People send me stuff.
Today, just over two months away from the end of summer, when NASA’s Jay Zwally famously predicted (with an assist from AP’s Seth Borenstein): “…the Arctic Ocean could be nearly ice-free at the end of summer by 2012″ and we are nowhere near that becoming true, I get sent a contest being solicited by the people who run “Vision Prize” in San Francisco. I had to chuckle at this.
CALL FOR PARTICIPATION: When will the Arctic Sea become free of summer
floating ice?
Dear Climate Scientist,
You have probably already seen the cover story of last month’s Economist on the Arctic: The vanishing north. The Vision Prize [online poll of climate scientists](http://visionprize.com/) is currently asking this related question:
**When (if ever) will the Arctic Sea become completely free of summer floating ice?**
Please [Sign Up](http://visionprize.com/users/new) now to submit your prediction and join [more than 200 of your colleagues](http://visionprize.com/participants#expertise) participating in this new climate risk communication project. Participation is free and takes just a few minutes. Thanks in advance for your support.
Vision Prize is affiliated with researchers at Carnegie Mellon University and the University of Minnesota Institute on the Environment, and is strictly nonpartisan.
Vision Prize | Box 7775 #20915 | San Francisco CA USA | 94120
===============================================================
The bottom of the original email allows the recipient to forward to a friend, so by doing so they make this a contest open to everyone.Lest some of our vocal detractors cry “foul” I’ll point out this entry in their “roster of experts“:
Glenn Tamblyn
Skepticalscience.com; (Australia); Licensed professional engineer – commercial; Mechanical Engineering; Industry – Other;
Dana Nuccitelli
Tetra Tech, Inc.; (United States); Other scientific or technical – commercial; Environmental Science, Physics; Industry – Environmental Services; climate science
Apparently, they’ll take anonymous predictions too:
puffycloud
University of Washington; (United States); Graduate student; climate variability and change; Academia – Earth Sciences; atmospheric science
They want predictions, so let’s give them some, signup here:
Please [Sign Up](http://visionprize.com/users/new) now to submit your prediction
I signed up, and the confirmation email to activate my account went immediately to SPAM, so you may have to fish it out of your own account.
Even though they’ll let members of a blog that revises history on a regular basis and treats professional scientists with unprofessional attacks and anonymous grad students in, apparently, they don’t just let anybody in. Only the anointed perhaps? This is what I got:
They are heavily weighted with UW and other faculty, according to their online live profile:
It will be interesting to see if they are biased or open and whether I get to join the “players”.
I urge WUWT readers to sign up and report your acceptances or rejections below.
kadaka (KD Knoebel).
PIPS 2.0. now defunct.
It would be interesting to compare how PIPS 2.0 ( a model) would have compared in 2012 to other models (PIOMAS) and then on to models of observations. ( Cryostat)
I would not make too much out of 1 years worth of observations. with PIPS 2.0 gone, I guess you’ll never know.
However, if you believed PIPs ( a model ) and used a model ( linear regression of the last 10 years of data) to predict the time when september volume reaches zero. it would be 2026.
So, like I said. 2020 is the over under line for Ice free ( area in sept < 1million sq km)
2020: smart money says take the under bet.
There are various factors affecting Arctic sea ice. But CO2 is not one of them. And “carbon” is what all the arm-waving is about, no?
The natural decline in Arctic ice has happened before. Repeatedly. The alarmist crowd is grasping at the ‘Arctic ice decline’ straw like a desperate drowning man, because that’s all they have left to alarm the populace with. Every other scare has been debunked: the tropospheric ‘hot spot’, two-headed frogs, increasing hurricanes, floods, droughts, etc., etc. Everything observed today has happened in the past, when CO2 was much lower — and those historical extremes reached a far greater extent than the very *mild* temperature changes over the past 150 years; 0.8ºC is nothing over a century and a half.
Unless and until someone can provide testable evidence showing that Arctic ice cover is a function of human CO2 emissions, Occam rules: the simplest explanation is most likely the correct explanation. Wind, changing ocean currents, and similar natural causes are the reason for the recent decline. CO2 has nothing to do with Arctic ice cover.
Prove me wrong.
Smokey.
You havent made a testable statement. when you formulate a testable hypothesis, then you have the possibility that someone can disconfirm your hypothesis.
