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siili
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Topaz is updated once a week, supposed to be on fridays but they have had many delays lately, but now they have daily forecast maps of temperature, displacement, concentration and thickness untill 2/9, http://topaz.nersc.no/topazVisual/matlab_static_image.php?action=NA_ARC_NWA_Function&file_prefix=ARC&match_date=20100902&depth=0005&variable_name=hice
Maybe the melt is gettin to North Pole webcam #2? In the latest image, although it's still not totally clear, something is going on, it looks like more leads are opening up and the camera is starting to tilt. Compare the location of the windgauge to the horizon in the latest set of images to previous ones. http://www.arctic.noaa.gov/latest/noaa2.jpg
I think that the reduction in extent is far from over, and that JAXA will pick up pace again. As said before there's a lot of ice on the border of 15% concentration, where a small change in the situation on the ground has a big impact on the numbers. There is also the possibility that even what looks like close to 100% concentration solid packice on the passive microwave images like Uni Bremen, about a full degree into the pack at 78N 152W, on Healys webcam looks like very small floes in advanced stages of decay. The weatherforecasts are also showing a continuation of the the present weather the following days which should give more compaction and outflow.
If we have any pixel-graph counters online, todays Uni Bremen extentgraph shows a very hefty downtick after an increase, so if that transforms into tomorrows Jaxa numbers, they are going to be huge.
Jaxas preliminary numbers are in, at 5910781km^2, 70625 less. Two interesting things could be noted, the history of (two-day averages) losses is about 60k,60k,40k and 70k, and if 60k was the true 3 days ago, 120k should be the unsmooth loss for today. The other noteworthy thing is that in the preliminary Jaxa-images there is a rather big artifact in the choppy sees of the deep low south of the iceedge which will be corrected in the update later today, if that is counted in the extent number, well...
Ask the internet http://pic6.piczo.com/sagashule/?g=18624614 which gives in latin: Auditor fortuna juvat
Lyckan står den djärve bi or The one who dares (gets happiness or succedes) is my take of this Norse saying. Any forecast on todays numbers for extent Patrick? I had a peek on the other side, and they could be in for a reall chocker tomorrow.
Second that, but looking at the Jaxa timeseries, the Fram outflow is increasing extent, but then looking at the wind and ice bouy drift maps, i don't think the reall move has started yet. From Amundsens measurments the whole southern Beaufort is full of 10 C warm waters, which is starting to move at the ice guided by the increasing high over the CA. And thinking about the closing whole, MODIS had a very good day yesterday http://rapidfire.sci.gsfc.nasa.gov/subsets/?subset=Arctic_r05c02.2010227.terra
If it will cure your headache, you might as well use the Julian calender at least untill 2100 when it matters next time...
Sorry to be a nitpick Neven, but since i am an astronomer, Julian Day is in fact something different http://en.wikipedia.org/wiki/Julian_day, what you are using could perhaps be called day number or formaly last three digits of an ordinal date.
The weather in the coming 2-3 days looks like it's shaping up for the ultimate test of Nevens floataway hypotesis with a very deep low forming over Novaja Zemlja, with the possibility of a high over Greenland giving a hand in blowing away the biggest iceisland ever or probably at least disrupt it further from it's already bad state. Todays early microwave images show the low concentration areas spreading. The same models are forseeing southerly winds and increasing surface temperatures over the Beaufort, so if area and extent don't dip now they probably never will. But i have been a bad forecaster before, so probably something completely different happens.
Toggle Commented Aug 14, 2010 on Animation 12: year to year at Arctic Sea Ice
I still think that part of the slowdown in areadecrease could be due to cloud interference, not all of the fast changes in the look of the big "holes" in the ice of the Beauford are real. That said the compaction, or at least movement of the ice on the Alaska-Siberian side towards the CA looks to be increasing according to PIPS2 and the weatherreports. So i think we should see a renewed decrease in area as well as extent the coming days. It will be very interesting to see the final report from the melt measuring buoys and the reports from the Healy how the melt happend this season, if there was more warm water pushed under the thin ice, melting ice even when the skyes were cloudy. The Amundsen is also on it's way to the Beaufort through the Amundsen Gulf in 9-10 C warm water. If Barber is abord again we could expect even hotter news soon. The Healy has teamed up with his Canadian mate and started to follow the straight line towards the pole on the A1-A3 track, which will take them to 75 N before it will turn to the south again. Follow the action and some reports on how they use different satellites to navigate on http://continentalshelf.gov/missions/10arctic/welcome.html
Also on the Greenland side of the arctic things are moving fast nowadays, buoy 90029 has moved some 50km in two days towards Fram strait pushed by a not to impressive low which looks like it is going to intensify in the coming days, like the "minidipole" combination of a low and high guiding more ice into the CA.
