Guest Post by Willis Eschenbach
Albedo is the percentage of incident light that is reflected by an object. For years, I’ve read claims that the loss of Arctic sea ice is a positive feedback. It is logical—warming leads to less ice, less ice reduces the surface albedo; reduced surface albedo means more sunlight is absorbed; more sunlight absorbed leads to increased warming. Positive feedback. What’s not to like?
For example, in 2019 the IPCC said:
Feedbacks from the loss of summer sea ice and spring snow cover on land have contributed to amplified warming in the Arctic (high confidence).
Wim Rost pointed me to an interesting 2007 NASA article about Arctic albedo which says:
Although sea ice and snow cover had noticeably declined in the Arctic from 2000 to 2004, there had been no detectable change in the albedo measured at the top of the atmosphere: the proportion of light the Arctic reflected hadn’t changed. In other words, the ice albedo feedback that most climate models predict will ultimately amplify global warming apparently hadn’t yet kicked in.
Kato quickly understood why: not only is the Arctic’s average cloud fraction on summer days large enough—on average 0.8, or 80 percent—to mask sea ice changes, but an increase in cloudiness between 2000 and 2004 further hid any impact that sea ice and snow losses might have had on the Arctic’s ability to reflect incoming light. According to the MODIS observations, cloud fraction had increased at a rate of 0.65 percent per year between 2000 and 2004. If the trend continues, it will amount to a relative increase of about 6.5 percent per decade. At least during this short time period, says Kato, increased cloudiness in the Arctic appears to have offset the expected decline in albedo from melting sea ice and snow.
Wim suggested that I take a look to see if this process, of the changes in cloud albedo counteracting the changes in surface albedo, had continued up to the present.
Fortunately, the CERES data allows us to calculate the trends in both the surface albedo and the top-of-atmosphere (TOA) albedo. First, here’s the trend in surface albedo in percent per year, on a 1° latitude by 1° longitude basis.


Figure 1. Atlantic and Pacific centered views of the trend in surface albedo, in percent per year. Seasonal variations removed.
As expected, due to the reduction in Arctic sea ice, the albedo in the Arctic has indeed decreased significantly over the 21-year period. It’s decreased at a rate of 0.28% per year, a total of almost 6% over the 21 year period. Note also that the poles are the only part of the surface with a significant trend.
Next, here’s the top-of-atmosphere (TOA) albedo trend.


Figure 2. Atlantic and Pacific centered views of the trend in TOA albedo, in percent per year. Seasonal variations removed.
Amazing. The increase in cloud albedo has almost totally counteracted the decrease in Arctic surface albedo. The change is only six-hundredths of a percent per year, basically lost in the noise. The effect of the clouds has brought the polar regions back into line with the rest of the planet.
This inspired me to look at the correlation of the surface albedo and the cloud albedo over the period. Positive correlation of two variables means generally that when one increases, so does the other. Negative correlation means that they move in opposite directions. Figure 3 shows that result.


Figure 3. Correlation, surface albedo and cloud albedo.
This is also most interesting. It shows that the cloud albedo not only counteracts the sea ice albedo changes. It also counteracts the changes in surface albedo from snow and land ice. Not only that, but in the area of the sea ice, the correlation is around -1, meaning that surface albedo and cloud albedo move in nearly total opposition..
Examining Figure 3, it is obvious that over the land the correlation is negative almost everywhere. However, over the ocean, the correlation is clearly related to the temperature. As the Figure 4 scatterplot below shows, wherever the ocean is below about 22°C, the clouds tend to oppose any change in surface albedo.

Figure 4. Scatterplot showing the correlation of cloud and surface albedo trends versus surface temperature. Data is the gridcell-by-gridcell 21-year average values. Yellow/black line is a LOWESS smooth of the data.
Again, in the sea ice area where 21-year average temperatures are around zero, the negative correlation is almost perfect.
Discussion
With those results in mind, let me return to the 2019 IPCC claim:
Feedbacks from the loss of summer sea ice and spring snow cover on land have contributed to amplified warming in the Arctic (high confidence).
Note that despite the IPCC claim of “high confidence”, the 2007 findings of Kato and the more recent CERES data shown above demonstrate that feedback from changes in sea ice and snow cover have NOT contributed in any significant way to amplified warming in the Arctic. Cloud changes offset these sea ice and snow changes almost entirely. In short, the IPCC claim is overstated.
This highlights the problem with the claim that we should all listen to the “97% consensus” … it’s meaningless. Science is the process of overthrowing the consensus.
My best to all on a lovely fall day,
w.
PS—As usual, I ask that you quote the exact words that you are discussing. For the reasons why, see here.
Discover more from Watts Up With That?
Subscribe to get the latest posts sent to your email.
This is yet another reason why the global circulation models being unable to derive clouds from basic starting points makes them so inaccurate.
Willis You get so much out of the Ceres data that I am consumed with a wish to follow your example. Could you write a short monolog on how I an access all of theat data too, or send a couple of email links to the right place
Alastair, you should just hope that Willis doesn’t follow the same philosophy that the Climategate cabal took, viz –
“why should I show you what I’ve done – you’ll only try to find something wrong with it . . . “
Such a negative supposition is not a proper representation of Willis’s articles, code and data sourcing, repeatedly.
Willis has utilized and demonstrated access and usage of CERES data before.
Why should I share our data, you only want to test the validity or our work with which we want to redesign the entire world economy. LOL.