Other points.
1. Occam’s razor is not science. It is a pragmatic rule.
2. Arguing that wind and currents is “the cause” is not a hypothesis. for that you need actual numbers.
Arguing that c02 has nothing to do with ice cover is not a meaningful, scientifically meaningful or measurable, claim. You really need to study the structure of scientific sentences or claims.
But lets start with something simple. If warmer water flowed into the arctic in 1936, for example, would you expect the ice to melt more or less than if colder water was flowing in?
You do know that the currents and wind seen in 2007 have occurred before without any great ice melt. by your logic they cant cause melting. oh, by the way. wind doesnt cause ice to melt.
Wind can compact ice. Wind can move ice to places where warmer water cause the ice to melt, but wind, in an of itself, doesnt melt ice. You realize that really strong wind blows in the antarctic.
And ‘current’ doesnt melt ice either. it moves ice, but doesnt melt it. ice would be melted by….
adding heat.
Steven Mosher,
You want a testable hypothesis? I got yer testable hypothesis right here:
At current and projected concentrations CO2 is harmless, and beneficial to the biosphere
Have at it.☺
If you’re making the claim that less Arctic ice is due to human CO2 emissions, then the onus is on you to provide testable evidence showing that Arctic ice cover is a function of human CO2 emissions.
But it’s hard to understand from your comments, so if you are saying instead that Arctic ice decline is due to factors other than CO2, then we’re on the same page.
James Abbott says: July 20, 2012 at 6:42 am
“I certainly did not “ignore” 1998 as implied.”
I know you didn’t. It is however common for many posters on WUWT ignore its effect on regression calculations.
“When we move to full El Nino, we should see new record warmth.”
Agreed.
From Steven Mosher on July 20, 2012 at 12:42 pm:
You got a link to where you got that PIPS data? Because all us non-Navy people can get is the maps. Goddard used to catch flak for pixel counting, but how else do you get the info?
In any case, 2026 doesn’t sound as bad as it could be.
Since self-flagellation until exsanguination is frowned upon in these prudish times, instead I took the PIOMAS v2.0 daily results and shoved them into a spreadsheet for analysis. Isolating the September data, placing equations just right to keep the graphs lined up… Sure got my ration of Friday fun.
All September daily numbers for all completed Septembers, linear regression, the Arctic will run out of ice before 2034 is halfway done, translate as 2033 will still have some ice in September but 2034 will run out.
But as we’re worried about when it crosses the zero line and September does have some variation, I worked with the minimums on the days they occurred. (The same minimum showed up twice on two successive days so I went with the first day.)
Effectively the same results, zero was crossed at the end of January 2034.
But then I worked with the last 10 years (2001-2011) as you mentioned.
PIOMAS v2.0 says there’ll be no remaining September Arctic sea ice in 2017.
So if the New Improved PIOMAS is correct and the linear fit is valid (R^2 by the minimums is 0.946, damn good for climate science), the ice will be gone nine years earlier than your 2026 figure.
Well since PIOMAS says there’ll be zero remaining km^3 of ice in 2017, seems it’d be a safe bet there would be be zero km^2, which is less than 10^6 km^2, of ice area three years earlier than that.
Smokey. Thats not testable. you have to define “harmless” use a measure and use a NUMBER.
Like so:
Eating an excess 4000 calories per day will result putting on 20 lbs of excess weight.
see thats testable.
but your claim is not testable, because it doesnt say anything quantifiable. “harmless” and “beneficial” need to cast as measurable entities.
Now smokey WRT ice. You are the one who claimed that ice and currents melted ice.
but during the winter there is wind and there are currents.. whats up with that? no ice melting.
Its pretty simple. ice is melted by heat. let’s see if you can agree to that.
Does c02 melt ice? nope. Does more c02 lead to a warmer planet? yes, even you agreed to that.
But, we have measurements from DMI (the DMI model as you prefer to describe it) that clearly shows that – during the melting time of the year, the only time of the year when temperatures are warmer than 0.0,C and air can melt ice) – that air temp’s have NOT exceeded 3 degrees C at any time since 1958.
