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Neven
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As we look at the breakup of the northern Beaufort sea ice, we see that the, supposedly, predominantly MYI areas are breaking down into floes with approx. 50% of the area around them being open water. Almost exactly what Dr Barber predicted. That being the case, then the satellites overestimated the MYI in that area by approximately 50%. That may be, but don't forget that a late cracking event back in April caused a lot of open water to appear between dispersed floes, which then froze up. This thin ice melted in May and June, and because there were no compacting winds, those MYI floes remained separated.
Neven: The Navy model has a thickness discontinuity in the 30 day run which appears to have a sudden recent correction. The model may still be screwed up but it looks like recent maps don't have the error you just mentioned. I've always found those thickness maps somewhat unreliable or unrealistic, even without parameter problems. And I still think there's something wrong with the current, given all that yellow/green right up to 80N. I look at those maps to see trends. I know that the absolute values are not to be taken literally. Yes, that's always a good thing to do. I use a comparison of these maps too for my winter analyses. The pulling away from the coast of the thick ice causes upwelling from below. This upwelling might be bringing up warmer saltier water which will increase melting. We'll see. It's definitely interesting, also because the fast ice in the CAA has just started to break up now, and with these winds will drift into the gap.
The question whether (weather) July made up for a lack of preconditioning is a good one. What do the melt ponds look like now? Well, like it says in the update CAPIE is relatively low, but there's a lot of dispersal in the Beaufort and Chukchi, so it's not just melt ponds. But 2012 als had quite a lot of dispersal, ie open water between floes, on the Siberian side of the Arctic by now (and then the cyclone came). In fact, Wipneus' compactness graph (which in principle is much more accurate, because it uses area and extent from the same sources) has 2015 as lowest in all three measures: NSIDC SSMIS 25km, JAXA AMSR-2 10 km, and Uni Hamburg AMSR-2 3.125 km. And then there's this, a map produced by the Japanese Arctic Data archive System, based on JAXA AMSR-2 data: I don't know how reliable that map is, but it's interesting and can be compared to data from previous years. Plenty of melting potential.
The 'last thick ice' in a model that has problems: The issue was spurious "SST" observations from the VIIRS satellite under sea ice, due to a new cloud detection scheme at NAVOCEANO that allowed more sun-glint areas (to get more SST observations) but which failed to reject sea ice regions in summer. The model "believes" the data and so SST and sea ice concentration were fighting each other, leading to massive ice melt. The bad SSTs started late in May, so we are going to rerun without VIIRS from May 1st to the present. This is going to take a while to complete. Why do people keep using and linking to this model, when it's obvious it doesn't represent reality for a minute? The open water to the north of the CAA is interesting, but no more than that. That's what you get when winds blow a certain way for weeks on end. When the wind turns, the ice crashes against the CAA again. Now, maybe if this keeps up for another month, we get to see something really interesting.
Also be sure to read RobertScribbler's latest blog post on the current situation and forecast.
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During the melting season I'm writing (bi-)weekly updates on the current situation with regards to Arctic sea ice (ASI). Central to these updates are the daily Cryosphere Today sea ice area (SIA) and IJIS sea ice extent (SIE) numbers, which I compare to data from the 2005-2014 period (NSIDC has... Continue reading
Posted 2 days ago at Arctic Sea Ice
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Working now for me too! Thanks, Neil, you old hacker you. ;-)
Oh dear, this doesn't look good. I remember this article by Webster suggesting a conspiracy of another kind, ie scientists suppressing a paper because it had a 'damaging climate view'. This turned out to be nonsense.
Thanks for this, Jim. I'm glad Wadhams has spoken up about this. This is putting the story in a different light. Now I wonder what Ben Webster has to say about it. Has Webster written news paper articles before that tend towards climate risk denial? The name sounds familiar.
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The second Sea Ice Outlook of this year has been published. The SIO is organized by the Sea Ice Prediction Network (as part of the Arctic research program 'Study of Environmental Arctic Change', or SEARCH), and is a compilation of projections for the September 2015 Arctic sea ice extent, based... Continue reading
Posted 7 days ago at Arctic Sea Ice
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I no longer believe in the "ice is so thin that weather does not matter" as I used to before 2014. I assumed this was the case because of events during the 2011 and 2012 melting seasons. This depends, of course, on initial ice thickness. But preconditioning plays a very important role after that.
Toggle Commented Jul 21, 2015 on Junction June 2015 at Arctic Sea Ice
Thanks, D.
