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Since stadium waves have actually overwhelmed the thread, I'll go ahead and point out that Curry's pet uncertainty monster seems to be selective in who it bites.
Freezing season 2013/2014 open thread 1
Here's a first open thread for this freezing season, which will be followed by monthly instalments. I apologize yet again for having been so inactive on the blog. I'm the kind of person who shuts off certain activities when being too busy with momentarily higher-priority stuff, but with the exte...
NJSnowFan, et al., you could also just ask NJSnowFan if s/he understands the technical detail of the response. A simple request for verification of understanding usually results in the separation of trolls from the curious general public. Unless, of course, this is meant to be an experts-only forum/blog.
Crack is bad for you (and sea ice)
The previous pun - cracks of dawn - was wearing off, and the comment section was getting full, so here's a new pun and blog post dedicated to the cracking event that started in the Chukchi and Beaufort Seas a couple of weeks ago, and then moved on to the multi-year ice against the Canadian Archi...
James, I believe it's spelled with an "a": "bear".
PS: all should spare a few milliseconds of lament for 2009, who just lost its only daily CT SIA record anomaly. 2012 now owns 158 daily record area anomalies -- 43.3%.
As Sea Ice Declines, Winter Shifts in N. Alaska
As winter sets in, the Arctic Ocean freezes up. But because waters near the continental land masses warm up so much during the melting season (see for instance this image from August 11th 2012), they have to give off a lot of heat before they're cold enough to freeze. The waters warm up so muc...
2012 CT SIA, by my count, now has 139 daily minimum records. 2007 is now tied with 2011 for second place, with 67 each. 2006 = 44, 2010 = 26, 2009 = 15, 2004 = 5, and 2008 = 2.
Average daily anomaly for the year is -1.36198. For 2007, it ended at -1.284005. 2011 = -1.253222.
CT SIA finally above -2 million km2 anomaly mark
After three full months the Cryosphere Today sea ice area anomaly trend line has finally left the zone below the 2 million square kilometre mark: As usual, Jim Pettit is serving the current statistical hors d'oeuvres: CT SIA area increased by 203k km2 yesterday; that was the fifth double centu...
Other numbers:
CT SIA melt season daily average:
2012: 68,300.6 km2
2003: 60,698.8 km2
2008: 60,150.1 km2
2010: 58,053.6 km2
1993: 56,494.9 km2
Full record linear est: 203.684
Cherry-picked 1996-2012: 809.233
ASI 2012 update 11: end or beginning?
During the melting season I'm writing (bi-)weekly updates on the current situation with regards to Arctic sea ice (ASI). Central to these updates are the daily IJIS sea ice extent (SIE) and Cryosphere Today sea ice area (SIA) numbers, which I compare to data from the 2005-2011 period (NSIDC has...
Brad Plumer has a piece at WaPo. I pointed him to the more recent model-observation comparison that's in the main post. I'll post the link here, and maybe an exchange of traffic will occur.
http://www.washingtonpost.com/blogs/ezra-klein/wp/2012/09/20/when-will-the-arctic-be-ice-free-maybe-four-years-or-40/
Models are improving, but can they catch up?
All models are wrong, but some are useful, as the saying goes. However, when looking at how Arctic sea ice decline is modeled, one might be tempted to say that all sayings are useful, but some are wrong. To be fair, I should be the last person taking a piss at climate models. Hundreds of brill...
From the Dep't of Ice-o-terica: 2012 CT SIA now has 102 days that each have the record minimum for their respective dates (74 (and counting) of these are consecutive). 2007 is now at 100. If the minimum has been hit at 2,293,761.3, then the average daily melt for the 2012 melt season is 70,461.4, almost 10k above the previous record of 60,698.8 in 2003.
Minimum open thread
The reports of my return are greatly exaggerated. I'm still at my holiday address, on the wretched 56K modem. As I'm going to be realy offline now for 2-3 days to visit my 97 year old grandfather and his 400 litre wine cask, I thought an open thread would be a good idea. Can we start speculatin...
Dep't of Esoterica. Something I didn't expect to happen this year: CT SIA is now lower than the CT SIA 79-08 anomaly.