Further, these same measurement prove that on a day-to-day basis – not missing any days, not skipping nor changing location nor changing measurement methods or positions – on a day-to-day basis air temperatures since 1958 are going down. The std deviation of every such air temperature is very, very little. (The winter air temperatures have wide scatter, but are irrelevant, it is only during summer that the air (and the CO2 that assumed to be warming the air) can melt ice.
But, and you are missing this significant “but” – the air temperature over central Canada (which NASA-GISS claims is going up so much with its huge rad-marked areas – isn’t over top of the ice at 50 north latitude, at 60 north latitude, and 70 north latitude. The ice is further north between 80 north latitude and 90 north. It doesn’t matter what central Canada is assumed to be doing by NASA-GISS smeared models of assumed 1200 km temperature re-calculations and homogenizations.
The actual temperature over the water (where the ice is actually located) has not changed up or down during the months of the year when it is (1) exposed to the air and (2) melting.
There is no catastrophic Arctic ice-albedo positive feedback possible; the more ice melts north of 80 north during the minimum ice coverage season (from any cause) the more heat is released from the Arctic Ocean to the air and atmosphere through evaporation and radiation.
All “Arctic”ground ice (Greenland excepted, where mountains and ice cap change things for a limited area – limited that is when compared to Arctic en total) has already melted well before the point of minimum sea ice extents in late September at the solstice. South of a rough circle around the pole at 80 north – the range of the current 4 million km@ur momisugly sea ice minimum – there is NO more ground snow and ice to melt. South of 80 north latitude, there is no more sea ice available to melt. [Actually, the sea ice minimum is slightly offset to the SW from the pole, but the “circular approximation” at 80 north latitude is within 5%.)
So, what happens if ALL of the sea ice were to vanish one September morning?
On clear days, the inbound energy from the sun would be reflected from the ocean surface – since it hits at an angle between 10 and 0 degrees (at most, even at noon) and is not absorbed on clear days, and the newly exposed water would evaporate into the air….. cooling the ocean. And each degree further north, the sun at maximum is lower down and reflects even more energy from the ocean surface. At minimum ice extents, the sun is behind the earth 12 hours a days, and the ocean faces twilight conditions from 6:00 am to 8:00 am, from 400 pm to 6:00 pm local solar time, so even the lower sun angles expose the ocean surface to inbound radiation for fewer hours.
At minimum ice extents, the myth of a 24 hour-a-day sun is wrong. Dead wrong.
The myth of a positive solar-sea-ice feedback is wrong. Dead wrong in every detail and real physical fact of geography, heat transfer, sunlight optics, atmospheric absorption of energy, and temperature.
On cloudy days, the inbound radiation, already attenuated by over 11 air masses of air, dirt, clouds, and soot and high-level ice found across the high Arctic, reflects more energy from the the top of the clouds than on clear days, and the re-reflected energy (less than 30% of the original rays) comes closer to matching the evaporation losses, but the higher winds associated with clear days increases evaporation losses. No improvement in net heat energy into the water. No heating of the air above the ocean.
There is no more land area south of the Arctic Ocean (Russia side or Canada side) to absorb any more energy from the sun than that area that is already exposed. And, what land is exposed, is growing 17 to 25% MORE vegetation and leaf matter than before 1960. Therefore, its albedo is lower, more energy is absorbed, and the LAND and air above that land heats up. More things grow, eat, die, and are food.
Since there is no more land that is exposed to the sun than the present days, there is NO Arctic amplification possible from future CO2, future solar exposure, or potential future heat increases in the Arctic south of the ocean-land boundary, nor north of the ocean beaches for that matter. All of the ice and snow that can be exposed to the sun has already melted by mid-September.
—–
In conclusion, we have shown that the air temperature above the actual areas where the sea ice is now located during the melting season have NOT increased since 1958, and that those air temperatures above and around the sea ice at 80 north are decreasing with increased CO2 concentration under sunlight exposure. At other parts of the year (times not associated with ice melt but ice growth), air temperatures at 80 north cannot be a function of re-radiated sunlight, since there is no sunlight at those times of the year.
