Albedo Effect At The Poles
By Paul Homewood
http://nsidc.org/data/seaice_index/index.html
We hear a lot about “melting Arctic ice” and “albedo”. For instance, NSIDC, reporting on the minimum sea ice extent in September 2013 had this to say:
The Arctic ice cap grows each winter as the sun sets for several months and shrinks each summer as the sun rises higher in the northern sky. Each year the Arctic sea ice reaches its annual minimum extent in September. It hit a new record low in 2012. This summer’s low ice extent continued the downward trend seen over the last thirty-four years. Scientists attribute this trend in large part to warming temperatures caused by climate change. Since 1979, September Arctic sea ice extent has declined by 13.7 percent per decade. Summer sea ice extent is important because, among other things, it reflects sunlight, keeping the Arctic region cool and moderating global climate.
http://nsidc.org/news/newsroom/2013_minimum_final.html
Now the more observant of you may have noticed that September does not actually fall in the summer, so the NSIDC have been rather devious here. As the albedo effect is greatest at the summer solstice, how does Arctic sea ice extent compare with the historical average at that time of year?
At 21st June this year, the extent was 10.611 million sq km, against the 1981-2010 average of 11.491, a deficit of 0.880 million sq km.
How then does this compare to Antarctic sea ice extent at the summer solstice there last year, on 21st December?
The actual extent was 11.025 million sq km, a surprisingly similar number. However, this compared to the 1981-2010 average of 9.233, giving an excess of 1.792 million sq km.
Taking the two poles together, at the summer solstice there is actually an net excess of 0.912 million sq km.
If, as they say, summer sea ice reflects sunlight, thus moderating global climate, the increase in Antarctic ice is actually having a larger cooling effect than the opposite effect in the Arctic.
We also need to factor in the facts that most of the Antarctic ice lies at lower latitudes than in the Arctic. This year, most of the deficit in the latter is in the Barents and Kara Seas, around Svalbard. This mainly lies between 75 and 80N.
In comparison, the excess ice down south is around 65S, where the albedo effect will be greater.
ftp://sidads.colorado.edu//DATASETS/NOAA/G02135/Dec/S_201412_extn.png
In terms of albedo therefore, the increasing trend of sea ice in the Antarctic is much more significant than the decline in the Arctic.
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NOT A LOT OF PEOPLE KNOW THAT 
At higher latitudes a lot of the sunlight is reflected off open water anyway, due to the shallow angle it comes in at, as this graphic shows.
Well done,
I was searching for that chart late last night, but the effects of the red wine got in the way. 🙂
The simple question to ask about the albedo effect is at perihelion vs. aphelion and progression from one to the other, and which pole is nearest the sun at each. More sea ice at perihelion means direct reflection of incoming thermal insolation, regardless of angle of incidence. Curious that NCDC climatologists don’t take albedo effects into consideration when forecasting their models.
OT, but a brilliant cartoon from Josh.
Thanks, Paul.
Sea ice is doing well in the Arctic:
From Daily AMSR2 sea ice maps: Arctic, Antarctic (University of Bremen, Germany).
At http://www.iup.uni-bremen.de:8084/amsr2/
This one shows the Arctic sea Ice somewhat more clearly,
Nearly back up to 1 deviations from the 1981-2010 mean
Yes, thanks, Andy.
Is showing it too.
Its the current slope I find quite interesting. The slope is shallower than all other recent years.
If it doesn’t steepen, there is going to be some very unhappy alarmista drones, running and ducking back under their rocks for cover.
Would be fun if we had this sort of data from most of the rest of the Holocene.
They would have to extend the vertical axis down to ZERO !
When will these bozo’s realise that the current amount of Arctic sea ice is much HIGHER than it has been for most of the last 10,000 years…
Arctic sea ice levels are anomalously HIGH, not slightly low.
… and that we are only a tiny molehill out of the coldest, nastiest period in whole of the current interglacial.
