From the AGU weekly highlights
Composite image. Data from MODIS. Credit: National Snow and Ice Data Center.
Key Points:
- EFA method is valuable in providing quantitative assessment of feedback
- Decrease in sea ice leads to increase in cloud
- Further decline in sea ice will likely result in cloudier Arctic
Arctic sea ice has been declining over the past several decades as global climate has warmed. In fact, sea ice has declined more quickly than many models predicted, indicating that climate models may not be correctly representing some processes controlling sea ice.
One source of uncertainty in models is feedback from cloud cover. Sea ice can affect cloud cover, as melting sea ice and increased evaporation from the ocean surface can lead to more cloud formation. In the Arctic, clouds have an overall warming effect on the surface, so greater cloudiness in this region could lead to even more sea-ice melt.
Liu et al. analyzed satellite observations of cloud cover and sea ice from 2000 to 2010 to evaluate feedbacks between sea ice and cloud cover. They find that a 1 percent decrease in sea ice concentration leads to a 0.36–0.47 percent increase in cloud cover, and that 22–34 percent of variance in cloud cover can be explained by changes in sea ice. So as sea ice declines, the researchers predict that the Arctic will become cloudier.
Geophysical Research Letters, doi:10.1029/2012GL051251, 2012 A cloudier Arctic expected with diminishing sea ice
- Yinghui Liu
- Cooperative Institute for Meteorological Satellite Studies, University of Wisconsin-Madison, Madison, Wisconsin, USA;
- Jeffrey R. Key
- Center for Satellite Applications and Research, NESDIS, NOAA, Madison, Wisconsin, USA;
- Zhengyu Liu
- Department of Atmospheric and Oceanic Sciences, University of Wisconsin-Madison, Madison, Wisconsin, USA, and Center for Climate Research, University of Wisconsin-Madison, Madison, Wisconsin, USA;
- Xuanji Wang
- Cooperative Institute for Meteorological Satellite Studies, University of Wisconsin-Madison, Madison, Wisconsin, USA;
- Stephen J. Vavrus
- Center for Climate Research, University of Wisconsin-Madison, Madison, Wisconsin, USA.
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it’s all weather…but just saying that Joe Bastardi’s prediction of further snow in the Uk might turn out to be on the nose….kudos
Or maybe they are off the mark and a periodic atmospheric circulation change can explain both the sea ice decline and cloud cover change. That would strike a sensible person as perhaps a more rational approach that is internally consistent. As opposed to… trying to find a way to patch up a model by assuming that the model’s underlying assumptions remain correct.
Arctic sea ice has been increasing over the past several years as global climate has cooled. In fact, sea ice has increased more quickly than many models predicted, indicating that climate models may not be correctly representing some processes controlling sea ice.
There… Fixed it for ya.
They are just looking for patterns much the same as stock market investors do. But what patterns are they looking at as sea ice is NOT in decline?
The biggest feedback as far as global warming is concerned is supposed to be the reduced Albedo due to the reduced ice cover.
So if clouds are increasing as the ice cover declines, then that will work against the ice-Albedo feedback resulting in something closer to a wash.
And we should note that Ice Albedo feedback is responsible for the -5.0C impact of the ice ages so it is no small measure.
These guys should be fired immediately for trying to pass this garbage off as science.
A quick check of current Arctic Ice Extent shows we are a mere 2.67% below Average compared to the 30 year average on this date. a tiny 0.381 below a nearly 13.8 Million seasonal high mark.
Where exactly does the notion of the decrease ice come from, and how can it be worse than models predicted? they would have had to predict growth to make that an accurate claim.
Also, I recall many predictions of Ice Free summers, which we have not seen, and more than likely we will never see.
Do these guys have any idea how to use a calculator and NASA provided data?
Dave of Commonsense: Sea ice is cyclical. Read up at Real-Science.com. Regular voyages were made through the northwest passage around 1906, in relatively small, unprotected boats. It is generally impossible today unless using huge icebreakers with GPS and satellite video feeds showing where the leads are.
The notion that we have reduced sea ice is laughable. Compared to the peak, yes, sometimes. Compared to the trough, not even close.
BBC material world today covered Geo engineering and the scientist who advises the whole of the EU is making plans to scatter the top of the world’s atmosphere with reflective particals to make us all colder.
As ever the BBC did not once challenge that CO2 may not be as bad as the scientific concensus
(as they see it) says but seemed to think it perfectly OK to cool the Earth down by injecting man made material into the atmosphere. They failed to see the total irony of what they were approving.
http://www.bbc.co.uk/programmes/b01dvw7d
indicating that climate models may not be correctly representing some processes controlling sea ice.
=====================
…and everything after this was a waste of bits
Do these guys ever look out the window………
For those whose minds are covered by a cloudy day, . . .
How does the title “Negative Feedback” coincide with the articles content of warmer arctics? Isn’t that positive feedback? More melt leads to more clouds leads to warmth and more melt?
Or is negative used in the form of “Unwanted?”
I read
“Arctic sea ice has been declining over the past several decades as global climate has warmed.”
I go check http://nsidc.org/data/seaice_index/images/daily_images/N_timeseries.png
Can’t prove or disprove the proposition.
I go check http://www.iup.uni-bremen.de:8084/ssmis/
Remain wishing “until AMSR-2 data will become available (expected mid-2012).”
U. of Bremen had some years of history to ponder.
Michael, are you implying something not correct in my post? Perhaps you mistook my underlying sarcasm for uncertainty . The paper is crap. The Ice is not melting away.
Lately I am hearing the arguments about multiyear ice and “ice volume” which are even more laughable than claims of decreased ice extent from cloud cover.