The whole positive feedback is worse than what Willis says. It not only assumes there is a +ve albedo feedback, it also assumes that this factor dominates the arctic climate.
They just present the naive : less ice, more heat feedback as a given and do not even ask if there are countering negative feedbacks, for example: less thermal isolation due the ice barrier; more evaporation from the now open water; more radiation to space from open water…..
This year’s sea ice minimum was 15% higher than in 2007 when AR4 and and Al Gore’s lying film started screaming about it’s imminent disappearance and “ice free summers”. ie it’s now higher than is was 15 years ago !! Hardly run away melting.
This year is fully 40% more than the OMG minimum of 2012, when the alarmists were going into overdrive. That’s a 40% increase in the last decade.
NONE of that is consistent with the idea that a positive albedo feedback is dominating arctic sea ice extent.
Alastair, I use the CERES EBAF – Level 3b data from the page here. It’s in NCDF format, which has the extension .nc, so you’ll need software able to read Net CDF files. I do all of my programming in the computer language R, which I cannot recommend enough. It is designed to handle big datasets, which is a good thing because each of the 32 different CERES datasets is 64,800 data points (1°x1° gridcells per month). There is 252 months of data, so each dataset in memory is 130.6 megabytes.
I went through and converted each of the NCDF datasets into a 3D array (latitude, longitude, time). Then I saved them in the R native format. This lets me access them without having to extract and convert them every time I need them. This gives me a folder with about 1.45 gigabytes of data.
Over the years I’ve written a host of functions to load and display the data as maps or scatterplots like those above.
I hope this helps. Let me know if you need more info.
w.
Compliments Willis on more breakthrough discoveries supporting your Emerging Thermostat hypothesis! Best David
Thank you very much Willis This should not be beyond the abilities of a superannuated geophysicist liek myself but its nice to get a bit of shortut to the source
It took me a while to figure out how netcdf files work … if you have further questions, just ask.
I use the period Mar 2000 – Feb 2021 because it’s 21 full years.
w.
How is a period from month 3 or one year to month 2 of the next year
“21 full years”?
A typo in the comment. If you look at the plots in the main post, they cover the period Mar 2000 – Feb 2021.
Willis no doubt means Feb 2021 as stated his plots in the head posting.
Fixed, thanks.
w.
Complete sets of 12 months. Not calendar years, but “the time taken by the earth to make one revolution around the sun.”
1 Mar 2000 – 28 Feb 2001 inclusive = “one year”
Hi Willis. You obviously have done some useful ground work in processing these somewhat inaccessible data formats.
A few years ago you posted your code as a matter of policy when you posted an article. Though I realise it can be extra effort cleaning up code to state where one is happy to make it public.
It would certainly be helpful to others digging into this data if you shared links to some of your code.
Thanks, Greg. There are some obstacles to my posting the code and data.
The first is the size of the data. I have it in a folder which is about a gigabyte and a half.
The next is that my code is FAR from user-friendly. It’s not even user-unfriendly. It might best be described as user-aggressive. Nothing is in order, variables get called before they get defined, it’s a hot mess. Works great, mind you … but only if you know how to work it.
Next, much of it depends on other functions that I’ve written over the years, and many of these functions depend on other functions which depend on other functions …
Finally, I’d MUCH rather do new and interesting research than spend time beating my code into usable shape …
With that said, the basic functions that I use are in a folder here. If they drive you nuts, don’t blame me … they did that to me long ago. If they depend on other functions, let me know, I’ll see what I can dig up.
w.
I agree with Willis about R programming. I have been using it for a bit over 2 years, including reading data from netCDF files and doing relatively simple graphs, usually time series plots or scatter plots of one time-series variable vs another.
Of course, it depends what results you are looking for.
Here in the UK, “The Science” that we follow, is based on an obsolete version of Excel and computer code with over 1,500 lines of undocumented spaghetti code which has been producing ludicrous, shit results for most of this Century.
But good enough, apparently for Government work.
Thanks, Professor Pantsdown Neil Ferguson! (And many others.).
As I have previously pointed out, albedo is only applicable to diffuse reflectors, notably snow, clouds, sand, suspended sediments and plankton, and to a lesser extent, vegetation. Thus, albedo is a lower-bound on total reflectivity.
https://wattsupwiththat.com/2016/09/12/why-albedo-is-the-wrong-measure-of-reflectivity-for-modeling-climate/
I’m thinking the same thing and properly really, you’d only get a valid albedo reading with the sun directly behind you
If you want to use that albedo figure to calculate absorbed solar energy you would have to do it like that.
Nice example especially for high latitudes and thus low angles of incidence woulf be the glare we’re all famialiar with that comes off wet roads, typically in the hour before sunset.
If you’re driving West and into the sun, you are are perfectly blinded by reflected sunlight.
But if you’re driving East, no problem
So how does the Sputnik compensate for that effect, if it does, otherwise all its doing is looking at the colour of the surface and assuming an albedo….
Hello hello – calls into question the measurements of Global Greening – surely Shirley, the shade of green me/you/Sputnik see will depend where the sun is relative to me/you/Sputnik.
Especially as and contrary to what you’d think, Green Things have very high albedo. Circa 0.40
As The Farmer, what really got me interested was where/when Nitrogen fertiliser had been used.
