Sea ice extent recovering quickly

Watching ice melt was fun. Watching it re-freeze has to be equally fun.
So, I’ve invited people to place bets about the value of the Nov1-7, 2008 average in comments in this post. The winner gets brownies (provided they live in the lower 48. Other rules apply.)

You know, it just occured to me to flip the graph upside down. I do believe that would pretty well match up with the way sea water warms during the summer in the north. Having spent much of my teen summers at Misquamicut and Watch Hill Rhode Island, I can tell you that the water there is always warmest in late August and September. Perhaps that is the reason the sea ice is at it’s lowest in those months. Warmer water, less ice.

The Arctic is losing heat very efficiently.
Think about what is occurring – massive amounts of water are changing over to ice by losing heat to the air and by radiation – more heat per unit of mass of water than that required to heat the water to near boiling.
I wonder what the theoretical highest slope of that curve could be?

Well, if it keeps going at this rate it will have fully recovered in early November. Then it can spread over Canada and Siberia… 🙂

From your animation last week
http://wattsupwiththat.com/2008/10/03/winds-are-dominant-cause-of-greenland-and-west-antarctic-ice-sheet-losses/
it seems apparent that most of the oldest multi-year ice is lost when it gets pushed southward along the east coast of Greenland. I believe that NSIDC also said that the amount of first year ice that survived this year’s melt was a record high amount. This should help to begin to replenish, over the next few years, multi-year ice, assuming this trend persists. The current NSIDC graph is also showing rapid increase in sea ice extent. Should be interesting to see how this year’s freeze compares to last year’s event.
There’s almost more activity and changes apparent in the Arctic than on the sun’s surface.

Is the steep rise an indicator of the 12 month plus lag between ENSO events and peak Arctic response? It would be tough to tell with all the other factors that impact the Arctic.

I suspect that the MSM is going to stop calling for coal-fired power plants to be shut down as soon as it is realized how bad this Northern winter is likely to be.

Looking at the very cold NCEP forecast for the next two weeks, it is safe to expect that the rapid pace of ice growth will be maintained.
http://wxmaps.org/pix/temp2.html

what is interesting is the steep shape of the 2008 curve compared to the other years which are more wide in form. Can it keep up this path I wonder?

The graph shows similar behavior in the other traces, i.e. a “rapid” increase in October and then a shoulder in early November followed by a lower growth rate into December. But then again I maybe the only one that is seeing this.

REYKJAVIK, Iceland – Iceland suspended trading on its stock exchange for two days and took control of the country’s largest bank — the third to be placed under its protective umbrella — on Thursday as it grappled with a banking crisis that is threatening to engulf the entire country.
See, Global Warming has caused Iceland to almost go under…..can we bail them out?

Why is the period 1979-2000 average used for comparison? What is so magical about this period’s endpoint?

Shhhh!!! This is a secret!
The media has been running Ice Loss stories all week and other useful stories about Polar Bears.
The latest and my favorite one is researchers are testing polar bear hearing so they can say the noise of human activity in the Arctic effects the survivabilty of the bears by impacting their ability to hunt.
They are doing this with a captive bear who they have trained to click a switch when it hears a noise to get a treat. Perhaps training a bear to do tricks for food might actually impact its ability to hunt, I am just saying.

Frank K. Yep, good news! Ice bears now wont die or become deaf:
http://wattsupwiththat.com/2008/09/30/bs-alert-polar-bear-hearing-affected-to-due-global-warming/
I’m no psychologist, but also the penguins seems just fine…
http://a448.ac-images.myspacecdn.com/images01/117/s_802e9571ee87157070e6a60da322ec9f.gif
Well, I bet media (and the regulating left) come up with something!!

Gahhhh….. Global warming melts Icelands financial systems – stop Coal now!!!

