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No offense Viddaloo, but talking about ice-free 365 days is deeply unrealistic. Yes, the ice is in serious trouble. Yes the first complete summer melt-out (with "complete" still allowing for quite a bit of ice clinging to the CAA and Greenland shores) could happen in the 2020s, although the PIOMAS trend line would suggest more the late 2030s. But a year ice-free at the north pole (thankfully!) requires a lot more CO2 than we've yet released. It's just not a physically possible scenario under current conditions.
PIOMAS December 2016
Another month has passed and so here is the updated Arctic sea ice volume graph as calculated by the Pan-Arctic Ice Ocean Modeling and Assimilation System (PIOMAS) at the Polar Science Center: Well, November definitely was an Oh Jesus-month. Just like during October, the stall in sea ice exten...
I assume the deadline for submission was a few weeks back, but yeah, anyone whose estimate was over 5 is out of the running. 4.3 seems pretty likely.
2016 SIPN Sea Ice Outlook: August report
The third and last Sea Ice Outlook of this year has been published. The SIO is organized by the Sea Ice Prediction Network (as part of the Arctic research program 'Study of Environmental Arctic Change', or SEARCH), and is a compilation of projections for the September 2016 Arctic sea ice extent...
Hi KZ. I'm an infrequent commenter here, and I'm definitely not going to get into who said what about who ... instead, I'd like to ask you a pretty straightforward question. You said "I am not particularly concerned about the impact of global warming." My question is "Why not?" Possible answers could include, but are certainly not limited to (a) you believe we will soon curtail emissions, such that atmospheric concentrations (CO2+equivalents) never exceed say, 2x pre-industrial (b) you believe that the amount of warming from any given amount of emissions will be less than the central estimates given in the IPCC reports (c) you believe the actual effects of elevated temperatures on rainfall patterns, crop growth and sea level will not be harmful to most (or all?) human (and animal?) populations ...
I'll stop there. I don't wish to put words in your mouth, I'm just asking you to elaborate on why you don't think this is a big deal.
Thanks,
Greg
PIOMAS September 2014
Another month has passed and so here is the updated Arctic sea ice volume graph as calculated by the Pan-Arctic Ice Ocean Modeling and Assimilation System (PIOMAS) at the Polar Science Center: Last month I wrote: If this keeps up until the minimum, the 2014 melting season will have been excel...
Neven, what's the correct answer for an underground water tank - fiberglass?
Getting ready
With the melting season getting ready to go full speed, I'm also busy getting everything ready. First of all on the virtual level by updating the Arctic Sea Ice Graphs page. I've slightly altered the daily graphs page, by adding a couple of links, graphs and category names to make it easier to ...
Old Leatherneck, are you sure it was a toy *sailboat*?
http://en.wikipedia.org/wiki/Paddle-to-the-Sea
Research for a novel
Here's a question I received some time ago from a reader of this blog who is in the process of writing a novel. I thought it'd be a nice way to pass our time while we wait for the latest PIOMAS update. My answer is basically the either/or image on the right, but maybe you come up with other ide...
Well, during the winter, sea ice accumulates "from the underside". During melt season it mostly melts from the underside too, but also melts on the surface. Therefore, unlike on land where an object would progressively get buried deeper (in an accumulation zone anyway) I think an object on sea ice would tend to remain on top. Of course there's caveats - if the object is heavier than water, and the ice its on gets into a rafting event, the object could slide into the water (or get pushed in). So the question becomes how long a chunk of ice at the north pole in 1800 could survive intact without getting flushed out the Fram or winding up in a violent rafting event that tosses the object down a crack. Maybe a few cycles around the gyre? A few decades? Or postulate that that particular chunk gets rafted onto some basically immobile ice stuck to Ellesmere ... the object could still be there, although its odds are getting slimmer. One thing's for sure, it won't be anywhere near the north pole anymore. Just north of Ellesmere seems the only reasonable location.
Research for a novel
Here's a question I received some time ago from a reader of this blog who is in the process of writing a novel. I thought it'd be a nice way to pass our time while we wait for the latest PIOMAS update. My answer is basically the either/or image on the right, but maybe you come up with other ide...
3.8 million sq km
We don't generally get back-to-back records and this year is starting slow, but PIOMAS has the total volume lower than last year, so we're not talking "recovery".
Crowd-Source Prediction of Mean September Sea Ice Extent (July update)
Each June, July and August, the SEARCH Sea Ice Outlook (SIO) collects predictions for the mean extent of Arctic sea ice in September. These predictions come mainly from scientists but also some other people, drawing on a variety of modeling, statistical or subjective methods that each contributo...
