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Neven, we are never too old to learn. Here is a quick and dirty translation (no attempt at rhyming): A small low in Beaufort got all attention this year, ’cause strong winds blew swells towards the coast. On their way, they broke remaining floes, as if they were just fragile cakes. Now Barrow is battered, and I’m anxious/excited.
Toggle Commented 2 days ago on Arm's race (and a storm) at Arctic Sea Ice
Neven, thanks! Again you have done a splendid job summarizing this precarious situation. This morning on the train to work, I couldn't help write a little poem about it (in Danish unfortunately): Et lille lavtryk Beaufort fik al opmærksomhed i år fordi der blæst’ en vældig vind og dønninger på kysten ind. På vejen knak de sidste flager som var de sprøde kager. Nu Banker Barrow blot i brændingen, Mens jeg tydeligt mærker spændingen.
Toggle Commented 2 days ago on Arm's race (and a storm) at Arctic Sea Ice
Espen, at the moment I see 183 more or less meaningless contributions to that thread in Ingeniøren. I am as disappointed as you are, that this story has not been picked up by any news media in our country. On the other hand, when I see how the Washington Post treated this story, I came to think of a new term: journalistic reticence.
Toggle Commented 7 days ago on Jakobshavn record retreat at Arctic Sea Ice
Hi Espen, because Neven says that this blog is for news and the forum is for discussion. Details of Substage 5e some 125 thousand years ago on a remote tropical island can hardly be called news these days... Cheers P
Toggle Commented 7 days ago on Jakobshavn record retreat at Arctic Sea Ice
Marcel, I just got through the Hansen et al. draft, and I am pretty sure they did not consider the ice fall mechanism. During my reading of the manuscript, I discovered that you had overlooked the contribution from one retrograde glacier basin in Antarctica. Apparently the Cook glacier may over time contribute about half of the SLR of the Totten glacier (possibly 0.5 m in your numbers). Hansen et al. also reminded me that continental droughts may soon contribute a few decimeters to the overall SLR picture, which brings the overall total closer to 13 m. However, when I started to dig into the underlying references, they suddenly opened up a can of worms. On several lines of evidence, I do not concur with the authors. When it comes to the “chevron ridges and wave run-up deposits on Bahamas” (Hearty et al. (1998), I respectfully have to disagree. The interpretation of these morphological units is utter nonsense. Nowhere are these aeolian parabolic features made by waves, and the (apparently wave washed) 2000 t boulders are not even described in the paper. This thread is however not the right place for a discussion like that, so I will eventually have to move the discussion to this thread: http://forum.arctic-sea-ice.net/index.php/topic,1327.0.html in due course.
Toggle Commented 7 days ago on Jakobshavn record retreat at Arctic Sea Ice
Tor, You are absolutely right. The white "spots" in the lakes are remnants of last year's lake ice. So, it is not the lake bed you are seeing, but the signature of a perennial lake on the ice sheet surface indicating either a large depression or a slow glacier under neath.
Toggle Commented Aug 22, 2015 on Lakes on a glacier at Arctic Sea Ice
Even Danish media have now picked up this story: see: http://ing.dk/blog/verdens-varmeste-maaned-178151 About 15 cm down, there is a link to this thread. Lookout for the keyword "Jakobshavn" and please ignore the discussion (mainly in Danish).
Toggle Commented Aug 21, 2015 on Jakobshavn record retreat at Arctic Sea Ice
Chris Mooning I think you are kidding… James Balog’s 2009 TED-talk video here: https://www.youtube.com/watch?v=DjeIpjhAqsM shows around minute 16:00 some time lapse footage of the ice fall in the background. I recall having seen even more dramatic and more recent time lapse photos of the ice fall on the northern shore of the Southern Branch. If someone could just point me to such footage off the beaten track, that would extremely helpful.