What is your opinion of the new computer model of the Solar cycle, which predicts a new Maunder minimum starting in the 2030 to 2040 decade? I guess it's me you're addressing. I'm not an astrophysicist, but I figure this tweet from Gavin Schmidt makes sense (posted by someone on the forum): "A period in the late 17th C (the "Maunder minimum") had very few sunspots, smaller amplitude 11-yr cycles & perhaps reduced irradiance. Combined with an increase in volcanic activity, these natural drivers are implicated in the relative coolness of the 'Little Ice Age'. The result being discussed is a statistical prediction of a '60%' reduction in the magnitude of the next few solar cycles. For context, climate forcing over a solar cycle is about 0.175 W/m2. Current forcing from CO2 is more than 10 times larger. 60% reduction in solar cycle magnitude wld be a climate forcing of -0.1 W/m2. Equivalent to a decrease of 8ppm CO2 (~3 years worth). Thus, at max, the predicted solar cycle change will slow GW by about a few years, and has no chance of causing a 'mini ice age'." Like you say, it will last between 20 and 30 years. What happens after that? Most probably accelerated warming.
Thanks, Jim. I've added that third video to the blog post.
Over on the Arctic Sea Ice Forum commenter Jim Hunt from the Great White Con blog posted videos he made, showing developments since the start of the month in the Northwest Passage (where the blue ice is breaking up fast): Events since April 1st in the Beaufort Sea have been... Continue reading
Posted Jul 18, 2015 at Arctic Sea Ice
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I don't agree, Philip. A rebound is not the same as a recovery. It is 'normal' for sea ice to rebound after a record, especially after record smasher 2012 (which, of course, was also a weather event on the ongoing trend, if we're going to look at it that way).
Toggle Commented Jul 18, 2015 on Junction June 2015 at Arctic Sea Ice
Well, there is no more lag now that Wipneus pre-calculates CT data based on NSIDC extent data. But I divide SIE numbers by the SIA numbers on the same date. CT SIA dating is a bit confusing so there might be a 1-day offset. Wipneus' compactness graphs are superior, because of lower resolution and SIE and SIA coming from the same provider.
Toggle Commented Jul 16, 2015 on Junction June 2015 at Arctic Sea Ice
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Melt pond May alliterates well and the name conveys what it's about: the time when melt ponds first start to form. Luckily, a couple of weeks ago, someone on the forum (forgot who, but thanks!) helped me find a perfect alliteration for June: Junction June. This name refers to the... Continue reading
Posted Jul 16, 2015 at Arctic Sea Ice
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Bryant, like Jim says, there is no 'you guys'. Please, cease the attempts at creating conflicts on this blog. I don't expect the Arctic to go ice-free for all practical purposes this year, or any specific year to come, but I do see the contours of how it could come about. As long as volume hovers around a certain number, one might say the Arctic is open to the possibility. Of course, it will take exceptional conditions to persist for weeks on end, like the heat we are currently seeing, but preceded by a much more intense of preconditioning (and a winter with lower volume, etc), and followed by major compaction or a big, big cyclone. It's a combination of factors that's rarely seen, but when it will be seen, the Arctic sea ice will go with a bang. Of course, this will be a fun and fascinating spectacle to watch (if you don't think about the implications) and it will be a huge blow to the climate risk denier position, a Pearl Harbor moment, so to say. A lovely reward for all their hard work. But a very important point is this: it's already bad. The consequences of Arctic sea ice loss are already upon us, locally and beyond. It's already worrisome enough as it is for anyone who honestly thinks it through. All we can do, is hope that at least the mainstream position of 'after 2030' is more or less correct, and we don't see that freak year before. But if it comes, it comes. I don't see it as a bad thing necessarily. The thought of Arctic sea ice loss informs my actions and motivates me to make changes to my lifestyle, actually improving my health and life in general and making me a better, more independent citizen, strengthening democracy. I hope it's the same for others. There's a bright future ahead of us, if we want it. But not an easy one.
Toggle Commented Jul 14, 2015 on PIOMAS July 2015 at Arctic Sea Ice
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The fast ice in Nares Strait is finally giving way, relatively late again compared to recent years, after staying open over winter for a relatively long time as well. In the period the ice arch finally formed, it even got pushed back and forth a bit, probably making it stronger.... Continue reading
Posted Jul 13, 2015 at Arctic Sea Ice
Everyone, there's still a couple of hours left to vote or change your vote on the NSIDC 2015 Arctic SIE September minimum: July poll. Let's make it 100 voters again!
Toggle Commented Jul 12, 2015 on ASI 2015 update 4: massive heat at Arctic Sea Ice
Well done, Rob. My compliments.
I just remembered an instance in the past couple of years where we also thought it were paw prints and then it turned out that they were human footprints revealed by the melting snow. This current image looked similar to me like that, but it might be ice bear prints. Edit: Polar bear prints. Dutch word for polar bear is 'ijsbeer'.
Toggle Commented Jul 12, 2015 on ASI 2015 update 4: massive heat at Arctic Sea Ice
Tenney, I don't think the PIOMAS volume numbers can be off by much. At least, they make sense to me, in conjunction with other data. It's one of the best tools we have. Of course, observations would be even better, but CryoSat-2 has its own problems and doesn't report during summer.
Toggle Commented Jul 11, 2015 on PIOMAS July 2015 at Arctic Sea Ice
An alien wearing human shoes.
Toggle Commented Jul 10, 2015 on ASI 2015 update 4: massive heat at Arctic Sea Ice