Guest post by Steven Goddard
In past years, NSIDC has referred to “declining multi-year ice” as the problem which the Arctic faces. Mark Serreze at NSIDC forecast a possible “Ice Free North Pole” in 2008, based on the fact that it had only first year ice. This year, multi-year ice has increased and NSIDC is now referring to declining “2+ year old” ice as the problem. Note the missing age group (2 year old ice) in the paragraph below from their latest press release .
First-year ice in particular is thinner and more prone to melting away than thicker, older, multi-year ice. This year, ice older than two years accounted for less than 10% of the ice cover at the end of February. From 1981 through 2000, such older ice made up an average of 30% of the total sea ice cover at this time of the year.
Due to the record minimum in 2007, it goes without saying that there isn’t a lot of three year old ice in 2009. Maybe next year they can raise the bar to 3+ year old ice, as the multi-year ice ages one more year?
Multi-year ice has increased from 2008, up to nearly 25%. Compare multi-year ice vs. last year’s map below – upper right corner.
http://nsidc.org/arcticseaicenews/2008/040708.html
The press has picked up on the 10% figure, based on the new higher standard NSIDC has set.
Ice older than two years once accounted for some 30 to 40 percent of the Arctic’s wintertime cover and made up 25 percent as recently as 2007.
But last year it represented only 14 percent of the maximum. This year the figure fell to 10 percent.
Note too that ice extent is nearly back to normal and has not declined significantly from the winter maximum.
Mike Bryant (16:38:41) I’m not sure about the discrepancy. The DMI pic is SST, the CT is ice. The white on the DMI pic is probably water or ice at or below 0 C. The projection of the two are different. Here is a picture with the outline of the DMI picture’s white area with a constant aspect ratio, scaled as best as possible to the CT picture. It does not fit well, however, I am surprised at how well the fit is in the northern Atlantic, assuming that was your area of concern.
On second thought, assuming these are highly accurate projections of measured areas by satellites that measure sub-millimeters, which, if either, is correct? http://i40.tinypic.com/29e4ye1.jpg
Another of the typical AGW misrepresentations: any change of a climate variable (no matter how complex) is due to, and only to, increasing temperature, caused by human CO2. A NASA JPL investigation of the 2007 Arctic ice minimum found winds and currents to be responsible for pushing ice out of the Arctic, where it melted in warmer water.
One of the things that amuses me about this subject is the claimed impact on polar bears, who hunt seals on the ice. Seals are, of course, mammals, who have to surface to breathe. To do so, they maintain breathing holes in the ice; the bears know this, and wait at the holes for a seal to surface.
Breathing holes are possible in first year ice (if maintained), but certainly not in multiyear ice. Much too thick, much too hard. Even USN submarines have difficulty surfacing through MY ice. That’s why the SSMI algorithms attempted to differentiate FY and MY ice (actually, pretty well). SSMI was a DoD instrument.
Bottom line, bearwise and sealwise: FY ice is good, more habitat; MY ice is bad, less habitat.
Thanks Steve,
Your projection answers my question about the North Atlantic.
Mike
O/T, but the post on watts about synchronized chaos made me think about this. Is it possible that CO2 and temps synchronized, and this turned on a natural cooling mechanism? Runaway warming suddenly halted by natural negative feedbacks?
Sorry, meant ‘warming REVERSED’ not halted.
Jack Green (18:00:54) :
I guess all this depends on how you define ice. Ice is frozen water. Old ice takes as much energy to melt as new ice.
Not when it’s frozen saltwater.
Mike Bryant (16:38:41) :
At this site:
http://ocean.dmi.dk/satellite/index.uk.php
Choose “Arctic Ocean” on the pull down menu under “Geographical Domain”
Then compare the Sea Ice to the picture at CT here:
http://arctic.atmos.uiuc.edu/cryosphere/
Now, why is there such a discrepancy?
What discrepancy?
http://ocean.dmi.dk/arctic/satellite/index.uk.php
http://i302.photobucket.com/albums/nn107/Sprintstar400/arcticseaicecolor000.png
Apart from the different projection.
Tom in Texas (18:56:57) :
In addition to “Quote of the Week”, how about “Comment of the Week”?
I nominate Mike Strong (18:24:21) : Letter to Walter Meir
I nominate this post as “Joke of the Week”
Among the various howlers is the following which was already explained to him on this site!
To me, an old ice cube in my freezer, if frozen completely, is pretty much the same as a new one. And indeed, in the winter of 2007/2008, there was a surprising recovery of sorts. And this winter (2008/2009) there was even more of a recovery than last year in the Arctic. The decline was listed as -11% per decade last year, and now MAGICALLY, it is now only -2.7% per decade on your trend charts. On the other side of the Earth, the Antarctic is now trending up at +4.7% according to your monthly charts, and just a month ago it was only +2.8%.
The MAGICAL part of course arises because Mr Strong confused monthly trends with annual trends.
If it’s still minus 40 in the Arctic how could the maximum extent of ice be Feb 28? Or is Feb 28 just an arbitrary date chosen for the end of winter ice maximum?
Harold Ambler (19:14:34) Canada temps
http://www.weatheroffice.gc.ca/canada_e.html
I’ve been using this site to keep track of the cold across Canads.
Scientist Hillary Clinton offers hope that the US can fix the Arctic overheating problem which the Catlin explorers are suffering.
http://www.washingtonpost.com/wp-dyn/content/story/2009/04/07/ST2009040700783.html
Isn’t it great living in an insane asylum?
Justin,
Winds in the Gulf of Okhotsk have compressed the ice, causing a slight dip in extent. That is what is meant by “the start of the melt season” – while ice in the Arctic basin is of course getting thicker at -30C.
