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PostPosted: Wed Apr 10, 2013 9:41 pm 
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Snowy123 wrote:
Wayne Stollings wrote:


So you expect all locations around the globe to have the same temperature pattern and if they do not you disbelieve them? I suppose that tells us a lot about the science education in the US.


Some of the proxies in the above image show completely opposite trends while others are in between. Like I said, I'm skeptical. You should be too.


Why would I be skeptical of different areas of the globe showing different trends especially given that some of the differences are not that different given the scales are not the same.

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PostPosted: Wed Apr 10, 2013 9:55 pm 
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The measured temperature compared to the sunspot activity in recent years does not correlate.

Image

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PostPosted: Wed Apr 10, 2013 10:04 pm 
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http://www.aanda.org/index.php?option=c ... 25-06.html


Reconstruction of solar total irradiance since 1700 from the surface magnetic flux

Image

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PostPosted: Thu Apr 11, 2013 6:40 am 
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Wayne Stollings wrote:
Snowy123 wrote:
Wayne Stollings wrote:


So you expect all locations around the globe to have the same temperature pattern and if they do not you disbelieve them? I suppose that tells us a lot about the science education in the US.


Some of the proxies in the above image show completely opposite trends while others are in between. Like I said, I'm skeptical. You should be too.


Why would I be skeptical of different areas of the globe showing different trends especially given that some of the differences are not that different given the scales are not the same.


Because those different areas of the globe show absolutely no relationship to each other in the proxies. That may be an indicator that the proxies are measuring something else other than temperature that is contaminating the results, which is entirely possible.

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PostPosted: Thu Apr 11, 2013 7:50 am 
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Wayne Stollings wrote:
The measured temperature compared to the sunspot activity in recent years does not correlate.

Image


There is a solar signature in the 20th Century and in recent temperature change.

Laptukhov and Laptukhov 2010

Based on large set of observational data (for ∼100 years), it has been demonstrated that the air temperature at midlatitudes in the years close to solar activity maximum is on average higher than in other years by DT = 0.11–0.15 degrees at many meteorological stations. The DT parameter is negative and smaller in magnitude near the equator and poles. A correct (in the energetic sense) physical mechanism by which solar and geomagnetic activities affect the ground level air temperature has been proposed.

This led the authors to speculate that the effect of Carbon Dioxide is not very important (though I disagree that it should be ignored).

Echer et al. 2012

The air surface temperature is a basic meteorological parameter and its variation is a primary measure of global, regional and local climate changes. In this work, the global, hemispheric and latitudinal averaged air surface temperature time series, obtained from the NASA/Goddard Institute for Space Studies (GISS), and the Sunspot Number (Rz) for the interval 1880–2005, are decomposed in frequency bands through wavelet multi-resolution analysis. We have found a very low correlation between global, hemispheric and latitudinal averaged air surface temperature and Rz in the 11 yr solar cycle band (8–16 years) from ∼1880 to ∼1950. Afterwards the correlation is higher. A very significant correlation (R ∼0.57 to 0.80) is found in the ∼22 yr solar Hale cycle band (16–32 years) with lags from zero to four years between latitudinal averages air surface temperature and Rz. Therefore it seems that the 22 yr magnetic field solar cycle might have a higher effect on Earth's climate than solar variations related to the 11 yr sunspot cycle.

Cho et al. 2012

We investigate whether the global temperature anomaly is associated with the solar North-South asymmetry using data archived approximately for five solar cycles. We are motivated by both the accumulating evidence for the connection of Galactic cosmic-rays (GCRs) to the cloud coverage and recent finding of the association of GCR influx and the solar North-South asymmetry. We have analyzed the data of the observed sunspot, the GCR influx observed at the Moscow station, and the global temperature anomaly. We have found that the mean global temperature anomaly is systematically smaller (∼0.56 in the unit of its standard deviation) during the period when the solar northern hemisphere is more active than the solar southern hemisphere. The difference in the mean value of the global temperature anomaly for the two data sets sub-sampled according to the solar North-South asymmetry is large and statistically significant. We suggest the solar North-South asymmetry is related to the global temperature anomaly through modulating the amount of GCR influx. Finally, we conclude by discussing its implications on a climate model and a direction of future work.

