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Tor Bejnar
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Iceman, You have identified all the vectors I've thought were the possible/probable causes of this slow/minimal melt.
Toggle Commented Sep 7, 2014 on PIOMAS September 2014 at Arctic Sea Ice
From the Healy thread: [quote] Lessons from the recent voyage in the Arctic: Dallas Murphy’s blog post on July 1, 2014: http://arcticspring.org/dispatches/closing-circle]http://arcticspring.org/dispatches/closing-circle ... "Then it snowed, barely an inch. Hitherto, no one expected that a slight late-season snowfall could raise the albedo high enough to forestall the formation of melt ponds. So we learned considerable new lessons about the penetration of light through the pack ice before the onset of melt ponds." [end quote] If there was a late snow across the Central Arctic Basin, this could explain the lack of melt ponds. If June PIOMAS for the CAB shows a lack of thinning, this may be the cause. On the other hand, if the CAB lost a lot of thickness in June, I presume this would be largely bottom melt from an apparently warmer sea.
Toggle Commented Jul 6, 2014 on ASI 2014 update 4: high times at Arctic Sea Ice
http://www.hpc.ncep.noaa.gov/qpf/97ep48iwbg_fill.gif Yes, looking hopeful for northern California next weekend!
I've been reading only Neven's posts for months (rarely any comments, and haven't visited the Forum since about the ASIE minimum), and thought to drop in to say hello. Two images stand out to my mind. 1) The Central Arctic Basin (CAB) sea ice may respond more slowly to global warming than do the surrounding basins. (Chris and others write on this.) and 2) I expect the next El Nino year (or the northern summer following) will torch a lot of Arctic ice! (I came to understand sometime last year that as the Earth surface warms, the threshold for an El Nino goes up, and wonder if it will get harder for an El Nino to form. But I know I don't know what I'm talking about.) I too was surprised by the slowed down melt, but given that it happened, I'm not too surprised by the fairly robust freezing.
Toggle Commented Jan 11, 2014 on PIOMAS January 2014 at Arctic Sea Ice
What the consequences was of bits of open water in the high Arctic (e.g., north of 80N). As Arctic surface water with ice cover is about -1.7C, does the open water in leads and small polynyas cool the lowest two meters of air (thus the very low DMI temps)? Recent years have had slightly lower DMI high Arctic summer surface temps than the long-term average. Might bits of open water cause this (or at least influence this)? This year has much more highest Arctic open water, so is this why DMI temps have plummeted? I understand the heat transfer between the Arctic surface (all Earth surface, actually) and (ultimately) outer space is happening all year 'round, only being offset by solar gain during the day (especially the long Arctic 'day' we call summer). How does this support or conflict with the idea in my first paragraph?
Toggle Commented Aug 18, 2013 on ASI 2013 update 7: cold and cloudy at Arctic Sea Ice
I had no problem having to use Google Translate (seems better than Bing, at least from French to English) to understand Gerhard's first posts. It reminds me of some challenges posed by non-English speakers who care passionately about Arctic ice whom we hear from occasionally. I even figured out some words that didn't translate (Neven's "Volumdaten PIOMAS" = PIOMAS volume data). The use of abbreviations not defined in a post or in a recently preceding post, however, make it really tough for newbies and others. (And when an abbreviation is used that appears technical but isn't included in the "Glossary … for newbies and others" on the Arctic Sea Ice Forum nor referenced/defined earlier in the thread, I wonder if the author knows they are writing gibberish, including use of texting shorthand.) Sorry about getting on my soap box.
Even as I expected the PIOMAS volume and Polar Science Center thickness to be less than they are, the PICT thickness is what I expected. If PICT is "right" and PIOMAS is "off", then my gut sense of "the right ordering of the universe" is not consistent!