Us peasants got to be experts on Nitrogen and how green it made things:
a) Nitrogen deficient crops tended into the yellow end of the spectrum
b) High Nitrogen levels in the crop brought on a blue-ish tinge, but certainly it looked darker than the nitrogen deficient plants
What I couldn’t ‘get’ and why I got myself a solar power meter was that the darker coloured well-fed high nitrogen fields actually had a higher albedo than the poorly fed ones.
Its out there on the interweb, it will tell that fields that have been fertilised with a lot of nitrogen, esp fields growing wheat, have an albedo nudging 0.45
(Don’t tell anyone though, coz if warmists discover that the growing of wheat has an albedo raising and thus cooling effect, then mix it into the ever burgeoning crop yeilds, things really will be Worse Than We Thought)
Reportedly, increased greening in various areas has been verified by local, boots on the ground studies.What has been admitted, but, to my knowledge, rarely mentioned, is that the satellite imagery cannot differentiate types very well, as in tell the difference between trees and grass or shrubs. This seems to mean that the biomass of the increased greening is likely a wild guess.
note for Clyde, there are different measures of Albedo….in planetary heat absorption we’re talking specifically about how much of the solar spectrum is reflected, Bond Albedo, not something for interior lighting “whiteness”…
https://earthobservatory.nasa.gov/images/84499/measuring-earths-albedo
Also your 2016 reference article is “too simple”. Due to waves, eddies, plankton, foam, mist, even at steep angles of incidence, a large percentage of incident sunlight is absorbed by the ocean.
https://www2.physics.ox.ac.uk/sites/default/files/2012-03-08/2007_2_pdf_59056.pdf
Note that your linked NASA article nowhere mentions specular reflection or BRDF. Furthermore, CERES uses large bins of latitude for high-latitude reflectance measurements, angles where the reflection has the greatest change per degree of angle of incidence. Basically, the highest specular reflectance is within about 15-20 degrees of the terminator. While water is the best example of planetary specular reflectance, one can actually see the effect on the stubble and dirt clods of a harvested corn field near sunset (or sunrise).
One could write a book on all the subtleties of how specular reflectance is affected by things like the amplitude, shape, and orientation of waves. However, the important thing is that rough surfaces tend to reflect as a diffuse reflector. When the angle of incidence approaches a glancing angle, the apparent roughness declines to the point that it mimics a smooth surface. And, it is at the poles and the terminator, where the reflectance reaches 100%, that we are concerned, particularly at the poles, because that is where snow and ice are being replaced by open water. There are, of course, other minor impacts, such as meltwater pooling on ice. The point being that measuring what is called albedo only captures light that is reflected back towards the source, the sun. Specularly reflected light moves off in the opposite direction from the source and requires a detector placed opposite the position of a detector for albedo. That is why I said that albedo is a lower-bound on the total reflectivity.
My 2016 article wasn’t intended as a treatise on the behavior of light for all situations. Rather, it was intended to point out a fundamental property of reflectance that climatologists appear to be unfamiliar with, namely, Fresnel’s Equation of reflectance, which predicts specular reflectance based on the complex refractive index of a smooth reflector when light impinges at different angles. Fresnel’s Equation also tells us how much light is transmitted into water!
Note that your second citation is concerned with atmospheric correction for nadir-viewing imaging satellites, as implemented by the program 6S. It calls specular reflectance “glint.” However, because it is concerned with correcting the apparent reflectance for satellites, and sun angles that are basically low angles of incidence, it doesn’t deal with the conditions of glancing angles. That is, it ignores an important contributor to “planetary heat absorption.”
I would be delinquent if I didn’t draw your attention to the following quote in your 2nd citation:
“In the calculation of R, the current algorithm uses not the standard Fresnel equation but the method of Sidran [1981]. Sidran’s computation makes use of the complex permittivity of water, derived from refractive index. Results obtained are noticeably different from those using the standard Fresnel formula (Equation 10). The reasons for the difference are uncertain.“
In the 2016 reference, our fresnel coefficient graph is not correct. Here is what it looks like corrected for wind from another source. Y axis is .3 not 1.0, etc…
oops, here with y-axis
https://www.researchgate.net/figure/Effective-Fresnel-reflectance-coefficient-i-i14-as-function-of-viewing-nadir-angle-i_fig4_335957150
There is nothing surprising here. The Fresnel equation provides a baseline for expected reflectivity for water. Wind that produces white caps or froth introduces an additive diffuse reflectance at low angles of incidence. At high angles, the lower reflecting white caps may reduce the total reflectivity because it is inherently so high. Although, in some cases, waves may redirect light rays that will be missed by the sensor.
However, again, this treatment is in the context of what a nadir-viewing imaging satellite will record. It cuts off at 70 degrees and thus has little utility for explaining what is happening at the terminator.
Antarctic albedo is many times more important than Arctic, since southern polar sea ice reaches to lower latitudes. And Antarctic sea ice grew during the dedicated satellite era, since 1979, while Arctic extent was declining. Peak Antarctic sea ice extent was reached during the decade 2011-20, especially in 2013 and 2014. Arctic record low summer extent was by contrast in 2012.
Also, the angle of incidence of sunlight at high latitudes makes open ocean not much less reflective than white ice.
“And Antarctic sea ice grew during the dedicated satellite era”
But not significantly (0.8+/- 1.1% dec ) ….
?w=1260&ssl=1
https://nsidc.org/arcticseaicenews/charctic-interactive-sea-ice-graph/
Please compare 1979 with 2014, then try to convince anyone that the difference is insignificant.
