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Post by daffyduck on Jan 12, 2009 15:36:56 GMT
Since we are now in a Cold Phase PDO, several arctic seas included in the extent are warmed by this phase, (where as in the cool phase these seas are cooled.) Warm areas show in this image: (All anomalies in km 2) Source: arctic.atmos.uiuc.edu/cryosphere/So we would expect negative anomalies here:North Pacific: Sea of Okhotsk: -260,000 North Atlantic: Baffin Newfoundland: (-125,000) Greenland Sea: -25,000) St Lawrence: slight - anomaly Barents Seas: -225,000 Kara Sea -100,000 Areas cooled by the cool PDO phase:Bering Sea: Anomaly > 100,000 km 2Following areas usually totally frozen this time of year:Arctic Basic: slight + anomalyBeaufort Sea: slight + anomalyCanadian Archipelago: slight - anomaly Hudson Bay: slight - anomaly Laptev sea: 0 East Siberian Sea: 0 Chuckchi Sea 0 Conclusion: Sea ice is as per the 1979-2000 mean over most of the Arctic. Areas warmed by the current PDO phase have less ice & vice versa. There is every evidence to suggest that we have normality. (Something we haven't had for some time!) We don't have any satellite observations of sea ice pre 1979, which, coincidentally, was the start of the long warm phase PDO. The ice extent of the past couple of years may be either (a) warm to cool PDO transition behaviour, or (b) maybe the norm for cool phase PDO. The last time we had a similar PDO change was back in the late 1940's (When I sum these, I get a net anomaly of -635,000km 2 which appears lower than the total -900,000 for the Northern Hemisphere - but there may be areas not included in the detailed breakdown sea by sea. AMO was also in warm at the same time PDO was in warm….the Arctic was hit by a double whammy. AMO graph: upload.wikimedia.org/wikipedia/commons/thumb/1/1b/Amo_timeseries_1856-present.svg/672px-Amo_timeseries_1856-present.svg.pngAMO Data [close to neutral right now]: www.cdc.noaa.gov/Correlation/amon.us.long.dataAMO plays a role in sea ice: instaar.colorado.edu/meetings/AW2008/abstract_detail.php?abstract_id=56www.cosis.net/abstracts/ICESM2007/00029/ICESM2007-A-00029.pdf?PHPSESSID=49b783f5f5c6bf4c317ddf7ebf9affb0
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Post by ron on Jan 12, 2009 21:54:15 GMT
Very interesting. Must have been something holding the growth back for a bit... water turbulence or winds blowing in a vonstant direction or some such... now back to growth.
I wonder if the pause amount will be related somehow to thawing in the spring, as in this may be an area where the multi-year ice or thicker ice will be. I doubt we'd ever be able to tease that out of the data, but it's got me thinking about this stuff again.
(Kiwi, you've got PM)
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Post by poitsplace on Jan 13, 2009 8:12:16 GMT
Very interesting. Must have been something holding the growth back for a bit... water turbulence or winds blowing in a vonstant direction or some such... now back to growth. I wonder if the pause amount will be related somehow to thawing in the spring, as in this may be an area where the multi-year ice or thicker ice will be. I doubt we'd ever be able to tease that out of the data, but it's got me thinking about this stuff again. (Kiwi, you've got PM) I recall the recent discovery that one of the previously dead thermohaline current sink areas had become active again. It might simply be the warmer water from the gulf flowing in near northern europe. That...and/or the air that's replacing the arctic air that keeps freezing various parts of the world. I thought the discovery of the thermohaline restart amusing as it's the exact opposite of what alarmists would expect from our current cooling (their ONLY way to explain it is if meltwater stopped the thermohaline circulation...but it may actually be getting stronger)
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Post by cyberzombie on Jan 13, 2009 16:09:28 GMT
Are you referring to something akin to the Gulf Stream?
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Post by jorgekafkazar on Jan 13, 2009 17:39:49 GMT
Very interesting. Must have been something holding the growth back for a bit... water turbulence or winds blowing in a vonstant direction or some such... now back to growth. I wonder if the pause amount will be related somehow to thawing in the spring, as in this may be an area where the multi-year ice or thicker ice will be. I doubt we'd ever be able to tease that out of the data, but it's got me thinking about this stuff again. As I posted just before Christmas, there seemed to have been an extraordinary amount of Arctic cloud cover, which insulated the polar region from the cooling effect of the nighttime sky (at 4°K). And yes, the winds were favorable for ice compaction. And yes, at the same time, (I believe) there was significant transfer of heat from the northern hemisphere toward the pole, also suppressing new ice formation. Based on this, I predicted another upward trend within a fortnight, which is what happened. And yes, depending on the relative size of the above factors, there may be an equivalent springtime effect.
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Post by Col 'NDX on Jan 15, 2009 22:34:23 GMT
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Post by ron on Jan 16, 2009 20:54:04 GMT
So this means that 2009 Ice Extent is second only to 2003 in the (7+) years since the beginning of the AMSR-E?
As always, Kiwi, you do some awesome work!
(PS In the legend, shouldn't the term be "estimated" or "estimated from proxy data" or "reconstructed from correlated data" rather than "interpolated"? To me, interpolated infers that you have known values from the same source as the graph.
Also, shouldn't the mean of 79 - 00 also be labelled as "interpolated" or whatever?)
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Post by kiwistonewall on Jan 16, 2009 21:59:50 GMT
Hi Ron, the "interpolated" data is interpolated from Goddard monthly means. i.e. constructing a smoothed daily curve from a single monthly mean. Yes the mean is also interpolated.
There is no proxy data involved. There has been an adjustment to align the Goddard series to the JAXA series, but I used more then 5 years of overlapping data to do that (way way back in the 2008 ice thread). I'm convinced that this is perfectly valid, and any errors introduced are very small.
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Post by kiwistonewall on Jan 17, 2009 20:26:49 GMT
ice extent continues on its current growth spurt: Edit 17th: complete stop.
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Post by kiwistonewall on Jan 18, 2009 5:57:16 GMT
Provisional result for 17th is a small reduction in extent, so the recent advance might halt for a few days.
However, the Great Lakes are ahead of mean for this time. Has Al Gore visited the Great Lakes region recently? (my wife asks that!)
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Post by walnut on Jan 18, 2009 15:37:55 GMT
Kiwi, do you have a url which shows current Great Lakes ice extent? I would like to see that.
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Post by chrishotz on Jan 18, 2009 19:57:36 GMT
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Post by kiwistonewall on Jan 18, 2009 21:19:46 GMT
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Post by Ole Doc Sief on Jan 19, 2009 0:53:01 GMT
Greetings Kiwi! I hear the land down-under is Baking, 105F....I could use some of that heat about now. So how is the Antarctic Ice doing so far??
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Post by kiwistonewall on Jan 19, 2009 4:16:16 GMT
Antarctica has more ice than long term mean: arctic.atmos.uiuc.edu/cryosphere/IMAGES/current.365.south.jpgDown under is COLD (relatively speaking!) (my closest station SE Melbourne at Scoresby has Average for January so far: nights(min) 2C lower & day max: 1.1C lower. 3 days >30 so far, 1>35 (8>30 expected for month- unlikely we'll reach that this month, though 6 or 7 likely) (Jan 2008 had 9>30 with 4 >35 - 2.7>35 expected.) Sure we have the odd hot day, but nothing like the last couple of years, and lower than the long term means. I guess if you go out in the middle of the desert, find a hot rock (or maybe an air-con outlet) you'll get something high - But, nearly all of Oz is having colder than normal summer. Australia is a HOT DRY DESERT continent. We expect to have hot summers. We are having a merely warm one.
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