Toggle Commented Aug 3, 2013 on PIOMAS August 2013 at Arctic Sea Ice
My guess for NSIDC Arctic sea ice extent September 2013 average is increased from 3.6 (previous guess) to 3.75 million km2. (Curiously, this keeps me in the same bin on the ASIF vote opportunity that ended 10 or so days ago. I didn't peek before my calculations, honest!) This projection is largely based on three HYCOM thickness maps: July 29, 2012 & 2013 and September 15, 2012. I compared the 2012 maps to see what melted (or compacted) between late July and mid-September and projected similar changes onto the 2013 map. The Beaufort-Chukchi-East Siberian side of the Central Arctic in 2012 had much “2” to “3.5” meter thick ice melting (or moving toward Greenland); I do not expect a repeat. As I have no electronic graphic manipulation software or skill, I cannot accurately determine the extent I’ve drawn on a printout of the late-July 2013 map (talk about crude science!) I took my HYCOM projection (~4% increase) and increased the NSIDC 2012 September extent average by the same factor. [The quoted HYCOM thicknesses are because that is what the graphic indicated, not what was really there at the time.] I still expect ASI volume and maybe area to have new minimum records this year, but I expect icy rubble will remain dense enough to cause NSIDC extent to not enter record territory. As many a fellow ASI watcher has written, the weather will be significant in determining if new records are set or not. Even as I remain pessimistic about Arctic ice survival, I realize more clearly this year that my understanding of ice dynamics and influences are significantly deficient to qualify me to say much of anything in regards to Arctic sea ice. That said, I grow increasingly appreciative of posters here with significant graphics expertise, and I participate as I can.
Ask a couple of unrelated elders.
Toggle Commented Jul 22, 2013 on The Naming of Arctic Cyclones at Arctic Sea Ice
I meant: (I wonder what "neven" means IN some Arctic region language!)
Toggle Commented Jul 22, 2013 on The Naming of Arctic Cyclones at Arctic Sea Ice
First of all, I agree we should consult with Inuit people who may have insight (cultural and experiencial) into this whole process we are proposing. There's nothing like imperialists taking over something of someone else's (in this case, words). That said, I like the idea of using Arctic people's words, especially words that could possibly relate to storms (like, translated, "sharp"). (I wonder what "neven" means is some Arctic region language!) I like there being criteria that, once crossed, the storm gets a name. I worry about too many days at a certain pressure because we will have been talking about it for several days already. Better to give a name to a short-lived storm (to be forgotten) than miss the monster that therefore gets a news-media moniker. I imagine a criterion something like: minimum pressure less than 985 hPa with a forecast of lasting 72 hours at 990 hPa or less. (I'm not a meteorologist, so these numbers are just echos in my head.) I would ask us to trust the likes of Neven or R. Gates to set up (or have an Arctic native person set up for them) an initial list of names. I see no need for A first then B, but am not against it. (I think the West Pacific doesn't name storms in alphabetical order, and draws from multiple languages.) I imagine having a list of 25 or 500 names that slowly gets used over the years. No need to repeat the first storm's name every 5 or 7 (13?) years.
Toggle Commented Jul 22, 2013 on The Naming of Arctic Cyclones at Arctic Sea Ice
I'm so appreciative of the creative thinking and quality work products these and other folks do and make. Our understanding grows because they care.
Toggle Commented Jul 19, 2013 on Ice pack in full at Arctic Sea Ice
mabs quotes Hansen: "...if the forcing is by fossil fuel CO2 the weathering process would remove the excess atmospheric CO2 on a time scale of 104-105 years, well before the ocean is significantly depleted." It took me a moment to figure out that "104-105 years" is 10^4 - 10^5 years, or 'on the order of tens of thousands to hundreds of thousands of years' Richard Alley talks about this geological CO2 control in his 2009 lecture The Biggest Control Knob: http://www.agu.org/meetings/fm09/lectures/lecture_videos/A23A.shtml
No ice bridge formed after the 2006 melting season, per the referenced NASA-led study, so 2007 had 12 months of transport through Nares Strait. Most years (i.e., the average) have about 184 days of blockage. Although Arctic ice loss through the Nares Strait is much less than through Fram Strait, I give some credit to 2007's record ice loss to the unique event of no ice bridge.
Toggle Commented Jul 12, 2013 on Nares Express is ready to leave at Arctic Sea Ice
2013 is following the "new" PICT path that 2010 started, with calculated (on numbers half modeled and half measured) thickness maxing in June - so at least in this one metric, 2013 is "just like" 2010, 2011 and 2012. It is so nice to be able to depend on something being stable!
