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Neven
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Mid-month PIOMAS update over on the ASIF.
Toggle Commented 7 days ago on PIOMAS July 2017 at Arctic Sea Ice
I would say it's because there's less 'easy ice' on the periphery.
Toggle Commented Jul 13, 2017 on PIOMAS July 2017 at Arctic Sea Ice
I don't know, Bill. What would Van Gogh say? :-P
Toggle Commented Jul 8, 2017 on Melting momentum: May 2017 at Arctic Sea Ice
suggests still 5.41 M km^2 for September 2017 Wow, Rob, that's even higher than David Schröder's 5.1 (4.6 to 5.6) million km2. Higher than every ear since 2006, and higher even than rebound years 2013 and 2014. But this year so far hasn't been nearly as cold /cyclonic as 2013 or 2014, and according to PIOMAS volume is still lowest on record, after the mildest winter on record. And then there's all that early, open water on the Siberian side of the Arctic and SSTs starting to respond strongly (not that far behind 2012 and 2016). This year appears to be a serious test for my (mostly land-snow cover based) prediction method. Yes, it's a test for the influence of snow, and its potential as a negative feedback.
Toggle Commented Jul 7, 2017 on Melting momentum: May 2017 at Arctic Sea Ice
Which is also one of the reasons I'm on a sabbatical (except for these monthly PIOMAS updates and when there's something I cannot not write about). But the 'problem' isn't that my heart isn't in it anymore, it's that my heart wants to do more than just describe the spectacle of Arctic sea ice loss (which inevitably becomes formulaic, as there are only so many ways you can describe this process).
Toggle Commented Jul 7, 2017 on PIOMAS July 2017 at Arctic Sea Ice
Dr David Schröder from the University of Reading has sent me the modelled melt pond distribution maps for June. I've posted them as well as my thoughts (and weather forecasts for the next week) on the 2017 melting season thread, over on the ASIF. Dr Schröder writes: Based on melt pond fraction in May+June we predict a mean 2017 September ice extent of 5.1 (4.6 to 5.6) mill km2 (within the range observed during last 4 years). The likehood for a new record minimum is below 1% [my emphasis; N.]. While melt pond fraction has been above 2006-2015 mean values in the western parts of the Arctic, less ponding and melting occurred in the eastern part (see anomaly figures attached) due to more snow and relatively cold temperatures. In the past the regions - where melt pond fraction is low in 2017 - were more important for September ice extent (local pond fraction in areas enclosed by thick contour line show a negative correlation with mean September ice extent of R < -0.3) than e.g. the Beaufort Sea. Consequently, we predict the September ice extent to be quite large in spite of the lowest Arctic ice volume in recent months.
Toggle Commented Jul 6, 2017 on PIOMAS July 2017 at Arctic Sea Ice
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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. With... Continue reading
Posted Jul 4, 2017 at Arctic Sea Ice
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Thanks, Jim. And next week I'll be showing how both these forecasts fared (for June 24-29), when compared to what happened from day to day. It's high time I learned some more about weather forecasting. ;-)
Toggle Commented Jun 23, 2017 on Melting momentum: May 2017 at Arctic Sea Ice
You should be able to find it on the Stoat's blog, D.
Thanks, John. Since 2012, we haven't seen a melting season with a high amount of preconditioning through melt ponds. Maybe it's a sign of some negative feedback kicking in. Last year still went low despite this lack of melting momentum, and this year the ice is supposedly thinner than it has been (although the gap between 2017 and 2012 has rapidly disappeared, according to the latest information on the ASIF). And there's already a substantial amount of open water in the Beaufort, Chukchi, East Siberian and Laptev Seas. So, while there's a lack of melt pond formation, it may be that the influence thereof is becoming less of a factor. In this sense, and as always, it will be interesting to see how things play out this year. Of course, once we get a year that is low volume-wise and heavy preconditioning at the start of the melting season...