A-Team, a couple of years ago the trouble with PIOMAS for "civilians" was that it was only gridded - it was popular demand that led them to put out a daily single summary number. I don't know what "extra" information was released that Wipneus and Chris used. Perhaps one of them can explain what it was that was beyond the normal PIOMAS output. Or maybe it was just the normal output, but the latest batch for March.
Erimaassa, maybe Neven is a fan of Eli. (http://rabett.blogspot.com/) :-)
PIOMAS April 2013 - extra update
The Polar Science Center has released some extra PIOMAS gridded data that allows smart bunnies like Wipneus and Chris Reynolds to show how ice thickness is distributed around the Arctic. Here's a thickness distribution map made by Wipneus that shows the difference between March 2012 and March th...
Donald, presumably Nevin doesn't want to pay for a real security certificate (which is only really needed if you're doing commerce of some sort). As said (but perhaps not well explained) in the post above, you can either create an exception in your browser to accept this, or use http instead of https.
Think of it like this: there are really three levels of security:
http - no security, your packets can be read anywhere along the path they take.
https without certificate - you get encryption.
https with certificate - encryption plus you're guaranteed the website hasn't been spoofed (which matters if it's a bank, but who is going to spoof Nevin's forum?)
Arctic Sea Ice Forum
The Arctic Sea Ice Blog is close to reaching the 25,000 comments-mark. Thanks to disappearing sea ice and great interest therein the blog was off to a flying start right from the very beginning, with traffic peaking last record melting season (especially when the cyclone hit). There is a clea...
Scarlet (freeway blogger), I just wanted to say I've been a fan of your work for years. It's brilliant.
Looking for winter weirdness
The Arctic is refreezing fast. Trend lines that were way below all other years for weeks on end have returned to the pack, as can be seen on the Daily graphs page of the Arctic Sea Ice Graphs website. Of course, there's still much more open water now than during the long-term average, and so we ...
I looked at CT this morning and suspected this post might be coming :-) Wow, what a year.
Record dominoes 12: CT SIA anomaly
The last record left this year has finally been broken (see them all on this page). Never since records began, has there been a larger anomaly from the 1979-2008 baseline in the Cryosphere Today sea ice area data set, as calculated by the Polar Research Group at the University of Illinois at Urb...
Nares strait is an interesting case this year. Peterman (2012) is making about 1 knot southbound (has just entered Kane Basin) but sea ice doesn't seem to be taking the same flow. The path of the giant berg is presumably indicative of the main current flow, but perhaps there's a surface wind or wind-driven current going northbound. The polynya in the Lincoln Sea would then be in-situ melt, or just pushed clear, from that surface current. Its shape certainly reminds me of the "bubble" that a light fluid jet can blow in a surrounding medium.
ASI 2012 update 10: (wh)at a loss
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 h...
At a rough guess, the albedo forcing from a 6 million sq km snow deficit for NH June would be significantly more than a 2 million sq km arctic ice deficit. However the snow deficit is shorter lived ... they are probably comparable over NH summer. Does anyone know if this has been well quantified?
The untold drama of Northern snow cover
Do we have time for another record while Arctic sea ice records are falling around us like ripe plums? I guess we'll have to make time. M. A. Rodger, who runs the Marclimategraphs page, sent me this guest blog concerning record snow anomalies: The untold drama of Northern snow cover When conside...
I changed my CT vote down one bin, so I'm going for 2.75 now. Probably conservative as CT currently has 2.92(!)
Polls August 2012
ATTENTION: new polls in the right hand bar, closing August 20th. I guess the latest SEARCH Sea Ice Outlook hasn't come out yet because participating forecasters want to see the full effect of this storm on the sea ice extent numbers before submitting their final estimate for the September averag...
I finally pulled the trigger on the August poll. 4.25 and 2.85, so I'm betting on two new records, but by small amounts. If a compaction event occurs I'll be quite a bit off though.
Polls August 2012
ATTENTION: new polls in the right hand bar, closing August 20th. I guess the latest SEARCH Sea Ice Outlook hasn't come out yet because participating forecasters want to see the full effect of this storm on the sea ice extent numbers before submitting their final estimate for the September averag...
Kevin, that's a very engaging review you wrote.
I found one tiny factual mistake you might want to correct - in the caption of the photograph of Barry Saltzman. Barry Saltzman died in 2001, at the age of 69, not in 1969.
2012 lower than all minimums before 2007
With more than a month left to go before the melting season ends, 2012 has already surpassed all of the sea ice area minimums preceding 2007 in the Cryosphere Today (Polar Research Group, University of Illinois at Urbana-Champaign) data set. Larry Hamilton's bar graph makes for an excellent visu...