Toggle Commented Aug 13, 2010 on Animation 11: Canadian Archipelago at Arctic Sea Ice
This is a very captivating subject, and it looks as we we put PIOMAS present about 0.5 *10^4 km^3 remaining ice into Maslowskis graph and interpolate lineary into the future it looks like we are undershooting his most pessemistic graph. But from his graph, his like most (all?) present models has the last stand of the arctic ice above the CA, with the current fast loss of old ice from there this may not be how the very close future places out. The ice appears so thin and mobile now that short term weather probably start to play a big role in the way the future plays out and from which way open water closes in on the pole.
Maybe the hindrence to navigation will not be as grave as classical knowledge would tell us due the changing state of the ice in the arctic basin above the CA. If models are to give us any guidence, the change from one year ago http://topaz.nersc.no/topazVisual/matlab_static_image.php?action=NA_ARC_NWA_Function&file_prefix=ARC&match_date=20090812&depth=0005&variable_name=hice and now http://topaz.nersc.no/topazVisual/matlab_static_image.php?action=NA_ARC_NWA_Function&file_prefix=ARC&match_date=20100812&depth=0005&variable_name=hice is striking with all 3+m thick, 5+ years old ice gone from the basin beeing advected out to the Beaufort during winter, leaving younger, thinner, more fragmented and mobile ice left to enter the CA. And litttle hope for that ice ever to return after a lap in the Gyre, since most of it is already in advanced stages of melt and soon gone too.
Toggle Commented Aug 13, 2010 on Animation 11: Canadian Archipelago at Arctic Sea Ice
Lodger, i truly don't understand where all your anger is coming from, and why you direct it at me? I came to this site to learn, and discuss what i found in the learningprocess to to be interesting, puzzeling or whatever, in the hope to get an stimulating discussion going and increase our communal knowledge. True i am a scientist by training, but in a very diferent field even if some stuff in similar. But if this place isn't big enough for both of us, i'll be a pure observer in the future, Thanks everybody for a good time.
I agree that i find the daily numbers puzzleing considering the look of the maps, but the icemovement is very organized at the moment and has been for a few days, if you look at the buoymap http://iabp.apl.washington.edu/maps_daily_arcticbasin.html and compare to the pips2 http://www7320.nrlssc.navy.mil/pips2/idis.html they show coherent motion in the expected directions arroud preasurecenters, clockwise at Highs and anticlockwise at Lows http://www.meteo.uni-koeln.de/meteo.php?show=En_We_We
Maybe slightly off topic, but very interesting to me. When we talk about the present weather situation in the arctic, we ususlly use the Uni-Köln map right? http://www.meteo.uni-koeln.de/meteo.php?show=En_We_We but another look at the same time and place is given by e.g. the initialisation used to start the GFS model http://www.wetterzentrale.de/topkarten/fsavnnh.html When i compare theese, they are slightly different as i would think from the somewhat ill defined observables. But according to Lodger this is a red herring since Aqua gives us perfect data. But does not Aqua pass overhead about twice daily, wouldn't that give very good spatial coverage there and then, but rather patchy temporal coverage, four times daily when a preasurefield is given? I am an absolute beginner in this area with a sincere strive to learn, so please help me out here.
So you think the 1050hPa was real?
I don't think that we should read to much into each update of the details in the reconstruction of the pressurefield, since it is based in essence on a very sparse grid of preasure reporting buoys, complemented with two ships. http://www.sailwx.info/shiptrack/shiplocations.phtml (zoom in on the arctic) Click on the buoys to see a very nice outline of their movements. A few days ago, the top preasure was absurdly high at 1050 something hPa, and yesterday it almost vanished. If we look at the models both ECMWF and GFS shows it stable for 3 more days, and they agree on the low over the pole, so both the Gyre and Fram outflow should have a good chance to get going.
