Sea ice extent recovering quickly

Vincent. No. Why should something be wrong?
We have the anomaly (about 1979-2007) in the lower graph, which is now quite constant (was the next lowest since 1979, which we all knows). Watts graph shows the increase speed now is maybe the highest in 7 years but the anomaly graph shows that the increase speed was about as fast as the average since 1979. “Normal” years since 1979 the minimum ice extent has occured some weeks earlier than it did this year (even if this year was not late compared to the last 7 years, except 2007), and it’s more likely to have a maximum increase speed not so close to the minimum. So it’s extraordinary we already – so short after a minimum – have a 1979-2007 average increase speed (that’s the red almost flat anomaly curve).
You can e.g. compare the end points of the anomaly graph. Last autumn the anomaly figures falled until this date (which is consistent with Watts graph).
We ca also see that if we should have a recovery like last year we may almost reach 1979-2007 average ice extent level this winter!
Why some ppl think it’s so very important with more ice on the Arctic, and thus why this is an important topic I can’t figure out.
Anyway, the data from Illinois is consistent with Watts data. Explain why you think it may not. Maybe you next will time will find the answer by yourself if you are more specific in your question. That’s the best way of learning too. You ocan either have some confidence that things are right and challenge your though with an examination or – also good – think that something is wrong but try to falsify the data by a detailed examination which exactly points out the error. If you have point it out, then you can formulate the question here.
This was just a suggestion. I don’t even know if that above answered your questoin. Maybe it was something else which med you doubt about data consistency? If it was – or generally, in any way – I think you shall ask more specific questions…
I’m not at all meaned to be aggressive with this answer. It’s good to ask questions, but it’s hard to anwer too non-specific questions. Non-specific questions generally may be caused by no effort to analyze and no particular idea why the question is asked…

OT- 11.1% of the continental US is covered by snow this morning.
http://www.nohrsc.noaa.gov/nsa/
Well above the last two years… A feature of the site let’s you compare the last few years.

The baby ice is making a rapid comeback.
Without the burden of soot, I believe baby ice is more stable, plus, with its increased albedo would also tend to lower air temperatures, leading to even more ice.

“paminator (16:26:34) :
George E. Smith- Great post on arctic ice formation processes. ”
Paminator, I have to confess, that my “thesis” is largely a lot of handwaving and really high school level physics; I don’t work in this field; but I hoped to stimulate some discussion from those climate experts who do, and those who do understand what makes the ice cycle tick. I understand the thermodynamics quite well and also the optics. But from my seat of the pants opining it should be apparent that the melting and refreezing processes are anything but simple.
Gary Gulrud above gives 0.58 and 0.84 for water and snow, which truly are signigficantly different. Part of the reason is in fact optical. Open water, particularly sheltered amid ice, is a near optical surface, and the refractive index is quite low; about 1.33, so that makes the Brewster angle relatively small (53 deg). the Brewster angle arctan (n) is significant, because at that angle, the reflected component with the electric vector lying in the plane of incidence is totally extinguished, and the reflected beam is plane polarised perpendicular to the plane of incidence. So one polarisation goes to zero, anf the other about doubles. The result is that the total reflection coefficient is fairly constant (at about 2%) from normal incidence out to the Brewster angle, and then it rapidly increases to unity at grazing incidence. So the absorption of radiation beyond the Brewster angle drops rapidly because of the low index. In higher index materials, emission from the surface would be nearly Lambertian (cosine function), but for a low index optical surface like flat water it is less diffused.
Snow on the other hand is anything but an optical surface, and is more like an anechoic chamber walls, so the light capture by fresh snow, and the corresponding thermal emission is more likely to be isotropic, than even Lambertian, let alone more confined than that so the total emission can be quite different. However fresh snow rapidly degrades in reflectance, and snow only a few hours old has its reflectance drop to the 40% range for solar spectrum radiation. If I had to guess, I would say that what little soalr energy impinges on the snow, goes down in all those crystalline crevices, and cause local melting,a nd refreezing, so the internal crevices develop icy optical surface, that transmit the sunlight, into the deeper innards of the snow, where it really is trapped by the anechoic effect, so the reflectance drops once the fresh snow develops optical refrozen ice facets. 72 hout old clean snow, is not much differnt form ordinary grass in solar spectrum reflectance.
Some data on this stuff can be found in The Infra-Red Handbook ISBN: 0-9603590-1-X which was put together for the office of Naval Research, Defense Logistics Agency.
Atmospheric Infra-red phenomena have clear military significance for target detection and acquisition. The data may be a bit dated in some ways, but the amount of information in there is immense.
As for the melting of the ice, I referred to an interesting experiment, in my letter to Physics today published Jan 2005.
Here’s how it goes. You need a nice quiet preferrably moonless night in still air at zero C, somewhere in Michigan or Wisconsin area wher you can find a nice lake in winter, with floating ice sitting on basically zero degree water. Only apparatus needed is a stop watch, and a thermometer to determine that the air and water and ice are truly in the zero degree range. The night experiment is to be sure there are no extraneous energy sources anywhere near.
Part one of the experiment calls for stripping off all your clothes, and starting the stop watch , and then time how long it takes you to freeze, or at least cry uncle, and head for that hot rum drink. You do also need a pen and note pad to write down the elapsed time (well once your fingers thaw out).
Par two of the experiment is a repeat of part one of the experiment with one slight change; first you have to go and jump in the lake !
Well please do write and tell me your results, and state a brief conclusion about the relative heat transfer mechanisms of air and water.
So clearly (IMHO) the heat to melt floating sea ice, comes from the water that the ice is floating on; and not from the atmosphere. that 80 calories per gram of latent heat results in cooling an astronomical amount of sea water, and so long as the salinity is above 2.47%, the cooling water shrinks, so the sea level goes down; and NOT up or stay the same.
Measuring the emission from snow is not so trivial on the ground. I heard from one researcher who tried that at the South Pole, and basically he took his radiometer that he used to measure the solar insolation there, and simply turned it over and pointed it at the ground.
The problem is that to measure radiance or radiant emittance, you optically have to define both a solid angle of acceptance, and also a finite field of view in the object plane; that is you have to form a real image of the surface inside your radiometer, and an illumination or irradiation measurement that you use to measure the sunlight falling on the instrument, doesn’t have to form a real image of the source, so the optical arrangement for one is wrong for the other.
But I’m still embarrassed that I didn’t immediately grasp that Greenland ice falling off the land into the ocean does immediately raise sea level whether it melts or not, and whether the melted water refreezes in the arctic or not. It is an increase in total ocean mass after all; must be an early sign of Alzheimers.
George

I’m a pragmstist, not a scientist, I wish I had waited to unload all my winter woolies. I wonder if NSIDC can help out?

Symon wrote:
http://nsidc.org/images/arcticseaicenews/TimeseriesExplained.png
Why are they plotting 2008 ice extent against 2006 ice extent? Is it because 2008 against 2007 shows an increase?
Not quite. While they should be comparing the 2008-2009 transition against the 2007-2008 transition, their graph would be roughly the same given the data they’re using, which seems to be current to Jan. 8, 2009.