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John Christensen
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Hi Neven, I stand by my comment: Dr Andrew Slater is with the NSIDC and has the NSIDC logo on this web page, with no disclaimer that this is unrelated to the NSIDC. The issue of course with the graph not fitting the scale is that it alters the discourse to be around 'off the scale' data, and other blogs and news outlets can pick this up. With his background, Dr Andrew Slater cannot be ignorant of this, which is the intentional piece: I don't see that he rigged the scale, but he decided not to fix the scale, before making the graph available. But I respect this type of comment shouldn't be on your blog, so will go into hiatus, as we enter what may become the worst Arctic sea ice melting season so far. - Never complained about PIOMAS though.. ;-)
Toggle Commented Apr 4, 2016 on Winter analysis addendum at Arctic Sea Ice
Impressive data on the FDD from the NSIDC, thanks Neven! - And what any 1st year student would have learned about manipulative statistical representation: The NSIDC couldn't resist the visual trick of letting the 2015/16 line exit the scale, rather than make the scale fit the lines.. ;-)
Toggle Commented Apr 2, 2016 on Winter analysis addendum at Arctic Sea Ice
Thank you for the link Neven! wayne, I will certainly check out your theory and also it's very enlightening to see more about your background. The NOAA AO index is still positive, but is clearly trending towards moderate negative, so will be very interesting to follow the development.
Toggle Commented Apr 2, 2016 on 2015/2016 Winter analysis at Arctic Sea Ice
A true work of art, thank you Neven! Comparing to the longterm AO index for winter months (See below), it is clear that the four seasons with very positive AO (2006/07, 2011/12, 2013/14, and 2015/16) are outliers and that we have seen reduced sea ice area and extent increases during those winters. Hi wayne, It will be interesting, if we will indeed have a La Nina event this year, but I have not seen any papers linking La Nina to negative AO/clear Arctic skies, so please share if you have references or your own data to support that. Looking at the longer-term AO trends for winter months, it seems like we have a multi-decadal trend, as seen from the averages of NOAA AO data: Period Winter (Nov-Feb) Average (1950-2015) -0,28 Average (1950-1959) -0,50 Average (1956-1965) -0,75 Average (1966-1975) -0,40 Average (1976-1985) -0,54 Average (1986-1995) 0,42 Average (1996-2005) -0,24 Average (2006-2015) -0,05 From the numbers above: 1) Long-term average AO (1950-2015) is negative for the winter season (Nov-Feb), indicating overall tendency for clear skies. 2) Negative AO was most pronounced in the period of 1950-85. 3) 1986-95 indicated a decadal-long shift to positive AO during the main winter months, which generally must have reduced ocean heat loss and therefore limited sea ice growth 4) 1996-2005 saw overall negative AO again, but since 2006 we have seen a jigsaw/non-decided trend for AO during winter months. These longterm shifts are also visible from the NOAA graphic, although it is looking at Jan, Feb, March: http://www.cpc.ncep.noaa.gov/products/precip/CWlink/daily_ao_index/JFM_season_ao_index.shtml
Toggle Commented Apr 1, 2016 on 2015/2016 Winter analysis at Arctic Sea Ice
Neven, Your first AO graph is actually great, as it shows the winters of 2006/07 and 2011/12 starting with very positive AO, and this past winter being as bad as those two for the first months of winter. - Which certainly does not bode well for the coming melt season (If you like the ice to stay that is) It seems to be less important how the AO is behaving in Jan and Feb compared to Nov and Dec. If you had included the cold winter of 2012/13, it would have provided a nice contrast to those other years.
Toggle Commented Mar 31, 2016 on 2015/2016 Winter analysis at Arctic Sea Ice
Hi Neven, Thank you very much for sharing this. I was trying to consolidate your numbers with the monthly values from my data from NOAA, which seem to be slightly different: Winter Nov Dec Jan Feb 2006/07 0,521 2,282 2,034 -1,307 2007/08 -0,519 0,821 0,819 0,938 2008/09 0,092 0,648 0,8 -0,672 2009/10 0,459 -3,413 -2,587 -4,266 2010/11 -0,376 -2,631 -1,683 1,575 2011/12 1,459 2,221 -0,22 -0,036 2012/13 -0,111 -1,749 -0,61 -1,007 2013/14 2,029 1,475 -0,969 0,044 2014/15 -0,53 0,413 1,092 1,043 2015/16 1,95 1,444 -1,445 -0,023 What is noticeable from these numbers: 1) The winter of 2006/07 saw positive AO in Nov, Dec, and Jan, which seems to work a bit like melt ponds in the early spring: If the ocean does not loose heat in early winter months, ice extent tends to stay very low. And this winter had exceptionally low ice extent. 3) The 2009/10 winter had great (AO) conditions for ice growth after a slow start 4) The winter of 2011/12 also saw positive AO in early winter months, setting the stage for the summer of 2012. 5) The winter of 2012/13 on the contrary saw lots of clear skies and significant ice growth causing lots of 'recovery' discussion at the time. 6) The three latest winter seasons were not great from a weather perspective with positive AO in early months for two of them and just slightly negative AO for the start of the 2014/15 winter. It is clear - and Wikipedia IMO has the best guide to the AO - that this is not the sole factor, but one of the components influencing the environment in which sea ice is created during the Arctic winter.