We agree that the low air temperatures above and around the current sea ice minimum extents above 80 north latitude “should” increase the greenhouse effect of the CO2 also in the Arctic air, and therefore the Arctic air above the current sea ice extents should be increasingly warmer as more CO2 is added worldwide each year. However, that ASSUMPTION is not what is being reported by the DMI daily results over the past 50 years since 1958 – during the period of the year when the Arctic sea ice is exposed to both air and CO2 and water vapor and sunlight. We have no reason for this difference between CAGW theory and reported results of actual air temperatures where the sea ice is at minimum extents, but …. the CAGW theory just might be wrong.
We have NOT shown a reason for ice extents to be decreasing since the mid-1970’s, and will not speculate on any assumed reasons for that decline, but have shown that that a decrease in air temperature – where the sea ice actually is now (not in NASA-GISS-‘s “mid-Canada “arctic” hotspots – is consistent with lowering sea ice extents.
Further, since air temperatures are NOT increasing where the sea ice is melting during late summer – at the border between 80 north and 75 north latitudes, increased greenhouse gasses in the Arctic, at the equator, or worldwide cannot be the reason for the decline in sea ice.
We have shown increased vegetation growth due to increased OC2 is a valid reason for central Canada air temperatures to be increasing since 1960 – but those higher temperatures (if valid and not tampered with or manipulated for political and fiscal reasons) are increasing well away from the Arctic ice and therefore irrelevant with respect to Arctic ice increases or decreases at the time of sea ice minimum.
RACooke, I agree with some of what you say — it is certainly not a simple problem to figure out what is happening with the ice and what factors are involved in what ways. But I have to disagree with your statement:
There is a huge chuck of sea ice in central Canada — called Hudson Bay — that extends down to ~ 55N. It freezes every winter. The Bering Sea also freezes down to about 55 N. The Sea of Okhotsk freezes down past 50 N (or it used to 30 years ago). The east coast of Canada also freezes down to ~ 50 N. Both coasts of Greenland freeze to ~ 65N. The Arctic Ocean itself extents to about 70N, not 80N.
Thus, there are HUGE areas of ice that melt “in the south” where there is more sunlight. All spring and summer, these areas are melting. When they do, the albedo DOES change and the water DOES absorb more sunlight and the water DOES warm. This helps melt the ice further north, and slows re-freezing the next fall.
In many ways, the ice extent in June & July would matter most, since that is when the sunlight is strongest. (It surprises most people to learn that for a month or so in mid-summer, the the North Pole gets the most solar energy per day of any place on earth. In fact, any spot north of the Arctic Circle gets more energy than any spot in the tropics (at the top of the atmosphere anyway, where we ignore cloud cover, humidity, dust, etc) http://en.wikipedia.org/wiki/File:InsolationTopOfAtmosphere.png).
If you want to talk STRICTLY about 80N – 90N, then you are right that this specific area is pretty much always ice covered and pretty much doesn’t change albedo. (And furthermore, at such a glancing angle, the albedo of open ocean is pretty high anyway, so water vs ice does not make as big of a difference as many people might think.) The presence of summer ice means the air cannot ever warm above ~ 3 C. But 80N-90N is definitely not the whole story.
cookie.
air temps above melting ice will never increase… till all the ice is melted.
more concentration pictures boys… looking grim. the right change in weather… whoosh.
Area will drop below 3m sq km this year. MYI flow through fram and nares will continue to diminish volume. recovery…? not likely
http://www.iup.uni-bremen.de:8084/ssmis/arctic_SSMIS_nic.png
Tim:
Each area you mention is ice-covered in winter, melts through the spring and late spring into early summer. (The period between max ice extent at about mid-March in the northern hemisphere into the period of fastest melt in early July.)
But these areas are already melting every year.
So, if CO2 rises, there is no difference in net day-to-day earth albedo through the year “if” the Baltic, Hudson Bay or regions off of Greenland east coast melt. They ALREADY have melted this spring, next spring, and will likely continue to melt every year. The increased energy absorbed by the darker ocean water exposed to the sun’s rays is already inside the earth’s heat circulation patterns and overall heat balance.
The ONLY northern hemisphere ice that CAN melt between now and the next 10/100/1000 years is the 4 million km square little bitty “cap” that is centered around the north pole between 80 north and 90 north. Therefore, the only possible albedo change/albedo feedback change that CAN occur MUST be limited to whatever change can occur if the ice at 80 north or above melts.