Off topic, but I wanted to get this in here:
Activist Post: Scientists Say Geo-Engineering the Sky [chemtrails] Necessary to Save Coral Reefs
“Mass bleaching is predicted over the coming decades and the scientists say geoengineering the climate might be the only way to limit the damage. The study examined the differences between a hypothetical SRM geoengineering scheme and the most aggressive CO2 reduction plan discussed by the Intergovernmental Panel on Climate Change (IPCC). The international team found that the coral reefs had a better chance of survival with geoengineering.”
http://www.activistpost.com/2015/06/scientists-say-geo-engineering-sky.html?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+ActivistPost+%28Activist+Post%29
These people are certifiable ……
….. and seriously dangerous to life on Earth !!!!
MASIE shows 2015 Arctic ice extent in a tight race with 2014.
https://rclutz.wordpress.com/2015/06/25/ice-race-neck-and-neck-plus-sipn-outlook/
First pic is not working on your site, Ron
Thanks for the comment. I am not seeing any problem with the images.
Coming up in Firefox , not in the “other” one !
Yes the melt slope is what is different this year It seems to be a much slower rate. I’m betting that this year the ice extent in the Arctic will cross the mean line (DMI) at some stage soon next 4 months say
It could happen sooner than that.
https://rclutz.files.wordpress.com/2015/06/masie-day-176.jpg?w=1140&h=372
It is tragic that all things our governments tell us have to be examined to determine if, and how, things are not what they want us to believe. Some folks have honed skills for doing this, Paul H. being one. Thanks Paul and so too to the many others.
For the NH doesn’t Greenland also contribute to albedo? This years melt in Western Greenland has been slower than in recent years.
Interesting NOAA Cfsv2 projection for the coming Arctic melt season:-
Will it happen? Anybody’s guess, just a model projection:-)
Another effect of polar albedo in upon the snowfall, which relates to replenishing of ice extent. Some interesting discussion of these dynamics here:
We find that the albedo feedback of an extended sea-ice cover in an LGM-like climate only weakly affects the reduction of snowfall rate, indicating that the insulating feedback is responsible for a large part of the suppression of precipitation by sea ice. It follows that the hydrological cycle is more sensitive to the insulating effect of sea ice than to its albedo. There are two reasons to the larger contribution of the insulating effect to the temperature-precipitation feedback. First, the overall cooling of the insulating effect is about twice than that of the albedo. This by itself is expected to lead to a more significant change in precipitation. In addition, the insulation effect not only reduce air-sea heat flux, it also directly prevents evaporation from ice-covered regions, which are a major source of precipitation over the NH ice sheets (Charles et al. 1994).
Click to access tziperman_sea.pdf
One feedback related to albedo is caused by black carbon on the ice coming mostly, these days, from Chinese power station emissions. The soot is deposited evenly throughout the ice but as the surface melts, the soot is left behind gradually making the surface darker and therefore absorbing more energy. A small change in the amount of surface melt in the early summer will lead to a greater change come September.
Yes, but airborne soot blocks sunlight as well, which would theoretically have a cooling effect. I believe that airborne soot blocking incoming sunlight was the main theory behind the Coming Ice Age scare in the 1970s.
That’s as maybe Jerry, but it’s not a feedback mechanism just a forcing agent. A cyclical change in Arctic temps would not affect the cooling effect of the airborne soot one way or another. A warming period would however have an effect on the albedo of the ice as an higher proportion of soot would be left on the surface. Conversely, if there’s a drop in Arctic temps, there’ll be less seasonal melt and the soot that has fallen that year will mostly remain buried, leaving a clean white surface.
“black carbon on the ice” – Do you think all the soot drops all on the same day so its sits like a blanket on top of the ice ?
..No I bet it falls bit by bit, day by day with each bit getting quickly covered by new layer of ice and then maybe sinks deeper in so it mostly actually ends up below the surface having little effect
Perhaps Stew you didn’t notice where I wrote, ‘ The soot is deposited evenly throughout the ice but as the surface melts, the soot is left behind gradually making the surface darker and therefore absorbing more energy.’ For example see here. As I mentioned, it’s a feedback, the more surface melt – the more soot is in the surface layer and the darker the ice becomes.
Eliza, it has happened as I guessed it would. Arctic ice extent is now higher than 2014, and poised to extend the lead.
https://rclutz.wordpress.com/2015/06/28/arctic-ice-extent-leads-2014-june-27/