Toggle Commented Mar 31, 2016 on 2015/2016 Winter analysis at Arctic Sea Ice
Darn, you were right, thanks AIG! What it should have been: - November and December were dominated by positive AO index, which brings more cloudiness and low pressures to the Arctic region, causing reduced ocean heat loss, higher temperatures, and moves the jet stream further north with many storms entering the Arctic seas.
Toggle Commented Mar 31, 2016 on 2015/2016 Winter analysis at Arctic Sea Ice
Hi AIG, No, I was not trying to confuse you, so please let me know what leads to that state of mind. The AO index: https://en.wikipedia.org/wiki/Arctic_oscillation
Toggle Commented Mar 31, 2016 on 2015/2016 Winter analysis at Arctic Sea Ice
Thank you for a great Arctic winter analysis Neven! The only item I was missing was a review of the atmospheric conditions, which certainly seem to have been a factor for the Arctic sea ice this winter: - November and December were dominated by negative AO index, which brings more cloudiness and low pressures to the Arctic region, causing reduced ocean heat loss, higher temperatures, and moves the jet stream further north with many storms entering the Arctic seas. (In contrast, Oct, Nov, and Dec 2012 all had negative AO index, which caused predominantly clear skies, more heat loss and increased sea ice build-up).
Toggle Commented Mar 31, 2016 on 2015/2016 Winter analysis at Arctic Sea Ice
Hi Bill, Yes, the photo is certainly a fake - not just because of the colors - but also because: - The helmets have no horns - There should be barrels of akvavit (Older name for snaps) visible on the boat, as Vikings (Still to this day) going south of equator always bring barrels of akvavit with them. If they cannot drink it all during the journey, they sell the leftovers as 'linie akvavit' in Norway: http://linie.com/
Toggle Commented Mar 30, 2016 on Mad Max 2: The Arctic Warrior at Arctic Sea Ice
I feel my fact-oriented eyes are being opened for the first time, seeing that there is no black or white, and that the black knight could be mocking the other knights for the sheer fun of it. I will leave Dr. Inferno to his business, which I am sure will have no relevance to my future endeavors..
Toggle Commented Mar 27, 2016 on Mad Max 2: The Arctic Warrior at Arctic Sea Ice
OK, OK, Kevin and Neven, but could you then please explain what makes sense in the entry that idunno provided a link for: "This appears very much to be a menu button. Let me explain to you how these work. A menu button is a piece of technology designed to always display a menu when they are clicked on. But if you click on the University of Illinois menu button in the above image no menu appears. Go on, try moving your mouse over it and clicking, it does nothing except making the image larger. Software engineers are not like climate scientists, they have to make sure the computer programs they write work all the time, every time, and so they learn to never make mistakes. So I have to assume that someone at the University of Illinois has deliberately sabotaged the menu button. I wonder why. What could be on the hidden menu? Perhaps the menu contains links to scientist's emails which They don't want made public. Perhaps there is an option to display the real undoctored sea ice data that are being hidden from us. Or perhaps the button is just another one of Lewandowsky's little traps to try and falsely paint us as conspiracy theorists. Yes I can well imagine Stephan Lewandowsky meeting with suited UN figures at the Paris COP21 in a closed meeting room, discussing a demented form of button over taxpayer funded mugs of hot coffee. A button that can be deployed onto websites that will capture not only the imagination of climate skeptics, but also their IP addresses which are subsequently loaded into a database named agenda21. Someone more proficient at being unethical than me should probably try to hack that button and find out what is behind it. If not I sense an FOIA request in the making. *These are actual files I keep in my house, in a large binder. Update: A commenter, now banned, has kindly pointed out that a button in a copied image from a website isn't necessarily going to work when copied onto a blog. While this may potentially explain why the menu button doesn't work, I stand by my comments and the general thrust of my argument remains. I would think the University of Illinois should really put a disclaimer on their website pointing out that buttons will not work when an image is taken. This kind of lack of attention to detail is becoming a hallmark of climate science."
Toggle Commented Mar 27, 2016 on Mad Max 2: The Arctic Warrior at Arctic Sea Ice
And you were right, Neven, not to call the CT NH area max a week ago..