Don Perovich has released data from one of the Ice Mass Balalance (IMB) buoys of a new type for the more variable arctic able to do work both in ice and water http://imb.crrel.usace.army.mil/2010B.htm but as usual with new machines, the data is not always easy to use for an outsider, but give it a peek. When the old buoys show jumps in the icedepth, it is usually due to an icebear using it as a scratching stick. And Healy spotted one a few days ago, so who knows?
Three days ago i dared you to forecast when the Northen Searoute should open, without any contestants, but today it must be very close to the point when at least Henry Larsen wouldn't hesitate a second. It is still a bit cloudy, but it could be possible to trace a line through the black water in todays Terra image http://rapidfire.sci.gsfc.nasa.gov/subsets/?subset=Arctic_r04c05.2010222.terra.367.250m&vectors=coast The radarimage also show that the time is getting near http://www.seaice.dk/iwicos/latest/envisat.GMM3d.n.20100810.gif And if we are to believe the models, the remaining ice should be fairly thin in the area http://topaz.nersc.no/topazVisual/matlab_static_image.php?action=NA_ARC_NWA_Function&file_prefix=ARC&match_date=20100810&depth=0005&variable_name=hice And the forecasts like PIPS and ECMWF looks like the icemovement pattern will persist for some time, moving the ice away from the coast. So we'll see what the yachts will do. And if you look closely at the radarimage on the other side of the pole, you'll spot the new Patrick iceisland drifting free on it's way to Nares strait.
Toggle Commented Aug 10, 2010 on Breaking away from the pack at Arctic Sea Ice
May i make a forecast dearest Lodger? If so i look into my crystal ball and see a big thing in the sky with a certain colour, covering the southern portion of the tounge of old ice beeing pressed out into the varm waters from the mighty rivers by the now mysteriously gone glorious high pressure. And i haven't looked at any optical/IR images, promise!
To be of the net souds like a good thing for the mind that i will try shortly, but my last day is not over yet, so i'll go on untill Neven stops me. Very nice read Nick, that i probably will ruin by a little ramblings. The icepack indeed look very different this year from above, and if PIOMAS is anywhere near the truth that could be the reason for it, but anyway previous times with this look of the ice, was still on the outside in 2008, and then it was roughhandled by perfect storms that helped to take up all the energy. What if, this year there are so much ice potentially meltable at the same time, but that the energy needed to do that just is not there? There has been little insolation when it matters, when the Sun is high in the sky, and now when we get clear skies, maybe the outgoing radiation is the greater than the incoming? And the open water areas just didn't get that much warming from the clouded Sun, so even the water can do much melting now? And the inflows of warm water from the Atlantic and Pacific, just maybe there hasn't been that much of that either this year? But think of the science in studing next melt season, when large parts of the arctic is made of Barbers, overgrown rotten ice, what will happen to that, if only the forcings are a little more like 2007 next year? We don't want to get to Maslowskis state three years ahead, do we?
Toggle Commented Aug 9, 2010 on Any way the wind blows at Arctic Sea Ice
Thanks Anu for the pictures, what i have ment by a pink cloud, which in hindsight is not the best designation, is situated in the upper right corners of the square. That very white area in the microwave image=high concentration of ice, is at the same place at what looks like a very opaqe cloud with no hints of ice/water below it. When i started to look at this i was a bit surprised that most clouds over the artic is not totally opaqe, you usually see something through them. The opaqe pcs are usually situated over land, where one could guess that they are high clouds created by the greater energy over warming land, compared to the ice? If I dare to suggest that you repeat your excersice for the next days pair of microwave/optical you will find that the 100% concentration white area is transformed into what you find over most of the other parts of the western arctic, more or less broken ice. A slight complication, and other downside to the bad choise of pc, is that the microwave images AMSR-E is sitting on the Aqua satellite, not Terra which is the one with the infrared detector, and if the clouds move fast, the look between Aqua and Terra can be slightly different, another experiment perhaps. I hope this is making some sense, i know i am challenged in my communication skills ,maybe you can become interpreter between Lodger and me, if you can follow us both?
Toggle Commented Aug 9, 2010 on Any way the wind blows at Arctic Sea Ice