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PostPosted: Sat Sep 17, 2011 6:54 pm 
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Snowy123 wrote:
And I thought that this paper brought up by Judith Curry on Climate Etc. fits this thread quite nicely.

From the conclusions...

Quote:
This article addresses probable causes of the observed reduction of the Arctic Ocean’s 179 coverage of MYI [multi-year ice] over that past decade. There is evidence of the increasingly important role 180 of atmospheric thermodynamic forcing in shaping recent changes of the Arctic MYI. In addition to direct MYI melt due to high-latitude warming, the impact of enhanced upper- ocean solar heating through numerous leads in decaying Arctic ice cover and consequent ice bottom melting has resulted in an accelerated rate of sea-ice retreat via a positive ice-albedo feedback mechanism. The pan-Arctic role of this feedback is yet to be quantified. Analysis of satellite ice motion suggests that the role of ice export through straits connecting the Arctic Ocean with sub-polar basins may be elusive. This situation probably differs from the situation that existed in the early to mid-1990s, when enhanced ice export through Fram Strait was caused by anomalous winds associated with the positive Arctic Oscillation phase. The possible long-lasting impact of anomalous winds such as those in 2004–05 or 2007 (especially when superimposed on a warming trend) on the state of MYI should not be ruled out. An intriguing feature of the scenario described here is the potential contribution of oceanic thermodynamic forcing to the recent changes of the high-latitude MYI coverage. Available observations suggest a thermodynamic coupling between the heat of the ocean interior and the sea ice. In the Canadian Basin, the impact of Pacific water warmth has been recently documented. While vertical AW [Atlantic Water] heat fluxes are negligible in the Canadian Basin, turbulent mixing may be strong enough in the western Nansen Basin to produce a sizable effect of AW heat on sea ice. In the eastern Eurasian Basin, double diffusion provides an important alternative to weak turbulent mixing for upward AW heat transport. However, this contribution to sea-ice loss remains uncertain pending new field experiments that will provide estimates of upward AW heat fluxes.

The fact that the rate of MYI recovery observed in recent years shows a delay relative to thermodynamic forcing indicates that MYI is resistant to recovery. However, the relative roles of dynamic and thermodynamic factors in recent changes of the Arctic MYI cover remains to be determined. Quantifying these roles is a high priority if we are to develop reliable forecasts of the future state of Arctic ice coverage.


The paper clearly adresses how there is more complexity to Arctic Ice melt, than what CAGW Proponents want to believe.


Where short term prediction is the goal ..... the long term climate prediction, however, is less of a problem.

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PostPosted: Sun Sep 18, 2011 8:16 am 
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Some information on the variations in measurements:

http://alignment.hep.brandeis.edu/Lab/Measurement.html

Resolution
The resolution of a measurement is how well it can distinguish between two values of the measured physical quantity. The precision of our MRT is 1.4°C. If one end of the table is 0.1°C warmer than the other, the probability of our MRT being right when it says which end is warmer will be close to 50%, because our stochastic error is much larger than the difference we are trying to observe.

When a stochastic error is gaussian, which is most of the time, there is a 68% chance that the magnitude of the error will be less than one standard deviation of the distribution. If we measure the temperature at both ends of our table, and the far end measurement is one standard deviation higher than the near end, it is 68% likely that the MRT measurement of the far end will be higher than the MRT measurement of the near end. In other words, it's 68% likely that our MRT will be correct in telling us which end is warmer, provided that the warmer end is one standard deviation warmer than the other end.

That's how we arrive at our definition of resolution. The resolution of a measurement is the amount by which the measured quantity must change for it to be 68% likely that our measurement will be correct in saying whether the change was up or down.

Because almost all stochastic errors are gaussian, the resolution of a measurement is almost always equal to its precision.

