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Artful Dodger
Oceania
Picking your Pocket with the Invisible Hand.
Recent Activity
"But now I'm 'stuck' with "gotten to the bottom to" (which I would have written "gotten to the bottom of"). Ahhh, saved by my own ego. (Please, somebody, don't leave my post the last one in.)" Not to worry, Tor. Ah jolly old England, where the rules of grammar are as stable as an iceberg, just before it tips... ;^) In this case, I think we would properly convert the prepositional phrase (the "get to the bottom of" part) into a verb phrase. Ergo, "We need to get to the bottom of so much". And remember, the keel of the iceberg is 90% of it's total (pio)mass. So there's a lot of "bottom". :^) Cheers, Lodger
Toggle Commented 13 hours ago on PIOMAS October 2014 at Arctic Sea Ice
Hi Rob, An R of 0.94 (R-Squared of 0.8836) is impressive: this simple model shows that 94% of the variability in September SIE is explained by May snow cover. So then, what are the correlations with all other months? In particular, I'd be interested in Feb snow cover, as this may show a high negative correlation to Sep SIE. The high albedo of snow also means good insulation of the ground during the coldest months. More snow on land, less freeze of permafrost and more water to runoff in Spring. Apologies if you've mentioned this previously, do have a link to the numerical data for NH snow extent? I'd like to muck about with the data a bit. :^) Land change is an important topic for the Arctic. Have you seen this paper, included in IPCC4, WG1, chp 4 :^) Lemke, P., J. Ren, R.B. Alley, I. Allison, J. Carrasco, G. Flato, Y. Fujii, G. Kaser, P. Mote, R.H. Thomas and T. Zhang, 2007: Observations: Changes in Snow, Ice and Frozen Ground. In: Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change [Solomon, S., D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M. Tignor and H.L. Miller (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA. How about including Arctic river outflow? I'd think there would be some auto-correlation with snow extent, since the underlying variable (heat) is captured by melt rate. Maybe there's a way to tease out heat flux? This map of Arctic outflowing river basins shows starkly how important Greenland will be to the future heat budget of the Arctic. 2012 was MOST notable for the widespread (and ominous) melt of the Greenland ice cap (a first since at least 1898), whereas SIE loss was more of the same... Cheers, Lodger
Oh, and Happy 4th of July to all my American cousins! ;^)
Hi Rob. That's a valuable correlation you've uncovered between Spring on-shore snow extent and September sea ice extent. It appears to be part of the larger Arctic-wide albedo flip phenomenon which is driving loss of MYI and indeed Arctic amplification itself. We need to remember that Summer weather is not just an independent variable in the Arctic equation, but also a feed-back effect due in-part to the loss of highly reflective, high-albedo surface area. Coupled with other positive feedbacks (ie: methane release from thawing permafrost), these large-scale changes to the Arctic surface heat budget can CAUSE the weather that we treat as a random variable. When playing dice, the trick is to know when the dice are loaded. That's all we need to decide. Cheers, Lodger
Hi Wipneus, Axel Schweiger (PIOMAS Principle Investigator and current Chair of the Polar Science Center PSC at UWash) acknowledged and thanked you for your contribution in the PIOMAS April 2014 thread. I think that's also worthy of a mention in this MAY PIOMAS THREAD, too. Well Done, Wipneus! +1 Cheers, Lodger
Toggle Commented May 14, 2014 on PIOMAS May 2014 at Arctic Sea Ice
Hi Werther, Two years on, I believe we now have our answer ;) Cheers! Lodger
Neven wrote: "Which goes to show how incredibly handy it would be to have near real-time melt pond cover fraction data at our disposal, which we could then compare to data from the last 5-6 years." Our blog statistic "Cryosphere today Per Ijis Extent" (CAPIE) summarizes in melt pond fraction in numerical terms. Understand that CT ice area is derived with the ARTISAN sea ice algorithm, which is tuned to classify melt ponds as open water. On the other hand ( or denominator ;), IJIS extent uses an algorithm which classifies melt ponds as sea ice. Thus CAPIE also includes a measure of the total fraction of melt ponds. Indeed, blog all-star Wipneus may be ideally situated to create the exact metric we'd be interested in seeing. With his access to daily IJIS AMSR2 data, by processing the data twice (once with each alternative algorithm), we would see JUST the melt pond fraction. And the geographic distribution of those melt ponds could be plotted on Wipneus' signature graphs and animations. :^) Voor niets gaat de zon op! Cheers, Lodger
