Check it out. It could be an interesting discussion piece.
Helen
“Dirty snow may warm Arctic as much as greenhouse gases”
Helen is referring to Black Carbon, covered by Pielke Sr recently:
A New Paper That Highlights the First-Order Radiative Forcing Of Black Carbon Deposition
Jennifer Marohasy BSc PhD is a critical thinker with expertise in the scientific method.
Yes and yet again I remind you that the problem is ANTHROPOGENIC Global Warming not just CO2 Global Warming.
“Snow becomes dirty when soot from tailpipes, smoke stacks and forest fires enters the atmosphere and falls to the ground. Soot-infused snow is darker than natural snow. Dark surfaces absorb sunlight and cause warming, while bright surfaces reflect heat back into space and cause cooling.”
Getting complex people. Arctic is/is not melting. Greenland is/not undergoing any melting. Did previous meltings have carbon black. Did carbon black get factored in the tedious albedo row – of course not. But this paper has CO2 as well – which selective bits would we like? Has Steve McIntyre personally OK’ed it as kosher?
Once again we have a so-called scientific discussion based on assumed absolutes when the condition is only likely to produce a week or two earlier snow melt.
In all but the marginal snow pack areas, the partial melting of snow due to black carbon is met by an additional snow fall. This cycle continues through the winter and it is only in the spring when the the black carbon effect is likely to speed up the melting which is taking place anyway.
And of course, no mention was made of the fact that the black carbon had to spend some time in the atmosphere before it fell with the snow. And as there are very few forest fires, especially in the leafless deciduous forests of the northern hemisphere, in late autumn or winter then this theory must assume that the particulate matter remains in the atmosphere from mid-summer to beyond mid-winter.
The simple facts are that most black carbon from forest fires will come back to earth in the autumn rains with a smaller portion staying in the atmosphere long enough to come down in the first snow falls of winter. This will then be covered by subsequent cleaner snow falls that define the albedo signature of the snowpack for the remainder of the snow season.
I really liked the additional spin about how the black carbon will warm up the exposed soil after snow melt. Are they that desperate for content that they have to throw in the miniscule variance between the albedo of wet dirt with added trace elemental black carbon, for the week or two period before vegetation takes over.
Once again, we get initially good science mixed with ideology to produce bunkum.
“The simple facts are that most black carbon from forest fires will come back to earth in the autumn rains with a smaller portion staying in the atmosphere long enough to come down in the first snow falls of winter. This will then be covered by subsequent cleaner snow falls that define the albedo signature of the snowpack for the remainder of the snow season.”
Amazing. We can now do away with scientists, Ian has the answer for everything.
Find it difficult to believe that soot particles make any significant difference to the whiteness of snow, except in urban/industrial areas.
Maybe soot causes marginal snow to melt marginally quicker in spring in the arctic – but the warmth generated in/around cities probably melts more snow than particulate pollution.
The fact that warmer years correspond with more forest fires over the past two centuries is hardly surprising? Warm weather causes more forest fires, not vice versa.
I remember visitng the Athabasca Glacier in Canada in the 70s. The glacier had been shrinking for many years, even during the slight cooling of the 60s and 70s. Even back then, our tour guide blamed it on industrial soot changing the albedo.
The importance of this seems to be that it should be easier in principle to reduce soot emissions than CO2 emissions. Could this be a “no regrets” way to help deal with potential warming, without crippling anyone’s economy? The main target should be the soaring particulate emissions in Asia. Improve air quality in Asian cities as well; win-win rather than zero-sum.
Spot on, Bill.
SJT’s informative note reminds me that about 150 grams of warm dog turd will only melt the snow beneath it for about 10cm. And despite having a significantly altered albedo signature, there appears to be no further melting once the initial body temperature of the aforesaid turd has dissipated. One can walk past the damned thing for another month and it will continue to mock and lear at you in all it’s obscenity until it is covered by a subsequent snow fall.