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PostPosted: Sun Sep 18, 2011 1:46 pm 
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Wayne Stollings wrote:
Some information on the variations in measurements:



I think that I would probably buy this if there were more than one high resolution datasets that were in agreement that 2011 had the record lowest Sea Ice Extent. However, this is a major outlier, and even if it is High Resolution, it should be disgarded.

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PostPosted: Sun Sep 18, 2011 1:55 pm 
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Wayne Stollings wrote:
Where short term prediction is the goal ..... the long term climate prediction, however, is less of a problem.


One of the authors in the paper points outthat unusual pulses of warm Atlantic water have been playing a major role in ice depletion in the Arctic, which can be associated with the record +AMO we saw this melt season.

Quote:
“One prominent researcher, Igor Polyakov at the University of Fairbanks, Alaska, points out that pulses of unusually warm water have been entering the Arctic Ocean from the Atlantic, which several years later are seen in the ocean north of Siberia. These pulses of water are helping to heat the upper Arctic Ocean, contributing to summer ice melt and helping to reduce winter ice growth.

Another scientist, Koji Shimada of the Japan Agency for Marine-Earth Science and Technology, reports evidence of changes in ocean circulation in the Pacific side of the Arctic Ocean. Through a complex interaction with declining sea ice, warm water entering the Arctic Ocean through Bering Strait in summer is being shunted from the Alaskan coast into the Arctic Ocean, where it fosters further ice loss. Many questions still remain to be answered, but these changes in ocean circulation may be important keys for understanding the observed loss of Arctic sea ice.”



And the record +AMO can clearly be seen in the data.

With the AMO reaching record positive states, it is unusual IMO that 2011 did not see the lowest extent recorded this melt season.

Image

Chylek et. al clearly demonstrates that there is a strong relationship with the AMO and the Arctic Temperatures.

From the abstract:

Quote:
Understanding Arctic temperature variability is essential for assessing possible future melting of the Greenland ice sheet, Arctic sea ice and Arctic permafrost. Temperature trend reversals in 1940 and 1970 separate two Arctic warming periods (1910–1940 and 1970–2008) by a significant 1940–1970 cooling period. Analyzing temperature records of the Arctic meteorological stations we find that (a) the Arctic amplification (ratio of the Arctic to global temperature trends) is not a constant but varies in time on a multi-decadal time scale, (b) the Arctic warming from 1910–1940 proceeded at a significantly faster rate than the current 1970–2008 warming, and (c) the Arctic temperature changes are highly correlated with the Atlantic Multi-decadal Oscillation (AMO) suggesting the Atlantic Ocean thermohaline circulation is linked to the Arctic temperature variability on a multi-decadal time scale.


It is the AMO that is the main temperature driver in the Arctic Basin, and plays a role in Global Temperatures as well.

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PostPosted: Sun Sep 18, 2011 2:16 pm 
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Snowy123 wrote:
Wayne Stollings wrote:
Some information on the variations in measurements:



I think that I would probably buy this if there were more than one high resolution datasets that were in agreement that 2011 had the record lowest Sea Ice Extent. However, this is a major outlier, and even if it is High Resolution, it should be disgarded.


It seems there are not more than one high resolution dataset though. If that is the criteria for having data disregarded your cloud theory and love of satellite temperature readings are to be disregarded for the same reason since there are no supporting datasets. As I said, are you sure you wish to take such a position?

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PostPosted: Sun Sep 18, 2011 2:19 pm 
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Snowy123 wrote:
Wayne Stollings wrote:
Where short term prediction is the goal ..... the long term climate prediction, however, is less of a problem.


One of the authors in the paper points outthat unusual pulses of warm Atlantic water have been playing a major role in ice depletion in the Arctic, which can be associated with the record +AMO we saw this melt season.

Quote:
“One prominent researcher, Igor Polyakov at the University of Fairbanks, Alaska, points out that pulses of unusually warm water have been entering the Arctic Ocean from the Atlantic, which several years later are seen in the ocean north of Siberia. These pulses of water are helping to heat the upper Arctic Ocean, contributing to summer ice melt and helping to reduce winter ice growth.