Phil. (19:47:51) :
Explain what you mean by “different projection.” I assume what Mike was referring to was the difference around Greenland and over Russia, but I don’t know much about reading these images.
Steven Goddard (20:18:12) :
Justin,
Winds in the Gulf of Okhotsk have compressed the ice, causing a slight dip in extent. That is what is meant by “the start of the melt season” – while ice in the Arctic basin is of course getting thicker at -30C.
Unfortunately for that hypothesis the ice area has also dropped there, more likely due to higher SST’s (the PDO).
http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/recent365.anom.region.14.html
OT where did La Nina go? http://www.osdpd.noaa.gov/PSB/EPS/SST/data/anomnight.4.6.2009.gif
not much of a cold flow anymore! The PDO seems to be in charge?
Phil. (20:34:25) :
It looks like Okhotsk is the primary source of ice area loss. Other areas are growing and retreating still to make a near zero sum total. (looking at IceCap).
The PDO is keeping Okhotsk colder than normal I think.
“Isn’t it great living in an insane asylum?”
I wouldn’t quite call it insane. More like an “idiocracy”. We have reached a point where “the truth” is whatever validates your own opinion or the opinion of the social group you wish to identify with. Now if some of the really major music and film celebrities came out and said it was all a load of hooey, you would suddenly find the masses changing their opinions too because they want to be like the “cool kids”. Reality doesn’t matter to these people.
Tim McHenry (20:25:11) :
Phil. (19:47:51) :
Explain what you mean by “different projection.” I assume what Mike was referring to was the difference around Greenland and over Russia, but I don’t know much about reading these images.
As also pointed out by Steve K (below) Mike was comparing images of different quantities, I gave the corresponding image from the same source which matches extremely closely with cryosphere today image. The maps were produced with different projections (as did Steve K), meaning that a different algorithm for transforming the image of a sphere onto a flat surface.
Steve Keohane (19:20:06) :
Mike Bryant (16:38:41) I’m not sure about the discrepancy. The DMI pic is SST, the CT is ice. The white on the DMI pic is probably water or ice at or below 0 C. The projection of the two are different.
Steven Goddard wrote:
“The Arctic always loses a lot of ice to wind blowing towards the North Atlantic – that is why there is never much ice more than five years old.”
Younger, thinner ice is more susceptible to being pushed around by winds than older, thicker ice.
I see images of Nuclear Submarines in the 1960’s busting up through the ice in the Arctic, so looking at the graph, it’s never been that thick.
The Caitlin Cruisers are frostbitten and exhausted, but oh that ice is so melting at -35C. The Sun is like a blowtorch up there in April, don’tch know.
Arn Riewe wrote:
“AGW implies the loss of ice is higher arctic temps. What I have seen recently would say that no – it’s more wind and/or currents that are affecting ice levels.”
Or maybe a combination of both? First year ice is thinner and therefore more easily moved around by winds than is old ice.
Bill Illis:
“The NSIDC just seems like a closed organization to me and will not open their data for general public review.”
Have you gone to their website and tried to download it? I just did, and it only took me a minute or 2 to find sea ice data through April 6.
” Robert Bateman (21:06:25) : ”
My understanding is that it isn’t all that unusual for the North Pole itself to be ice-fee in the summer. It depends on which way the winds blow what remains of the sea ice. It isn’t just going to sit there at the pole, it is going to drift with the wind. I believe someone posted pictures here (or maybe it was at CA) of submarines surfacing at an ice-free pole many years ago.
Robert Bateman (21:06:25) :
I see images of Nuclear Submarines in the 1960’s busting up through the ice in the Arctic, so looking at the graph, it’s never been that thick.
They had to pick their spots, usually refrozen leads.
A bit like this one: http://www.youtube.com/watch?v=6uwE9MCfzMI
Multi-year ice has increased from 2008, up to nearly 25%.
1985 was 50% ,,,, 2009 looks good for 25% ,,,,2008 looks good for 20%
Arn Riewe (13:48:03) : where you see 30% ????
At current recovery of 5% per year
20% at 2007 that means in 6 years there will be 50% Multi-year old ice, 2013-2014.
WE shall see.
When we had the NSIDC sensor problem, Dr. Meier was kindly answering a few questions but stopped short of discussing the key points: 1) why does NSIDC use a 20 y average for sea ice extent? Especially now while it uses a 30 y average when it comes to ice thickness? 2) Since multiyear ice is really not that old and that back in 1980, it only comprised according to NSIDC 30% of the arctic sea ice, what happened to the 50, 100y old ice? Of course it melted which suggests that at any moment the amount of multiyear ice is never a huge proportion and thus the alarmism displayed is just the result of these scientists observing for the very first time these events with a scrutiny never achieved before. 3) The clear relation with atmospheric circulation and in particular for those who have read Marcel Leroux and his students works, the entire premise of alarmism becomes a moot point and if anything highlights a rather simplistic vision of climatic changes and/or an agenda.
“Sea ice thickness has been hard to measure directly, so scientists have typically used estimates of ice age to approximate its thickness. But last year a team of researchers led by Ron Kwok of NASA’s Jet Propulsion Laboratory in Pasadena, Calif., produced the first map of sea ice thickness over the entire Arctic basin.
Using two years of data from NASA’s Ice, Cloud, and land Elevation Satellite (ICESat), Kwok’s team estimated thickness and volume of the Arctic Ocean ice cover for 2005 and 2006.”
http://www.jpl.nasa.gov/news/news.cfm?release=2009-062
So its an “estimate” of thickness a not direct measurement. wonder how accurate it is.