Now here is a classic PhD thesis for some bright young thing to tap into the Climate megabucks.
“Reconcile the mass, albedo and snow melt characteristics of fine particulate matter with those of selected animal faeces”. Mention that one in a bar and you’re bound to get lucky, don’t you think? And given that the critical skill of a climate cretin is the capacity to talk crap, the prospects would appear to be awesome.
Says a bloke who feeds tree stumps to GCMs. No wonder there’s earthquakes.
Note that neither SJT nor Luke has had anything of substance to say on the topic.
Bill has raised a very important point which highlights the cognitive dysfunction so prevalent in Spivanthropus climatensis. The reports authors clearly identify a causal relationship between the forest fires and the black carbon on snowpack but then reverse that relationship in an attempt to validate their (modelled) theory.
The fires must have taken place first, in mid-summer, and a hotter than normal one at that, for the particulate matter to exist at all. But they then refer to, that climate cretin standard, the lagging correlation as proof.
Note also the gonzo numbers they use to extrapolate from the north polar temperature increase to the global temperature increase. They said;
“In the past two centuries, the Arctic has warmed about 1.6 degrees. Dirty snow caused .5 to 1.5 degrees of warming, or up to 94 percent of the observed change, the scientists determined”.
And they had previously stated;
“Dirty snow has had a significant impact on climate warming since the Industrial Revolution. In the past 200 years, the Earth has warmed about .8 degree Celsius. Zender, graduate student Mark Flanner, and their colleagues calculated that dirty snow caused the Earth’s temperature to rise .1 to .15 degree, or up to 19 percent of the total warming”.
Wait a minute, how can such a small area account for a fifth of the change in global mean temperature? The Earth’s surface is about 510 million km2 and the area above Lat50N, where most of the snow will be, is about 10% of that, but it includes all of the North Atlantic above Lands End and all of the Bering Sea, where there is no snow. So Arctic snow will cover about 8% of the globe for less than a third of the year.
So the maximum impact these claimed changes could produce in the global mean temperature would be only 2.5%, not 19% as claimed.
But remember, this snow is mainly present in winter when the sun is barely over the horizon. And at those sort of angles the difference in albedo caused by fine particulate matter is the proverbial three fifths of sweet FA.
At the times when Arctic solar insolation is high, the snow/ice has receded to mountain tops and the area north of Lat70N above Siberia and 75N above Alaska. This is an area less than 8 million km2 or only 1.5% of the globe.
For that area to drive a rise in global mean temperature of 0.1C would require a polar temperature increase in the order of 6.6C, and that is before adjusting for non-zenith solar angles and the impact of cloud cover.
This is another in a long line of gonzo polar climate beat ups to feed the insatiable appetites of the gullible warmers for purple science.
Why if dust or others things cause meling of snow.
WHY THEN HAVE YOU NOT FOUND THAT THE UGH VOLCANIC ERUPTIONS OF THE PAST HAVE NOT BEEN THE CAUSE OF GLOBAL WARMING SHORELY THEY WOULD HAVE BEEN WORSE THAN ANYTHING WE COULD DO. AND WHY DOES THE ICE CORES NOT SHOW IT UP.
There was in the past more soot and other nasties sent up high into the atmosphere by volcanoes than any thing man as done. That was said to have caused the ice age.
We had a fire started in the Okefenokee Swamp by lighting, has been burning for months, has spread over almost 1,000 square miles, and has produced smoke that blanketed cities hundreds of miles away. The soot will come back down, and man had nothing to do with it.
Here’s a satellite picture if anyone is interested. http://eob.gsfc.nasa.gov/Newsroom/NewImages/images.php3?img_id=17645
Here’s one from your part of the world.
http://rapidfire.sci.gsfc.nasa.gov/gallery/?2007200-0719/Australia.A2007200.0500.1km.jpg
Hey! woody’s pic links prove we have a very warm dry continent downunder
I should tease you Woody – if the fire was started by “lighting”, man did have a lot to do with it.