Another scientist, Koji Shimada of the Japan Agency for Marine-Earth Science and Technology, reports evidence of changes in ocean circulation in the Pacific side of the Arctic Ocean. Through a complex interaction with declining sea ice, warm water entering the Arctic Ocean through Bering Strait in summer is being shunted from the Alaskan coast into the Arctic Ocean, where it fosters further ice loss. Many questions still remain to be answered, but these changes in ocean circulation may be important keys for understanding the observed loss of Arctic sea ice.”



And the record +AMO can clearly be seen in the data.

With the AMO reaching record positive states, it is unusual IMO that 2011 did not see the lowest extent recorded this melt season.

Image

Chylek et. al clearly demonstrates that there is a strong relationship with the AMO and the Arctic Temperatures.

From the abstract:

Quote:
Understanding Arctic temperature variability is essential for assessing possible future melting of the Greenland ice sheet, Arctic sea ice and Arctic permafrost. Temperature trend reversals in 1940 and 1970 separate two Arctic warming periods (1910–1940 and 1970–2008) by a significant 1940–1970 cooling period. Analyzing temperature records of the Arctic meteorological stations we find that (a) the Arctic amplification (ratio of the Arctic to global temperature trends) is not a constant but varies in time on a multi-decadal time scale, (b) the Arctic warming from 1910–1940 proceeded at a significantly faster rate than the current 1970–2008 warming, and (c) the Arctic temperature changes are highly correlated with the Atlantic Multi-decadal Oscillation (AMO) suggesting the Atlantic Ocean thermohaline circulation is linked to the Arctic temperature variability on a multi-decadal time scale.


It is the AMO that is the main temperature driver in the Arctic Basin, and plays a role in Global Temperatures as well.


The confusion between weather and climate seems to be the basis for your claim of that initial paper having any relation to climate change other than the fact climate is made up of lots and lots of weather.

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PostPosted: Tue Sep 20, 2011 7:02 pm 
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Wayne Stollings wrote:
It seems there are not more than one high resolution dataset though. If that is the criteria for having data disregarded your cloud theory and love of satellite temperature readings are to be disregarded for the same reason since there are no supporting datasets. As I said, are you sure you wish to take such a position?


The comparison you try and use with high resolution ice datasets and the satellite datasets is simply wrong. With the satellite datasets for temperature, you have two satellite datsets that are usually very close to each other in terms of the readings and decadal trends. With these two datsets being in line, it is likely that the satellite data is correct to a degree.

The satellite LT data also gives a proper inspection of potential biases in the surface temperature record going back 150 years used by HadCrut, NCDC and GISS.

Klotzbach et. al 2009 confirms that in comparison with the satellite data, the Surface has been warming faster than the LT, which could be attributed to poor citing in weather stations.

From the conclusions:

Quote:
We find that there have, in general, been larger linear
trends in surface temperature data sets such as the NCDC
and HadCRUTv3 surface data sets when compared with the
UAH and RSS lower-tropospheric data sets, especially over
land areas.

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PostPosted: Tue Sep 20, 2011 7:04 pm 
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Wayne Stollings wrote:
The confusion between weather and climate seems to be the basis for your claim of that initial paper having any relation to climate change other than the fact climate is made up of lots and lots of weather.


The AMO is not weather. It is a multidecadal cyclical oscillation that fluctuates between positive and negative states over 20-30 years. Weather does not happen over 20 to 30 years. Climate does.

The two papers attribute the loss in Arctic Sea Ice over the last 30 years to the +AMO.

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PostPosted: Tue Sep 20, 2011 8:33 pm 
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Snowy123 wrote:
Wayne Stollings wrote:
It seems there are not more than one high resolution dataset though. If that is the criteria for having data disregarded your cloud theory and love of satellite temperature readings are to be disregarded for the same reason since there are no supporting datasets. As I said, are you sure you wish to take such a position?


