weather events in months to come. Also because I still don't have proper heating in my house. ;-)
The Arctic year started with the warmest January and February on record: The mild winter led to one of the lowest maximums on record, lowest even on some graphs. And then in April, just before the melting season started, things got exciting very early in the Beaufort Sea (animation shows... Continue reading
Posted Oct 4, 2016 at Arctic Sea Ice
You mean to Andrew Slater? I don't know. Someone mailed me and wrote that he was found in his home. So my guess is a heart attack or some such.
Toggle Commented Sep 26, 2016 on In memoriam: Andrew Slater at Arctic Sea Ice
Neven, I'm not sure I grasp the difference between save and bring back. If u can bring back sea ice, surely that amounts to saving it? I guess that technically speaking 'bring back from the dead' and 'save' are the same thing. But there's a difference between 'bring back from the dead' and 'prevent from dying'.
Toggle Commented Sep 20, 2016 on ASI 2016 update 7: minimum time at Arctic Sea Ice
Last week, NSIDC scientist Andrew Slater died unexpectedly. It goes without saying that the news shocked me, and I wasn't the only one (here's the memorial web page). I had never met him, although we mailed once or twice in the past year. He also occasionally commented on the Arctic... Continue reading
Posted Sep 19, 2016 at Arctic Sea Ice
Gerald, it's not really hope. There are just some things we can't foresee, and so I'm open to the possibility that some things can be salvaged. Not the ice, I don't think it can be saved. But maybe we can bring it back. That's why it's important that we're watching and learning about it.
Toggle Commented Sep 19, 2016 on ASI 2016 update 7: minimum time at Arctic Sea Ice
Wipneus is back, and so are his calculated CT SIA numbers: The minimum was reached September 9th, at 2.421 million km2, well below the previous nr 2 (2011: 2.905 million km2). It's the only time in the past decade that JAXA SIE reached its minimum earlier than CT SIA (just one day), which tells us something about dispersal.
Toggle Commented Sep 14, 2016 on ASI 2016 update 7: minimum time at Arctic Sea Ice
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... Continue reading
Posted Sep 13, 2016 at Arctic Sea Ice
Unfortunately, some very sad news. It seems Andrew Slater has died unexpectedly. I'm at a loss for words right now, but I'll try and write something later this week.
Toggle Commented Sep 12, 2016 on PIOMAS September 2016 at Arctic Sea Ice
Chris Reynolds also just posted about an oscillation in August extent loss.
Toggle Commented Sep 12, 2016 on PIOMAS September 2016 at Arctic Sea Ice
Please could you clarify your remark? Jim, vid refers to 'year–to–date and 365–day annual averages'. Tamino also has some graphs in this latest blog post.
Toggle Commented Sep 11, 2016 on PIOMAS September 2016 at Arctic Sea Ice
Sea ice area has the same 15% thing.... Which means that everything below 15% is considered zero. But unlike extent - where everything above 15% is considered 100% covered - it's not an either/or proposition (either 0% or 100%). Every metric is useful, and no metric is the Holy Grail. We saw the same kind of dispersal in 2010 and 2013, and at the time I calculated how much lower extent would be if the holes within the pack were counted. It was somewhat lower, but not hugely so. If someone can quantify for this year, that would be nice, but don't expect this year to be as low or lower than 2012, because Wipneus' AMSR2 SIA (3.125 km resolution) clearly shows this year to be higher. Speaking of which: I hope Wipneus' move to his new home has proceeded in orderly fashion, and he can soon resume the magnificent job he's doing. I'm starting to miss his data!
Toggle Commented Sep 11, 2016 on PIOMAS September 2016 at Arctic Sea Ice
Should that read "2014 and 2015"? Yes, it should. Thanks, Bill. Fixed now. Thanks for the excerpt, vid. I might go and buy that book.
Toggle Commented Sep 3, 2016 on PIOMAS September 2016 at Arctic Sea Ice
PIOMAS is clearly overestimating thickness along the Wrangel arm, even in areas where satellites show very low ice concentration, with most ice floe sizes below the 250m resolution of MODIS. Expect PIOMAS minimum under 2011 as soon as the model assimilates the melt out of these ice extensions (if only). I agree, navegante, that whether 2016 will go below 2011, will largely depend on what happens to the ice in the Wrangel Arm. As you can see on this thickness anomaly map that is also posted on the PSC PIOMAS website, that zone is still considered to have a lot of volume, in comparison to the 2000-2015 average (click for a larger version): If that red blob north of Wrangel Island goes, volume might dip just low enough to overtake 2011. But I'm not sure if all the ice will disappear, given the current weather forecast.