Your claim is that because the Sunspot Number was flat over the last 30 years, the sun could not have contributed to Global Warming during this timeframe. The role of equilibrium needs to be considered, but even accounting for equilibrium does not give a large solar contribution over the late-20th Century. However, if more adequate solar indicies like the Geomagnetic AA Index are used, a larger portion of the warming can be explained by solar activity.

We can see in this figure from Georgieva et al. 2012 that while the SSN was declining, the AA Index continued to increase, allowing for more of the warming to be explained by solar variance.

Image

I've been doing some research on solar activity and temperature change on Google Scholar, and I am actually surprised at the number of papers that support a skeptical position. Arguably, there are just as many papers that I've seen on Google Scholar that support a strong solar effect on temperatures, as there are that do not support a strong solar effect. Most of the claims that do not support a large solar forcing are because they only account for solar irradiance and claim that the amplitude of the recent warming during the 20th Century was insufficient to be explained by solar effects. Accounting for any solar effects on cloud cover can easily give a large solar contribution to the 20th Century warming observed.

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Last edited by Snowy123 on Thu Apr 11, 2013 8:04 am, edited 3 times in total.

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PostPosted: Thu Apr 11, 2013 7:50 am 
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That's not to say that Carbon Dioxide and other anthropogenic influences do not significantly impact temperature changes, but the solar effect is often ignored, and there is a good deal of literature that supports a more significant role of the sun in recent Global Warming over the 20th Century.

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Last edited by Snowy123 on Thu Apr 11, 2013 7:59 am, edited 1 time in total.

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PostPosted: Thu Apr 11, 2013 7:59 am 
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Wayne Stollings wrote:
http://www.aanda.org/index.php?option=com_article&access=standard&Itemid=129&url=/articles/aa/full/2007/19/aa6725-06/aa6725-06.html


Reconstruction of solar total irradiance since 1700 from the surface magnetic flux

Image


Krivova et al. 2007 shows yet another TSI reconstruction through a magnetic flux model. It is mentioned in the comments that it disagrees with previous larger estimates of a TSI change in previous work, like from Lockwood et al. 1999 and Lean et al. 1995.

Interesting. Goes to show that we still have some uncertainty regarding TSI reconstructions.

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PostPosted: Thu Apr 11, 2013 8:22 am 
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Wayne Stollings wrote:
Snowy123 wrote:
Wayne Stollings wrote:


So you expect all locations around the globe to have the same temperature pattern and if they do not you disbelieve them? I suppose that tells us a lot about the science education in the US.


Some of the proxies in the above image show completely opposite trends while others are in between. Like I said, I'm skeptical. You should be too.


Why would I be skeptical of different areas of the globe showing different trends especially given that some of the differences are not that different given the scales are not the same.


Snowy123 wrote:
Because those different areas of the globe show absolutely no relationship to each other in the proxies.



That would not be an accurate statement since some of them do show similar trends and there were about three times that number of proxy sites used.

Quote:
That may be an indicator that the proxies are measuring something else other than temperature that is contaminating the results, which is entirely possible.


If you looked at the trends for different areas of the globe today you could see similar variations. The proxy sources were not created by this research but are sources which have been used and reviewed by other researchers. The "may be possible" opposition is less than weak at this point in time.

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PostPosted: Thu Apr 11, 2013 8:28 am 
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Snowy123 wrote:
Wayne Stollings wrote:
The measured temperature compared to the sunspot activity in recent years does not correlate.

Image


There is a solar signature in the 20th Century and in recent temperature change.

Laptukhov and Laptukhov 2010

Based on large set of observational data (for ∼100 years), it has been demonstrated that the air temperature at midlatitudes in the years close to solar activity maximum is on average higher than in other years by DT = 0.11–0.15 degrees at many meteorological stations. The DT parameter is negative and smaller in magnitude near the equator and poles. A correct (in the energetic sense) physical mechanism by which solar and geomagnetic activities affect the ground level air temperature has been proposed.

