Lori (21:19:02) :
Is this just normal normal or unexpectedly normal?
(PS I’m not good with graphs).
It’s within the normal ballpark.
Why it is being talked about here is because global warming predictions say Arctic ice should be in decline and this shouldn’t be happening. The ice totals are heading the opposite way predicted.

Steve Goddard (05:14:21) :
If you look at a graph of Arctic ice, you will see that the Arctic Ocean is saturated with high albedo ice through the sunny months of May-July, and the ice minimum occurs during September when the sun is setting for the winter. There is little or no absorption of solar energy in the water at that time. So loss of heat dominates. i.e. a negative feedback.
It would seem to me that this conclusion doesn’t follow. If negative feedbacks dominate as the melt season finishes, there shouldn’t be much of a delay to melt following the solstice – negative feedbacks should bring the phase change in sooner. If positive feedbacks from the summer warmth dominates (ocean albedo absorbing more heat), the warmth may be extended and ice continues melting.
Ice albedo is about 0.6. Ocean albedo is 0.06 (0 is black, 1 is white). As open water increases during melt season, the oceans absorb and store more heat.
From all I’ve read, the extended melt from solstice is a result of well-known seasonal lag in temperature shifts. This is evident from daily temp profiles, where the hottest part of the day is usually an hour or two after midday, when the sun is at its zenith.

“The seasonal lag of temperature is the amount of time between the highest incoming insolation and highest temperature on an annual basis. For instance, in the midlatitudes the highest angle that the sun makes with the surface, and thus the most intense heating, occurs around June 22nd. It isn’t until about a month later that the highest temperatures occur. The lag is often longer near a large body of water like the Great Lakes or the ocean. A temperature lag of two months is not uncommon for places located near large bodies of water.”

http://www.uwsp.edu/geO/faculty/ritter/geog101/textbook/temperature/temperature_radiation_heat_p_2.html

Surface ocean temperatures vary much slower than atmospheric temperatures due to the higher heat capacity of water (i.e. the oceans require a greater amount of energy to be heated compared with the atmosphere). As such, SSTs generally lag atmospheric temperatures on a seasonal timescale by about 3 months. The lowest SSTs are usually observed in early Spring, and the highest in early Autumn.

http://www.weatherzone.com.au/help/article.jsp?id=42

In meteorological terms, the summer solstice Solstice and winter solstice (or the maximum and minimum insolation, respectively) do not fall in the middles of summer and winter. The heights of these seasons occur up to seven weeks later because of seasonal lag

http://www.absoluteastronomy.com/topics/Season

Autocorrelations of air temperature at lags of 1–3 months are significantly greater as a result of coupling; this is especially evident at all times of the year in the southern half of the North Atlantic domain but is also
clear during summer in the model’s North Atlantic. The increased persistence on these shorter timescales is attributed to a decrease in thermal damping (Barsugli 1995).
http://www.atmos.washington.edu/~david/bhatt1998.pdf
etc
I’m not sure why you single out ocean heat loss negative feedback, nor am I sure why how this pull to cooling is reflected by an extended melt season.
I can barely remember the original point. Goal posts move so often in these blog threads!
The original point was that positive feedbacks dominate during ice ages. If open water heat loss dominates positive feedbacks, and insolation changes are a small forcing to temps, then why do ice sheets recede so drastically. Dominant negative feedbacks should stabilise the melt. If ocean heat loss is a significant negative feedback, something else must be responsible for the (relatively) rapid loss of ice. Re-glaciation is a much slower process than deglaciation. If ocean heat loss dominates other forcings during the ice sheet decrease/regrowth, the regrowth should be quicker than the recession. but it’s the other way around.
I’m not sure you have this right, Steve. On geologic time scales, positive feedbacks amplify warming. Negative feedbacks seem to dominate the cooling period (in the literature, it is owed to the slow process of GHG sinks). On seasonal time scales, ice cover change in the Arctic continues the direction it was going beyond astronomical solstice due to seasonal lag in ocean (and atmospheric) temperatures.