More details on PIOMAS volume loss
Quite soon after the inception of this blog, data from the PIOMAS model became a prominent element in discussions on ice thickness and volume. Though corroborated by on-the-ground observations and satellite data, PIOMAS remained a model and so practically everyone was careful in not attaching to...
From the Department of the Obscure:
CT SIA for 2012 now has 83 daily record lows in area. Only 2007 stands in the way -- currently at 107 and obviously set to lose ground over at least the next two weeks. 2011 and 2012 currently account for 206 of the 365 daily record lows in the record.
Melt season daily average is still around 76k.
Record dominoes 6: IJIS sea ice extent
There are several scientific organisations that keep an eye on the Arctic sea ice cover and put out graphs to inform us of the amount of ice that is left. You can see most, if not all, of them on the ASI Graphs webpage. I expect the record on most of these graphs to be broken in weeks to come. -...
Jack, everything is fodder for denialist misinterpretation. In this case, they'd have to demonstrate that Arctic vulcanism has increased significantly over the past 30 years.
Arctic Ocean Circulation - Mixing - Effect on Ice
There is a lot of information on Arctic Ocean Circulation available via a google search. Much of it is prior to the 2007 minimum and most does not provide for comments as we get here in the Arctic Sea Ice blog. As the Sun dips below the horizon, we are about two months past the northern Summer S...
One more small piece of esoterica that might have rhetorical value: CT Area has been below 50% of the 1979 daily numbers for the last week. It had never dropped below 50% before this season.
Greenland melting breaks record 4 weeks early
There already was a suspicion that this year would become a record year for Greenland ice melt, after all the real-time information we received from Dr. Jason Box with regards to the reflectivity of the Greenland Ice Sheet (see Dark side of Greenland), the extremely high temperatures in much of...
To add to Jim's post, and for what it's worth, we're also 164972.5 km2 from setting the melt season CT area loss record.
2008 10.8871598
2010 10.739908
2012 10.7221873
2009 10.4284585
2007 10.3977587
2002 10.2877698
1993 10.2820811
And just in case you're curious, the biggest freeze season gainers in the CTA record:
2007 10.9712765
2008 10.8495002
2011 10.8037708
2009 10.38744
2000 10.3575464
2002 10.3043513
2010 10.0722902
Greenland melting breaks record 4 weeks early
There already was a suspicion that this year would become a record year for Greenland ice melt, after all the real-time information we received from Dr. Jason Box with regards to the reflectivity of the Greenland Ice Sheet (see Dark side of Greenland), the extremely high temperatures in much of...
More fun with numbers:
CT Area loss for the 2012 melt season (day 88 to present, by my count) is now 10.5054 million km2, the third highest area loss in the record, with roughly 30 days to go. With such a short melt season, that makes the average daily loss gigantic (currently 79,587 km2 per day, almost 19k km2 per day greater than the next highest (yet full-season) total (2003)).
Peeking through the clouds 3
Clouds blocking our view of events below make the False-Colour Composite images Environment Canada makes of the LANCE-MODIS satellite images very welcome (for further explanation read the first and second blog posts with the same title), especially after they have been 'declouded' by commenter d...
The 60-day CTA daily average is once again over 100k, the 15th such period this melt season (all of 1 such period occurred prior).
New CAPIE record
The trend line on one of our in-house charts has broken last year's record: 56.85% vs 57.39% on August 12th 2011. CAPIE stands for Cryosphere-today Area Per IJIS Extent, and it tells us something about the compactness (official scientific term) of the ice. It all revolves around the different d...
And today's 90-day daily melt average for CT SIA is 93,607. Before 2012, it had never been above 88k. It's been 90+ for five days.
CT SIA anomaly drops below 2 million km2
With a drop of 174,867 square km for July 17th reported by Cryosphere Today (run by the Polar Research Group at the University of Illonois at Urbana-Champaign), the 2012 sea ice area anomaly has dropped below 2 million square kilometres, compared to the 1979-2008 mean: So what, one may ask. It ...
FYI: the largest 60-day drop in the historical record (CT): -6196017.7 km2, a sixty-day average of -103266.962 km2 per day.
The eighth consecutive 60-day period over -6 million km2 (one period prior).