Speculation about albedo changes caused by sea ice melting anywhere else on earth except the Arctic between and 80 north and 90 north, and the Antarctic ice shelves is meaningless: all other regions already have melted. What else can change in those regions to change albedo and reflected/absorbed energy?
Now, the CAGW theists need to explain WHY the air temperatures above the sea ice have decreased when the sun is actually shining during the summer months up there (Mosher started above trying to do that) despite their CO2-temperature theories; and why the Antarctic sea ice areas are generally increasing while earth’s temperatures are “claimed” to be increasing ….
But there can be NO “the sea ice is melting, the earth will heat up more” hysteria about positive feedback.
Steven Mosher said:
“Now smokey WRT ice. You are the one who claimed that ice and currents melted ice.
but during the winter there is wind and there are currents.. whats up with that? no ice melting.”
No, I said that wind and currents explain the decline in Arctic ice; you said they melted the ice.
And:
“Does c02 melt ice? nope. Does more c02 lead to a warmer planet? yes, even you agreed to that.”
Yes, I agree that CO2 causes warming: insignificant, unmeasurable warming. It is not worth worrying about.
What I worry about is how CO2 knows to melt Arctic ice — while leaving 90% of the world’s ice in the Antarctic alone. I guess CO2 has a mind of its own.☺
“But these areas are already melting every year. ”
No .. that is not true at all. They are melting MORE and melting EARLIER. This would allow more energy to be absorbed throughout the Arctic area. More energy = less ice = warmer.
“Now, the CAGW theists need to explain WHY the air temperatures above the sea ice have decreased”
Actually, you have to explain why you think this is so. I looked at the data from NOAA’s NCEP reanalysis ( http://www.esrl.noaa.gov/psd/cgi-bin/data/timeseries/timeseries.pl?ntype=1&var=Air+Temperature&level=2000&lat1=90&lat2=80&lon1=0&lon2=360&iseas=0&mon1=0&mon2=0&iarea=1&typeout=1&Submit=Create+Timeseries). This was simply a matter of convenience — NOAA numbers are easy to download in monthly format. There should not be a big difference between NOAA & DMI.
The results, quoted below, show INCREASES in the temperature for each and every month of the year. June is shows the smallest rate of increase (0.002 C/year or ~ 0.12 C increase in ~ 60 years) and June is the only month where the increases not statistically significant (p>0.05).
Can you provide your numbers and analysis that show a decreasing temperature for 80N-90N for any month?
PS. I think I see where you may have gotten your factoid. Looking a little, I see that as recently as 2010, the JUN slope was negative (although that decrease may well never have been statistically significant). If you go back to 2002 you can find negative slopes for JUL & AUG. The 1950’s were a warm decade; after a few cooler years, we are now warm (and warmer than the 1950’s).
PPS This trend is NOT seen in mid-winter. DEC, JAN, & FEB have NEVER had a statistically significant negative trend.
PS. I think I see where you may have gotten your factoid. Looking a little, I see that as recently as 2010, the JUN slope was negative (although that decrease has not been statistically significant for a decade or more, I am pretty sure). If you go back to 2002 you can find negative slopes for JUL & AUG. The 1950’s were a warm decade; after a few cooler years, we are now warm (and warmer than the 1950’s). (This trend is NOT seen in mid-winter. DEC, JAN, & FEB have NEVER had a statistically significant negative trend.)
Smokey says: “What I worry about is how CO2 knows to melt Arctic ice, while leaving 90% of the world’s ice in the Antarctic alone. I guess CO2 has a mind of its own.”
I already pointed out your faulty reasoning on this meme once in this thread.
If you want to talk about SEA ice (as you imply with your graph), the global trend is definitely DOWNWARD. SEA ice is distributed about 50-50 between the hemisphere. Each hemisphere grows in the winter and shrinks in the summer. But the north is losing sea ice faster than the south is gaining. (I will admit it is curious that the south has been gaining; it would be fascinating to dig into the causes.)
If you want to talk about TOTAL ice (as you imply with your “90%” number), TOTAL ice is concentrated in the south. GRACE gravity measurements show a decrease in Antarctic ice (and Greenland ice for that matter). So total ice is also decreasing. CO2 is NOT “leaving alone” 90% of the earth’s ice.