Toggle Commented Aug 21, 2015 on Jakobshavn record retreat at Arctic Sea Ice
Marcel_g Sorry to have confused you with a well-known fracking formation in the US underground. Again, I largely concur with your reflections on the Rignot et al. papers over the years. I have myself been over that same exercise of adding numbers from snow cover sublimation, sea ice melt, shelf-ice disintegration, ice-stream calving, mountain glaciers melting, permafrost thawing etc. It is a lot of fun doing the maths, but not really applicable in a public context. Maybe Rignot et al. tried to see the disintegration as a 2-dimensional problem. In reality – as shown by the recent disintegration of the Southern Branch of the Jakobshavn Isbræ – there are actually 4 dimensions to the problem: 1) Retreat of the calving front due to warmer oceans 2) Lowering of the ice-stream surface due to this retreat 3) Ice fall from surrounding plateaux due to less buttressing 4) Global sea level rise over time due to 1-3 above. Please remember that there is always a grounding line available somewhere under the ice-sheet. I still reckon, that since both Dansgaard-Oescher- and Heinrich events happened in the Northern Hemisphere concurrently, we have to combine all our knowledge about catastrophic palaeo-events with the most recent observations from the most likely source of natural variability. Disregarding for a moment your timing estimates, I came up with following cumulative SLR: GrIS............4.5 m GrIs Add........2.0 m WAIS------------4.2 m Totten..........1.0 m Mountain Gl. ..0.3 m Ocean warm....0.3 m Total.........-.12.3 m It's not that far off my initial estimate of 14 m. What the heck, I consider this a rounding error of no practical importance on the time scales we consider here.
Toggle Commented Aug 21, 2015 on Jakobshavn record retreat at Arctic Sea Ice
Marcellus, wellcome to the blog. I trust you are one of those "true glaciologists" advertised for. I generally concur with your reasoning. My main point was that Greenland melt would have to come first in order to lift up the WAIS. I must admit, that I have not yet finished reading the Hansen et al. draft, so I honestly don't know, whether they have included this ice-fall mechanism or not. Nevertheless, it is good to have you onboard. Please provide reflections and observations at your convenience. Cheers P
Toggle Commented Aug 20, 2015 on Jakobshavn record retreat at Arctic Sea Ice
Kris, Previous footage from the Jakobshavn calving front retreat were quite scary. In the old days, the ice stream carried Inland Ice from the centre of Greenland (now colloquially called the “Southern Branch”) towards the coast, which helped to keep the ice level high near the coast. After the initial retreat of the ice front some years ago, it was quite obvious that a new “Ice-Fall” developed on the northern shore of the newly developed “Southern Ice-fjord”. It is ridiculous to discuss the detailed forth and back of the current calving front of the Southern ice-stream on a daily, weekly or even monthly basis. Fact is that year to year changes since the incursion of Atlantic warm salty waters across the sill at the entrance of the Jakobshavn Ice-fjord has gone only one way: DOWN. Looking ahead some few years, we may foresee a retreat of the calving front Eastwards some 40 km from the current setting. This will open up 2x40 km’s of ice-falls on the northern and southern side of the Southern Branch. I am fully aware that Ice-streams have one kind of flow properties. However, Ice-falls are a completely different kettle-of-fish. Ice-falls may actually be compared with solid precipitation, since examples show that ice falls do not need physical connection to carry on moving massive amounts of glacier ice downhill from a plateau to a fjord. Getting the new landscape details correct is essential. Getting the true glaciologist onboard is even more important. My bet is that the Greenland Ice-sheet will provide the first 7m of sea level rise through the ice-fall mechanism. Later on , we should expect to see the West Antarctic contribute another 7m of sea level rise due to essentially the same Ice-fall mechanism.
Toggle Commented Aug 19, 2015 on Jakobshavn record retreat at Arctic Sea Ice
More wood on the fire: New Japanese study is out (abstract only): http://www.sciencedirect.com/science/article/pii/S1873965215300050 Using a high resolution (60 km grid) global model, observed SSTs and a robust SST ensemble for the future under an A1B scenario, they find that enhanced advection of moisture to the Arctic is going to increase even further. It says in the abstract, that: “The increases in PAVE, SDII, and R5d can be partly attributed to an increase in water vapor associated with increasing temperatures, and to an increase in the horizontal transport of water vapor from low to high latitudes associated with transient eddies.” As is clear by now, the early autumns (Aug-Oct) in the Arctic will be warmer and warmer and if the tropics at the same time get colder and colder due to more intense tropical cyclones, we may soon see the equable climate conditions unfold.