This led the authors to speculate that the effect of Carbon Dioxide is not very important (though I disagree that it should be ignored).

Echer et al. 2012

The air surface temperature is a basic meteorological parameter and its variation is a primary measure of global, regional and local climate changes. In this work, the global, hemispheric and latitudinal averaged air surface temperature time series, obtained from the NASA/Goddard Institute for Space Studies (GISS), and the Sunspot Number (Rz) for the interval 1880–2005, are decomposed in frequency bands through wavelet multi-resolution analysis. We have found a very low correlation between global, hemispheric and latitudinal averaged air surface temperature and Rz in the 11 yr solar cycle band (8–16 years) from ∼1880 to ∼1950. Afterwards the correlation is higher. A very significant correlation (R ∼0.57 to 0.80) is found in the ∼22 yr solar Hale cycle band (16–32 years) with lags from zero to four years between latitudinal averages air surface temperature and Rz. Therefore it seems that the 22 yr magnetic field solar cycle might have a higher effect on Earth's climate than solar variations related to the 11 yr sunspot cycle.

Cho et al. 2012

We investigate whether the global temperature anomaly is associated with the solar North-South asymmetry using data archived approximately for five solar cycles. We are motivated by both the accumulating evidence for the connection of Galactic cosmic-rays (GCRs) to the cloud coverage and recent finding of the association of GCR influx and the solar North-South asymmetry. We have analyzed the data of the observed sunspot, the GCR influx observed at the Moscow station, and the global temperature anomaly. We have found that the mean global temperature anomaly is systematically smaller (∼0.56 in the unit of its standard deviation) during the period when the solar northern hemisphere is more active than the solar southern hemisphere. The difference in the mean value of the global temperature anomaly for the two data sets sub-sampled according to the solar North-South asymmetry is large and statistically significant. We suggest the solar North-South asymmetry is related to the global temperature anomaly through modulating the amount of GCR influx. Finally, we conclude by discussing its implications on a climate model and a direction of future work.

Your claim is that because the Sunspot Number was flat over the last 30 years, the sun could not have contributed to Global Warming during this timeframe. The role of equilibrium needs to be considered, but even accounting for equilibrium does not give a large solar contribution over the late-20th Century. However, if more adequate solar indicies like the Geomagnetic AA Index are used, a larger portion of the warming can be explained by solar activity.

We can see in this figure from Georgieva et al. 2012 that while the SSN was declining, the AA Index continued to increase, allowing for more of the warming to be explained by solar variance.

Image

I've been doing some research on solar activity and temperature change on Google Scholar, and I am actually surprised at the number of papers that support a skeptical position. Arguably, there are just as many papers that I've seen on Google Scholar that support a strong solar effect on temperatures, as there are that do not support a strong solar effect. Most of the claims that do not support a large solar forcing are because they only account for solar irradiance and claim that the amplitude of the recent warming during the 20th Century was insufficient to be explained by solar effects. Accounting for any solar effects on cloud cover can easily give a large solar contribution to the 20th Century warming observed.


There is a correlation between solar output and temperature, however the trends diverge more and more as they approach the current time period.

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PostPosted: Thu Apr 11, 2013 8:31 am 
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Snowy123 wrote:
Wayne Stollings wrote:
http://www.aanda.org/index.php?option=com_article&access=standard&Itemid=129&url=/articles/aa/full/2007/19/aa6725-06/aa6725-06.html


Reconstruction of solar total irradiance since 1700 from the surface magnetic flux

Image


Krivova et al. 2007 shows yet another TSI reconstruction through a magnetic flux model. It is mentioned in the comments that it disagrees with previous larger estimates of a TSI change in previous work, like from Lockwood et al. 1999 and Lean et al. 1995.

Interesting. Goes to show that we still have some uncertainty regarding TSI reconstructions.


It sounds almost as if you are supporting a determination made by a new model .......

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PostPosted: Thu Apr 11, 2013 8:32 am 
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Wayne Stollings wrote:
If you looked at the trends for different areas of the globe today you could see similar variations. The proxy sources were not created by this research but are sources which have been used and reviewed by other researchers. The "may be possible" opposition is less than weak at this point in time.