Thanks.
But in any case, the Antarctic shows that steadily rising CO2 has no effect on sea ice extent.
Besides which of course, there has been no warming at the South Pole since contunuous records began there in the IGY of 1958.
If CO2 be well mixed, why does it cause Antarctic sea ice to grow and Arctic to fall? Every decadal average since 1979 has waxed in the southern polar region, while Arctic sea ice has waned more in each of the four decades. That trend may well reverse in this decade. The trend is up since 2012.
In Antarctica, CO2 cools.
So it appears:
Downtrend at the South Pole since 1958, with new record low:
https://wattsupwiththat.com/2021/10/03/south-pole-sees-record-cold-winter-smashing-1976-record-wapo-admits-chill-was-exceptional/
Antarctica is weird. It is very high, c. 3 km on average, and due to the low polar tropopause it is almost placed in the stratosphere. Due to very strong radiative cooling the surface is colder than the air above (temperature inversion). Adding CO2 makes the air cool faster. It is like Antarctica was part of a different planet.
To think that 52 million years ago there was no permanent ice in Antarctica outside the mountains, and there was a twilight forest several months in the dark. Only the penguins resist.
Javier: “Adding CO2 makes the air cool faster”
WR: Dense cold and dry air is nearly constantly descending over central Antarctica. More CO2 and some added H2O (by thunderstorms and hurricanes injected in the lower stratosphere) cool stratospheric air and the tropopause air.
See the UAH trends below in the spreadsheets:
Tropopause: http://vortex.nsstc.uah.edu/data/msu/v6.0/ttp/uahncdc_tp_6.0.txt
Lower Stratosphere: http://vortex.nsstc.uah.edu/data/msu/v6.0/tls/uahncdc_ls_6.0.txt
The colder the descending air flowing equatorward over the surface, the more cold oceanic upwelling around Antarctica (Ekman forces) and the cooler the Southern Hemisphere. Adding CO2 must cause a large part of the Southern Hemisphere to cool.
I wonder whether the descending air in other High-Pressure areas is also affected by colder air from above. This seems logical to me and would be another countervailing mechanism.
In winter, the stratosphere also in effect comes down to the Arctic surface, despite its being at or near sea level. Being surrounded by a cold ocean however does tend to isolate Antarctica, and its katabatic winds blast the lower elevation coastal areas.
The cooling side of the greenhouse effect?
If the GHE applied, Antarctica would be the place where it should have the biggest positive effect, rather than an apparent negative effect. The air there is so dry, that the number of CO2 and H2O molecules are closer than anywhere else.
One thing being completely ignored is the Insulating property of Ice on top of water.
Anyone with a pond knows about this, it shuts down cooling by wind induced evaporation and slows the heat loss to a much cooler atmosphere.
Not so. Altitude is relevant.
Of course it is. So is the fact that the north polar region is mostly water, while the south polar zone is mostly land.
Lol…but it’s been warming since the 😉
Assuming that the numbers have been calculated correctly, note that the uncertainty is larger than the nominal slope. What it means is that there is equal probability (68%?) that the slope is between -0.003 and 0.019 and probably is not statistically significant. That is, there is no trend.
https://breadonthewater.co.za/2021/04/05/unexpected-ice/
Thanks.
Winter maximum peaked earlier this year than usual, but Antarctic sea ice was well above normal until then.
This is much more important in the months when Arctic sea ice is low. At that point they’re is little or no sunlight in any case. It’s always been a dodgy assertion.
Add in the fact that less sea ice allows radiative cooling off the open seas, and you have a yuge negative feedback right there…
The summer solstice is in June and sea ice minimum is in September roundabout the equinox. This means for the period between equinoxes there’s a lot of sea ice anyway in fact it still increases in area/volume until May.
This has always puzzled me in claims about albedo. There is more sea ice when there is little or no sun so why is albedo of the Arctic Ocean so critical?
Sorry confused myself writing that, there is least sea ice after maximum hours of sunshine, so why is reduced albedo such a big problem. Presumably the Antarctic behaves in a similar way
Reportedly cloud albedo itself is decreasing:
https://news.agu.org/press-release/Earth-is-dimming-due-to-climate-change
This study does not mention one reported on WUWT a few years ago about an emergent temperature result measured in the southern oceans. Upon the water surface reaching a certain temperature, wee sea beasty plants were observed to release volatile organic compounds. These compounds quickly made their way into clouds, making the clouds more reflective of sunlight, lowering surface temperature. That study said the effect, if it exists in the northern hemisphere, was obscured by human air pollution.
OK, why do clouds match open sea level so well?
Perhaps the moisture and temperature are enough to form clouds if there are any nuclei to seed them? And perhaps sea salt from exposed sea surface provides exactly that?
A nice hypothesis. No more than that.
MC, for you….
Here’s a graph for the vapor pressure of water. On the Y-axis, for sea level, divide the mB by 10 and thats the % water vapor content in the air above the water (assuming 100% RH)….
So every degree warmer SST adds about 7% more water to the air above.
That air rises and some of it makes clouds as it cools. Cloud albedo about .7, ocean albedo about .1
More albedo and the Earth cools.
Less albedo and the Earth warms.
No albedo and the Earth cooks.
That’s NOT what greenhouse theory says.
Thanks for the ‘take down’, Willis. You addressed a complex issue and, through excellent graphics, made your data driven refutation of the IPCC’s ‘high confidence’ blather understandable to all.