Toggle Commented Aug 16, 2015 on A wetter and warmer Arctic at Arctic Sea Ice
Neven, Please avoid the "Like"-button. This is not a vote forum or a beauty contest. It is a deadly serious matter for the whole world. Having Cincinattus around for a short while was thought-provoking, which is good in my mind. Please avoid the scape-goat'ism, which has been sticking out it's grim face in this thread for a while. It is really bad taste to continue ridiculing a guy, whos has been "banned for life" on this site.
Toggle Commented Aug 6, 2015 on PIOMAS August 2015 at Arctic Sea Ice
Well spoken Sam On the other hand, this move may give the World a new and strong focal point to oppose. One should have thought that Shell had learned something from the Brent Spar affair... Cheers P
Toggle Commented May 14, 2015 on Bill McKibben nails it at Arctic Sea Ice
http://desmogblog.com/lawrence-solomon apparently a source of many delusions...
Toggle Commented Apr 3, 2015 on The Ns are calling the maximum at Arctic Sea Ice
Cincinnatus & navegante Inspired by your negative reactions and your harsh references to the “Arkham Asylum for the Criminally Insane”, I decided to follow your leads and look at both the Eocene Epoch and the concept of “Living Fossils”. What I found was this: Living fossils are quite unique in this world. Several definitions appear, but I liked this one in particular: “A living fossil is an organism that has retained the same form over millions of years, has few or no living relatives, and represents a sole surviving lineage from an epoch long past. Many living fossils alive today have bizarre, eccentric traits that make them seem more like aliens than anything from this world. They have often survived several mass extinctions, and many scientists consider them to be a rare glimpse at how life on Earth was long ago. “ A few examples are: From Botany: Japanese Umbrella Pine ( see http://blogs.ubc.ca/conifersubc/?page_id=66 ) and it’s Eocene amber producing relative: http://en.wikipedia.org/wiki/Sciadopitys Chinese water fir – also known as Dawn redwood (see http://en.wikipedia.org/wiki/Dawn_redwood) is particularly fond of wet environments Gingko Biloba (http://en.wikipedia.org/wiki/Ginkgo_biloba) , which is a living fossil favoring disturbed river side environments Various forms of laurels (see http://en.wikipedia.org/wiki/Lauraceae ) often found in moist locations in isolated stands (also known as Laurel forests http://en.wikipedia.org/wiki/Laurel_forest) From zoology: The Okapi (see http://en.wikipedia.org/wiki/Okapi ) is a rare species living in the tropical rainforests in the Democratic Republic of Congo The Platypus (see http://en.wikipedia.org/wiki/Platypus ) is a SE Australian minority species living in just three watershed in the riverbanks The Quensland Lungfish ( see http://en.wikipedia.org/wiki/Queensland_lungfish ) is yet another species surviving drought and flooding in its own special way Critters and below: Finally, Stromatolites are found in coastal marine environments in NW Australia ( see http://en.wikipedia.org/wiki/Hamelin_Pool_Marine_Nature_Reserve ). Apparently this particular subspecies has survived on earth for about 3.5 billion years building solid calcium carbonate structures during times of trouble. New species also appear from time to time: Birdie Namkheng (see http://forum.arctic-sea-ice.net/index.php/topic,416.msg8891.html#msg8891 ) So, in order to sum up: All these living fossils seem to have survived both the Eocene and the Eemian. They nearly all favor moist climates and they seem to prefer nocturnal activities. They also seem well fitted to exploit all the new opportunities of a near-future equable climate. I was just wondering, whether there would be any similarities between contributors to the ASIB and those “Living Fossils”. Apparently we have all survived in small pockets of existence, we become active during the night, we are generally very old, and – despite spreading our seeds worldwide – our ofsspring seldom takes our civilization to a higher level. May I propose to change the name of the ASIB to: “Asylum of the Living Fossils”
Toggle Commented Apr 3, 2015 on The Ns are calling the maximum at Arctic Sea Ice