barry (23:30:23) :
Ice albedo is about 0.6. Ocean albedo is 0.06 (0 is black, 1 is white). As open water increases during melt season, the oceans absorb and store more heat.
Melt ice is also a good source of N and Fe which increases the lush of the spring bloom and extends into mid summer.this is an important factor in the cold water species eg Phaeocystis antarctica and Phaeocystis pouchetii (arctic) where both light and fe are limiting qualities.
This has concomitant properties in it increase sea albedo ,cloud formation and increased biomass draws down co2.
Bio optical properties in the ocean where nutrients are limited (they decrease at distance from land) produce the clearest waters on the planet.eg Morel et al, 2007
Optical properties of the clearest waters
Abstract
Optical measurements within both the visible and near ultraviolet (UV) parts of the spectrum (305–750 nm) were recently made in hyperoligotrophic waters in the South Pacific gyre (near Easter Island). The diffuse attenuation coefficients for downward irradiance, Kd(l), and the irradiance reflectances, R(l), as derived from
hyperspectral (downward and upward) irradiance measurements, exhibit very uncommon values that reflect the exceptional clarity of this huge water body. The Kd(l) values observed in the UV domain are even below the absorption coefficients found in current literature for pure water. The R(l) values (beneath the surface) exhibit a maximum as high as 13% around 390 nm. From these apparent optical properties, the absorption and backscattering coefficients can be inferred by inversion and compared to those of (optically) pure seawater. The total absorption coefficient (atot) exhibits a flat minimum (, 0.007 m21) around 410–420 nm, about twice that of pure water. At 310 nm, atot may be as low as 0.045 m21, i.e., half the value generally accepted for pure water. The particulate absorption is low compared to those of yellow substance and water and represents only ,15% of atot
in the 305–420-nm domain. The backscattering coefficient is totally dominated by that of water molecules in the UV domain. Because direct laboratory determinations of pure water absorption in the UV domain are still scarce and contradictory, we determine a tentative upper bound limit for this elusive coefficient as it results from in situ measurements.
This article is motivated by recent (2004) observations in the exceptionally clear, blueviolet waters of the anticyclonic South Pacific gyre,
This is observable in the ocean colour section of seawifs the “purple patches” are the areas of greatest absorbtion.

DeWitt Payne (18:28:21) :
“Speaking of a linear trend, Monte Carlo analysis using an AR(2) model or an AR(15) model with coefficients calculated from the Cryosphere Today data gave similar estimates for the slope: -0.04964555 Mm2/year with a standard error of 0.004429909. That means the slope is significantly different from zero. Of course, it also means that Arctic ice isn’t going to be disappearing any time soon.”
Thank you, DeWitt. Although I assume your slope estimate is: -0.04964555 Mkm2/year (i.e. Mkm2, not Mm2). It does still mean that Artcitc ice isn’t going to disappear any time soon.
Even if we extrapolate this trend into the distant future (which is questionable indeed), it obviously is going to take more than 100 years before the Arctic is “ice free” even on 1 single day in September. I guess we can already say that El Gore et. al totally lost it with their nonsensical predictions of an “ice free” Arctic by 2013.
Or maybe they simply made a misprint/misquote, and that the year should be 2130? Or maybe they have consulted Dr Mann to do their stats for them, so that the real figures have been mirror reversed, and should read 3102? Who knows, in Climate Science, anything goes.

barry (16:46:22)
“Phlogiston, the math is way over my head. Do you actually understand it yourself?
Are you implying that log-log function dynamics provide a better explanation for ice age changes than Milankovitch cycles? If Milankovitch works, what is the need to invoke highly theoretical in-system transitions.”
I dont understand the math either (as a mere biologist by training), I try to get my head around the qualitative characteristics of these systems. (I tried to convey the impression that I understood it but clearly failed!)
Concerning the Milankovitch cycles, an important class of the chaotic dynamic systems that have been studied is oscillatory systems. These are systems that are subject to periodic forcing of a regular nature, but within which complex patterns arise or emerge by the chaotic-nonlinear processes. So climate could be considered as such a system in that it is subject to periodic forcing – by the Milankovitch ortibal, precessional etc oscillations, and also solar cycles, maybe also (depending who you believe) gravitational effects of the big planets Jupiter and Saturn – aligning every 60 years.
Thus log-log type nonlinear fluctuations are not necessarily an alternative to the results of forcing. Periodically forced systems can display new, emergent periodicities in a chaotic-nonlinear response to the regular forcing stimulus. For a nice visual example of this, have a look at the video (link below) from Texas University of a vibrated container of corn-starch – it is vibrated with a regular frequency but the emergent patterns – especially the “fingers” near the end – do not have a simple relationship to the frequency of the vibration. (This video has been posted an number of times here on WUWT):

