Arctic Ice

[nonentropic]

yes it is a low base but the trick with forecasting is to pick the direction changers not extrapolated steps.

a fancy Harvard professor once said "driving with the rear view mirror works great on the straights, but its the corners that get you". I think the climate world has been high jacked by a bunch of XL capable statistical people who conveniently forgot the critical calculation of errors.
I sat with a bunch of Physics lecturers arguing with each other in the 70s about whether to write calculator outputs to 8 figures, even if the error calculation said you have only 3 figures of data. unfortunately when four figure and 7 figure tables were as good as it got you sweated the errors and the significant figures now they come irrelevant and free. the illusion of accuracy.
The LIA rebound is immersed in cyclical swings and the recent lift out coincided with a rise in CO2 and there is still the possibility of a signature of the CO2 impact as well but if you think we can see that in a temperature record stretching back to just 1978 then we are deluded. Politicians are by their own admissions fueled by spin doctors not stats doctors, all parties will be unhappy about their errors when this plays out.

[cuttydyer]

Sig,

Another article on soot/black carbon:

"Gas flaring and household stoves speed Arctic thaw"



“We are seeing more and more oil being extracted further and further north. And the proximity of emissions from gas flaring matters,” says Klimont. Black carbon, or soot, contributes to warming in the Arctic by darkening the surface of snow or ice and causing it to melt faster, or absorbing more heat in the air.

The warming effect of black carbon on ice and snow has been suggested as one factor contributing to the relatively fast warming of the Arctic compared to the rest of the world. Arctic sea ice has declined faster than climate models predict, hitting new record lows in 2007 and 2012.


This map shows the surface concentrations of black carbon, from all emission sources, as simulated by the new study. The study shows that residential combustion emissions and gas flaring emissions are higher than previous studies had estimated.

Link: www.iiasa.ac.at/web/home/about/news/Oil_industry_and_household_stoves_speed_Arctic_thaw.en.html

[Andrew]

Still looks like we are in the same long term Arctic warming trend.

Other things being equal, if reasons other than extra thermal energy or heat content were causing the ice in the Arctic to decline, we would expect to see a trend of the refreeze dates becoming earlier as less ice covered the most northern parts of the Arctic.

[mondeoman]

Sept 17, 2013 6:15:45 GMT Andrew said:

Still looks like we are in the same long term Arctic warming trend.

Other things being equal, if reasons other than extra thermal energy or heat content were causing the ice in the Arctic to decline, we would expect to see a trend of the refreeze dates becoming earlier as less ice covered the most northern parts of the Arctic.

No you necessarily wouldn't see a trend in refreeze dates, but you would see an increase in the ice area/volume. The refreeze dates will be set by the position and output of the sun, within a fairly narrow window.

[Andrew]

Sept 17, 2013 8:35:35 GMT mondeoman said:

Sept 17, 2013 6:15:45 GMT Andrew said:

Still looks like we are in the same long term Arctic warming trend.

Other things being equal, if reasons other than extra thermal energy or heat content were causing the ice in the Arctic to decline, we would expect to see a trend of the refreeze dates becoming earlier as less ice covered the most northern parts of the Arctic.

No you necessarily wouldn't see a trend in refreeze dates, but you would see an increase in the ice area/volume. The refreeze dates will be set by the position and output of the sun, within a fairly narrow window.

If all of the ice was removed, you would expect an earlier rephrase date occuring in the most northern positions, than if the ice was reaching down to Southern Finland where there is still significant local heating occuring and no chance of ice remaining on the ground by day for about another two months or much more.

So, other things being equal, as the days become shorter, and there is less ice available, the colder it will be at the ice edge, and the more likely it will be to begin freezing.

[nonentropic]

Andrew i think in the extreme you are largely correct. However the difference in the insolation near the pole at the edge of the ice say this year relative to say last year is small we virtually have equinox and the energy available is trivial relative to re-radiation into black space.

the black carbon impact is something else again. clearly a strong sun will heat blackened ice very much more quickly than clean ice. will re radiation also operate more effectively, the temperature of the dark sky at night is at least 200K less than the arctic ice or water, up there the blacken surface will pour energy out into space.
intuitively you can imagine that it carbon will move turnaround dates for refreezing etc. possibly there is to much attention to this whole process because the Antarctic grows to new ice highs and really nobody has an explanation for that whilst the arctic is at a low ebb notwithstanding a lift this year.
the poles are very different but it does make the CO2 story rather flimsy and if you don't believe this note the absence of focus from the CAGW adherents.

[Andrew]

Sept 17, 2013 10:02:42 GMT nonentropic said:

Andrew i think in the extreme you are largely correct. However the difference in the insolation near the pole at the edge of the ice say this year relative to say last year is small we virtually have equinox and the energy available is trivial relative to re-radiation into black space.

the black carbon impact is something else again. clearly a strong sun will heat blackened ice very much more quickly than clean ice. will re radiation also operate more effectively, the temperature of the dark sky at night is at least 200K less than the arctic ice or water, up there the blacken surface will pour energy out into space.
intuitively you can imagine that it carbon will move turnaround dates for refreezing etc. possibly there is to much attention to this whole process because the Antarctic grows to new ice highs and really nobody has an explanation for that whilst the arctic is at a low ebb notwithstanding a lift this year.
the poles are very different but it does make the CO2 story rather flimsy and if you don't believe this note the absence of focus from the CAGW adherents.

Yes, but i am not talking about tiny changes in solar heating occuring over thousands of years. I only mentioned southern finland to illustrate my point which seems fairly obvious to me but apparently not to anybody else. However had i said Northern Norway it would have been a better example because a refreeze up there is not likely until January-February

If carbon melts the ice and there is water remaining then other things being equal you would expect water that is further north to refreeze quicker than water will do that is further south.