Toggle Commented Sep 3, 2016 on PIOMAS September 2016 at Arctic Sea Ice
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: Weather conditions in the past month - the (Great?) Arctic Cyclone followed by the Mega-Dipole to be precise... Continue reading
Posted Sep 3, 2016 at Arctic Sea Ice
I hope you'll accept my apologies. Okay, fair enough, Vid. And I see your annual average stuff as a useful source of information, a piece of the puzzle. That's the reason why I've always given you some leeway. As for the influence of the pre-preconditioning (early opening up in the Beaufort, rapid snow cover retreat, etc) on how this melting season will end up, I'm still not sure how much of it was also influenced by ocean heat flux, an element that is impossible to get a handle on. I mean, if I look at SST anomalies, it's as bad or slightly worse even than in 2012, but things were rather cloudy when the Sun was high up in June and July. So where did all that heat come from? Mind you, it's ocean heat flux that got Maslowski's model to predict a 80% drop from the 1979–2000 summer volume baseline somewhere between 2013 and 2019.
Toggle Commented Aug 31, 2016 on 2016 Mega-Dipole at Arctic Sea Ice
Perhaps one of you could either shift it or re-post it? Bill, the Typepad software doesn't allow me to move comments like that. As for my good friend, absolute genius, and judge of all, Vidileo Vidilei: If your annual average oracle has been lowest all year, then why doesn't this year's minimum crush the 2012 record? Or maybe I shouldn't ask about physical details when it comes to black-and-white sweeping stats? I will readily admit that I personally didn't expect the pre-preconditioning momentum would take things so far, given the lack of melt ponding during June and July. And of course, I couldn't foresee with any certitude the spectacular end to the melting season, due to the GAC (or close to it) and the current Mega-Dipole. But I never ruled out anything either. You can read back the introductions and conclusions of all ASI updates this year. I always explain the range of possibilities, even if they seem far-fetched at that moment. In fact, on May 27th (2016 ASI update 1) I wrote: 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. I don't understand why you're so intent on smearing my reputation? Am I not alarmist enough for you? Why not go to the Sam Carana blog then? It's much more your style. Especially your extrapolated zero ice on August 1st 2023 will be popular there.
Toggle Commented Aug 31, 2016 on 2016 Mega-Dipole at Arctic Sea Ice
If line drawing using Arctic wide data did not work back then, why is it a valid method today for predicting future ice levels in the next three years? William, I'm not a fan of line drawing either, and you can see I'm fairly reticent most of the time. The stats of an incredibly rapid loss of Arctic sea ice so far, only tell part of the story, but the reason people are going out on a limb so much, is right here in front of you. Heat is accumulating in the atmosphere and oceans, and a lot of it ends up in the Arctic, causing Arctic amplification. That's how you get the mild winter we have just experienced, which will most probably only get milder more often as years go by. This year, that winter was followed by a very early and massive opening up of the ice pack on the Pacific side of the Arctic, and very warm waters on the Atlantic side of the Arctic that pushed the ice pack's edge back, well past Svalbard. If this then gets followed by early, widespread melt onset and then melt ponding, like we saw back in 2012, the ice pack is primed for very large losses in August. Make that an August with GAC-like conditions like we just saw, followed by a persistent Mega-Dipole, and you get... ...well, awfully close to ice-free conditions. So, as much as I'm not a fan of extrapolating exponential or even linear curves, and I really dislike it when people announce an ice-free Arctic every year, I'm not excluding the possibility that one freak year, consisting of various elements of the most 'successful' melting seasons so far, could cause the Arctic sea ice pack to measure less than 1 million km2 in September. All that needs to happen, is for a freak year to come early. I would say the required conditions (volume, etc) are very close for making that possible, if not there already. Personally, I don't think it will happen before 2020, but I'm not ruling it out. Either way, anything before 2050 is really bad and much earlier than was predicted just 10 years ago (except by a handful of outliers that are generally mocked).
Toggle Commented Aug 30, 2016 on PIOMAS August 2016 at Arctic Sea Ice
Thanks for posting these local weather data and their context, Olivier. It's something I always wanted to do, but never had the time for. Not to find all the sources for the various weather stations, let alone checking them daily.