“As far as I could make out, the transitions discussed are not about amplitude changes of the whole system, but “much richer dynamics” within it.”
This is an important question – are the complex dynamics of the whole system of contained within subsystems.
A reference that I found very helpful on this subject was the PhD thesis of Matthias Bertram. It was previously on his personal web site but not anymore – however I have posted it using google-docs:
http://docs.google.com/fileview?id=0B9p_cojT-pflY2Y2MmZmMWQtOWQ0Mi00MzJkLTkyYmQtMWQ5Y2ExOTQ3ZDdm&hl=nl
This thesis includes a thorough mathematical background to the emergent pattern formation within “reaction-diffusion” systems. It is a useful document generally on non-linear pattern formation.
One classic and well-studied oscillatory reaction-diffusion system is the Belousov-Zhabotinsky reaction, which occurs under periodic forcing of light flashes. Here is Bertram’s description of it:
“The BZ reaction consists of the oxidation of malonic acid by bromate, catalyzed by metal ions in acidic aqueous solution. The reaction is known to exhibit oscillatory behavior for a wide range of control parameters when maintained in a nonequilibrium state [8, 19]. The experiments described in Ref. [40] have used a light-sensitive ruthenium-catalyzed version of the BZ reaction, where forcing can be externally applied as spatially uniform, time-periodic light pulses. The reaction proceeds in a thin porous membrane (0.4 mm thick, 22 mm in diameter) sandwiched between two continuously refreshed reservoirs of reagents. Quasi-two dimensional patterns in the spatial distribution of the ruthenium catalyst Ru(II) are imaged by measuring the light transmission through the membrane.”
My conjecture is that the earth’s climate, i.e. the system of ocean and air currents, clouds, precipitation, ice formation, mixing and temperature dynamics, that take place on the earths surface, can be likened by analogy as a reaction-diffusion system. Energy input at the equator is redistributed globally in complex patterns involving a mixture of feedbacks and interactions. It also occurs under a number of periodic forcings – earth’s rotation, day-night cycle,lunar and solar cycles, Milankotitch cycles etc..
One of the criteria for a reaction-diffusion system is an “excitable medium” in which reactions have a self-propagating nature. In chapter 3.1 on periodic forcings, the variety of complex patterns that can be obtained in the BZ reaction is illustrated (e.g. p. 26). If one is describing climate as such a system, bear in mind that chaotic- nonlinear systems operate within a multi-dimensional phase space – time is one of these dimensions. So the change (for instance) in climate patterns with time is part of the emergent pattern from such an oscillatory reaction-diffusion type system.
I came across this body of theory while trying to research an abnormal type of bone deformity in a rare genetic disease, and look at the type of perturbation of bone remodelling (resorption-formation cycle) that could account for it. I found such reaction-diffusion systems a very compelling analogy. Another system described in Bertram’s thesis is the platinum-catalysed oxidation of CO – what happens in the catalytic converter in your car exhaust. This system is very informative on the effects of negative and positive feedbacks in a chaotic-nonlinear system that I referred to earlier.
More generally, a very helpful and interesting treatment of nonlinear pattern formation in natural phenomena – written non-mathematically – is the book “Deep Simplicity” by John Gribben, Random House, NY, which I would recommend.

phlogiston, nice post. Put into high definition what I was trying to say with instinct. Your book reference “Deep Simplicity” will be added to my wish list at Amazon. If I ever get married again, I will be registered there. Much more interesting than dishes.

Anu, I would compare SST in the main Arctic currents, surface wind patterns, and AO conditions with summer melt, as well as with clear versus cloudy days, before I would make a statement as to why the ice is this or that. I think it is a combination of these factors, not dependent on any one of them.

By the way, wonderful thread. Very thoughtful posts from all.

barry (23:30:23) :
During the summer, when the sun is up high in the sky in the Arctic, there is very little open water and albedos are very high. The ice minimum occurs in September when the sun is very low above the horizon, so very little solar energy is being absorbed by the water.

Listening to the lastest blog, they’re experiencing bad weather and waiting for a re-supplies drop, if it doesn’t drop they may have to wait upto 10 days for the next drop.
After 3 weeks one of the scientists Glenn Cooper is already leaving the expedition. His work is done.
http://www.catlinarcticsurvey.com/AudioGallery.aspx

Pamela Gray (06:15:55) :
SST, AO, Arctic currents, data: they don’t want to hear that. They want this:
DISASTERS ARE COMING TO THE EARTH FROM MANMADE CO2! TAX EVERYONE TO STOP IT!
Say things along those lines then they’ll go back under the bridge and take a good nap.