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Steve C
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Presuming the cyclone proves to be intense and persistent, might I suggest the name "GPAC-2013"? For "Great+Persistent Arctic Cyclone of 2013," of course. Further, a nickname of "Cyclone Shelly," in honor of Shell Oil's misadvantures in the arctic, both business and environmental misadventures.
Mignonette writes: "Greenland Sea has less ice area than in 2012, as one of the only places in the Arctic. Does that mean there is less export to Fram Strait? Could be a sign that the Dipole Anomaly is weak?" I don't think it's a reflection on the potency of the dipole anomaly. I don't know of a good day-to-day (or even month-to-month) published measure of transport through the Fram. But I infer rate of transport roughly from the wind fields implied by ECMWF's pressure isobars, and I look at these daily. If there's validity to this eyeballing, I can say that transport through the Fram seemed to be quite brisk over most of the winter, but quite sluggish throughout the spring. There IS a known seasonality to Fram transport (published somewhere and cited somewhere on this blog in the past). Transport is typically fastest in the winter. It would take some days for a dipole anomaly to begin accelerating ice transport through the Fram, I believe.
I think balloon-based geoengineering (with mitigation!!!!) is interesting and worth thinking about. Small balloons have problems of litter, high surface-volume ratio, and more. Thinking big makes more sense to me. Hydrogen diffuses through almost anything, latex, plastic film, even metals. But graphene is impervious, so graphene-coated plastic films could be used. Yeah, we'd want km^2 sized units. At that size, they could have solar cells on top for power to run electrolysis on water either stored or captured from water vapor. You could even power fans to move the things slowly. Paint the top white and the bottom black. It would absorb outgoing IR and transfer it to the air at high altitude. Steer them to the arctic in sommer, the southern hemispher in their summer. And the whole thing could be funded by putting advertising on the underside. Ewww.
John33 Warming of the Mackenzie river outlet area waters is simply NOT from kinetic energy of waters moving via Coriolis forces. AS was already pointed out, you cannot tap the rotational energy of the earth by moving around mass on its surface. Angular momentum of water that moves towards the pole is simply transferred to the angular momentum of the water moving away from the pole. Those movements are ultimately driven by solar heating and wind, not the rotational energy of the earth. In principle, those waters could be warm because of warmer pacific waters moving there -- but sea surface temp data don't support that interpretation well, from what I can glean.
Lewis, You raise some fascinating questions about melt lakes and what happens to the water and the warmth once a moulin forms and the lake drains (at mind-boggling speed). One bit information may inform our thinking about what happens. The mass of ice below the surface is bitterly cold, in the rough ballpark of -20 C. Warmer near the top, and warmer at bedrock level, but mostly very, very cold. Once a given liter of water disappears down a moulin, it either keeps moving fast, or it goes to a stagnant place (cracks, crevices, crevasses with dead-ends) and freezes. If that liter of water freezes before reaching the sea, the heat of fusion transferred to depths of the ice sheet dwarfs the kinetic energy it may have (at least, I'm pretty sure on this). I don't know how much has been discovered about whatever network of persistent drainage channels may persist year after year, but I'd wager that they're essentially all sloping continuously towards the sea. Any dips that could form would form pools after the lake finishes draining that would then freeze solid. None of the above begins to answer the crucial question of what percent of melt lake water finds its way to the sea, and what percent of water fills cracks, crevices, and transfers all its heat to a warming of the ice sheet itself. Looking forward to future decades, it's a crucial question. If the depths of the ice sheet warm quickly from -20 to near 0 C, the whole ice sheet becomes far more plastic/fluid, and sea level rise will accelerate massively. What we need is some research into what actually happens to the water in those melt lakes that form every summer. I can imagine golfball-sized devices put into melt lakes that are designed to have a density of fresh water, that can record when the lake drains and when the device hits sea water. Maybe when hitting sea water it can wake up and transmit the information by radio. A hundred each in a sampling of melt lakes could tell us a lot. Best wishes, Steve C.