I know you have no interest in publishing in academic journals, but surely there must be SOME academic out there who has enough curiosity to take this analysis, add whatever academic goodies are required to make it publishable, and then publish it as a way of saying, “IPCC claims…but data contradicts….”.
As you say, Willis, isn’t the very PURPOSE of science to challenge beliefs about our world with data that show those beliefs to be wrong — and then lead us to insights that are more correct (i.e., in line with how the world really works)?
Aren’t there academics out there willing to be a co-author…you provide the starting point and ideas on how to tackle the problem (like a good senior professor would do) and then the junior faculty member, desirous of tenure, takes up the challenge, does all the detailed work, and then together you publish?
While websites like this are intellectually stimulating places, they do little or nothing to impact the science we claim is broken. And, while Willis no doubt needs little help should he want to do so, isn’t there anyone here with the appropriate connections into academia who can help turn Willis’s startling discoveries into challenges to that broken science in the only way it can be “legitimately” challenged….in (gag) peer-reviewed journals?
It would be nice…but you know the “peer reviewed” journals would find excuse after excuse to reject anything that contradicts IPCC fairy tales.
This is a 1995 paper in what one might connect closer with earlier beginnings of the problem. I don’t look for papers on Impact Factors, but once in a while they appear. While the stock market is a poor analogy what is going on are hurried attributes that one might think would discourage thought.There are apparently large discipline differences in IF, this field felt left out. Concern was “turnover time” in another paper. Apparently objectivity is all numbers like models. Throw out tradition!
Meta-analysis: synthesizing research findings in ecology and evolution. Trends in Ecology & Evolution. 10(6):236-240 From the abstract–
“Unlike more traditional qualitative and narrative reviews, meta-analysis allows powerful quantitative analyses of the magnitude of effects and has a high degree of objectivity because it is based on a standardized set of statistical procedures.”
https://doi.org/10.1016/S0169-5347(00)89073-4
AGW is Not Science — AGW is Politics
In politics we take a vote. In science the one voice that disagrees with the current consensus is precisely how science advances.
The trouble an author faces to publish anything that contradicts IPCC is unbelievable. There should be one blog to publish all those horrific experiences, mentioning journals’ name, name of editor and unsubstantiated review comments.
Can you think something like that? How reviewers, editors all are working together to protect a certain agenda need to be disclosed.
Einstein didn’t join the “consensus” throng in his day, and look where that got him.
Maybe Willis should follow Albert’s example, and just keep pursuing his own scientific discoveries?
Exceptionalism tends to have a very long half-life in the stories of human discovery.
Contemporary papers in Nature, Science, etc – not so much.
“isn’t the very PURPOSE of science to challenge beliefs about our world with data that show those beliefs to be wrong”
https://wattsupwiththat.com/2021/10/01/activists-get-a-recent-paper-that-threatens-climate-alarm-narratives-removed-from-journal/
Read this easy article about why a recently published paper was removed from the journal. It doesn’t come close to supporting your speculation. Human society has rarely been different than what is revealed in the article.
Interestingly, a recent paper in Geophysical Research Letters suggests that, over the last 20 years, the retroreflecting albedo resulting from clouds has declined, as measured by Earthshine.
https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2021GL094888
Actually, the authors have only provided a first-order approximation because all terrestrial materials have a bidirectional reflectance distribution function (BRDF), which is minimal in water. However, clouds are not even a pure Lambertian reflector, and snow has a strong forward reflectance lobe (especially for low sun angles) resulting from snow flakes having a slight preferred sub-horizontal orientation, resulting in a significant, reinforcing specular reflection from the sub-aligned crystal faces. That is why walking or skiing into the sun can be dangerous and lead to ‘snow blindness’ if the eyes are not protected. The higher the angle of incidence (low sun angle) the more the reflected spectrum resembles the source. That is, the UV component is almost the same as looking directly into the sun. As far as I know, the apparent color change of specularly-reflecting materials is never accounted for in reflection and absorption calculations of surficial materials. It is first-order assumptions “all the way down.”
However, the point of this comment is really to draw attention to the claim by the researchers that cloudiness is decreasing. As usual, there appear to be claims and counter-claims about what is happening in the world.
A few years back, the vast majority of the northern hemisphere was covered in snow and ice. Yet there was no slide into colder temps due to a drastic change in albedo.
Ha! I just finished reading and digesting your excellent work Willis and then went to my news feed and what do I find?
Climate change is making Earth dimmerClimate change is making Earth dimmer (msn.com)
What a load of crap that piece is – once again, “human-caused climate change” is an assumption asserted as if it were fact. The other thing that makes me chuckle is the notion that “dimming” of the Earth is “caused by” climate change. Sounds like the cart has been placed before the horse, again.
Sounds more like a cart without a horse.
rah,
Perhaps they were referring to the dim bulbs we know as climate alarmists! They certainly do seem to be suffering from reduced wattage; maybe an intellectual brown-out!
When I saw the title of the article I assumed it was about this recent piece of climate science.