Gents & ladies Some have asked about the Barents retreat this year. Is it part of the new pattern? It may be, and I will try to explain why. Oct-Apr The Bering Sea remains open due to a hot North Pacific Nov-Feb Nares and Fram straits remain open – shifting loads of the remaining multi-year sea ice southwards Dec-Mar Extra-tropical cyclones feed on the temperature contrast between ice and Gulf Stream waters in the NW Atlantic and cyclones move persistently towards the Barents Sea - transporting warm and moist air towards the eastern Arctic hemisphere Jan-Mar Snow accumulates in the Arctic – 500-1000 km3 more than in previous years Feb-Apr Arctic sea ice maximum extent fluctuates around a new winter minimum despite total darkness in the Arctic Ocean Mar-May Sublimation of snow catches on despite sub-zero (degC) temperatures all over the Arctic land and ocean areas Apr-Jun Snow starts to melt from the south - eats away the protective snow cover - and forms melt ponds on the flat, young Arctic sea ice May-Jun Early season persistent Arctic cyclones breaks up the fragile Arctic sea ice and stirs the temperature stratification in peripheral seas Jun-Aug Peak insolation melts isolated ice floes and heat up waters in the Central Arctic Ocean, as well as thawing permafrost over the continents Jul-Sep Tropical cyclones delivers dry and warm air high in the atmosphere, which adds to the melting of the Greenland Ice sheet Aug-Oct The temperature contrast between the Arctic and the Tropics is so low that only one (extended) Hadley Cell can exist Sep-Nov Late season persistent Arctic cyclones detoriates remaining ice floes and breaks up late season halocline in the Central Arctic Ocean Oct-Apr Marginal seas may see some sporadic sea ice formation, but the Central Arctic will remain open It may take more than one year to get through this shift to a new seasonal cycle, but open it will be…
Toggle Commented Mar 30, 2015 on The Ns are calling the maximum at Arctic Sea Ice
We have now passed the minimum and some important players have passed a sharp corner. Today, it was announced that the World's largest toy producer has decided to end commercial activities with Shell -mainly after a public (6 million people signed up!) manifestation. Read the full story here: http://www.thelocal.dk/20141009/lego-drops-shell-after-greenpeace-campaign
Yolo - ” If the tar sands are fully exploited it's game over. Terry” c.f. http://forum.arctic-sea-ice.net/index.php/topic,861.msg37848.html#msg37848 Dear Terry No it’s not! The tar sands may eventually become our rescue. Think of a scenario, where the Arctic tundra starts to disintegrate in earnest -full scale - across the Northern Hemisphere. Under those circumstances, it would be wonderful to have a close-by reserve of asphalt at hand. Think about a situation, where greenhouse gases (CO2 in a dry disintegration process and CH4 in a wet disintegrating scenario) are threatening our common survival. Having the World’s largest reserve of asphalt readily at hand would soon become a nice and easy way to cover the surface of the melting tundra before complete destruction takes place. To help refreeze the tundra big scale, we would most likely need a cheap white surface dressing to recover albedo losses (due to vanishing snow cover), In this case, we have a small producer of white stripes in Denmark, who may come in handy at one time (see http://www.luxol.dk/index.php?lang=en). It would be outright stupid, if the Canadians chose to convert their tar sands into liquids and pipe them to the Atlantic coast. The market for fossil oil products would most likely be gone by the time they reach the coast, and they would have lost their biggest opportunity to contribute meaningfully to a “soft landing”. Actually, I think the Canadians have a moral obligation to conserve the tar sands for later use to the benefit of the World’s more vulnerable populations. So, with XL keystone decision just around the corner, and with the minimum of intelligence displayed by our Canadian friends, I think I’m still barely within the limits of this thread…
Mark, you seem to be trawling right now. First you were asking about historical facts. Then you were insinuating that solar and magnetic cycles were driving the whole thing. Now you even revert to questioning the details of an event which took place more than 150 years ago. Why not come back to the present. Give us an estimate of the future based om your apparent knowledge – or please address the future consequences of our current misbehaviours – such at the dwindling sea ice. When Viddaloo comes up with a diagrame like this: http://forum.arctic-sea-ice.net/index.php?topic=994.msg36817;topicseen#msg36817 it does not make sense to walk your way. Seventeen years from now, you may also face the brutal reality of your children or grandchildren: No more ice at all! No more seasons to enjoy! No more life to sustain. You should be a shame of yourself!