Terry, I'm no expert, but maybe I can provide insight. Let's look at ITP-41 profile image at: http://www.whoi.edu/itp/images/itp41dat3.jpg Yes, the plots are in pairs. I think understanding them demands careful attention to the vertical scales. In the two pairs, the top chart has a smaller range of depth -- it's simply a kind of close-up of the layering of the top 200 meters. The one below displays the full-depth profile. So why does 200 meter color on the top chart not match the 200 meter color on the lower? The color scales are different, but you might miss that if you don't pay close attention to the negative signs for temp on the two different scales. It seems they do this so that the color scales can be used to better show the stratification over the different plots. Hope that helps. Steve C.
Toggle Commented Oct 6, 2012 on PIOMAS October 2012 (minimum) at Arctic Sea Ice
Neven, That NOAA ClimateWatch Magazine video has just been uploaded to YouTube, so you can embed it now, if you want to edit your post. http://youtu.be/cQ3QUdIxvxg Fortunately, US Gov't products are public domain, so I shouldn't get in trouble for uploading it to YouTube. Steve C
Toggle Commented Oct 6, 2012 on More vids at Arctic Sea Ice
Donald, Reasonable question. Like most here, I'm just a semi-intelligent, semi-educated amateur. I think the short answer to your question is "yes, but..." Surface evaporation in the arctic will tend to raise surface salinity, sure. Of course, warmer arctic and pacific waters evaporate more, and for every cubic meter of cold air leaving the arctic with moisture, a cubic meter of air enters, typically with more moisture. Still, air leaving the arctic didn't have as much moisture when it was all ice-covered. So you might expect changes of the past few years to yield a net decrease in moisture accumulation (and precipitation) in the arctic. EXCEPT that, as ice has retreated, Atlantic and Pacific have also warmed, yielding more water vapor to the air that enters the arctic (presumably). And thus a net increase of more fresh water to be laid on top of the sea waters. But really, net deposit of more fresh waster is surely overwhelmed by increases in mixing in the arctic. Water temps, counter-intuitively, go UP as you go down in depth, to a max at around 200 meters. Mixing is powerfully enhanced by waters being open (or covered by broken-up ice) instead of vast solid sheets of ice. We've seen some temp/salinity profiles discussed here that show some impressive examples of mixing and/or eddies that can occur right down to that 200 m depth. The paradoxical increase in temp with depth is only possible to maintain because of salinity also increasing with depth. If the salinity gets mixed up, not only do warm waters get mixed at the time/place of mixing events, the breakdown of the salinity gradient allows that warmth to keep convecting up to the surface waters and ice. This enhanced mixing, with breakdown of salinity gradient, is the prime reason why I expect ice re-growth to be anemic this winter, and spring melt to be enhanced. And this is a powerful feedback for sea ice destruction, a mechanism that could still happen if there were zero net increase in heat accumulation in the arctic. As it happens, though, sea ice destruction and accumulation of heat in the arctic are mutually-enhancing positive feedback mechanisms.
Wayne, I think that was a wonderful integration of available information about new weather patterns and their expected impact on the ice and elsewhere. Another point I see from the pressure maps. It would seem the persistent blocking high over Greenland may prevent the low pressure systems around the arctic from moving in the usual counter-clockwise fashion. I keep seeing low pressure systems arise in the same areas over and over, and move relatively little before fading. It's like we have a standing wave pattern of storms intensifying and weakening in the same areas over and over. Specifically, south of the Bering straight for one, the area from southern Baffin Bay to Newfoundland for another, and the triangular area bounded by Iceland, Svalbard, and Norway for another.
Klon, et al We've now got phytoplankton mentioned on two different threads. I'm with you, we've seen a number of phytoplankton blooms throughout the summer (some quite enormous in size), and you've picked a perfectly representative image. Green ice may be a kind of artifact, but green sea water (this green) is phytoplankton.