The comparison you try and use with high resolution ice datasets and the satellite datasets is simply wrong. With the satellite datasets for temperature, you have two satellite datsets that are usually very close to each other in terms of the readings and decadal trends. With these two datsets being in line, it is likely that the satellite data is correct to a degree.


To no more degree than the surface temperature datasets, which are also similar. Thus, you cannot claim one is any better than the rest because the variation between the satellite sets is too close to the variation between the satellite and non-satellite sets.

Quote:
The satellite LT data also gives a proper inspection of potential biases in the surface temperature record going back 150 years used by HadCrut, NCDC and GISS.


Not really as you have to assume which is biased and which is not and that is where your problem begins.

Quote:
Klotzbach et. al 2009 confirms that in comparison with the satellite data, the Surface has been warming faster than the LT, which could be attributed to poor citing in weather stations.

From the conclusions:

Quote:
We find that there have, in general, been larger linear
trends in surface temperature data sets such as the NCDC
and HadCRUTv3 surface data sets when compared with the
UAH and RSS lower-tropospheric data sets, especially over
land areas.


Yes there have been slightly larger trends, but that does not prove any of the sets are more accurate than the others since the total temperature is still very similar between them all.

Please note there is no confirmation of your assumptiom of the bias being in any particular set.

We conclude that the fact that trends in thermometerestimated
surface warming over land areas have been larger
than trends in the lower troposphere estimated from satellites
and radiosondes is most parsimoniously explained by
the first possible explanation offered by Santer et al. [2005].
Specifically, the characteristics of the divergence across the
data sets are strongly suggestive that it is an artifact resulting
from the data quality of the surface, satellite and/or radiosonde
observations
. These findings indicate that the reconciliation
of differences between surface and satellite data sets
[Karl et al., 2006] has not yet occurred, and we have offered a
suggested reason for the continuing lack of reconciliation.


Note the "and/or" indicates the problem could be with all of the sets or just one, including the satellite sets.

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PostPosted: Tue Sep 20, 2011 8:37 pm 
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Snowy123 wrote:
Wayne Stollings wrote:
The confusion between weather and climate seems to be the basis for your claim of that initial paper having any relation to climate change other than the fact climate is made up of lots and lots of weather.


The AMO is not weather. It is a multidecadal cyclical oscillation that fluctuates between positive and negative states over 20-30 years. Weather does not happen over 20 to 30 years. Climate does.

The two papers attribute the loss in Arctic Sea Ice over the last 30 years to the +AMO.


The initial paper, (you know the one I referenced?) does not as it clearly dealt with a single decade.

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PostPosted: Wed Sep 21, 2011 6:16 pm 
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Wayne Stollings wrote:
The initial paper, (you know the one I referenced?) does not as it clearly dealt with a single decade.


To my knowledge you have not referenced a single paper that deals with the AMO on this thread.

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PostPosted: Wed Sep 21, 2011 8:06 pm 
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Snowy123 wrote:
Wayne Stollings wrote:
The initial paper, (you know the one I referenced?) does not as it clearly dealt with a single decade.


To my knowledge you have not referenced a single paper that deals with the AMO on this thread.


So the reference to the AMO in response to my pointing out the confusion between weather and climate in that initial paper was just a deflection?

Wayne Stollings wrote:
Snowy123 wrote:
Wayne Stollings wrote:
Where short term prediction is the goal ..... the long term climate prediction, however, is less of a problem.


One of the authors in the paper points outthat unusual pulses of warm Atlantic water have been playing a major role in ice depletion in the Arctic, which can be associated with the record +AMO we saw this melt season.

Quote:
“One prominent researcher, Igor Polyakov at the University of Fairbanks, Alaska, points out that pulses of unusually warm water have been entering the Arctic Ocean from the Atlantic, which several years later are seen in the ocean north of Siberia. These pulses of water are helping to heat the upper Arctic Ocean, contributing to summer ice melt and helping to reduce winter ice growth.