Espen,
Not just by kayak. I believe a guy named Henry Larsen made that same left turn in 1944 :-)
ASI 2012 update 8: it shouldn't, but it does
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...
"Yep, the ground stays below sealevel all the way into central greenland basin. Similarly for ilulissat glacier"
That topo map from wikipedia disagrees. It's very close, and the map isn't a very high resolution, but it's the highest rez map of Greenland's bedrock elevation I've seen. So, is there a well-substantiated source for sea level channels to the central basin?
Petermann calves again
Petermann Glacier has calved another large ice island, about half the size of the calving of two years ago, which amounts to about two Manhattans. This is what it looks like: This second big calving (spotted this time by Arcticicelost80) is another spectacular event on Greenland this year, fol...
With the arch broken, looks like Kane Basin won't take too long.
http://lance-modis.eosdis.nasa.gov/imagery/subsets/?subset=Arctic_r03c02.2012183.terra.1km
Nares Strait 2012 Ice Arch Collapsing
It looks like the ice arch in at the southern end of Nares Strait has started to collapse, according to yesterday's satellite image from LANCE-MODIS: This break-up is occuring 10 days later than last year. Back then it took about two weeks for all of the ice to start moving across the entire s...
Thanks for that link Alberto. I was initially mislead by the first graph until I carefully read the captions of the first and second graphs to see precisely what they were showing. One caveat though - the second graph takes length of day into account, but it says "top of atmosphere", so the optical depth of the atmosphere may matter as WhiteBeard said. OTOH, scattering mostly just spreads the energy out - only a small amount is entirely back-scattered.
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...
Another big drop in the CT area measure. Air temps, cloud cover and ice distribution *appear* favorable for a continuation of this trend for a few days.
NSIDC Arctic sea ice news May 2012
Better late than never, here's NSIDC's latest analysis for the month of May. Most things are known to most of us, but I find the bolded excerpts towards the end very interesting: Arctic sea ice extent for May 2012 averaged 13.13 million square kilometers (5.07 million square miles). This was 4...
The last couple of days of the IJIS graph have me hearing Tom Petty.
(Free Falling...)
It's still probably less than a 50% chance to beat the 2007 daily low extent, but pretty close to. IJIS Area is dipping under the 2007 line. Uni Bremen on the other hand has 2011 extent lower than 2007 for today. It's all within minor weather fluctuations, so all we can really say is that the death spiral continues.
SIE 2011 update 18: ten yard line
During the melting season I'm regularly writing updates on the current sea ice extent (SIE) as reported by IJIS (a joint effort of the International Arctic Research Center and the Japan Aerospace Exploration Agency) and compare it to the sea ice extents in the period 2005-2010. NSIDC has a good ...
Heh, just because yesterday I noted the IJIS area graph for 2011 touching the 2007 area and seemingly ready to cross it ... today it flatlines with zero change in area.
Meanwhile IJIS extent seems determined to thread the needle between 2007 and 2008. Nonetheless, such low numbers in a year whose weather was nowhere near as favorable to melting as 2007's indicates further deterioration in the overall state of the ice.
Flash melting
I introduced the term 'flash melting' in a recent SIE update. It was a pun on the term 'flash flooding' where lots of rain falls out of the sky in a short amount of time, causing creeks and rivers to flood very fast. I based the concept on the state of large parts of the ice pack in the Beaufort...
Breaking: 2011 IJIS area falling below 2007 IJIS area.
http://www.ijis.iarc.uaf.edu/seaice/extent/AMSRE_Sea_Ice_Area.png
Not quite there yet, but pushing for a new record.
Flash melting
I introduced the term 'flash melting' in a recent SIE update. It was a pun on the term 'flash flooding' where lots of rain falls out of the sky in a short amount of time, causing creeks and rivers to flood very fast. I based the concept on the state of large parts of the ice pack in the Beaufort...
Twemoran, I agree on both points. Some days the crack in the Peterman is better resolved than others, but I'm not yet convinced it's widening. The Humboldt appears to be calving like crazy, with much of it coming from the side of that "bulge".
When I look at the ice in Kane Basin, it seems to me that there's two bands of it - a western band made of sea ice that's come down Nares Strait, and an eastern band that appears to be mostly bergs calved off the Humboldt. Anyone else see it that way?
Meanwhile Disko bay is pretty crowded with bergs from Jakobshavn Isbræ.
SIE 2011 update 16: flash melting
During the melting season I'm regularly writing updates on the current sea ice extent (SIE) as reported by IJIS (a joint effort of the International Arctic Research Center and the Japan Aerospace Exploration Agency) and compare it to the sea ice extents in the period 2005-2010. NSIDC has a good ...
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