But no. ……
https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2021GL094888
Earth’s Albedo 1998–2017 as Measured From EarthshineP. R. Goode,E. Pallé,A. Shoumko,S. Shoumko,P. Montañes-Rodriguez,S. E. Koonin,
First published: 29 August 2021 https://doi.org/10.1029/2021GL094888
“The reflectance of the Earth is a fundamental climate parameter that we measured from Big Bear Solar Observatory between 1998 and 2017 by observing the earthshine using modern photometric techniques to precisely determine daily, monthly, seasonal, yearly and decadal changes in terrestrial albedo from earthshine. We find the inter-annual fluctuations in albedo to be global, while the large variations in albedo within individual nights and seasonal wanderings tend to average out over each year. We measure a gradual, but climatologically significant decline of ~ 0.5 W/m^2 in the global albedo over the two decades of data. We found no correlation between the changes in the terrestrial albedo and measures of solar activity. The inter-annual pattern of earthshine fluctuations are in good agreement with those measured by CERES (data began in 2001) even though the satellite observations are sensitive to retroflected light while earthshine is sensitive to wide-angle reflectivity. The CERES decline is about twice that of earthshine.

“Earthshine annual mean albedo anomalies 1998–2017 expressed as reflected flux in W/m^2. The error bars are shown as a shaded gray area and the dashed black line shows a linear fit to the Earthshine annual reflected energy flux anomalies. The CERES annual albedo anomalies 2001–2019, also expressed in W/m^2 are shown in blue. A linear fit to the CERES data (2001–2019) is shown with a blue dashed line. Average error bars for CERES measurements are of the order of 0.2 W/m^2.”
Did you even look at your plot, Bantam weight? The error range in their measurements is so large they don’t even know for sure if the change in albedo is positive or negative.
Their methodology is so imprecise because they’re looking at earthshine from the part of the moon unlit by the sun from a single location on Earth. They have to correct for changes in the observing site’s atmosphere, the altitude of the moon above the local horizon causing variable light extinction, the change in the topography and lunar albedo of the part of the moon’s surface that they’re looking at, their inability to see the full spectrum of the sun’s light reflected from the Earth to the moon and back to the Earth, and how the angle of the Sun to Earth to moon to Earth varies through the month and how that affects angular dependant albedo, among many, many other corrections.
I do commend you for including the plot showing errors so large that tells any thinking person that this study should not be taken too seriously.
The actual research article mentions that the uncertainty in the CERES measurements is about 0.2 W/m^2, or about 10% of the claimed decline. However, nowhere do the authors actually specify what the individual or average uncertainty is for the shaded gray area of their Earthshine measurements. Nor do they indicate whether their uncertainty represents 1 sigma or 1 sigma. It looks to me that their uncertainty is about 50% of the total claimed decline.
The above should obviously say “1 sigma or 2 sigma.” I don’t want the trolls to be confused.
First off, solar input during the Arctic summer is about 3% of direct sunlight at summer peak, such that the average is only 1.5% over the yea. Due to the low angle and solar energy absorption during travel through more atmosphere due to the low angle, insolation (solar energy input) is pathetic. It’s not much energy.
Second, open ocean areas receiving this not-so-strong solar energy input is assumed to warm due to absorbing this solar energy. Surface waters are also subject to evaporative cooling and this weak solar input (insolation) is easily canceled by this cooling. Open water is basically neutral in this system.
It is the input of warmer waters pumped from the South by the North Atlantic Oscillatio into the Arctic basin, winds blowing ice out of the Arctic to melt elsewhere in southern waters, and volcanic activity in the Arctic seafloor that melts Arctic ice. In fact, warmer seawater from the South would preferably flow along under the lower surface of Arctic ice and is much more efficient at melting the ice.
Solar energy input is a minor, at most, and probably negligible factor in Arctic ice volume and extent.
And yet, the ice melts in the Summer and grows in the Winter!
“overstated”, very tactfully put. Great post, Willis. Brief, direct and referenced, as usual. Linking this to a bunch of people who are in daily contact with members of generation z and actually making progress.
LOL! You need to read between the lines. What these data say, is that if sun light is not reflected by clouds, it gets reflected by the ice. It is true, cause both is white, and that’s how you get a correlation of -1 😉
It seems like those that compose the IPCC reports just don’t look at the data at all.
I think it’s more like they know the average politician won’t look at the data. That’s a given for the average person.
Good
The natural conclusion is thus – the phenomenon we label albedo is in every likelihood a consequence of the ‘climate’, not a causal factor.
Or – is it by sheer coincidence that the internal dynamic components of this supposed forcing are in perfect opposition?
And so perhaps, for an ‘energy balance’ temperature perspective, it would be most productive to drop albedo parameters when considering the fundamental physics of the system.
This would be quite radical, however.
Hmm, just wondering if the two albedos (frozen water versus cloud) are actually that similar as these averages make them out to be.
Clouds can be made up of water droplets or ice (or I suppose both) and so will interact with light differently. Also clouds can come and go quite quickly. Snow and sea ice tend to be more permanent.
Averaging the two for albedo might give similar averages when in fact the daily effects are drastically different. So as an example – when clouds are present they are highly effective at reflection but when they are not present additional warming gets to the Earth (water and land). But snow is effective for entire seasons or even thousands of years if you go far enough north or south.
Just me pondering your results.
Another Climate “Science” projection which is not exactly spot on.
Oh, it is surely true that absent any other factors reducing the area of white stuff lowers the albedo. Snow and ice are white stuff. With high confidence they proclaim that Captain Obvious has SPOKEN.
Albedo makes me grumpy.
Changes in albedo are almost always accompanied by changes in emissivity. You can’t just assume that energy bounces off the planet and that’s the end of the story.
commieBob October 3, 2021 12:12 pm
What makes me grumpy are uncited, unreferenced, unsupported, unlinked vague handwaving claims like this.