(Others have pointed out that GRACE might not be the last word in Antarctic ice measurements, but please stop conflating sea ice and total ice).
So now you don’t have to worry. 🙂
Tim: (and others, for that matter)
Where is that NOAA value taken? Specifically, what latitude range is it valid for? Exactly where were their thermometers positioned, and how many were used? (One can ask the same about the DMI measurements/models, but the DMI at least explicitly claims their values are for the same latitude that the southern boundary of the remaining sea ice is at.)
How was it measured, and how were the results processed?
2. The DMI values for 80 north latitude in the summer (when the sun is present to reflect from the ice, water, or ice+meltwater, and sea ice+openwater combination) that I am referring to were read directly from their website, (July 2010) for all days for the summer months for the period 1958-2010.
To repeat, regardless of temperatures anywhere else in the world, ONLY actual local air temperatures above the sea ice at 80 north – if such air temperatures are to melt the sea ice or affect the sea ice melt rate – can be used to project, predict, or back-calculate past sea ice melt rates.
Since NO sea ice is present anywhere else in the world at the current year south of 80 north latitude at the time of minimum sea ice extent, only the rough ice albedo and ocean water reflectivity of sunlight between 10 degrees and 0 at the September equinox matters in future projections of sea ice.
Actually, since the instantaneous (highest) solar elevation only happens for a few fleeting moments each day at noon, the average solar angle each hour of each day between 80 north and the pole and the average air mass between the sun and the sea ice/water surface each hour of each day between 80 north and the poleis what is important in proving that “Increased sea ice loss will continue to lower future air temperatures between 80 north latitude and the north pole.”
=====
Smooth ocean water vs rough (wave-affected) ocean water?
Argue that if you will, but provide actual measured albedo values for low light angles only!
Even Judith Curry – in all of her Arctic papers – uses a single, constant, unchanging value for open ocean water: that single value for high angles of light measured at the equator. She has at least measured the changing albedo for snow under various conditions of melt after various times of fall at various angles of incident light at various amounts of cloud cover.
======
Only a few measured values for actual “transmitted” solar energy at the Arctic surface under the solar incident angles are available (remember, even the north coast of Alaska at Point Barrow is some 10 degrees south of the southernmost sea ice extents at today’s sea ice minimum.) so available inbound solar radiation on even the clearest, most calm days of perfect visibility and perfect optical transmission must still cross 11 times more air mass above 80 north even at noon than what is crossed at the equator.
No, even future complete loss of the Arctic sea ice will NOT increase the earth’s temperature.
Sea ice loss cannot be used to prove global warming is due to increased CO2;
sea ice loss cannot be used to prove global warming is now or will be catastrophic; and continued sea ice loss will not increase the future effects of global warming.in any future scenarios, regardless of CO2 levels.
RA Cooke asks “Where is that NOAA value taken?”
Basically the same place that the DMI results come from. Both are basically “hindcasts” of conditions based on a variety of data. The NOAA numbers are for all areas north of 80N (weighted by area). I’m not saying that the results are perfect, but YOU were the one touting the temperature trends in such reanalysis numbers. You are pretty much stuck either accepting the validity of both or rejecting the validity of both.
“To repeat, regardless of temperatures anywhere else in the world, ONLY actual local air temperatures above the sea ice at 80 north – if such air temperatures are to melt the sea ice or affect the sea ice melt rate – can be used to project, predict, or back-calculate past sea ice melt rates.
No, there are three other factors (at least) that can melt the ice.
1) The ice can melt from below due to warm water. The coast of Noway stays nearly ice-free all year, due to the warm waters of the Gulf Stream. Warm water flowing into the Arctic Basin can melt the ice.
2) Ice can melt by absorbing energy from radiation rather than simply by conduction. (As an extreme example, ice will melt a lot faster in your microwave oven when you turn it on, even though the air temperature stays the same). Similarly, if you increase the incoming radiation (either solar or thermal IR) the ice will melt faster even with surface temperatures (air and ice/water) hovering right near 0 C.
3) As Smokey noted, wind and water currents matter. When the surrounding areas are choked with ice, wind and water will have less effect. The higher up the ice melts, the higher up it will be free to get carried away from the 80-90N region. While this is not specifically “melting the ice while it is within the 80-90N region” it can carry it to other warmer regions where it CAN melt.