Toggle Commented Jul 6, 2013 on PIOMAS July 2013 at Arctic Sea Ice
My June guess is 3.6 M km^2 for average September Arctic sea ice extent as calculated by NSIDC. This is a ‘huge’ increase from my May guess of 3.15. The main influences include 1) current poor state of the ice in the eastern Arctic Basin (endless floe edges to erode and melt from; lots of room for compression under an extended high pressure regime) and lots of ice in southern areas that is sure to melt out anyway, 2) Jim Pettit’s graphs showing what previous year’s loss from the current date would yield (no new record for area or extent is projected - I’m guessing a new record anyway - less MYI, more potential, due to fractures, etc., for MYI export through Fram Strait), 3) Mr. Pettit’s table showing Million km2 steps in CT Area, per day-of-year (2009 had the latest ‘cliff’ start in 9 years, and then lost 3M km2 in a record 26 days - a 3M drop in 24 days would catch 2013 up to 2012) [An aside: I’m missing updates of Seke Rob’s ASI Extent M km2 table; I hope and pray he’s OK.]. 4) NSIDC’s graph of Daily Sea Ice Extent Time Series shows no ‘cliff’ yet (but I expect one to start any day - maybe I’m ignoring the evidence?). 2007 had record melt under spectacularly pro-melting & compacting weather. 2012 had record melt under mostly unspectacular weather. 2013 will require spectacularly pro-melting & compacting weather in July-Sept. to make new records, and it may have started (per Neven’s ASI Update 2013 #3); I’m guessing this will happen/continue. However, we could also end the melting season with an Arctic covered in dispersed slush creating a huge extent recovery. Therefore, the range of average NSICD September Arctic sea ice extent I see possible (and not be shocked) is 3.0 to 4.75 (somewhat in line with Paddy’s thinking). In Fufufunknknk’s June 19 at 12:39 experience scale, I’m somewhere about a 3 (passionate) or 2 (occasional amateur statistical models), and started reading climate science 4 or 5 years ago, starting as a skeptical geologist (how could puny man ...), but quickly gained ‘respect’ for (dismay of) our ability to affect Gaia. Safe (and low-C) travels, Neven. But have fun anyway.
Gosh, we in North Florida only have about two weeks per year of 91F maximums. But we also get a couple weeks at 92, a couple at 95 and maybe a week at 100+ (13 weeks worth of 90+ is average, per the statisticians.) :)
3.15 M km^2 NSIDC mean September 2013 extent. (M = million, in case my mother is reading) I visualized a point on the graph Larry Hamilton posted based on the following: Extent will go down as I expect volume and area to continue to decline (despite PIOMAS virtually duplicating recent years in the current season). A lot of rotten ice and slush will be counted as ice. September mean extent will decrease only a little because leads or polynyas north of 80 or 85 N will freeze over quickly once the sun goes down, and there will be more high latitude open water than ever before at minimum extent. (I’m not sure how wide a lead or polynyas needs to be before being counted as water, but I think some will be big enough.) This northern most area will only be ice-free for a brief time; the water will not have much time to absorb solar radiation (nor mix with deeper water) that would delay re-freezing, and the month average will be rather larger than the minimum. September cyclones, however, would speed melting and delay refreezing. The southern areas of the Arctic will continue to melt when the northern most areas start to refreeze, but there won’t be much ice in southern areas. If PIOMAS volume is currently about the same as it was a year ago, and more area is covered by <2 meter thick ice, then >2 meter thick ice needs, on average, to be thicker than last year’s, and most of this (extent-wise) will stay around into another freezing season (whence some of it will be exported out the Fram). I expect average September Arctic ice extent to go below 1 M km^2 about two years after minimum ice area and volume crash below 1 M km^2 and 0.75 M km^3, respectively. Increased methane will cause the Siberian Arctic to melt faster; Mt. Cleveland’s eruption may slow down Canadian Arctic melting that would otherwise melt faster with all the relatively thinly iced leads (re Cracks of Doom). My mom always uses “M” for thousand (from Roman numerals). I hope Espen is using this nomenclature when he guesses “3,014.699 M km2” or, as a European, uses a comma for the decimal point.