Record cold data is beginning to role in:
These data are preliminary and have not undergone final quality control by the National Climatic Data Center (NCDC). Therefore, these data are subject to revision. Final and certified climate data can be accessed at the NCDC – http://www.ncdc.noaa.gov.
Record Report
000
SXUS76 KPDT 091815
RERPDT
RECORD EVENT REPORT
NATIONAL WEATHER SERVICE PENDLETON OR
1114 AM PDT THU OCT 9 2008
…NEW DAILY RECORD LOW TEMPERATURES FOR OCTOBER 9TH…
NOTE: STATIONS MARKED WITH * INDICATE THAT THE STATION REPORTS ONCE
PER DAY. FOR CONSISTENCY…THESE VALUES ARE CONSIDERED TO HAVE
OCCURRED ON THE DAY THE OBSERVATION WAS TAKEN BUT MAY HAVE ACTUALLY
OCCURRED (ESPECIALLY FOR MAX TEMPERATURE) ON THE PREVIOUS DAY.
STATION PREVIOUS NEW RECORDS
RECORD/YEAR RECORD BEGAN
MEACHAM, OR 24 / 2006 20 1948 :SINCE MID
See!!!! It’s damn cold where I live!
Damnable global warming.

Remember the definition they use for extent: a region is considered part of the extent if at least 15% is covered. So you could easily have a large region that is at say 14% and it wouldn’t be considered part of the extent. A 1% increase in the ice in the region and voila the region is part of the ice extent. A further increase of ice in that region wouldn’t increase the extent by that definition only the actual ice area. Other years have shown similar bumps in extent trends. I posted this graph over at Lucia’s.
One thing to note is that 2008 has been above the 2003-7 average extent increase for about a month.

@ Pamela Gray (18:27:37) :
“Studded tire season isn’t till November 1st. But this Friday and very early Monday morning, I have to navigate snow covered roads over Tollgate on my way to the ranch. Damnable global warming”
Be thankful for AGW. Could you imagine how bad it would be without it ? ; )

@Dee
I can see it now:
“Mann announces website Watts Up With That (www.wattsupwithtat.com) causing global warming. The website has been growing enormously in page-hits this year, causing servers and personal computers everywhere to use more electricity as thousands of web-browsers land on the page, many of them by bloggers who link to the page causing further traffic. John Smith, a university professor who teaches classes in the environmental impact of technology upon nature, said that “the extra usage of electricity, resulting in increased CO2 production, may result in increased global warming causing computers to shut down due to overheating.” The professor said he strongly encouraged people to turn off their computers, stay home, and pray the Earth does not explode due to greenhouse gas emissions. He cited with concern a graph put out by famed statistician Michael Mann correlating traffic on the website with an increase in greenhouse gases and consquent temperature rises globally. Mann remarked himself that he hoped local officials would contact site operator, Anthony Watts, to urge him to set limits on his page hits in order to make it more environmentally friendly. Site operator Anthony Watts could not be reached for comment, although – honestly – nobody really tried anyway.

sorry about the typo…should be (www.wattsupwiththat.com)

@JohnD…
Cross the equator???
It’s obviously going to run out of water before it gets that far… Isn’t it?

Studies of Vostok and Greenland ice cores show that the Dow Jones lags the AMSR-E graphs by about three months.

with such a quick recovery the average extent in 2008 should remain not only above 2007, but also above 2006 and 2005.
Probably even arctic ice albedo of 2008 may remain above the years.

Anthony,
Here is the text of my email to Richard Black, the BBC Environmental Correspondent, a copy also being sent to Dr. North, who is an avid supporter of your work. http://eureferendum.blogspot.com/
“Dear Mr Black,
Reference your email of 17th September, Anthony Watts has posted an update on Arctic ice. I would especially draw your attention to Anthony’s warning:
“I’m not one to read much into this, as to do so would be to make the same mistake as was done earlier this year when the NSIDC melt trend led one researcher there to conclude that we’d see an “ice free north pole”. http://wattsupwiththat.com/2008/10/09/sea-ice-extent-recovering-quickly/
However, you will see that, inexplicably, the sea ice appears to be recovering at a rapid pace. There are many opinions in the comments section as to why this is happening and perhaps you will have something to say about this in your BBC slot.
Yours truly,
Perry Debell
—– Original Message —–
From: Richard Black-Internet
To: PERRY DEBELL
Sent: Wednesday, September 17, 2008 10:35 AM
Subject: RE: Arctic Sea Ice Melt Season Officially Over; ice up over 9% from last year « Watts Up With That?
Dear Mr Debrell,
Thanks for your email. It’s always nice to see when people have access to what they know to be the unvarnished truth, with no room for doubt.
Best wishes,
RB
——————————————————————————–
From: PERRY DEBELL [mailto:cd014j7257@blueyonder.co.uk]
Sent: 17 September 2008 09:13
To: Richard Black-Internet
Cc: EUREFERENDUM@aol.com
Subject: Arctic Sea Ice Melt Season Officially Over; ice up over 9% from last year « Watts Up With That?
Dear Mr Black,
From Anthony Watt’s website, wherein he explains the unvarnished truth about global temperatures.
“Though it appears NSIDC is attempting to downplay this in their web page announcement today, one can safely say that despite irrational predictions seen earlier this *year, we didn’t reach an “ice free north pole” nor a new record low for sea ice extent.”
http://wattsupwiththat.wordpress.com/2008/09/16/artic-sea-ice-melt-season-officially-over-up-over-9-from-last-year/
* I wonder who was doing that? Was it Richard Black, Environment Correspondent?
http://news.bbc.co.uk/1/hi/sci/tech/6610125.stm
BTW, I read your latest contribution this morning. Spin as much as you like Mr Black, you and your contacts are fighting a losing rearguard action against the reality that our planet’s temperatures are ultimately controlled by the warmth from the sun. It occurs to me that you personally should now be publically reconsidering your position on AGW, don’t you?
Yours truly,”