Changes in albedo of what? Clouds, ice, ocean, land, what?
Changes in emissivity of what? Clouds, ice, ocean, land, what?
w.
The basic physics is this:
When a photon strikes a surface it can do one of two things. It can reflect or be absorbed.
Albedo measures how likely it is for the photon to be reflected. So …
albedo + absorption = 1
For any given wavelength the coefficient of absorption equals the coefficient of emission. link
So, for any given wavelength, increasing albedo will decrease absorbed energy but will also decrease the likelihood that absorbed energy will be re-emitted. In other words, at a given wavelength, an increase in albedo will result in a decreased coefficent of emission. Given the way that most people handle albedo makes me think they have missed that simple relationship.
Of course, on Planet Earth, the downwelling radiation is mostly near visible wavelengths and the upwelling emitted radiation is mostly in the far infrared range. A material (CO2 for example) that has a low coefficient of absorption/emission at 600 nm could have a high coefficient of absorption/emission at 15 um. That gives rise to all the complications you list.
Handwaving? Not much. More like undergraduate physics. In any event, I stand by the statement that a change in albedo will almost always be accompanied by a change in the emission coefficient of the system as a whole. Maybe you could explain how it could be otherwise. You can call a friend if you need to.
Bob:
There is virtually no overlap in wavelengths between the shortwave solar radiation received by the earth and the longwave terrestrial wavelength emitted by the earth (since its temperature is so much lower).
So your point that decreasing shortwave absorption means decreasing shortwave emissivity is not important for the earth’s energy balance.
Yes and it’s nonsensical, he needs to clarify his claim
You are mixing up concepts “spectral albedo” vs “albedo”. You start with a single photon (“spectral albedo”) and then start talking about albedo and then pronouce you are using undergraduate physics … a group that would never make that stupid mistake.
Want to try and explain your concept again and perhaps using actual physics this time? Probably start with spectral albedo numbers over time and frequencies of whatever you claim is and make your point clearly. Willis has been very clear what he has done you need to do the same.
The claim is this. You cannot change albedo without also, to a greater or lesser extent, also changing the LWIR emissivity coefficient of the system as a whole.
An example would be the presence of clouds. They have quite high reflectivity for wavelengths near visible but also quite a high emissivity coefficient in the LWIR range. link
A counter example would be the presence of snow covered sea ice. Ice and snow are reasonably good insulators and reduce the energy radiated from the ocean. Also, snow has an LWIR emissivity of 0.8 vs. 0.95 for water.
So, in one case, an increase in albedo is accompanied by an increase in LWIR emissivity and in the other case the opposite happens.
Maybe someone can think of a case where changing albedo has no effect at all on LWIR emissivity. I can’t.
Some folks treat albedo like a magical mirror that reflects energy and has no other effects. That’s what makes me grumpy.
I can break your claim with ease the change is in another spectrum other than LWIR … so lets cut to the chase below.
Albedo is the sum of all the “spectral albedo” which you describe above so you have huge numbers of photons that match the frequency and power distribution of a thermal emission (look up what that looks like).
Mathematics tells you for any given albedo there are a very large number of combinations (not quite infinite because of quantization) that will give you exactly the same albedo. That fact alone defies your statement.
Now what Willis did was take that into a real system and look at the data, there is no claim that other things can’t happen he merely does an analysis of what the data shows. You can argue what the data shows but your complaint as stated is nonsense. To discuss albedo in the manner you want you need to talk about the different frequencies and changes to them you can’t talk about 1 photon.
Every photon involved in a collision with a material object has two choices. It can be absorbed or it can be reflected. Period. The probability that it does one or the other is determined by the wavelength of the photon and the physical characteristics of the material object.
Are you claiming that albedo is a magic mirror that just reflects energy, and if it changes for whatever reason there will be no other effects?
Thanks for the excellent post, Willis. You always know to get more out of the data than I expect. As always: a lot of food for thoughts!
Just one thought for now: your figure 4 shows that over oceans of 22 degrees Celsius and more the cloud albedo trend is positive: when warmer: more cloud albedo. Extra surface warming leads to more reflection of incoming solar radiation by extra clouds.
That 22 degrees Celsius is what we call ‘room temperature’. The favorite temperature for man and also a temperature favorable and/or acceptable for most of nature. That temperature is H2O controlled. What we call ‘weather’ is trying to cool above that temperature and trying to ‘keep oceans warm’ below that temperature. More stratified cloud coverage at lower temperatures coincides with more radiative cloud warming: more surface
radiation will be prevented to reach space, day and night. Clouds are very good absorbers of surface radiation and prevent surface radiative heat loss directly to space. At lower ocean temperatures than 22 degrees, clouds are more stratified: less convective movement and tending to a maximal surface coverage at lower water vapor, maximally absorbing surface radiation. Just above that 22 degrees, rising cumulus clouds already show upward convection – I checked here in Holland last summer. In humid circumstances, above 22 degrees those H2O surface cooling processes are seriously at work as shown by developing cumulus clouds. When temperatures fall below that (surface) temperature, cumulus clouds disappear and/or change in more-stratified clouds.
Seemingly this is the central temperature for H2O: 22 degrees Celsius. With clouds showing different dominating effects for surface warming/cooling above and below that temperature.