Another vote for the greenish color to MOSTLY represent phytoplankton bloom. Ice color could be from spectral aspects of low light angle or camera color correction in low light.... But the green in the water in this mosaic tile, at least, can only be phytoplankton: http://lance-modis.eosdis.nasa.gov/imagery/subsets/?subset=Arctic_r04c04.2012263.terra It would be interesting to look at dissolved oxygen content around the arctic. There isn't enough light now for much photosynthesis. All this organic stuff in the water will only consume oxygen until spring.
Toggle Commented Sep 20, 2012 on Minimum open thread at Arctic Sea Ice
Jimboomega, Jim, Terry, et al The sea surface temperature warmth near the Mackenzie River outlet has been extraordinary and perplexing since around April. Ice started melting here quite early. Temps have been comparable to Mediterranean Sea temps over much of the summer. Lately, when a low-pressure storm passes over, temps fall promptly to readings near the rest of the Beaufort Sea, but then creep back up as soon as the air is still. Salinity maps don't show much surface fresh water here, as you'd expect if the warmth was from oddly warm Mackenzie River runoff. (similar warmth at the outlets of the Siberian rivers HAVE shown low salinity). Vulcanism doesn't really make sense to me--it's the wrong spot in the Arctic for that. The only thing that makes sense to me is that a million years of organic river deposits on the sea bed have finally warmed up enough to start, well, fermenting. If you've dealt with compost piles, you may have experienced how remarkably warm they can get, even in shade. Surely there's gobs of methane on the sea floor here, and lots of other kinds of carbon. Bacteria can oxidize the stuff using either dissolved oxygen in the sea water or sulfate, converting the sulfate to hydrogen sulfide. That HS can then oxidize further with dissolved oxygen back to sulfate, or can get oxidized in the atmosphere. All that oxidation releases energy. Now, this has not been a dramatic hot spot of methane release. But maybe its being oxidized in the seawater before it gets released to the air. MODIS pics don't show the obvious green plankton blooms as elsewhere where there is a lot of mixing/warmth. But there are silicate-based blue plankton, too, and these waters have looked extremely blue in lots of MODIS pictures for months. It would be VERY interesting to know what's happening to dissolved oxygen levels in the sea water here. Fish die-offs? Rotten egg smell from HS? Carbon isotope breakdowns in methane that is released would be illuminating, too. I don't think this is a matter of false readings. We have a LOT of warmth here that isn't credibly from sun, from the Pacific, the Atlantic, and probably not from the river, either.
Jim Williams wrote: "I'd like to have a better handle on how mixed the water became this year too, as I think this is what will determine how much ice there is to melt next Spring." Indeed. I think we've seen some striking geophysical processes at play which together may suggest quite anemic ice formation this winter, (particularly thickness, more than extent). I understand there are only a few buoys which measure the temp+salinity stratification of the arctic waters. But we saw one of these showing mixing near the GAC-2012 storm down to 200 meters, where a lot of the warmest waters reside. We're seeing a lot of other storm systems which are surely contributing to further destratifcation around the arctic. I think destratification of the delicate thermohaline layers may be the single biggest driver of further ice loss in coming seasons. There's a LOT of heat in those 200 meters of water combined, and when de-stratified, all of it becomes promptly available to convect upwards to the surface ice. A whole winter of enhanced convection will play havoc with the underside of the ice. With all the extra water vapor in the air, we can expect more snowfall in the fall and winter. An insulating layer of snow on top of the ice will only enhance the effect of under-ice warmth. In addition, water vapor is itself a greenhouse gas. And while clouds can promote cooling in the arctic summer, clouds only act as an atmospheric blanket when there is no sunlight. Fast melting of thin ice in the spring will then give the albedo-feedback effect a head start in the spring.