The BBC will probably start showing repeated re-runs of
The Day after Tomorrow if this winter is bad. There is already a BBC Ethical Man to show us how we should live our lives.
http://news.bbc.co.uk/1/hi/programmes/newsnight/ethical_man/default.stm
Britain is at the end of the gas pipeline from Russia, if this winter is particularly cold there might not be enough getting here after the rest of Europe has taken what it needs. I think they’ll have to shut down the gas powered electricity generators to ensure supply to the voters. Might be interesting.

Indeed lower global temperatures helped saving the arctic ice this year since the sea ice in arctic correlate well with global temperatures.
Just look at the extreme La Nina 1998 and how the ice just melted away in no time that year.
http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/current.area.jpg
Hmm, on a second thought, the El Nino in “the warmest year in a millenium”, 1998, isn’t even visible in the arctic sea ice area record. The change in tempearature upwards 1998 was a lot bigger than the drop this year.
Obviosuly the correlation global temperature and arctic ice area isn’t that tight that you can explain changes in ice area from just global temperatures.

Jerker. Good points. You’re right about the annual record, but also there may be multidecadal trends which is correlates with temperature. The very late 70th had the largest ice extent on record (which started then…), and in the 40th the ice extent may have been lower than after a warm period (it was a fuzz in media about the Arctic ice melting then). The ice retreat the last 30 years was during a warm period in the PDO.
So I think there most likely are multidecadal trends as well as annual patterns of losses and gain. Thus losses are statistically more likely during a warming phase, which means there are an over time temperature-ice correlation.
The large summer 2008 losses may have been due to thinner ice after a multidecadal trend — as well as or mostly due to wind and sea current patterns — and I think it’s not completely wrong to have the hypothesis that this year may have marked the beginning of a a shift in a trend due to PDO, which indeed controls the temperaturee on the northern hemisphere. I guess we would say so even if the supposed shift in the trend is also controlled by other more arbitrary year-by-year patterns…
Also any little ice age gives increasing Arctic ice of course — not any particular year though, but I would bet that very cold years correlates in some respect with increasing ice, just as trends in the PDO shift would indicate.
I’m no climate scientist. 🙂

Funny how last yar the comments on this blog were about the Antarctic ice sea ice, not a mention above but lets put the record straight, think global. http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/global.daily.ice.area.withtrend.jpg
As you can see the global sea ice area is around 2,500,000 square km below the mean.
Seeing as you guys have forgotten about the Antarctic, just thought I’d remind you!
On a seperate topic just thinking what China is going to do with its $1.2 trillion in US bonds, will they be the communist white knight to save the capitalist system from collapse by investing in stocks… or will they be the typical communists and destroy the capitalist structure by ‘cashing in’ the bonds. Interesting and worrying stuff.

