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Post by throttleup on Jun 23, 2012 18:17:29 GMT
Happy Summer Solstice to everyone! This thread has turned into more of a blog than a discussion forum, but, whatever. t'stat, I didn't want you to feel lonely so I thought I would make a comment on your Arctic Ice blog. And, you're doing a wonderful job at it, I must say.
Perhaps the view of some is that it is just ice. It has melted before and re-froze. It will do so again. Some think Winter-Summer are mythical cycles, but there seems to be something behind them. I think it's axial tilt, but what do I know? I'm not a climate scientist.
I suppose if one is in the "we're all gonna die!" camp, then following the ice capades is an engrossing activity. And I have no problem with that and I honestly do appreciate your dedication, updates and information here.
I'm not really in the "we're all gonna die!" camp so I don't have much to add to your blog today and I apologize for that. I'll try to do better next time.
So many different things affect ice extent, area and volume from one day to the next that perhaps some feel it's best to just sit back and take it all in and sometime afterwards make a comment or judgement on what we just witnessed and why.
In the meantime, I'm sure many do read your updates and appreciate them and are probably just too busy enjoying the Northern Hemisphere Summer to comment.
Perhaps in late fall and after all the "we're all gonna die!" comments have subsided they'll comment more here on your blog.
Keep up the good work.
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Post by thermostat on Jun 25, 2012 5:40:09 GMT
Throttleup,
I appreciate your positive comments. Thanks. Much appreciated.
That said. The dipole anomoly that drove those sea ice reductions a while back is long gone and persistent low pressure has been the norm in the Northwest Arctic since then. The effect of this weather pattern is the curent issue.
Still, let's not forget 'the Arctic fringe'; ie, Hudson Bay, Baffin Bay and the Canadian Archipeligo(I suggest that we simply forget the Barent's Sea and Kara Sea, since ice in these areas is essentially already gone this year, but, whatever.
I suspect that both Hudson's Bay and Baffin Bay are about to melt substantially (based on looking at the upcoming weather predictions).
I suggest that specific indicators such as the Point Barrow landfast ice, the Nares Strait Ice bridge and the 'Northwest Passage', and others, will tell us a lot about how 'the times may be a'changin', or not.
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andor
Level 2 Rank
Posts: 60
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Post by andor on Jun 25, 2012 8:45:12 GMT
But nobody reckognizes the fact that the south pole has a record temperature of -100.8 deg F
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Post by thermostat on Jun 27, 2012 3:06:59 GMT
But nobody reckognizes the fact that the south pole has a record temperature of -100.8 deg F andor, Scientists interested in climate do think about the whole system; those guys wonder, even when it is about the current local weather here or there. But nevertheless, this particular thread is about Arctic Sea Ice, where we care about the current local weather, as well as the longer term processes occurring at the other end of the planet. More generally, I would comment; temperature extremes happen in various times in various places. Well documented trends are more useful in identifying and understanding climate phenomena and the physical forces that drive them.
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Post by thermostat on Jun 27, 2012 4:09:21 GMT
Getting back to the weather in the Arctic, Sea Ice junkies love the German site Wetterzentral www.wetterzentrale.de/topkarten/fsecmeur.html because it has a nice graphic and quite extended weather forecast. Under ECMWF, click on N-Hem and then 850hPa-Temp.,SLP to click through the exended arctic forecast. The weather has been changing over the Arctic Sea and the conspicious low pressure system north of Alaska is dissipating. The current forecast shows relatively neutral conditions that are providing for relatively warm surface temperatures extending far over the Arctic Sea (click though the various forecast pages and note how the green area (below freezing) fragments and diminishes. Thus, the melt events of the previous 10 days or so will now be changed due to the new weather pattern. I would suggest that there will be less expansion of the central ice pack and more melting in situ. The significance of expansion in the main ice pack and the potential of this dispersion to facilitate melting is of interest and will be followed as the melt season progresses. (for example, how might the present fracturing of the main ice pack allow for increased absorption of solar radiation around the summer solstice?) That said, immediate reduction in Sea Ice extent will be driven by melting in Hudson Bay and Baffin Bay, with the recent events in the Greenland Sea being a wild card. One can expect a steady reduction in total Arctic Sea Ice extent over the coming weeks. Another resource that Arctic Sea Ice junkies love is the satellite images from Modis. A user friendly, if somewhat limited version can be found here rapidfire.sci.gsfc.nasa.gov/imagery/subsets/?mosaic=Arctic.2012178.terra.4kmAs mentioned previously, people are watching a couple of specific places; the Point Barrow fast ice (more for historic 'political' reasons than anything else; the Northwest Passage, for obvious historical reasons; and the Nares Strait - because is could provide a conduit for the export of multi-year Sea Ice). More broadly, people are watching that fragmentation of the central arctic ice pack... and speculating
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Post by thermostat on Jun 27, 2012 4:44:41 GMT
Happy Summer Solstice to everyone! This thread has turned into more of a blog than a discussion forum, but, whatever. t'stat, I didn't want you to feel lonely so I thought I would make a comment on your Arctic Ice blog. And, you're doing a wonderful job at it, I must say.
Perhaps the view of some is that it is just ice. It has melted before and re-froze. It will do so again. Some think Winter-Summer are mythical cycles, but there seems to be something behind them. I think it's axial tilt, but what do I know? I'm not a climate scientist.
I suppose if one is in the "we're all gonna die!" camp, then following the ice capades is an engrossing activity. And I have no problem with that and I honestly do appreciate your dedication, updates and information here.