Toggle Commented Sep 12, 2012 on Minimum open thread at Arctic Sea Ice
On that topic of exceptional weather, this forecast is still 10 days away, and thus quite uncertain. The "bottom line" seems to be that the weather up there is increasingly stormy. The ice may not be done with destruction this season. Will we call this one GAC-2012B ?
Toggle Commented Sep 10, 2012 on Minimum open thread at Arctic Sea Ice
Chris and AJP Thanks for illuminating the atmospheric chemistry that breaks down methane. I hadn't realized there was that much OH radical available in the atmosphere. But, on reflection, an oxygen-rich atmosphere+UV=potent oxidizing effects, indeed. I gather, then, that this reaction accounts for the somewhat higher levels of C02 in the arctic, when there's a paucity of obvious CO2 production otherwise. Perhaps the great risk of seabed methane, then, is not so much raising atmospheric levels dramatically. as depleting the arctic ocean of oxygen. All this methane only gets broken down with conversion of O2 to CO2, after all. Water has a fairly poor ability to keep oxygen in solution. So when the reaction happens in seawater, hypoxic dead zones could be created. Perhaps we should be monitoring arctic seawater oxygen, as well as temps and salinity. Given the critical importance of the arctic in delivering oxygen to the deep oceans worldwide, that process of oxygen depletion might be the great ecological catastrophe awaiting us from methane stores in the arctic. Steve
Toggle Commented Sep 9, 2012 on Signs of Arctic climate change at Arctic Sea Ice
As long as we're on methane...can anyone explain why methane releases and levels reach their peak around early January, and are at their lowest in July and August? In terms of warming clathrates and thawing permafrost, the annual pattern should be exactly the reverse. I'm thinking that perhaps microbes oxidize the methane before reaching the atmosphere, but that these microbes can't metabolize at the lower temps of winter.
Toggle Commented Sep 9, 2012 on Signs of Arctic climate change at Arctic Sea Ice
Chris Reynolds wrote: "Rather than mass balance, surface melt is perhaps a better thing to look at for the impacts of this anomalous high pressure on the ice." And he also wrote: "What this does mean is that we have feedbacks within feedbacks within the Arctic." Absolutely, and to specify a couple of feedbacks that might not (yet) be obvious to some of us neophytes: 1. Persistent high over Greenland does certainly imply sunny summer skies there. We've seen evidence of a dramatic fall in Greenland ice sheet albedo, and there's every appearance that as ice melts there, more and more dark material accumulates on the surface, lowering albedo further and increasing pace of melt (until the stuff gets thick enough to actually insulate). 2. Persistent highs over Greenland mean persistent clockwise winds around the landmass. This will tend to accelerate transport of the thickest ice in the arctic off the northern coast, and south across the Fram strait, where prompt melting is inevitable. This contributes mightily to net loss of ice volume. A slight mitigation here is perhaps less transport out the Nares strait, but that narrow channel isn't as important as the wide, deep Fram. Drift buoy maps here show the fairly rapid movement of the buoys from the N. of Greenland to the Fram. Some of the ice thickness maps already show ice being thicker above Elesmere Island than above Greenland, reflecting this net ice export near Greenland. Steve
Toggle Commented Sep 8, 2012 on Signs of Arctic climate change at Arctic Sea Ice
There's been a 6.8 magnitude arctic earthquake, north of Iceland. It's on the spreading ridge. These ridges don't often produce big earthquakes like this. Seems likely to me that it's either related to ice mass loss in Greenland and geologic rebound, or just a weird tectonic coincidence. I favor the former. http://earthquake.usgs.gov/earthquakes/recenteqsww/Maps/10/345_70.php
Meanwhile, Jakobshavn Glacier appears to be simply disintegrating: Jakobshavn glacier, August 20, 2012 August 29, 2012