Think soot. Once the ice melts, all the soot that was accumulated during the past year is dissolved in the ocean.
There’s a bit more to it than that. Ice that doesn’t melt completely will accumulate a layer of soot on its surface in summer over a number of years. The soot will progressively increase the summer melt until the sea ice melts completely and the soot goes into the ocean. At which point the soot accumulation begins again.
If soot is the (or even a) major cause of sea ice melt, then we should see cycles of a number of years of sea ice decline, a spike down to the summer minimum, followed by a rapid increase over over a smaller number of years, which is what the few years prior to this year looked like.
http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/seasonal.extent.1900-2007.jpg
Note how the spike down is a summer phenomena, which is what a soot accumulation model would predict.

You know, Perry, that really is a powerful email. The juxtaposition of ‘unvarnished truth’ and ‘no room for doubt’, along with the sullen tone, makes me wonder if our dear Richard Black hasn’t suffered from a little introspection lately. If not, it’s wonderfully grand example of the sort of unconscious irony that flows like a stream in flood from cognitive dissonance.
===============================

‘ScienceDaily (Oct. 10, 2008) — Researchers from TU Delft joined forces with the Center for Space Research (CSR) in Austin, Texas, USA, to develop a method for creating an accurate picture of Greenland’s shrinking ice cap. On the strength of this method, it is now estimated that Greenland is accountable for a half millimetre-rise in the global sea level per year.’
http://www.sciencedaily.com/releases/2008/09/080930081355.htm

“As you can see the global sea ice area is around 2,500,000 square km below the mean.”
Yours is not yet established.

Gary Gulrud (08:35:03) :
“Yours is not yet established.”
“Your customary sagacity is noted.”
Amongst all the stodgy discussions above your pretentions of interest are a breath of fresh air! 😉

@Perry Debrell (& Dodgy Geezer)
I find it remarkable that the BBC are able, apparently without shame, to carry this week a June 18th report by Richard Black “Arctic sea ice melts even faster” and apparently no mention of any more recent information. I also find Richard Blacks’ reply to Perry Debrell extremely sarcastic and insolent. Clearly he is rattled. Don’t let them off the hook (Black & BBC) and don’t loose your cool – that would only play into their hands.
Thomas G

“Austin (15:25:10) :
The Arctic is losing heat very efficiently.
Think about what is occurring – massive amounts of water are changing over to ice by losing heat to the air and by radiation – more heat per unit of mass of water than that required to heat the water to near boiling. ”
The latent heat of freezing for water is roughly 80 calories per gram; which is enough to raise ice water to 80 deg C. Not exactly near boiling; but not a bad image anyway. The latent heat of evaporation is even more impressive; 595.4 cal per gram at zero C, and maybe 1-2 cal more than that for lower temperature salt water.
The arctic will be very low humidity, so open water should evaporate readily even though the saturation vapor pressure is only about 4.5 mm of Hg. But remember that it is the higher energy molecules that are emitted by the surface, so the surface cools with the evaporation. Water is the most opaque known liquid for long wave IR radiation, so the surface near zero C must emit almost like a black body with about 97% emissivity. The peak of the specral radiant emittance is shifted a few percent to about 10.65 microns, from the 10.1 at the mean earth temp of 15C. the black body emission at 15C is around 390 Watt’s per square meter, but it is only 315 at zero C, because of the 4th power relationship.
I’m not sure of the exact dynamics of the refreeze process, but I suspect that evaporative cooling of the surface starts the process, and then once you have some ice presence, the albedo effect kicks in and reflects sunlight, so the captured insolation now drops ,letting the ice cool and also the air temperature cool. the evaporation becomes sublimation from the ice, once it is thick enough and the air temperature should drop faster. I don’t have time to calculate what the heat loss (rate) due to evaporation/sublimation is but eventually radiation and conduction dominate the cooling. certainly it should accelerate once icing has started, and the earlier it starts, the higher the sun angle, so the greater is the reflective effect of the ice in terms of watts reflected. Eventually at lower sun angles the grazing incidence reflectance is higher, but the Watts per m^2 is less.
Very interesting process, with all knids of fancy optical processes going on besides the thermodynamics.
George

Mary,
It looks like we should have been more worried about the SH in the 1980s.
http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/current.anom.south.jpg
Smaller positive anomalies, larger negative anomalies. What’s your opinion?