Yes I know what you mean !
Thank you, Luke. The mistake couldn’t have been better.
Gavin, you guys just need to plant more trees. On the other hand, kudzu might be better. This article has a picture of the plant along with a plan to transform the atmosphere of Mars so that man can live there. If it will work on Mars, it might work in Australia.
Nuts. Here’s the link to the article.
http://www.greengeek.ca/2006/07/13/terraforming-mars-%E2%80%93-part-3/
Kudzu? You have to be kidding.
This Kudzu stuff looks like just the right thing to get rid of a forest the community no longer deserves.
Mottsa remarks that he has heard little from us on this topic. Well it’s amusing to read his rant above which totally misrepresents the paper and knowledge within it. For a start the area under consideration is a fair swag of the northern hemisphere, the knowledge of carbon deposit behaviour in the field, optics of combusted aerosols, meltwater scavenging etc impressive. 17 pages of fascinating science written off by some loon at the stroke of a pen. Amazing and no wonder there are earthquakes.
As you often claim but, conspicuously, fail, once more, to substantiate. Since when has the area North of Lat.50N NOT been a “fair swag of the northern hemisphere”?
And if you had ever experienced winter in northern Europe or Canada you would immediately understand that a change in the albedo percentage is totally irrelevant when you go to work and come home IN THE DARK.
Get this through your tiny brain, Flukaldinho, winter = snow = short days = minimal sunshine. Major changes in albedo, in winter, equal jack $hit.
He hasn’t read it and he’s an idiot for still playing … zzzzzz
Looks like a fair bit of south of 50N is in as well. and of course spring and summer does arrive.
That’s why reading the paper instead of ranting helps. Was that another earthquake tremor.. ..
Ian
it will always be possible for you to rationalise away the science, but will it be sensible?
Been following the comments with interest, as I have an open mind on this one. Braddles comment seems to be the best one for the non-committed.
One question has occurrd to me. The Antarctic is shielded from most of the earth’s atmospheric movements by the circum polar winds. Are the icecap albedo’s the same for both polar regions?
Helen Mahar
Helen – seems to be detected everywhere http://www.lbl.gov/Science-Articles/Archive/sb/May-2004/04-EETD-carbonaceous-aerosols-2.html
but
http://adsabs.harvard.edu/abs/1998JGR…10311033W
The concentrations are too low to have any significant effect on snow albedo. The similarity of the Halley and south pole data suggest that ice cores should give a historical record of black carbon that is rather representative of the Antarctic as a whole and therefore indicative of trends in biomass burning throughout the southern hemisphere.
What a cop out. “Spring and summer does arrive”, indeed. Yes, and the snow melts and the black carbon becomes irrelevant.
The process of snow melt that is claimed to be warming the global mean temperature takes place on about 10% of the Earth’s surface, which accounts for about 5% of the planetary cross section, for about 10% of the year.
So at best, the global mean temperature would have a sensitivity of 0.5% to temperature rises in the Arctic, not the 19% claimed.
And this is before we get down to examining exactly how these “scientists” happened to determine what the actual black carbon readings were for all the various locations, during the relevant periods.
By the way, the Pielke link doesn’t even work.
Still haven’t realised have we. You’re a mile off. If you wish to continue to embarrass yourself raving about what you haven’t read – keep going – it’s fun to watch. But honestly don’t you think this wading in guns blazing assuming all literature is a crock is wearing a bit thin. Has it ever occurred to you that climate physicists may have hung a few numbers on these issues themselves. Space has given you the drum.
And still no substance, Luke. If I am a mile off then go right ahead and explain, to all of us, in as much detail as you need.
Go on, Luke. How could you pass up such a splendid opportunity? And stick to the core issues, none of that “bury the punter in off-topic detail”, now. Unless, of course, you are all bluff and bull$hit, again.
Nuh – sick of ya time wasting. Get your own copy or remain stoopid.