It's possible that there are discrepencies with local regions compared to the overall warming trend. The Arctic is warming faster than the Global Warming trend, and the Antarctic Warming trend is considerably less than the Global Warming trend over the last 30 years. However, there are not areas in the Globe during this current warming period that has a 2 Degree C warming and another area that has a 2 Degree C cooling. That's why I'm skeptical. Though it is interesting to see the proxy data line up with the instrumental data when the average of all of the data is considered. However, it could simply be just a coincidence given that there are wide extremes in the individual proxy data on both sides of the envelope.

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PostPosted: Thu Apr 11, 2013 8:36 am 
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Wayne Stollings wrote:
Snowy123 wrote:
Wayne Stollings wrote:
The measured temperature compared to the sunspot activity in recent years does not correlate.

Image


There is a solar signature in the 20th Century and in recent temperature change.

Laptukhov and Laptukhov 2010

Based on large set of observational data (for ∼100 years), it has been demonstrated that the air temperature at midlatitudes in the years close to solar activity maximum is on average higher than in other years by DT = 0.11–0.15 degrees at many meteorological stations. The DT parameter is negative and smaller in magnitude near the equator and poles. A correct (in the energetic sense) physical mechanism by which solar and geomagnetic activities affect the ground level air temperature has been proposed.

This led the authors to speculate that the effect of Carbon Dioxide is not very important (though I disagree that it should be ignored).

Echer et al. 2012

The air surface temperature is a basic meteorological parameter and its variation is a primary measure of global, regional and local climate changes. In this work, the global, hemispheric and latitudinal averaged air surface temperature time series, obtained from the NASA/Goddard Institute for Space Studies (GISS), and the Sunspot Number (Rz) for the interval 1880–2005, are decomposed in frequency bands through wavelet multi-resolution analysis. We have found a very low correlation between global, hemispheric and latitudinal averaged air surface temperature and Rz in the 11 yr solar cycle band (8–16 years) from ∼1880 to ∼1950. Afterwards the correlation is higher. A very significant correlation (R ∼0.57 to 0.80) is found in the ∼22 yr solar Hale cycle band (16–32 years) with lags from zero to four years between latitudinal averages air surface temperature and Rz. Therefore it seems that the 22 yr magnetic field solar cycle might have a higher effect on Earth's climate than solar variations related to the 11 yr sunspot cycle.

Cho et al. 2012

We investigate whether the global temperature anomaly is associated with the solar North-South asymmetry using data archived approximately for five solar cycles. We are motivated by both the accumulating evidence for the connection of Galactic cosmic-rays (GCRs) to the cloud coverage and recent finding of the association of GCR influx and the solar North-South asymmetry. We have analyzed the data of the observed sunspot, the GCR influx observed at the Moscow station, and the global temperature anomaly. We have found that the mean global temperature anomaly is systematically smaller (∼0.56 in the unit of its standard deviation) during the period when the solar northern hemisphere is more active than the solar southern hemisphere. The difference in the mean value of the global temperature anomaly for the two data sets sub-sampled according to the solar North-South asymmetry is large and statistically significant. We suggest the solar North-South asymmetry is related to the global temperature anomaly through modulating the amount of GCR influx. Finally, we conclude by discussing its implications on a climate model and a direction of future work.

Your claim is that because the Sunspot Number was flat over the last 30 years, the sun could not have contributed to Global Warming during this timeframe. The role of equilibrium needs to be considered, but even accounting for equilibrium does not give a large solar contribution over the late-20th Century. However, if more adequate solar indicies like the Geomagnetic AA Index are used, a larger portion of the warming can be explained by solar activity.

We can see in this figure from Georgieva et al. 2012 that while the SSN was declining, the AA Index continued to increase, allowing for more of the warming to be explained by solar variance.