Toggle Commented Jun 19, 2017 on Melting momentum: May 2017 at Arctic Sea Ice
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Here's a blog post I just read on Andreas Muenchow's Icy Seas blog: Is Petermann Gletscher Breaking Apart this Summer? I am disturbed by new ocean data from Greenland every morning before breakfast these days. In 2015 we built a station that probes the ocean below Petermann Gletscher every hour.... Continue reading
Posted Jun 16, 2017 at Arctic Sea Ice
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Another factor pointing to a possible rebound: concentration is looking better than the same time last year: Paddy, I think that this is another indication of low melt ponding. Normally, when the ice starts to turn bluish, that's also the start of large swathes of green/yellow/pink on the Uni Bremen SIC map. Because these swathes do not stay in the same place (most of the time), they're not really an indication sea ice concentration (ie open water vs ice), but rather of melt ponding.
Toggle Commented Jun 13, 2017 on Melting momentum: May 2017 at Arctic Sea Ice
I'm tempted to think that melt ponding may be less critical this year, because that thinner ice may be going no matter what... That could very well be true, Robert. And I'm definitely not saying that this is putting a spanner in the works of a new record. Let me put it this way: If there was extensive melt ponding going on right now, building up lots of melting momentum for July and August, I'd be willing to bet (big) money that this year all records will be broken. As it is, everything is still open. Melt ponding could still get going, or like you say, it may not matter all that much because so much of the ice is thin. One other thing speaking for 2017 staying a very serious contender, is the current weather forecast. Although the spell of (relatively high) high pressure is now coming to an end, it's not like low pressure is taking over. In fact, it seems a weak dipole is going to form over the coming week. SSTs are also on the rise. I'm waiting for June 15th to come around, as I have DMI SST anomaly maps for that date from 2012 and 2016.
Toggle Commented Jun 13, 2017 on Melting momentum: May 2017 at Arctic Sea Ice
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Here's a quick blog post, which is mostly a copy of a comment I just wrote on the 2017 melting season thread on the Arctic Sea Ice Forum. For those who want to know more about what melting momentum means, read these blog posts from 2015 and 2016. I've been... Continue reading
Posted Jun 12, 2017 at Arctic Sea Ice
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For those who like to share what they think this melting season's outcome will be, two June polls have been put up on the Arctic Sea Ice Forum (there will be new polls at the start of July and August): JAXA 2017 Arctic SIE September daily minimum and NSIDC 2017 Arctic SIE September average Happy voting!
Toggle Commented Jun 3, 2017 on PIOMAS June 2017 at Arctic Sea Ice
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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 of... Continue reading
Posted Jun 3, 2017 at Arctic Sea Ice
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Call me in about 15 years. Okay, we'll call you then! Bye. :-P
Toggle Commented Jun 1, 2017 on PIOMAS May 2017 at Arctic Sea Ice
For those who like to share what they think this melting season's outcome will be, two June polls have been put up on the Arctic Sea Ice Forum (there will be new polls at the start of July and August): JAXA 2017 Arctic SIE September daily minimum and NSIDC 2017 Arctic SIE September average Happy voting!
Toggle Commented Jun 1, 2017 on PIOMAS May 2017 at Arctic Sea Ice
It is time to reflect the sorry nature of sea ice and those intending in seeing it disappear further by their misconceptions. Absolutely, Wayne, and I'm going to try to be back again next year, and maybe try some other stuff as well. I'm quite active on the ASIF, but not having to write hundreds of words every week (besides the hundreds of translated subtitles I make for work) is doing me a tonne of good, mentally. I'm making some progress on the house as well. With a bit of luck I'll be done with the big projects around this time next year. BTW, today I had the honour of appearing on Austrian radio for a couple of minutes to talk about Arctic sea ice, AGW in general and my mother-in-law.