Toggle Commented Apr 25, 2014 on More on melt ponds at Arctic Sea Ice
Hi folks, Toward the end of the melt season, melt ponds cover up to 50% of the sea ice area, decreasing the value of the surface albedo by up to 20%. Total melt is proportional to total solar energy absorbed, which is the time integral of sea ice albedo. Hence, earlier melt ponds, more melt. Things aren't just black and white, not in the Arctic, and not with our energy choices. It's time for "Less Denial, More Action" by reducing our reliance on fossil fools. Cheers, Lodger
Toggle Commented Apr 25, 2014 on More on melt ponds at Arctic Sea Ice
As an aside to the topic of the Transpolar Drift Stream, the Beaufort Gyre is known to complete one revolution in approx. 3-7 years, depending on the distance from the center of rotation. I have a geologist friend who tells a 2nd-hand story of researchers stationed at the US Navy Arctic Research Lab in Barrow, AK during WW2. The story goes that they abandoned a vehicle on the ice during a particularly bad bout of weather, and when it cleared the vehicle was gone. But that's not the end of the story. After having to explain how they lost the vehicle, and going through the trouble of getting a replacement in Northern Alaska, two years later the vehicle came back! Still sitting on the ice as if it had never moved. Now personally, I think the story is apocryphal (as are many stories of life in the North), but it sure makes for a great story about the Beaufort Gyre! :^) Cheers, Lodger
Toggle Commented Apr 14, 2014 on Research for a novel at Arctic Sea Ice
To our 1st-time Arctic Author: The first surface ship approached the North pole during the Fram Expedition of 1893-96. Norwegian explorer (Viking?!) Fridtjof Nansen deliberately froze his ship, the Fram, into the pack ice on the Siberian side, with the intention of using the Transpolar Drift Stream to cross the North pole. After 18 months of slow progress, Nansen left the ship by dogteam and made for the pole. He reached 86°13.6′N before a long retreat over ice and water to Franz Josef Land. Meanwhile the Fram continued to drift westward, finally emerging in the North Atlantic Ocean. In Feb 1896, the New York Times ran a story claiming that Nansen had reached the pole and found land there. Perhaps there is something to work on there. Click this image for more: Best of luck with your research! Cheers, Lodger
Toggle Commented Apr 14, 2014 on Research for a novel at Arctic Sea Ice
It appears typepad has changed its sign-in procedure, got a warning of some security hole. No, Typepad has updated their Open-SSL package, to squash the "Heartbleed" bug. So, it's time to change your Typepad password, and any other service where you've used the same username / pwd combination as you use here. Cheers, Lodger
Toggle Commented Apr 14, 2014 on Research for a novel at Arctic Sea Ice
Neven wrote: | April 02, 2014 at 21:55 "I wrote about it two years ago: New Data, Melt Ponds on Arctic Sea Ice." Hi Neven, Happy Spring to you, old friend! Just a quick note that the blog link to this paper is now stale: (here's a new one) Rösel, A., Kaleschke, L., & Birnbaum, G. (2012). Melt ponds on Arctic sea ice determined from MODIS satellite data using an artificial neural network. The cryosphere, 6(2), 431-446. Cheers, and have fun! Lodger
Toggle Commented Apr 3, 2014 on Forecast me not at Arctic Sea Ice
Welcome noiv! Are you this "noiv"? http://www.youtube.com/user/noiv Cheers, Lodger
Toggle Commented Aug 23, 2013 on Hole at Arctic Sea Ice
Neven wrote July 24, 2010 at 21:51 I can't imagine real holes forming in the centre of the ice pack. With all that mobile ice, wouldn't the holes just be filled up by other floes, irrespective of where the winds are coming from? It could only happen if, around this phase of the melting season, winds stop blowing for a week or so, and warm currents, sunshine and air do their thing. But I'm sure that's contradictory, meteorologically speaking. It would look amazing though. Why yes. Yes, it does. ;^) My how the world has changed in just 3 short years! Cheers, Lodger