I talked to some folks at a party a few weekends ago about Arctic sea ice projections (“Neven's cadre”) vs. models (“the professionals”). My wife twice, in the following few days, berated me for talking about what “nobody is interested.” In polite society, apparantly, climate change is in the same category as sex and religion. (She did allow that the geologist daughter of our host was possibly actually interested.) I regularly post short articles on a bulletin board in the hallway where I work (often from Grist or Climate Progress). The shelf-life of these articles seems to be much shorter than "free kittens" or "subs with free ice tea" flyers. Although it is a science-friendly environment with lots of engineers, biologists and geologists around, there are many outspoken Biblical creationists, too, who believe in "fire next time". Someday soon, I hope, these neighbors of mine (whom I count as friends) will realize that Anthropogenic Global Warming is that fire.
Toggle Commented Apr 16, 2013 on Perception of the Arctic at Arctic Sea Ice
Thin Ice: the inside story of climate science "In recent years climate science has come under increasing attack, so geologist Simon Lamb took his camera to find out what is really going on from his climate science colleagues." Just the trailer is available now at http://thiniceclimate.org/ The full length will be available April 22-24 (NZ time) - Earth Day.
Toggle Commented Apr 11, 2013 on A new round of vids at Arctic Sea Ice
Sorry, Lodger, but I made no reference to, and implied nothing about, what had happened this past winter. I only reflected on the trend associated with the current wind map and forecast for the next few days for "thickest ice" (intending to mean >2 year old ice). In addition, a certain amount of the December 2 eastern bulge that is missing in your March 28 map moved westward to replace ice that is now in the Beaufort Sea. The only thing I wrote that would definitely put crow on my plate (yuck, I'm a vegetarian!) is if the ice just above Greenland and the Canadian Archipelago moves as fast as ice has been moving in the Beaufort Sea. I do appreciate your showing how much multiyear ice (at least 2 years old) north of Fram Strait has been moved this winter. Your map shows that there is now relatively little MYI in the area most likely to be exported during this melting season. As long as the Beaufort Gyre is supported by high pressure over the Arctic Basin, most of the remaining MYI will stay in the Arctic. The "goat's head", in my opinion, has roughly equal chances of getting exported or moving south, then west.
Toggle Commented Apr 5, 2013 on On the move at Arctic Sea Ice
Projected ice movement, per the ARC ice speed & drift maps (on Daily Graphs page) have winds nudging much of the thickest ice westward - toward the Beaufort Sea - over the next 5 days. The recent cracking just north of Greenland and the Canadian Archipelago will allow the ice to actually move. It won't move 1/2 km/hr, but it'll move. There is hardly any fast ice left. (Well, it is now "fast" in a different way.) When I first started watching (several years ago) some of it seemed so robust! No more. This movement trend will lead to less thick ice going out the Fram. It will just melt in the Arctic Ocean over the next few summers. (Plenty of other ice will go south, probably keeping up with the historical volume of export through Fram Strait.)
Toggle Commented Apr 3, 2013 on On the move at Arctic Sea Ice
Another great presentation, Jim! I noticed today that there is not a PIOMAS wikipedia article, although PIOMAS is mentioned in the article "Measurement of sea ice". I imagine someone at the Polar Science Center (PSC) could write one. The article on PSC's website answered all my questions about how the model works.
Toggle Commented Feb 14, 2013 on PIOMAS February 2013 at Arctic Sea Ice
Jim, I like your graph "Arctic Sea Ice Volume - Annual Maximum and Loss, and Ice Remaining at Minimum" because it uses two sets of data to show what is happening. If extended, what do the two curves (Yearly ice max and Yearly ice loss) project for 2013 and beyond. (The curves' formulas would do.) And thanks, Neven, for digging in the trash!
Toggle Commented Feb 9, 2013 on PIOMAS February 2013 at Arctic Sea Ice
Crandles, I'm curious about the Central Arctic Basin - how its sea ice volume growth/shrinking has been changing, per the PIOMAS model. Unless all that ice flushes out Fram Strait or is moved towards Siberia (to melt there), the "last stand" will be in the CAB. Thanks for all your work on this. That quote from Laxon, et. al. (2013) is a reminder that each data system we look at is useful for internal comparison purposes and not as absolutely correct numbers.
Toggle Commented Jan 31, 2013 on PIOMAS January 2013 at Arctic Sea Ice