Yes, if carbon helps the ice to cool once the polar days are shorter it will help to refreeze the water

[cuttydyer]

Meanwhile, way down south...



nsidc.org/data/seaice_index/index.html

Paul Homewood reports: "According to NSIDC, Antarctic sea ice extent reached its all time record high on 14th September, increasing to 19.512 million sq km, and beating last year’s record high of 19.477. Records started to be kept in 1979.

This year’s record is 941,000 sq km above the long term mean, and continues an upward trend in recent years.

Extent has declined slightly in the last two days, so it may have now reached its maximum for this year."



sidads.colorado.edu/DATASETS/NOAA/G02135/south/daily/data/

UAH temperature anomalies for the lower troposphere:

vortex.nsstc.uah.edu/data/msu/t2lt/uahncdc_lt_5.6.txt

I wonder if the boys at Skeptical Science are regretting their choice of website header image:



It looks like those penguins are going to waiting a long time before palm trees start sprouting...

[zaphod]

"How fast is Arctic sea ice melting?
The Arctic's sea ice cover has reached one of its lowest ever summer minima"

www.theguardian.com/environment/2013/sep/18/how-fast-is-arctic-sea-ice-melting?guni=Network%20front:network-front%20main-4%20Pixies:Pixies:Position2

Just had to, didn't they? This is a live blog on The Guardian today. Once again, this is what goes out in the UK "quality"
press. No suggestion that there is something of a recovery, but they were probably planning a doom and gloom article anyway.
Some of the comments on the blog are interesting.

[numerouno]

Ocean warming may be a major driver of sea-ice expansion in the Antarctic, researchers report today in Nature Geoscience1. While sea ice at the North Pole has shrunk substantially over the past three decades2, scientists have struggled to explain why sea ice near the South Pole has grown in extent over the same period3.

“The paradox is that global warming leads to more cooling and more sea ice around Antarctica,” says Richard Bintanja, a climate researcher at the Royal Netherlands Meteorological Institute in Utrecht. Bintanja and his colleagues show that enhanced melting of the Antarctic ice sheet — which is losing mass at a rate of 250 gigatonnes yearly — has probably been the main factor behind the small but statistically significant sea-ice expansion in the region.

www.nature.com/ngeo/journal/v6/n5/full/ngeo1767.html

www.nature.com/news/global-warming-expands-antarctic-sea-ice-1.12709

[zaphod]

Interesting that the Guardian item I referenced doesn't even nod at the Antarctic.

Can anyone point to a reference for total planetary ice volume?

[cuttydyer]

Sept 18, 2013 15:40:01 GMT zaphod said:

Interesting that the Guardian item I referenced doesn't even nod at the Antarctic.

Can anyone point to a reference for total planetary ice volume?

Zaphod,

area, not volume but climate4you is a good resource:

www.climate4you.com/

[zaphod]

Sept 18, 2013 15:07:52 GMT numerouno said:

Ocean warming may be a major driver of sea-ice expansion in the Antarctic, researchers report today in Nature Geoscience1. While sea ice at the North Pole has shrunk substantially over the past three decades2, scientists have struggled to explain why sea ice near the South Pole has grown in extent over the same period3.

“The paradox is that global warming leads to more cooling and more sea ice around Antarctica,” says Richard Bintanja, a climate researcher at the Royal Netherlands Meteorological Institute in Utrecht. Bintanja and his colleagues show that enhanced melting of the Antarctic ice sheet — which is losing mass at a rate of 250 gigatonnes yearly — has probably been the main factor behind the small but statistically significant sea-ice expansion in the region.

www.nature.com/ngeo/journal/v6/n5/full/ngeo1767.html

www.nature.com/news/global-warming-expands-antarctic-sea-ice-1.12709

Interesting, numerouno, but the article also says:

"There are other plausible explanations for Antarctic sea-ice expansion, however. “The mechanism could be completely true, but this study does not demonstrate that increased melting has made a significant contribution to the increase in sea-ice cover,” says Paul Holland, an ocean modeller at the British Antarctic Survey in Cambridge, UK, who last year co-authored a study showing that the sea-ice expansion is caused in large part by regional wind patterns."

I am interested however in the reflective effect of increased sea ice area, which appears to me to have an effect largely independent
of volume/depth.

[zaphod]

Thanks, Cutty.

Definately worth drawing curves as well as trend lines. The planet doesn't (in my opinion) work
on straight lines but on curves.

[sigurdur]

Sept 18, 2013 15:07:52 GMT numerouno said:

Ocean warming may be a major driver of sea-ice expansion in the Antarctic, researchers report today in Nature Geoscience1. While sea ice at the North Pole has shrunk substantially over the past three decades2, scientists have struggled to explain why sea ice near the South Pole has grown in extent over the same period3.

“The paradox is that global warming leads to more cooling and more sea ice around Antarctica,” says Richard Bintanja, a climate researcher at the Royal Netherlands Meteorological Institute in Utrecht. Bintanja and his colleagues show that enhanced melting of the Antarctic ice sheet — which is losing mass at a rate of 250 gigatonnes yearly — has probably been the main factor behind the small but statistically significant sea-ice expansion in the region.

www.nature.com/ngeo/journal/v6/n5/full/ngeo1767.html

www.nature.com/news/global-warming-expands-antarctic-sea-ice-1.12709

What percent of Antarctic ice mass is 250 gigatons? Wonder if it is within error bars of mass calculations?