Image

I've been doing some research on solar activity and temperature change on Google Scholar, and I am actually surprised at the number of papers that support a skeptical position. Arguably, there are just as many papers that I've seen on Google Scholar that support a strong solar effect on temperatures, as there are that do not support a strong solar effect. Most of the claims that do not support a large solar forcing are because they only account for solar irradiance and claim that the amplitude of the recent warming during the 20th Century was insufficient to be explained by solar effects. Accounting for any solar effects on cloud cover can easily give a large solar contribution to the 20th Century warming observed.


There is a correlation between solar output and temperature, however the trends diverge more and more as they approach the current time period.


Carbon Dioxide or Solar Activity alone can not explain all of the warming. However, it is entirely possible that most of the warming over the 20th Century has been caused by Solar Activity. What is certain in my opinion, is that there is a significant contribution from solar activity to the warming trend. Whether it's 33%, 60% or 85% is uncertain, but there has been a large solar effect on the warming over the last 100-150 years.

Multidecadal variability accentuating or masking the long term warming trend should also be considered when looking at how much of a discrepency there is with solar activity, carbon dioxide and temperatures. For example, Wu et al. 2012 estimated that about a third of the late-20th Century warming can be explained from natural variability from oceanic cycles. Even if solar activity contributed to around 30% of the late-20th Century Warming (which is about the contribution Solanki and Krivova argue), it would still question the IPCC statement that most of the warming since 1950 is very likely due to Greenhouse Gas Emissions.

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PostPosted: Thu Apr 11, 2013 8:43 am 
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Wayne Stollings wrote:
Snowy123 wrote:
Wayne Stollings wrote:
http://www.aanda.org/index.php?option=com_article&access=standard&Itemid=129&url=/articles/aa/full/2007/19/aa6725-06/aa6725-06.html


Reconstruction of solar total irradiance since 1700 from the surface magnetic flux

Image


Krivova et al. 2007 shows yet another TSI reconstruction through a magnetic flux model. It is mentioned in the comments that it disagrees with previous larger estimates of a TSI change in previous work, like from Lockwood et al. 1999 and Lean et al. 1995.

Interesting. Goes to show that we still have some uncertainty regarding TSI reconstructions.


It sounds almost as if you are supporting a determination made by a new model .......


It definitely has it's limits. I'm not totally dismissing it though. I would definitely rather prefer observational reconstructions from C14 and Be10 isotopes though.

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PostPosted: Thu Apr 11, 2013 10:48 am 
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Wayne Stollings wrote:
Snowy123 wrote:
Wayne Stollings wrote:
The measured temperature compared to the sunspot activity in recent years does not correlate.

Image


There is a solar signature in the 20th Century and in recent temperature change.

Laptukhov and Laptukhov 2010

Based on large set of observational data (for ∼100 years), it has been demonstrated that the air temperature at midlatitudes in the years close to solar activity maximum is on average higher than in other years by DT = 0.11–0.15 degrees at many meteorological stations. The DT parameter is negative and smaller in magnitude near the equator and poles. A correct (in the energetic sense) physical mechanism by which solar and geomagnetic activities affect the ground level air temperature has been proposed.

This led the authors to speculate that the effect of Carbon Dioxide is not very important (though I disagree that it should be ignored).

Echer et al. 2012

The air surface temperature is a basic meteorological parameter and its variation is a primary measure of global, regional and local climate changes. In this work, the global, hemispheric and latitudinal averaged air surface temperature time series, obtained from the NASA/Goddard Institute for Space Studies (GISS), and the Sunspot Number (Rz) for the interval 1880–2005, are decomposed in frequency bands through wavelet multi-resolution analysis. We have found a very low correlation between global, hemispheric and latitudinal averaged air surface temperature and Rz in the 11 yr solar cycle band (8–16 years) from ∼1880 to ∼1950. Afterwards the correlation is higher. A very significant correlation (R ∼0.57 to 0.80) is found in the ∼22 yr solar Hale cycle band (16–32 years) with lags from zero to four years between latitudinal averages air surface temperature and Rz. Therefore it seems that the 22 yr magnetic field solar cycle might have a higher effect on Earth's climate than solar variations related to the 11 yr sunspot cycle.