There is not a single reliable measure of Arctic Ice Volume anywhere, period. There are some guesses, some calculations, but mostly just warmista crap.
I predict we will have ice in the Arctic this summer. 🙂
And my comment above does not even mention the lack of global warming since 1998, in any and all global databases. Not even the reversal of the warming trend since 2001, to near -0.7°C (-1.26°F) per century. That’s according to HADCRUT3 that passed away without a successor on March 11, 2012. Also, October, November and December 2011 were “warmed” in the 2011 data on that date. HADCRUT4, its succesor, has not been announced.
Superficially this looks plausible. But when you are talking about the weather in the Arctic, season cannot be overlooked. The cloud feedback in winter (with no sun at all) is going to be qualitatively very different from the cloud feedback in summer where it is daylight all the time. The article seems only able to reach its conclusions by ignoring this.
In winter clouds when clouds are likely to have a more strongly warming effect, nothing much is melting since temperature are well below freezing anyway. In the summer melt season the effect of clouds is more ambiguous and they may even have a cooling effect. Furthermore precipitation (in the form of snow on the sea) aids the formation of pack ice. And all things being equal increased cloud should lead to increased precipitation. The argument attributing melting ice to the presence of clouds only really works by ignoring all these complicating factors and presenting a simplified case. And in any case the effect is likely to be small.
The big thing that climate models completely overlook when it comes to ice levels in the arctic is the effect of changing wind patterns and ocean currents on the movement of pack ice. This is the elephant in the room. Cloud feedback effects are dubious and tiny by comparison.
Zac says:
March 29, 2012 at 6:00 pm
BBC material world today covered Geo engineering and the scientist who advises the whole of the EU is making plans to scatter the top of the world’s atmosphere with reflective particals to make us all colder….
_____________________________________
Good grief that is just what we need. A lot of Donkeys wasting tax payer money trying to bring on the next Ice Age.
Even the Warmers know we are in a dicey point near the end of the Holocene.
I wonder what will happen when a “reality feed-back” from nature wakes them up.
They find that a 1 percent decrease in sea ice concentration leads to a 0.36–0.47 percent increase in cloud cover, and that 22–34 percent of variance in cloud cover can be explained by changes in sea ice.>>>>
1. We can measure sea ice to within 1%? Not!
2. There is a definitive trend in sea ice one way or the other? Not!
3. We can measure cloud cover with tenths of a percentage? Not!
4. There is a definitive trend in cloud cover one way or the other? Not!
5. Did they present one iota of evidence or even a logical thought process showing that one was cause and the other effect? Not!
6. Did they consider that both trends (that they can’t possibly measure to that accuracy) not only may not exist, but may both be effects and that neither are a cause? Not!
Was that enough negative feedback?
Judging just by the main points:
The temperatures in the arctic during the ice melt season have been below normal these past 2 years at least.
Clouds don’t always form and stay in situ, the wind carries the clouds south where they could have less warming feedback or turn to negative feedback.
The arctic ice is known to have been low in the past, prior to the satellite era.
The low anomaly of 2007 was caused by the wind blowing ice out into southern waters.
10 years is a short time to come to any conclusions.
I should toss in to the discussion this paper
Amazing how they manage to completely disregard this type of information.
And this graph: Average Arctic temperature in melt season 80N-90N
Multidecadal variability (MDV) in the Arctic and North Atlantic climate system
adolfogiurfa says:
March 29, 2012 at 7:00 pm
I wonder what will happen when a “reality feed-back” from nature wakes them up.
________________________________________
A lot of people will move south in a hurry, only stopping to tar and feather the jokers who were predicting “global warming”.
davidmhoffer says:
March 29, 2012 at 7:05 pm
ROTFLMAO ! Well said.
Dave of Commonsense says:
March 29, 2012 at 6:46 pm
Michael, are you implying something not correct in my post? Perhaps you mistook my underlying sarcasm for uncertainty . The paper is crap. The Ice is not melting away.
No, I was agreeing with you. Steve Goddard has some great historical info on it at his site, just suggesting you go see it. The sea ice records are a joke. It’s not hard to imagine why… almost nobody lives there, only a few in history were ever able to travel through the arctic and make it out alive to tell their story, even in the best of years, but the fact that they made it at all suggests the ice had to be less than now. The guys who really measured some serious ice melt were the ones in the 1800’s, when some of the glaciers were receding at truly “unprecedented” rates. I’m sure the sea ice during those summers would have been pretty sparse compared to today’s when you’re talking about glacier recession of many miles per year back then (for decades on end). It must have been great fun for the storytellers back then too. I’m sure they had their share of bloviating doomsayers, blaming it all on evil gold prospectors or something.
The subject of the Greenland ice sheet came up today at work with the focus being the small lakes that form on the surface and sometimes disappear down a hole rather quickly. I tried but have not found information on the temperature of the water in these ponds relative to the ice temperature. If both are very close to freezing temperature then might these lakes indicate a phase change from a minor temperature change and not so much an historic influx of heat?
I guess don’t understand this post.
I agree with Ed Barbar…
“In the Arctic, clouds have an overall warming effect on the surface, so greater cloudiness in this region could lead to even more sea-ice melt.”
So…
Warmer planet leads to
Declining sea ice to lead to cloudier Arctic leads to warmer Arctic leads to
Declining sea ice to lead to cloudier Arctic leads to warmer Arctic leads to
Declining sea ice to lead to cloudier Arctic leads to warmer Arctic leads to
Declining sea ice to lead to cloudier Arctic leads to warmer Arctic leads to
That’s would seem to describe a positive feedback loop.
“They find that a 1 percent decrease in sea ice concentration leads to a 0.36–0.47 percent increase in cloud cover…”
Correlation?
Causation?