Rob Dekker wrote August 13, 2013 at 07:40 Do you have a reference to where you obtained your assertion, or if you based in on physics alone, can you give the calculations you used ? Hi Rob, This classic paper on the topic of Ekman transport introduced the physics nearly 50 years ago: Hunkins, K. (1966, August). Ekman drift currents in the Arctic Ocean. In Deep Sea Research and Oceanographic Abstracts (Vol. 13, No. 4, pp. 607-620). Elsevier. Abstract: Current observations from a drifting ice floe in the central Arctic Ocean give clear evidence of a clockwise spiral structure in the upper layers. The data for steady conditions show a boundary layer just beneath the ice and an Ekman spiral layer below it. The depth of frictional influence is 18 m for winds of 4 m/sec. This is apparently the first detailed confirmation of the Ekman spiral in deep waters. Hope this helps, and your local resources allow you access to the full paper. If not, there's a reasonably complete description of the math at Wikipedia. Cheers, Lodger
Toggle Commented Aug 13, 2013 on Third storm at Arctic Sea Ice
The stone age didn't end because the world ran out of stone, and the age of denial won't end because the world runs out of stupidity. It will end when people are too busy dealing with the consequences of climate change (or burying their dead).
Since the storms are all running together, may as well mix metaphors, too :^) "I'll huff and I'll puff, and I'll blow your bear house down!" -- Last GASP2013
Toggle Commented Aug 8, 2013 on Third storm at Arctic Sea Ice
Hi Neven, One other chart might be significant for this cyclone: the 300 mb Jet Stream GFS Analysis for 12Z 7 Aug 2013. Recall that one of the significant factors converging to create GAC2012 was an assist to rotation at the mid level. Since this third storm will likely determine the final SIE, I hereby christen it GASP2013 :^)
Toggle Commented Aug 7, 2013 on Third storm at Arctic Sea Ice
Recall that not a single prediction submitted to the 2012 SIO was below the actual September NSIDC SIE extent. I believe that's because SIE is a poor proxy for the true state of the ice pack. The people who predict zero SIE are not wrong, they're just early: Prof. Peter Wadhams said in Sep 2012: "This collapse, I predicted would occur in 2015-16 at which time the summer Arctic (August to September) would become ice-free. The final collapse towards that state is now happening and will probably be complete by those dates." It's very possible however that a prediction of 6.0 is wrong, in the sense that it may never happen again (say, in the next 1,000 years?) Even with the most optimistic linear model of sea ice decline, there's a best a 50/50 chance of ever seen that level again due to natural variability. Big volcano? Better come soon. But how likely is that? Cheers, Lodger
Rob Dekker wrote: July 11, 2013 at 08:45 Why would the height of the atmospheric pressure zones, especially over the Arctic, go up if the gradient between the NH cells fades? Hi Rob, I think the increased height of the troposphere is a direct consequence of more water vapour in the atmosphere due to a warmer earth, rather than the gradient between circulation cells. Wikipee says: As a rule, the "cells" of Earth's atmosphere shift polewards in warmer climates (e.g. interglacials compared to glacials So it seems the Hadley and Ferrel cells themselves are crowding the Polar cell, raising the height of the atmosphere in the Arctic. Or more exactly pushing the Polar cell further to the North. However, as the jet stream weakens, one would also expect the loss of this natural barrier between cells to raise the average height of the polar cells. Have you seen the polar jet stream this week? It's running from 70N to 83N in the CAA, and 75N to 85N over the Laptev sea right now (00z 11 Jul 2013). Highly unusual, and very far North. Cheers, Lodger
Toggle Commented Jul 11, 2013 on So, how slow was this start? at Arctic Sea Ice