Cho et al. 2012

We investigate whether the global temperature anomaly is associated with the solar North-South asymmetry using data archived approximately for five solar cycles. We are motivated by both the accumulating evidence for the connection of Galactic cosmic-rays (GCRs) to the cloud coverage and recent finding of the association of GCR influx and the solar North-South asymmetry. We have analyzed the data of the observed sunspot, the GCR influx observed at the Moscow station, and the global temperature anomaly. We have found that the mean global temperature anomaly is systematically smaller (∼0.56 in the unit of its standard deviation) during the period when the solar northern hemisphere is more active than the solar southern hemisphere. The difference in the mean value of the global temperature anomaly for the two data sets sub-sampled according to the solar North-South asymmetry is large and statistically significant. We suggest the solar North-South asymmetry is related to the global temperature anomaly through modulating the amount of GCR influx. Finally, we conclude by discussing its implications on a climate model and a direction of future work.

Your claim is that because the Sunspot Number was flat over the last 30 years, the sun could not have contributed to Global Warming during this timeframe. The role of equilibrium needs to be considered, but even accounting for equilibrium does not give a large solar contribution over the late-20th Century. However, if more adequate solar indicies like the Geomagnetic AA Index are used, a larger portion of the warming can be explained by solar activity.

We can see in this figure from Georgieva et al. 2012 that while the SSN was declining, the AA Index continued to increase, allowing for more of the warming to be explained by solar variance.

Image

I've been doing some research on solar activity and temperature change on Google Scholar, and I am actually surprised at the number of papers that support a skeptical position. Arguably, there are just as many papers that I've seen on Google Scholar that support a strong solar effect on temperatures, as there are that do not support a strong solar effect. Most of the claims that do not support a large solar forcing are because they only account for solar irradiance and claim that the amplitude of the recent warming during the 20th Century was insufficient to be explained by solar effects. Accounting for any solar effects on cloud cover can easily give a large solar contribution to the 20th Century warming observed.


There is a correlation between solar output and temperature, however the trends diverge more and more as they approach the current time period.


Snowy123 wrote:
Carbon Dioxide or Solar Activity alone can not explain all of the warming. However, it is entirely possible that most of the warming over the 20th Century has been caused by Solar Activity. What is certain in my opinion, is that there is a significant contribution from solar activity to the warming trend. Whether it's 33%, 60% or 85% is uncertain, but there has been a large solar effect on the warming over the last 100-150 years.

Multidecadal variability accentuating or masking the long term warming trend should also be considered when looking at how much of a discrepency there is with solar activity, carbon dioxide and temperatures. For example, Wu et al. 2012 estimated that about a third of the late-20th Century warming can be explained from natural variability from oceanic cycles. Even if solar activity contributed to around 30% of the late-20th Century Warming (which is about the contribution Solanki and Krivova argue), it would still question the IPCC statement that most of the warming since 1950 is very likely due to Greenhouse Gas Emissions.


So one scientist's opinion combined with anther scientist's opinion is supposed to carry more weight when compared to a group of scientist's opinion when they are all experts in their fields, why?

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PostPosted: Thu Apr 11, 2013 10:51 am 
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Wayne Stollings wrote:
Snowy123 wrote:
Wayne Stollings wrote:
http://www.aanda.org/index.php?option=com_article&access=standard&Itemid=129&url=/articles/aa/full/2007/19/aa6725-06/aa6725-06.html


Reconstruction of solar total irradiance since 1700 from the surface magnetic flux

Image


Krivova et al. 2007 shows yet another TSI reconstruction through a magnetic flux model. It is mentioned in the comments that it disagrees with previous larger estimates of a TSI change in previous work, like from Lockwood et al. 1999 and Lean et al. 1995.

Interesting. Goes to show that we still have some uncertainty regarding TSI reconstructions.


It sounds almost as if you are supporting a determination made by a new model .......


Snowy123 wrote:
It definitely has it's limits. I'm not totally dismissing it though. I would definitely rather prefer observational reconstructions from C14 and Be10 isotopes though.


Assuming those proxy measurements are accurate and correct, of course.

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