Another scientist, Koji Shimada of the Japan Agency for Marine-Earth Science and Technology, reports evidence of changes in ocean circulation in the Pacific side of the Arctic Ocean. Through a complex interaction with declining sea ice, warm water entering the Arctic Ocean through Bering Strait in summer is being shunted from the Alaskan coast into the Arctic Ocean, where it fosters further ice loss. Many questions still remain to be answered, but these changes in ocean circulation may be important keys for understanding the observed loss of Arctic sea ice.”



And the record +AMO can clearly be seen in the data.

With the AMO reaching record positive states, it is unusual IMO that 2011 did not see the lowest extent recorded this melt season.

Image

Chylek et. al clearly demonstrates that there is a strong relationship with the AMO and the Arctic Temperatures.

From the abstract:

Quote:
Understanding Arctic temperature variability is essential for assessing possible future melting of the Greenland ice sheet, Arctic sea ice and Arctic permafrost. Temperature trend reversals in 1940 and 1970 separate two Arctic warming periods (1910–1940 and 1970–2008) by a significant 1940–1970 cooling period. Analyzing temperature records of the Arctic meteorological stations we find that (a) the Arctic amplification (ratio of the Arctic to global temperature trends) is not a constant but varies in time on a multi-decadal time scale, (b) the Arctic warming from 1910–1940 proceeded at a significantly faster rate than the current 1970–2008 warming, and (c) the Arctic temperature changes are highly correlated with the Atlantic Multi-decadal Oscillation (AMO) suggesting the Atlantic Ocean thermohaline circulation is linked to the Arctic temperature variability on a multi-decadal time scale.


It is the AMO that is the main temperature driver in the Arctic Basin, and plays a role in Global Temperatures as well.


The confusion between weather and climate seems to be the basis for your claim of that initial paper having any relation to climate change other than the fact climate is made up of lots and lots of weather.


This would be the initial paper referenced, since it seems to be lost in the discussion now.

Snowy123 wrote:
And I thought that this paper brought up by Judith Curry on Climate Etc. fits this thread quite nicely.

From the conclusions...

Quote:
This article addresses probable causes of the observed reduction of the Arctic Ocean’s 179 coverage of MYI [multi-year ice] over that past decade. There is evidence of the increasingly important role 180 of atmospheric thermodynamic forcing in shaping recent changes of the Arctic MYI. In addition to direct MYI melt due to high-latitude warming, the impact of enhanced upper- ocean solar heating through numerous leads in decaying Arctic ice cover and consequent ice bottom melting has resulted in an accelerated rate of sea-ice retreat via a positive ice-albedo feedback mechanism. The pan-Arctic role of this feedback is yet to be quantified. Analysis of satellite ice motion suggests that the role of ice export through straits connecting the Arctic Ocean with sub-polar basins may be elusive. This situation probably differs from the situation that existed in the early to mid-1990s, when enhanced ice export through Fram Strait was caused by anomalous winds associated with the positive Arctic Oscillation phase. The possible long-lasting impact of anomalous winds such as those in 2004–05 or 2007 (especially when superimposed on a warming trend) on the state of MYI should not be ruled out. An intriguing feature of the scenario described here is the potential contribution of oceanic thermodynamic forcing to the recent changes of the high-latitude MYI coverage. Available observations suggest a thermodynamic coupling between the heat of the ocean interior and the sea ice. In the Canadian Basin, the impact of Pacific water warmth has been recently documented. While vertical AW [Atlantic Water] heat fluxes are negligible in the Canadian Basin, turbulent mixing may be strong enough in the western Nansen Basin to produce a sizable effect of AW heat on sea ice. In the eastern Eurasian Basin, double diffusion provides an important alternative to weak turbulent mixing for upward AW heat transport. However, this contribution to sea-ice loss remains uncertain pending new field experiments that will provide estimates of upward AW heat fluxes.