Toggle Commented Mar 27, 2016 on Mad Max 2: The Arctic Warrior at Arctic Sea Ice
Hi Kevin, After the prediction of the next ice age and the bizar comments regarding the CT chart context menu, where the blogger pretends that an embedded picture should work like a web page, I felt no need to read on: "This appears very much to be a menu button. Let me explain to you how these work. A menu button is a piece of technology designed to always display a menu when they are clicked on. But if you click on the University of Illinois menu button in the above image no menu appears. Go on, try moving your mouse over it and clicking, it does nothing except making the image larger." I actually don't think the blogger is very stupid, since at least he/she managed to establish a blog, but the content is certainly stupid.
Toggle Commented Mar 27, 2016 on Mad Max 2: The Arctic Warrior at Arctic Sea Ice
That you for sharing idunno! I honestly had no idea something as outrageously stupid as that blog existed - hilarious!!
Toggle Commented Mar 27, 2016 on Mad Max 2: The Arctic Warrior at Arctic Sea Ice
Hi Neven, Even with the relatively large increase reported today, CT SIA is still $77K below the peak so to me would be surprising, if this could be reached - but let's see..
Toggle Commented Mar 24, 2016 on Mad Max 2: The Arctic Warrior at Arctic Sea Ice
Hi Neven, Not sure which thread to use, but given the drops in Okhotsk and Bering I would think you could safely call the CT NH area max by now.
Toggle Commented Mar 23, 2016 on Global sea ice area record minimum at Arctic Sea Ice
Hi wayne, Again, I am not too well versed in the landfast buoy measurements, but the jagged temperature chart to me seems to indicate the maximum and minimum temperatures within the 24 hour period at different heights; for the water, the ice, and the air. Still, it seems incredible that the water under the ice should reach -5C in the night and then about -1,8C in the daytime, while the difference in 10 degree in air temps between night and day are reasonable against the weather forecast. Rob, I agree that the temperatures across the Arctic Ocean have been significantly higher this year, but comparing the mass balance buoy air temps of this year to prior years, (Jim's links above) the difference does not seem quite as significant for this place, which is why I was suggesting that part of the reason could be warmer ocean water, causing later and slower freeze.
Toggle Commented Mar 22, 2016 on PIOMAS March 2016 at Arctic Sea Ice
Hi wayne, You may have been tricked like me at first; the temperature is around 0F, not 0C..
Toggle Commented Mar 21, 2016 on PIOMAS March 2016 at Arctic Sea Ice
Hi Rob and Jim, Thank you very much for the additional data on the landfast ice buoys in Barrow! I agree from the data that the ice thickness has increased very slowly this year compared to prior years (since 2010). It seems a bit odd, as the air temperature readings for 2016 have been centered around -20C as for prior years, but maybe the water was warmer initially, or the underlying water is still warmer, so is it possible to compare the water temperatures from the different years?
Toggle Commented Mar 21, 2016 on PIOMAS March 2016 at Arctic Sea Ice
Thanks for sharing Rob! The ice in Beaufort seems to be underestimated given the temperatures of -20C to -30C in the area, but let's see: Spring is coming, and ice of 2m or less seems to typically melt away entirely, so we will know no later than by September.
Toggle Commented Mar 21, 2016 on PIOMAS March 2016 at Arctic Sea Ice
And just to clarify: I made the mistake of mixing coastal ice with landfast ice in my first remark above to NeilT, as I believe others did as well. Evidently it would not be reasonable to compare the 3-4 meters coastal ice with the 3/4 meter landfast ice there.
Toggle Commented Mar 18, 2016 on PIOMAS March 2016 at Arctic Sea Ice
Remember also that the ice of the fresh water lake in the North West Territories, where the truck fell through was 100-120cm, again due to the ice being steady and therefore growing slowly.
Toggle Commented Mar 18, 2016 on PIOMAS March 2016 at Arctic Sea Ice
Hi Jim, Those buoys are in the open sea, which is different from truly landfast ice buoys, since landfast ice is steady and does not get compacted. If you compare with landfast ice in southern Greenland (Tunulliarfik), the ice was 60cm thick on January 29th and grew to 70cm by March 12th, which shows how slowly non-compacting ice grows. Link in Danish: http://www.dmi.dk/nyheder/arkiv/nyheder-2016/marts/dmi-mod-nord-fastis-og-foehn-i-sydgroenland/ Therefore, with this type of ice, the difference between a cold and a warm winter is measured in cm's and not m's, and without more data it is difficult to tell if 75cm is low for the landfast ice in Barrow.
Toggle Commented Mar 18, 2016 on PIOMAS March 2016 at Arctic Sea Ice
For today, CT SIA overall improved slightly due to the forecasted spreading of ice plus some growth in the Atlantic sector of the Arctic, while Hudson, Baffin, Bering, and Okhotsk have gone down further, but not fully offsetting the increase in Barents and Atlantic central arctic. And then the leads clearly are freezing over again in Beaufort and should be safe at least for another two days, until warm temps reach that area.
Toggle Commented Mar 18, 2016 on Mad Max 2: The Arctic Warrior at Arctic Sea Ice