“Even Judith Curry – in all of her Arctic papers – uses a single, constant, unchanging value for open ocean water… ”
I am not exactly sure what your point is, but I mostly agree. Albedo of water changes with angle: standard physics calculates (and experiments confirm) that light coming straight down gets almost entirely absorbed; light coming in at a glancing angle gets almost entirely reflected. Deciding on an appropriate angle to use is not as simple as finding the latitude, since waves “roughen” the surface and locally change the angle.
The net effect of waves for the equator would be to (slightly) decrease absorption; the net effect near the poles would be to (greatly) increase absorption. Overall, a single value of albedo is probably a reasonable assumption.
But that simply makes the albedo argument stronger. Ice is close to 1 for albedo. Glancing angle water is also close to 1, so the change is minimal when ice melts. But when waves change the average angle, then the water gets a lower albedo, making the change greater.
“Sea ice loss cannot be used to prove global warming is due to increased CO2;”
First of all, science never attempts to “proves” anything; science merely attempts to provide simple, coherent explanations that agree with observations.
Beyond that philosophical point, I agree that sea ice loss is not the “smoking gun” that will convince people that increased CO2 is causing warming. But disappearing sea ice is part of a fairly coherent (but not yet conclusive) explanation of the effects CO2 on IR radiation and temperature.
Since most past interglacials look to spike higher than this one, I’d predict that the next “ice free” will be during the next interglacial. About 130,000 years.
The Younger Dryas event screwed the spike of warmth in this one (giving us a cold spike and nice stable plateau instead. (Most likely a comet / space rock impact in the ice sheet of N. America that both melted the sheet AND put enough crap into the air to cause peak clipping of the warming overshoot…)
But as we are late in this interglacial time line, and things have been cooling for 6000 years (the Sahara is only green when very high temperatures over ocean water brings rains… and it was wet about 6,000 years ago. Since then we have cooled) we’re not going to have a hot spike and not going to melt the arctic. So “next time”…
“It will be interesting to see if they are biased or open and whether I get to join the “players”.
I urge WUWT readers to sign up and report your acceptances or rejections below.”
Well, I signed up and still haven’t recieved a YES or NO as of yet. It has been over 24 hours, too.
I wonder about why the Arctic has selective ice melt. Using Mosher picture above I see that most of the ice is to the West of 45W meridian line and its compliment 135East meridian. There is
relatively little ice on the other half of the arctic ? This leads me to my other questions, how much ice disappears due to sublimation versus how much due to melt ? Is there an equivalent process in the below sea surface where such activities may also happen ? Ice melt and sublimating into the ocean water ?
Politely, No – Waves do not have the influence of increasing absorbed energy from the sun at low incidence as you claim.
Under clear skies, at the latitudes under discussion, the waves are not “breaking” nor extremely high. First, you need to understand that the Arctic waves are not breaking under clear skies, they are the typical simple sine wave of period 3 to 10 meters, height 1/10 meter to 3/4 meter. At solar angles between 8 degrees above the horizon and 2 degrees above the horizon, their point of highest incident angle for the time in question at minimum ice extents, the light will impact 1/5 of the wave at higher incidence angles, 1/3 will be in complete shadow, and 1/5 at lower incidence angle. The remainder will be unchanged in incidence angle. So, 20% may absorb more energy, but 80% of the exposed surface will have either the same or decreased energy absorbed. The higher the wave, the less energy can be absorbed and the higher the evaporation rate from the increased agitation of the surface.
Look at the long term “midnight sun” photographs of the midnight sun at Point Barrow at June 22: 12 hours of reflected sunlight from the relatively calm water at low solar angles.
Photos are misleading (all self-selected for clear and calm conditions) because the photographers at 80+ north will not be “out” taking pictures under stormy conditions; but, then again, under stormy conditions, the sunlight is NOT present to be re-reflected from the surface of the exposed ocean surface either. It has already been reflected from the top of the clouds, or absorbed in the thicker clouds typical of stormy conditions. And, of course, 50% of the time at minimum ice extents there is no sunlight at all.
I tried to sign up and got a prompt acknowledgement and comment they were checking my credentials but I would hear from them soon, probably within 24 hours. So far, nothing more.