Mark, you seem to have missed some of the discussions taking place last year. The first remark I would like to refer you to is from early August 2013. Back then I alluded to a specific situation, when moist air masses from the Mexican Gulf and the Eastern Pacific converged and rose over Mexico for an extended period of some weeks. http://neven1.typepad.com/blog/2013/07/second-storm.html?cid=6a0133f03a1e37970b01901e9abeaa970b#comment-6a0133f03a1e37970b01901e9abeaa970b The flow of warm moist air aloft could be followed through the first (now obsolete) link. As described in the text, the stream of moist air took a course from the Caribbean to Denmark, where it led to unseasonably warm and moist weather. The second remark stems from later in August 2013, when an “atmospheric river” ran all the way from the Caribbean to the Barents sea. http://neven1.typepad.com/blog/2013/08/third-storm.html?cid=6a0133f03a1e37970b0192ac890f93970d#comment-6a0133f03a1e37970b0192ac890f93970d On that occasion, I tried to do a rough back-of-the-envelope calculation to illustrate the existence of a single temporary Hadley cell circulation at that time. Please have a look at these events and try to explain how you wish to introduce solar cycles or magnetism in this new reality we seem to be facing.
Jai, I admire your stamina during these difficult times. You showed elegantly ( see http://earth.nullschool.net/#2014/05/12/0300Z/wind/isobaric/850hPa/orthographic=-166.96,64.74,560 ), that from the 12 May 2014 (and throughout most of May and June) advection of massive amounts of latent heat (at 850 hPa) started from the Northern Pacific across the Arctic Ocean all the way to Denmark. You also took the time to show us the accompanying surface video from Buoy 10 (see http://obuoy.datatransport.org/monitor#buoy10/movie ). Apart from the wall to wall cloud cover, I also noticed a continuous supply of ice needles from the sky and constant snow drifting on the ice surface. These signs bear witness that condensation took place aloft and surface temperatures were well below 0 C, as also shown by the DMI 80N+ graph. In another thread, I alluded to the unusual dewfall over Denmark during this same time interval (see http://neven1.typepad.com/blog/2014/09/piomas-september-2014.html?cid=6a0133f03a1e37970b01b8d067e45e970c#comment-6a0133f03a1e37970b01b8d067e45e970c ). Apparently this advection of moisture across the North Pole was the main explanation for many of the phenomena observed this summer. Finally, you came up with a fine link to a new Korean study, which clearly shows that extensive cloud cover in May and June is preserving the ice over the summer. The only critical thing is, that apparently the climate models have not yet been able to pick up this idea...
Neven, since you ask.. There may be another explanation, but it is difficult to stick the arguments together, because some of the diagrams I need to explain are hidden in various threads on the Forum. The main story goes like this (details may come later): One diagram showed that in recent years, the volume loss was most conspicuous in Jun, May and possibly Apr. Losses in Jul, Aug & Sep were pretty linear (boring). At the same time we have not seen any melt ponds in recent years, which to some have been a kind of a mystery. 2013 may have an obvious reason (persistent lows), whereas 2014 may require another explanation. The only way to lose extensive amounts of sea ice without forming melt ponds , is – as far as know – sublimation. Could it be that the atmosphere in spring (after spring equinox) is now warming so rapidly (due to build-up of GHGs), that ice and snow has simply started to sublimate instead of melting?. We have seen the most dramatic cryospheric changes in the NH snow cover in May & Jun (without the usual spring floodings). This development is now paralleled by massive losses of sea ice during the same months (without the melt ponds). Once we cross the summer solstice, the atmosphere in the NH starts cooling and consequently we should see the opposite of sublimation (i.e. condensation) taking place large-scale. I myself have been living mostly in mid-latitude climates, and I have been used to this effect (called dewfall which has been most prominent in Aug and Sep) all my life. Suddenly this year in spring and early summer, I have for the first time experienced substantial dewfall in May, Jun & Jul. I was wondering how this came about, but could not find an immediate explanation. (This change came after a winter season, where I also experienced drizzle in a so far unprecedented manner, but that is another story).. However, after reading the thought-provoking paper on the melt vs sublimation process, I came to realize that this change from melting to sublimation large-scale should also have implications for the dewfall (what goes up – must come down). So if this dewfall-effect is not picked up by models, we will not be able to project when the remaining sea ice will be gone. I do realize that dewfall does not really melt any ice, because the heat energy will stay up in the air, whereas the dew will fall onto the ice or the adjacent ocean area (with a temperature close to 0 deg C). The same issue is with drizzle, which is also a way of removing excess moisture from maritime air masses (leaving the heat energy above the clouds), when these air masses are advected over land areas. So to sum up: As long as we don’t measure dewfall, we will not be able to understand what happened with the sea ice this year.