I'm not really in the "we're all gonna die!" camp so I don't have much to add to your blog today and I apologize for that. I'll try to do better next time.
So many different things affect ice extent, area and volume from one day to the next that perhaps some feel it's best to just sit back and take it all in and sometime afterwards make a comment or judgement on what we just witnessed and why.
In the meantime, I'm sure many do read your updates and appreciate them and are probably just too busy enjoying the Northern Hemisphere Summer to comment.
Perhaps in late fall and after all the "we're all gonna die!" comments have subsided they'll comment more here on your blog.
Keep up the good work. throttleup, I wanted to reply more specifically to your excellent comment. As I figure forum members can tell, I'm very curious about the Arctic Sea Ice, an Arctic Sea Ice junkie, I guess. I have followed the annual melt with increasing interest over the past few years; I'm thinking about 4 years with increasing interest over that time. In case it matters, I paid no attention whatsoever in 2007. And, I'm a Ph.D. scientist. I suspect that one thing that is relevant here is that I have a useful perspective on how scientists think and communicate with each other, since that is the world I live in. That said, the evidence indicates that the Arctic is changing in ways that are not consistent with what should be expected if there was not some unusual driver. Axial tilt, or some other mechanism. Careful analysis can shed some light, I think.
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Post by thermostat on Jun 27, 2012 6:07:35 GMT
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Post by icefisher on Jun 28, 2012 16:20:05 GMT
If you zoom in to the highest resolution you will see the larger melt ponds that have formed on top of the ice sheet. It is the conspicuous expansion of the melt zone that is of particular interest.
Yep I have to agree with you to some extent. Greenland being within a super region including the arctic is relevant to this thread but the Antarctic is not.
The similar effect in Greenland and its absence in the Antarctic strongly suggests a regional driver as a careful analysis from a global perspective strongly pulls you back to looking at this from a regional point of view. Just I am confused why a scientist would then consider axial tilt. Perhaps you can explain how axial tilt provides a unipolar effect.
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Post by thermostat on Jun 30, 2012 1:52:30 GMT
Icefisher,
I agree, the Greenland ice sheet qualifies as a relevant topic with regard to 'Arctic Ice'. I further agree that comparing the Arctic with the Antarctic is a whole different subject.
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Post by thermostat on Jun 30, 2012 2:15:28 GMT
Nares strait update; the ice bridge is has recently fractured and is now breaking down; rapidfire.sci.gsfc.nasa.gov/imagery/subsets/?subset=Arctic_r03c02.2012181.terraThe significance; breakup here provide an additional channel of export for multi-year ice into Baffin Bay, where it will melt away. How long will it take to open this channel? A couple of weeks is the current bet. Relevance to Arctic Sea Ice Extent; increased summer export through this channel leads to decreased minimal Sea Ice Extent. Significantly, the ice exprtred through this channel tends to include thick, multi-year ice. Thus, opening of this export channel affects longer term Arctic Sea Ice maintanance.
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Post by thermostat on Jun 30, 2012 2:33:50 GMT
The thing that stands out this year regarding the Arctic Sea Ice melt is the vulnerability of the ice pack in the central arctic. The thinning of the core ice pack, in particular is becoming a conspicuous factor. Thus, while melt promoting weather patterns could easily lead to a record melt, even neutral or somewhat cold weather patterns could produce an historically low minimum, if not a record.
At the same time, the physical factors that are introducing the heat into the Arctic Syatem that is driving this melting are increasing in magnitude. Summer weather is becoming less of a factor in determing the melt as the ice pack thins.
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Post by glennkoks on Jun 30, 2012 16:17:47 GMT
Jun 19, 2012 Sea ice tracking at record low levels
nsidc.org
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Post by thermostat on Jul 2, 2012 4:57:21 GMT
[img src="[/img] "] Jun 19, 2012 Sea ice tracking at record low levels nsidc.org As glennkoks indicates above the observations for this June indicate Arctic Sea Ice levels are quite low for this date. This observation is confirmed by the Cyrosphere Today Sea Ice Area measurements. The Sea Surface temperature anomaly in the Arctic region is also of interest; ocean.dmi.dk/arctic/satellite/index.uk.php(see Sea Surface Temp anomalies, under, select parameter.) It shows ocean heat relevant to the present melt.
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Post by thermostat on Jul 2, 2012 5:11:58 GMT
The current weather forecast for the Arctic indicates that a high pressure system will persist north of Alaska for the next week + www.wetterzentrale.de/topkarten/fsecmeur.htmlThis current weather pattern is a distinct change from the latter part of June and is likely to be conducive to increased sea ice reductions as we enter the historical peak of the Arctic melt season. That said, this is no classic 'dipole anomaly'. It will be interesting to see what happens.
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Post by thermostat on Jul 4, 2012 2:35:45 GMT
No sooner said than the weather forecast moves forward a bit. Now Wetterzentrale is forecasting a dipole anomaly to form over the Arctic Sea next week. www.wetterzentrale.de/topkarten/fsecmeur.htmlThe implication of the weather forecast is that the present rapid reduction in Arctic Sea Ice will continue and could even increase during the first half of July. This is particularly significant because the next few weeks historically show the peak melt rate. Also, in the past two years, reductions in the melt rate that occurred in July had an important effect on reducing the ultimate minimum; see for example, www.ijis.iarc.uaf.edu/en/home/seaice_extent_prev.htmWhile 2012 is not displaying the weather extremes observed back in 2007, the diminished ice pack of 2012 is much more subject to melt under milder conditions. Events in July will be important in determining the outcome.
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