The fact that the rate of MYI recovery observed in recent years shows a delay relative to thermodynamic forcing indicates that MYI is resistant to recovery. However, the relative roles of dynamic and thermodynamic factors in recent changes of the Arctic MYI cover remains to be determined. Quantifying these roles is a high priority if we are to develop reliable forecasts of the future state of Arctic ice coverage.


The paper clearly adresses how there is more complexity to Arctic Ice melt, than what CAGW Proponents want to believe.

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PostPosted: Sat Sep 24, 2011 7:51 am 
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Wayne Stollings wrote:
So the reference to the AMO in response to my pointing out the confusion between weather and climate in that initial paper was just a deflection?



No, you said "the paper I referenced, not the paper "you" referenced.

From the paper:

Quote:
This situation probably differs from the situation that existed in the early to mid-1990s, when enhanced ice export through Fram Strait was caused by anomalous winds associated with the positive Arctic Oscillation phase.


They refer to the situation being different from the Mid 1990s, because this is when the AMO turned positive.

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PostPosted: Sat Sep 24, 2011 10:14 am 
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Snowy123 wrote:
Wayne Stollings wrote:
So the reference to the AMO in response to my pointing out the confusion between weather and climate in that initial paper was just a deflection?



No, you said "the paper I referenced, not the paper "you" referenced.


Yes the paper you (Snowy) referenced dealing with short term prediction:

Snowy123 wrote:
Wayne Stollings wrote:
The initial paper, (you know the one I referenced?) does not as it clearly dealt with a single decade.


To my knowledge you have not referenced a single paper that deals with the AMO on this thread.




Snowy123 wrote:
And I thought that this paper brought up by Judith Curry on Climate Etc. fits this thread quite nicely.

From the conclusions... (with the decade reference highlighted)

Quote:
This article addresses probable causes of the observed reduction of the Arctic Ocean’s 179 coverage of MYI [multi-year ice] over that past decade. There is evidence of the increasingly important role 180 of atmospheric thermodynamic forcing in shaping recent changes of the Arctic MYI. In addition to direct MYI melt due to high-latitude warming, the impact of enhanced upper- ocean solar heating through numerous leads in decaying Arctic ice cover and consequent ice bottom melting has resulted in an accelerated rate of sea-ice retreat via a positive ice-albedo feedback mechanism. The pan-Arctic role of this feedback is yet to be quantified. Analysis of satellite ice motion suggests that the role of ice export through straits connecting the Arctic Ocean with sub-polar basins may be elusive. This situation probably differs from the situation that existed in the early to mid-1990s, when enhanced ice export through Fram Strait was caused by anomalous winds associated with the positive Arctic Oscillation phase. The possible long-lasting impact of anomalous winds such as those in 2004–05 or 2007 (especially when superimposed on a warming trend) on the state of MYI should not be ruled out. An intriguing feature of the scenario described here is the potential contribution of oceanic thermodynamic forcing to the recent changes of the high-latitude MYI coverage. Available observations suggest a thermodynamic coupling between the heat of the ocean interior and the sea ice. In the Canadian Basin, the impact of Pacific water warmth has been recently documented. While vertical AW [Atlantic Water] heat fluxes are negligible in the Canadian Basin, turbulent mixing may be strong enough in the western Nansen Basin to produce a sizable effect of AW heat on sea ice. In the eastern Eurasian Basin, double diffusion provides an important alternative to weak turbulent mixing for upward AW heat transport. However, this contribution to sea-ice loss remains uncertain pending new field experiments that will provide estimates of upward AW heat fluxes.

The fact that the rate of MYI recovery observed in recent years shows a delay relative to thermodynamic forcing indicates that MYI is resistant to recovery. However, the relative roles of dynamic and thermodynamic factors in recent changes of the Arctic MYI cover remains to be determined. Quantifying these roles is a high priority if we are to develop reliable forecasts of the future state of Arctic ice coverage.