Re Don Shaw’s query about methane. I would think the Arctic has always been disgorging methane, as permafrost regions melt. But as the permafrost melts you also get accelerated plant growth further north in the arctic, which can soak up a lot of extra CO2. And if tropical forests are being cut down at a fast clip (bad thing), the methane emissions from decaying rain forest detritus will get less, so maybe offset some arctic methane. And maybe permafrost melt is about to stop.
NOAA shows that out of 390 W/m^2 average (15 deg C) earth IR emission, only 40 W/m^2 escapes through an atmospheric window. So allegedly 90% is already captured by GHG. So just what is there for more merhane rto grab.
I thought that methane was unstable in the sun drenched atmosphere and quickly becomes CO2 and water.
And if enough methane gets loose; it is a perfectly good fuel so we’ll mine it. What about all the methane from oil wells that is just flared off, why not start capturing that.

Bill Illis (18:07:51) :
“Has anyone seen any evidence that the summer of 2008 was colder than 2007 in the Arctic. All of the data I have seen does not show this.”
Let’s try plain text.
http://vortex.nsstc.uah.edu/public/msu/t2lt/tltglhmam_5.2

Alan Caruba has a blog in which he mentions that Joe Bastardi, the Chief Long-Range Forecaster at AccuWeather, has released his 2008-09 Winter Season Forecast addressing issues of average temperature and precipitation that will impact the nation.
http://factsnotfantasy.blogspot.com/2008/10/cold-and-colder.html
His forecast calls for one of the coldest winters in several years across much of the Eastern portion of the United States, the population-dense third of the nation. The northern Rockies and Northwest is predicted to have more snow than normal, though not as much as last year when the snow pack reached twice normal levels. In the East, however, he anticipates a lot more snowfall than last year.
I find AccuWeather rather like the Curate’s egg, especially when it come to their Brett Anderson. He censors comments, well he censored mine some days ago in which I stood up for falling temperatures, so to speak.
His latest article of October 10, 2008, “Alarmist and Denier Scientists” should be read in order that my comment reproduced below is seen in context, as I do not think it will see light of day over there.
“Well, well, well, you could not find a more recent article than LINDZEN, Wednesday, April 12, 2006? Please allow me to assist you with “Climate Science: Is it currently designed to answer questions?” LINDZEN September 27, 2008.
Abstract
For a variety of inter-related cultural, organizational, and political reasons, progress in climate science and the actual solution of scientific problems in this field have moved at a much slower rate than would normally be possible. Not all these factors are unique to climate science, but the heavy influence of politics has served to amplify the role of the other factors. By cultural factors, I primarily refer to the change in the scientific paradigm from a dialectic opposition between theory and observation to an emphasis on simulation and observational programs. The latter serves to almost eliminate the dialectical focus of the former. Whereas the former had the potential for convergence, the latter is much less effective. The institutional factor has many components. One is the inordinate growth of administration in universities and the consequent increase in importance of grant overhead. This leads to an emphasis on large programs that never end. Another is the hierarchical nature of formal scientific organizations whereby a small executive council can speak on behalf of thousands of scientists as well as govern the distribution of ‘carrots and sticks’ whereby reputations are made and broken. The above factors are all amplified by the need for government funding. When an issue becomes a vital part of a political agenda, as is the case with climate, then the politically desired position becomes a goal rather than a consequence of scientific research. This paper will deal with the origin of the cultural changes and with specific examples of the operation and interaction of these factors. In particular, we will show how political bodies act to control scientific institutions, how scientists adjust both data and even theory to accommodate politically correct positions, and how opposition to these positions is disposed of.
http://arxiv.org/ftp/arxiv/papers/0809/0809.3762.pdf
Mr Anderson, you do yourself no favours by being deliberately obtuse and economical with the truth in your assertions that what little beneficial warmings this planet had during the 1980s and 1990s were down to human causes. You may as well accept that you are wrong, apologise to your readers and hope against hell you hang on to your job.
Whilst you have the time, please read all 36 pages of LINDZEN’s work at Massachusetts Institute of Technology.”

Tamara (13:37 ) Without commenting on the amplitude of the anomalies, NH and SH sea ice tend to run in opposite directions because Antarctica temps tend to run in the opposite direction to the rest of the globe, discussed in “The Chilling Stars.” Some have called it the sea-saw effect, but Svensmark calls it the Antarctica Anomaly, and is a result of cloud cover, not CO2, nudging the climate, by his theory.

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.