Toggle Commented Sep 11, 2014 on PIOMAS September 2014 at Arctic Sea Ice
Gents ( and remaining ladies…) Sitting here on the Normandy coast with a cold beer helps to clarify your thoughts and systemize your reflections. Experiences from a long list of field experiments in the Arctic puts some of your remarks above into context. Here are my main views: 1) The potential rapidity of melt is a reflection of the ice formation process 2) The mixed bag of current Arctic sea ice qualities precludes any robust statements about a “poof” this year 3) The future may guide us to a more clever risk management approach Ad 1) The Russians have a wonderful word: “Naled” (pronounced naljot! I believe). It is a type of ice which is formed in the middle of winter, when freshwater breaks to the surface. In Greenland, I have seen this type of ice formed in front of a glacier, when late summer melt water eventually emerged from underneath the front and spread out over a lake already covered with ice. The vertical ice crystals were > 0.5 m long and 2-3 cm across – like a white, clear and crisp version of columnar basalt. During the summer “heat” (0-5 C), these columns would tumble down in front of your eyes. In less the a day half a meter of solid ice may disappear, if the formation process is of this type. Ad 2) As A-team has so vividly demonstrated on the Forum, glacier ice at the bottom of the Jakobshavn Isbræ is a mélange of various sorbet types. It is evident that the crystals in this type of glacier ice consist of all kinds of tiny, agile, flexible and scalable pieces. Above this dynamic zone near the bottom of the glacier, you will find clear, cold, crisp and big ice crystals. I believe that x-ray pictures show these to be 2-3 cm across. Thus when you walk down the glacier, your boots will meet melting ice similar to glass in the beginning and then, when you start walking into sorbet ice, the sound from your boots change immediately. Thus the history of deformation of the ice will also make an imprint on the ice quality. Apparently small and big ice crystals melt at the same rate on the surface, so it is not easy (apart from the sound) to say whether you have crossed the line. Ad 3) As time goes by, we will have to await how the Arctic sea ice is formed in the next few years. Some of it will be based on “flash freezing” – leading to amorphous ice - like when a cold katabatic wind comes off the Greenland ice sheet in the autumn. Some of it may be formed from regular “plate ice”, as we have seen in open ocean situations over the years, and some of it may be of the “Naled”-type, if the Greenland ice sheet delivers freshwater on top of already formed sea ice in the middle of the winter. I think I’ll go to the beach now and see the tides come in. Cheers P
Toggle Commented Aug 5, 2014 on Poof, it's gone at Arctic Sea Ice
Bob If you really wish to go OT, why not try something like this: http://www.aqua.dtu.dk/english/News/2014/05/140514_Bluefin_Tuna_caught_hunting_for_mackerel which tells a story of unprecedented bycatches off the East Coast of Greenland in August 2012. On one hand, the story of global tuna fishing is as depressing as the story of whale hunting and sea ice disappearance. On the other hand, this story also gives us a glimpse of hope, that one day in the not so distant future, the last Atlantic bluefin tuna on this planet will be able to swim across the Arctic Ocean and meet up with the last surviving Pacific bluefin tuna, and - who knows - get together for a fresh start...
Toggle Commented May 31, 2014 on Greenland 2013 in review at Arctic Sea Ice