The paper clearly adresses how there is more complexity to Arctic Ice melt, than what CAGW Proponents want to believe.


Not the papers mentioned in your reply:


Snowy123 wrote:
Wayne Stollings wrote:
Where short term prediction is the goal ..... the long term climate prediction, however, is less of a problem.


One of the authors in the paper points outthat unusual pulses of warm Atlantic water have been playing a major role in ice depletion in the Arctic, which can be associated with the record +AMO we saw this melt season.

Quote:
“One prominent researcher, Igor Polyakov at the University of Fairbanks, Alaska, points out that pulses of unusually warm water have been entering the Arctic Ocean from the Atlantic, which several years later are seen in the ocean north of Siberia. These pulses of water are helping to heat the upper Arctic Ocean, contributing to summer ice melt and helping to reduce winter ice growth.

Another scientist, Koji Shimada of the Japan Agency for Marine-Earth Science and Technology, reports evidence of changes in ocean circulation in the Pacific side of the Arctic Ocean. Through a complex interaction with declining sea ice, warm water entering the Arctic Ocean through Bering Strait in summer is being shunted from the Alaskan coast into the Arctic Ocean, where it fosters further ice loss. Many questions still remain to be answered, but these changes in ocean circulation may be important keys for understanding the observed loss of Arctic sea ice.”



And the record +AMO can clearly be seen in the data.

With the AMO reaching record positive states, it is unusual IMO that 2011 did not see the lowest extent recorded this melt season.

Image

Chylek et. al clearly demonstrates that there is a strong relationship with the AMO and the Arctic Temperatures.

From the abstract:

Quote:
Understanding Arctic temperature variability is essential for assessing possible future melting of the Greenland ice sheet, Arctic sea ice and Arctic permafrost. Temperature trend reversals in 1940 and 1970 separate two Arctic warming periods (1910–1940 and 1970–2008) by a significant 1940–1970 cooling period. Analyzing temperature records of the Arctic meteorological stations we find that (a) the Arctic amplification (ratio of the Arctic to global temperature trends) is not a constant but varies in time on a multi-decadal time scale, (b) the Arctic warming from 1910–1940 proceeded at a significantly faster rate than the current 1970–2008 warming, and (c) the Arctic temperature changes are highly correlated with the Atlantic Multi-decadal Oscillation (AMO) suggesting the Atlantic Ocean thermohaline circulation is linked to the Arctic temperature variability on a multi-decadal time scale.


It is the AMO that is the main temperature driver in the Arctic Basin, and plays a role in Global Temperatures as well.


Quote:
Quote:
This situation probably differs from the situation that existed in the early to mid-1990s, when enhanced ice export through Fram Strait was caused by anomalous winds associated with the positive Arctic Oscillation phase.



They refer to the situation being different from the Mid 1990s, because this is when the AMO turned positive.


But the paper does not deal with the conditions prior to that which would be required if it were discussing climate rather than shorter-term weather. A passing reference to a large cause does not catapult the paper into the realm of climate study as much as you seem to wish to make it appear as such.

Snowy123 wrote:

To my knowledge you have not referenced a single paper that deals with the AMO on this thread.


So you were mistaken again? :mrgreen: :lol:

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PostPosted: Wed Aug 22, 2012 8:19 am 
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http://www.bbc.co.uk/news/science-environment-19330307

Scientists at the US National Snow and Ice Data Center said data showed that the sea ice extent was tracking below the previous record low, set in 2007.

Latest figures show that on 13 August ice extent was 483,000 sq km (186,000 sq miles) below the previous record low for the same date five years ago.

The ice is expected to continue melting until mid- to late September.

"A new daily record... would be likely by the end of August," the centre's lead scientist, Ted Scambos, told Reuters
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