Hi A-Team, Peter Ellis is right about the processes of growth for MYI. Once sea ice is about 2 m thick, it is in thermal equilibrium between heat loss to the atmosphere above and heat gain from the ocean below. This particular ice floe was specifically chosen by Healy or Louis St. Laurent as the largest, thickest floe they could find in the target area (I haven't looked to see which ship deployed this buoy). That's so the floe survives as long as possible. It's not a random sample of the sea ice in the area. It's the thickest ice still remaining. The slabbing and thickening likely just happened years before the buoy was implanted. Don't expect average sea ice data from the buoy, but it does give us exactly what we need. That is, how is the thickest MYI surviving? -- Cheers, Lodger
Toggle Commented Apr 23, 2013 on Perception of the Arctic at Arctic Sea Ice
Lillybrown wrote | April 19, 2013 at 09:21 "So when the arctic warms enough to weaken or extinguish the jet stream (can that happen?)" Hi Lilly, Polar night jet "The polar-night jet stream forms only during the winter months at around 60° latitude, but at a greater height than the polar jet, of about 80,000 feet (24,000 m). During these dark months the air high over the poles becomes much colder than the air over the equator. This difference in temperature gives rise to extreme air pressure differences in the stratosphere, which, when combined with the Coriolis effect, create the polar night jets, racing eastward at an altitude of about 30 miles (48 km). Inside the polar night jet is the polar vortex. The warmer air can only move along the edge of the polar vortex, but not enter it. Within the vortex, the cold polar air becomes cooler and cooler with neither warmer air from lower latitudes nor energy from the sun during the polar night." So this is what's happening now. The polar night jet breaks down, letting the cold out and the warm in. When the reserves of cold diminish, there are only weak temperature differences to drive this jet. I see a more pressing issue for you on the BC coast. How is the pine bark beetle infestation there? It seems a much more immediate threat to the way of life for a lumber town. Remember, the expansion of the tropics and temperate zones is a direct impact of climate change, and is driving the succession of temperate rainforest woodlands toward grasslands. You may get more traction with locals by discussing this issue. Don't expect them to like the answers. It's much easier to like a lie than hear the truth. Welcome to the blog. ;^) -- Cheers, Lodger
Toggle Commented Apr 19, 2013 on Perception of the Arctic at Arctic Sea Ice
Furthermore, what makes you think the group of people that set out this plan 50 years ago to remove the Arctic ice cap will LET you restore it? Remember, "Corporations are people my friend". Cheers, Lodger
Toggle Commented Apr 16, 2013 on PIOMAS April 2013 - extra update at Arctic Sea Ice
Again, what happens in the Arctic does not stay in the Arctic. The loss of the sea ice is the first domino to fall, but after that events will accelerate and become unstoppable: The Gulf Stream moves North Meridional heat transport increases polar jet stream stagnates droughts and floods become recurrent agriculture crashes Greenland melting accelerates Sea level rise accelerates Entire Nations fail destabilizing Regions Climate refugees spawn military conflict Corporations challenge Governments Breakdown of Government, fragmentation into regional fiefdoms and zones of anarchy Basically the worst parts of the bible, if you believe in that kind of stuff. If not, think of the 1940s x 10. An order of magnitude worse than WW2. That's what's at stake. Notice that at no point above do Governments move to reduce greenhouse gas emissions or reform land use practices? It's up to us, because they respond only to their masters, the monied special interests. 00 > \_ Here's more from Gwynne Dyer Dec 9, 2012: Coasting toward climate change disaster Regards, Lodger
Toggle Commented Apr 16, 2013 on Perception of the Arctic at Arctic Sea Ice
Nimbus I satellite data from September 1963 has been retrieved, and is now available in a newly published paper (freely available PDF is here). Meier, W. N., D. Gallaher, and G. G. Campbell. "New estimates of Arctic and Antarctic sea ice extent during September 1964 from recovered Nimbus I satellite imagery." The Cryosphere Discuss 7 (2013): 35-53. New results are provided for end of Summer Arctic SIE (about the same as 1979-2000), and end of Winter Antarctic SIE (significantly higher than 1979-2000). Cheers, Lodger