Thanks, Wim, and thanks for kicking off this train of thought. However, you say:
The y-axis in Figure 4 is not cloud albedo. It is the correlation of surface and cloud albedo.
My best to you,
w.
OK Willis, thanks for correcting.
“That 22 degrees Celsius is what we call ‘room temperature’. The favorite temperature for man”
Not for my wife (though she’s not a man). 17C is more her style.
Jeff,
Are you really bragging that your wife runs a little hot? Please cue Matty Walker in “Body Heat” before you reply!
Thank you, Mr. Röst.
I was sitting here mulling over the implications of what you just addressed and you filled in a few blanks.
And of course, thanks Mr. Eschenbach for publishing your work on this matter.
Thank you Alan Robertson. It is always interesting to know which blanks were filled in and which blanks are still open.
It is interesting to start thinking from a completely different starting point. My starting point would be an ‘All Ocean Earth’. Which weather system would it have had? What would the movements in the oceans (horizontally and vertically) have looked like? What would have set surface temperatures? At what temperature level? What about the difference in temperature gradient between the poles and the tropics? Its influence on the prevalence of winds? When less cold water could go down somewhere in the oceans (when poleward directed warm gulf streams with very saline water are lacking) and more warm water would sink in the subtropics, which deep ocean temperatures would result? What would winter polar temperatures have been when that deep water would surface at the poles?
And later: what would be the effect of putting some ‘land’ in that ‘all ocean’ world. What if all land would be unified like Pangea or nearly unified? What if all Land was centered on both poles, what if all Land was widely dispersed in small patches (islands) that would be strongly influenced by the surrounding oceans. How stable would such an Earth have been and at what temperature level?
22 Degrees Celsius is an interesting number. And H2O is an interesting molecule.
If you read the quoted IPCC comment, and I have no further context, it does not explicitly address albedo, and as for temperature I recon that surface temperature is meant. Differences in snow cover and barren soil should imply higher surface temperatures irrespective of albedo. The observations are highly interesting but the claim on feedbacks may still be valid.
Willis,
Could this be as simple as the change in water vapor transport from evaporation on the sea surface to sublimation on ice and snow leading to changes in cloud cover?
Also, have there been any trends in global albedo as CO2 levels have increased?
Always, your articles are a delight to read – light reading on a heavy subject. A big takeaway of this study concerns the nature of cloud feedback which seems to be a puzzlement to the consensus klatch. With the results of your demonstration, can anyone doubt that clouds are net negative feedback agents.
I guess my only question would be for meteorologists. Did they not have an inkling about this balancing feedback of clouds?
This post is about albedo. In scientific literature, questions have been raised about the remarkable symmetry in albedo over hemispheres. Understanding the role(s) of albedo and its symmetry is easier when understanding the processes as described by Willis.
Two principles may help to understand the symmetric albedo over hemispheres:
1. The colder hemisphere (the SH) will (by consequence of its lower temperature) show more albedo by ice shelves and snow and sea ice, and less albedo by tropical clouds. The reverse for the warmer hemisphere: more tropical clouds will form, but less polar ice and snow will be present.
2. Per hemisphere the albedo over polar areas is balanced by the cloud-sea ice mechanism described in the post: less sea ice results in more clouds over cold oceans. Tropical and subtropical oceans already tend to perform at their maximum surface temperatures: excess heat is removed from the surface by the system of tropical thunderstorms.
The whole system tries to keep ocean surface temperatures near 22 degrees. But during our present Ice House State, average ocean surface temperatures are below that 22 degrees. Even in our ‘warmer than average’ interglacial period, the average ocean temperature is year-round only 18 degrees. Actual physical processes belonging to our actual configuration of oceans and continents (and their topography) enhance surface cooling and diminish processes of ‘energy conservation’ at the surface – if compared to an ‘all ocean’ situation. When oceans would cover all of the poles and when ‘Land’ would be divided into small pieces located well dispersed over ocean surfaces, the Earth would experience a Hothouse State.
My guess: an ‘All Ocean Earth’ would have an average surface temperature somewhere around the 22 degrees Celsius. Quite different from the average of 15 degrees for our present Land/Ocean Earth.
Given a specific orbital constellation and given a specific Land/Ocean configuration each specific period has its own ‘average temperature’, whatever the forcing. The ‘H2O cooling/warming system’ sets temperatures for every orbital/geological combination. For every combination during a specific orbital setting an ‘average temperature’ is set. In case ocean temperatures rise, more tropical clouds will reflect more solar radiation, and the original balance will be restored. In case ocean temperatures would go down, more sea ice cover will prevent further cooling of polar oceans. Within each specific setting, temperatures are remarkably stable. Again: stable, whatever the forcing, because solar input over the tropics is controlled within every setting by local/regional temperatures of the oceans. And over polar areas ocean temperatures are balanced by the sea ice-cloud system, be it with decadal/centennial fluctuations.
(Only during a Glacial when fast-changing snow coverage reacts on smaller oceanic perturbances, there is a wider fluctuation in surface temperatures within the period. Lower temperatures result in more climate change. ‘Warm’ is much more stable)
The whole climate system is H2O controlled. And is modulated over longer periods by orbital situations and over still longer periods by changes in Land/Ocean configurations. This post reveals one of the more central mechanisms that stabilize temperatures around ‘the level for this period’: the polar cloud-sea ice mechanism. Well shown and described by Willis. Starring again: H2O, in the form of snow, ice, clouds, oceans, evaporation, water vapor.