Toggle Commented Jun 1, 2017 on PIOMAS May 2017 at Arctic Sea Ice
Let me first make clear that I'm not saying that I think that an exponential or linear extrapolation of PIOMAS volume data is correct and that the Arctic will be ice-free for all practical purposes by 2022. There will indeed be a refuge of ice that might be hard to melt. What I'm taking issue with here, is your statement: If the PIOMAS were reliable, it should produce a regression similar to that of the Area, which I consider Area to be the most reliable metric. If one long-term metric goes down much faster than the other, as is the case with volume vs area, by definition regressions or extrapolations cannot be equal. It also doesn't mean that one is better than the other. Just as the Arctic might not go sea ice-free by 2022, it will highly likely not melt out 'several decades' from now either. And no, average thickness doesn't imply a longer regression period either. Just look at 2012, lowest volume and area/extent minimum on record, but average thickness was similar to other years. You could have just one slab of 100 km2 left, but if its volume is 0.15 km3, that means it's 1.5 metres thick, which would be 0.5 m thicker than the lowest years on the chart. So, I don't find that a good argument for saying that PIOMAS is unreliable. It may be unreliable, but not for the reasons you state.
Toggle Commented May 19, 2017 on PIOMAS May 2017 at Arctic Sea Ice
Wade, can you calculate for me the difference in volume and area between a floe that measures 10 km by 10 km and is 1 metre thick, and a floe that measures 10 km by 10 km and is 10 centimetres thick? My calculator says 100 km2 and 0.1 km3 for floe 1 and 100 km2 and 0.01 km3 for floe 2. So, area stays the same, but volume differs by one order of magnitude. Does that perhaps explain the difference in regression? Or, as Peter Wadhams said 10 years ago: "In the end, it will just melt away quite suddenly."
Toggle Commented May 19, 2017 on PIOMAS May 2017 at Arctic Sea Ice
I plan to find out what happened in 2010 and come up with a theory./blockquote> Check out the Dosbat blog. Chris Reynolds wrote at length about 2010 wrt PIOMAS.
Toggle Commented May 6, 2017 on PIOMAS May 2017 at Arctic Sea Ice
Wade, could you stay somewhat on-topic (PIOMAS and conditions in the Arctic right now) or else go to the Arctic Sea Ice Forum?
Toggle Commented May 5, 2017 on PIOMAS May 2017 at Arctic Sea Ice
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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: It's no surprise 2017 is still lowest on record, according to the PIOMAS model. If during the last... Continue reading
Posted May 4, 2017 at Arctic Sea Ice
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Elisee, first of all, your brush is too broad. This isn't some homogeneous organisation where image can be controlled through hierarchical systems of decision-making. Even though they are bound by a shared concern about the potential consequences of Arctic sea ice loss (and AGW in general), the visitors of this blog and the Arctic Sea Ice Forum are as diverse as can be. Some are alarmist, others are conservative, and so on. Secondly, climate risk deniers who are only interested in deceiving their fellow human beings, will always be able to find some exaggerated quote by some guy. I mean, over 10 years ago some ex-scientist said that there would come a time when British children will never see snow again. This meme is trotted out every winter, and projected onto the entire scientific community and the IPCC. If we are going to worry about that, we might as well stop talking (which is the whole idea, of course). Let them do the lying and misleading, while we each individually try to analyse and speculate about Arctic sea ice loss as honestly as we can. And let the reader judge for him/herself how trustworthy, credible, interesting it is what he/she reads on this blog and the forum. And last but not least, what you're engaging in here, is pure concern trolling. And if there's something I dislike more than climate risk denial, it's that. By your own logic you are providing fodder to climate risk deniers ("one guy tried to warn the stupid alarmist watermelons, but noooo, they wouldn't listen and announced the end of the world in every single sentence they wrote"). So don't do it again and take your concerns elsewhere. Thanks.
Toggle Commented Apr 11, 2017 on PIOMAS April 2017 at Arctic Sea Ice