CT SIA anomaly drops below 2 million km2
With a drop of 174,867 square km for July 17th reported by Cryosphere Today (run by the Polar Research Group at the University of Illonois at Urbana-Champaign), the 2012 sea ice area anomaly has dropped below 2 million square kilometres, compared to the 1979-2008 mean: So what, one may ask. It ...
I apologize for not having paid attention to the weather, but to what extent have dipole conditions emerged during this melt season?
CT SIA anomaly drops below 2 million km2
With a drop of 174,867 square km for July 17th reported by Cryosphere Today (run by the Polar Research Group at the University of Illonois at Urbana-Champaign), the 2012 sea ice area anomaly has dropped below 2 million square kilometres, compared to the 1979-2008 mean: So what, one may ask. It ...
More statistical esoterica: all of the daily minimum area (CT) records have been set within the last 8 years. Fifty-two percent (191) have been set in the last four years. Forty-four have been set this year so far. 2007 contains 122, 2011 = 106, 2006 and 2012 are tied at 44.
ASI 2012 update 7: steady as she goes
During the melting season I'm writing (bi-)weekly updates on the current situation with regards to Arctic sea ice (ASI). Central to these updates are the daily IJIS sea ice extent (SIE) and Cryosphere Today sea ice area (SIA) numbers, which I compare to data from the 2005-2011 period (NSIDC ha...
I'll post on area, for what it's worth and despite the known problems. We've been above the pre-existing 60-day drop total record for three consecutive days now (above a century daily average). Also, only one five-day drop total has been this high (81260) this late in the season (82760 - 2002).
ASI 2012 update 7: steady as she goes
During the melting season I'm writing (bi-)weekly updates on the current situation with regards to Arctic sea ice (ASI). Central to these updates are the daily IJIS sea ice extent (SIE) and Cryosphere Today sea ice area (SIA) numbers, which I compare to data from the 2005-2011 period (NSIDC ha...
Based on a simple linear extrapolation + look at the ice, I came up with 2.89 for area. I'd like to know who polled more than 4.0. That would require an average daily drop for the next sixty days of around 26636 km2, which is more than 3 STD below average daily for those sixty days (44826).
For what it's worth, the current sixty-day area drop (Cryosphere) is now the second largest in the record for any sixty-day period:
-6.0621495 (1985 - Days 151-210)
-5.9827003 (2012 - Days 133-192)
Polls July 2012
ATTENTION: new polls in the right hand bar, closing July 31st. With the release of the July SIO report I also release the results of the two ASI blog polls in the right hand bar, that closed on June 30th. First off the poll for the NSIDC minimum monthly/September sea ice extent that received 27...
amendation: "The recent run" > "The recent nine-day run"
ASI 2012 update 5: when graphs agree
During the melting season I'm writing (bi-)weekly updates on the current situation with regards to Arctic sea ice (ASI). Central to these updates are the daily IJIS sea ice extent (SIE) and Cryosphere Today sea ice area (SIA) numbers, which I compare to data from the 2005-2011 period (NSIDC ha...
I'd add to Jim's posts that the ten day period ending yesterday was just 4015 sq km short of the 1999 10-day record drop. The 1999 run that holds the record was almost the first 10-day century run on record. The recent run is the third on record (1995, 2010). Drop runs are far shorter than gain runs. The 17-day century gain in 1995 holds that record.
ASI 2012 update 5: when graphs agree
During the melting season I'm writing (bi-)weekly updates on the current situation with regards to Arctic sea ice (ASI). Central to these updates are the daily IJIS sea ice extent (SIE) and Cryosphere Today sea ice area (SIA) numbers, which I compare to data from the 2005-2011 period (NSIDC ha...
Thanks, Bill, Rob.
2011 End Zone
Last year I wrote a series of five posts called End Zone, comparing different aspects of the final phase of the Arctic melting season in different years, to be able to predict a bit what those last weeks of the 2010 melting season could be holding in store. A lot of that ground work still stands...
Is anyone keeping an eye on global sea ice area or have the address to up-to-present Antarctic sea ice area/anomaly data? Thanks.
2011 End Zone
Last year I wrote a series of five posts called End Zone, comparing different aspects of the final phase of the Arctic melting season in different years, to be able to predict a bit what those last weeks of the 2010 melting season could be holding in store. A lot of that ground work still stands...
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