Toggle Commented Aug 30, 2012 on ASI 2012 update 10: (wh)at a loss at Arctic Sea Ice
Rob Dekker wrote: "OBUOY4 and the ice it was on has been terminated, during a rolacoaster ride over the past week through the Fram Strait ice cruncher." Actually,it was just a few hours on Aug 25. With little wind present, it just suddenly started moving west at very improbable speed, until a very sudden stop. It spanned several degrees of longitude across the Fram over a few hours. At the end of this time, the webcam seems to have been knocked around, as it seems to point straight down. I can only think that some boat snagged it and moved it, or perhaps a whale or shark swallowed some undersea dangling cable. The lack of subsequent movement suggests to me the trip ended with a collision with fast ice. Very peculiar event, indeed. http://obuoy.datatransport.org/monitor#buoy4/webcam O-Buoy, oh boy. Steve
Toggle Commented Aug 29, 2012 on ASI 2012 update 10: (wh)at a loss at Arctic Sea Ice
Seke Rob- That PIOMAS volume graph is indeed a masterpiece of graphical representation. It represents a powerful argument for the timescale of disappearance of the Arctic ice cap. I'd suggest that that second Y-axis data detracts from the impact. I'd also suggest that extending the length of the X-axis to show the trend-lines intersection with zero volume would be useful.
Toggle Commented Aug 26, 2012 on PIOMAS August 2012 at Arctic Sea Ice
Neven: Yours is a well-deserved vacation. Please enjoy it thoroughly and recharge your psychological batteries. If doing so means ignoring this blog for a little while...well, the ice and heat and data will still be here when you get back. You've cultivated an exceptional garden here. It's an extraordinary nexus of raw data, useful analysis, thoughtful contributors, lively discussions, and critically important ideas. Considering the importance of the changes at hand for the globe and humanity, you damn well deserve major awards.
Toggle Commented Aug 25, 2012 on ASI 2012 update 10: (wh)at a loss at Arctic Sea Ice
A few thoughts about the Laptev Bite and possible geothermal origin. The Mid-Atlantic spreading ridge essentially changes name to the Gakkel ridge in the Arctic. It's slowly-spreading but has apparently produced volcanoes, as M. Owens has shown here. A USGS map of the Russian end of the Gakkel Ridge is here: http://earthquake.usgs.gov/earthquakes/recenteqsww/Maps/10/120_80.php The tip of the red line seems to me to correlate quite closely with the Laptev Bite. Interestingly, this spreading ridge has a number of active geothermal vents, apart from volcanoes: "Discovery of abundant hydrothermal venting on the ultraslow-spreading Gakkel ridge in the Arctic Ocean" http://noblegaslab.coas.oregonstate.edu/people/graham/publications/Edmonds2003.pdf Arguing against a geothermal vent causing this localized melt, the temperature "signature" of these vents is a mere 0.06 C warming at a km or so above the vents. But maybe we've found hints of a full-fledged volcano there. If so, I propose a name: "Neven's Volcano."
It will take many months for the child to recuperate from the recent bout of Typhoon Fever.
Toggle Commented Aug 20, 2012 on Our beloved ice pack at Arctic Sea Ice
Great animation, Neven!! Right now, the mass of ice blowing out the Fram does dwarf this, but the Nares will indeed drain much of the rest of the thickest ice of the arctic basin. Off-topic for the Nares strait, but on-topic for melting ice in general is the latest changes in those Siberian fires. Over the past 48 hours, the size of the fires along the Aldan River (top right image of the arctic mosaic) has gone from serious, to absolutely alarming. Here are two images, about 48 hours apart. For a sense of scale, the rectangular-shaped loop in the river seems to be about 15 km wide, by my estimation. Previously-burning areas are obviously much worse, but off the field are more areas of frightening extent. It's all been blowing north, towards the Arctic basin. Untold hundreds of tons of soot on an express to the ice...
Toggle Commented Jul 11, 2012 on Nares: from collapse to transport at Arctic Sea Ice