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PostPosted: Fri Sep 30, 2011 2:03 pm 
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PostPosted: Fri Mar 02, 2012 6:56 am 
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Thanks for sharing awareness.


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PostPosted: Mon Apr 30, 2012 3:53 am 
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The points raised in this thread are addressed in the NAS final report.


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PostPosted: Fri May 25, 2012 5:28 pm 
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I have revised my views slightly since I began this thread.

A decrease in Cloud Cover is responsible for most of the warming over the last 30 years and last century, and this decrease in Cloud Cover is directly tied to solar activity variations through solar wind variations inflicting changes on GCRs.

There is an overwhelming amount of evidence to support this viewpoint.

Let's start with nine peer reviewed studies that document that the sun was a likely driver of the 20th Century Warming.

Palle Bago and Butler 2001
Palle Bago and Butler 2001, using many formulas they derived in their earlier, 2000 paper, calculated that the solar effects, directly and indirectly, caused 0.5 Degrees C of the 0.55 Degree C warming. This means that they found that 91% of the warming over the past 100 years can be explained by solar variability, directly and indirectly alone. They mention that there is a "possibility" that solar attribution could be less during the most recent decades, but they are not definite with this statement. They simply state that the solar contribution an unknown over the last and most recent decades. This probably has to do with the ACRIM and PMOD TSI Composites and the controversy surrounding these datasets which Scafetta 2009 documents.

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Georgieva et. al 2005
Georgieva et. al 2005 used the Geomagnetic AA Index to quantify the solar impact on Climate Change, rather than the sunspot number, because using the sunspot number to quantify the solar contribution to climate change, as many studies do, leads to an underestimation of the Solar impact on Climate Change.


Image

The above figure from Georgieva et. al shows the Geomagentic AA Index with the broken line, and the Global Temperature Anomalies with the solid line. They find that the correlation coefficient between the AA Index and Global Temperatures is 0.85, meaning that the sun can explain 85% of the variances in temperatures over the last ~150 years.


Cliver et. al 1998
Cliver et. al 1998 also used the Geomagnetic AA Index to estimate the solar contribution to climate change.


Image

Above figure: From Cliver et. al 1998. The AA Index is the dotted line, and the solid line are the temperature anomalies.

They found that 50-100% of the warming could be due to the sun, but it should be noted that this analysis does not include other factors like volcanic activity and anthropogenic greenhouse gas emissions when estimating the total contribution. Nonetheless, this study also shows that other studies which do include these factors are only at the lower end of the 50-100% range for the solar contribution over the last 100-150 years. It also supports other studies with a larger solar contribution to climate change because of the remarkable correlation with the AA Index and temperatures.


Solheim et. al 2012
Solheim et. al 2012 found that the solar signal is reinforced by the Atlantic Ocean, and this reinforcing signal in the Atlantic Ocean is calculated to be from 63-72% of the variances in temperatures over the entire timeframe. They get a lower solar contribution to land based stations, but the reinforced signal is probably what would lead to a more accurate solar contribution, since most of the world is covered by oceans, and likely, reinforcing the solar signals.


Link et. al 2011
The box that represents the % solar contribution from Link et. al 2011 actually represents the probability whether the entire trend over the last 100-150 years is natural. The authors calculate that the probability of the warming being caused by solar activity over this entire timeframe is 40-90%. It should be noted that these probabilities go up significantly over shorter timeframes like 1900-1950 and 1960-2005.


Scafetta and West 2008
Scafetta and West 2008 adresses the uncertainty raised in the first paper. If a TSI curve that shows an upward trend from Solar Cycle 21 to 22 is used from the ACRIM TSI composite rather than the flat PMOD TSI composite, then a higher contribution from the sun would be needed. The authors find that up to 69% of the variances in temperatures can be explained by solar activity.

Image


The image above from Scafetta and West 2008 shows the divergence between the PMOD and ACRIM TSI datasets, which makes attribution to past climate change even harder. The red curve is the ACRIM TSI composite, the blue curve is the PMOD TSI Composite, and the black curve and green line are the Global Temperature anomalies.


Scafetta and West 2007
The ACRIM verses PMOD controversy continues in this paper. 50% or more of temperatures can be attributed to the solar forcing, depending if the ACRIM TSI composite is used or not. This further adds on to resolving the uncertainty between the PMOD and ACRIM datasets during the ACRIM Gap.


Image


The graph above from Scafetta and West 2007 shows the excellent correlation between solar activity and temperatures. It also shows that a large portion of the warming can be attributed to solar activity. Over the last 30 years, a significant portion of the warming can be attributed to solar activity if the ACRIM TSI composite is used.




Ogurtsov 2007
Ogurstov 2007 estimated that the solar contribution directly and indirectly caused about 0.25-0.35 degrees C of the warming that took place during the 20th Century. Using the Skeptical Science trend calculator gives an approxiate warming of 0.6 Degrees C during the 20th Century. This means that 41-59% of the trend upward can be attributed to solar activity over the past 100 years.

Blanter et. al 2008

Blanter et. al 2008 found that temperatures correlated remarkably well for all periods between the solar activity indicies and the observed temperatures for stations in Europe and the United States during the 20th Century. They used a finding from a previous study that the temperatures at weather stations correlated remarkably well if they were up to a 1000 km distance from each other. They also state in the abstract that these changes can "possibly" be extended onto a Global scale. Being that they found that solar activity can account for all temperature changes over the 20th Century, I reduced the range slightly from 100% to somwhere in the 90-100% range to account for the anthropogenic forcings.

I will be posting more papers later on this thread that support a natural solar and oceanic cause for recent warming, and not anthropogenic.

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PostPosted: Fri May 25, 2012 6:12 pm 
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Wayne Stollings wrote:
You miss the obvious, if ISR increases the temperature can increase along with an increase in OLR. The solar output fluctuates a few percentage points too.

Image


This image does not account for the GCR-Cloud Feedback, and underestimates the solar influence, because it only accounts for TSI. There are many other ways the sun impacts climate other than it's irradiance. It's magnetic field, solar proton storms, and GCRs are a few.

It also doesn't take the true sensitivity of CO2 into consideration.

Image

The image above shows 7 temperature variations and the energy imbalances of Earth as measured by the TERRA satellite from 2000-2007. It shows two variations: Radiative spirals and linear feedback striations. The radiative spirals (primarily from the Cloud Forcing) bring the slope of the regression line closer to zero, which would give the illusion of a more sensitive climate system than how sensitive it actually is. A steeper positive slope would indicate a more insensitive climate system, and a slope greater than 3.3 w/m^2/Degree C would indicate that negative feedback exists in Earth's Climate, since this is the rate at which Earth radiates to space per Degree celcius change, and a higher slope would indicate that there are mechanisms allowing for more energy to be radiated out to space. In Dr. Spencer's analysis, he found that the linear feedback striations are characterized by non-radiative forcing changes, so there would be no contamination from the radiative forcing spirals in these feedback striations. The true sensitivity of the climate system can be taken through the slope of the linear feedback striations.

You get a VERY strong negative feedback, which would correspond to a value of 0.46 Degrees C per CO2 doubling. (Source: http://www.drroyspencer.com/research-ar ... -evidence/)

Other satellites used in Dr. Spencer's analysis give a slightly higher value of around 0.6 Degrees C, but Dr. Spencer notes that these values could be an overestimation.

"What this means is that the line slopes diagnosed from the satellite data in Fig. 4 might actually be an UNDERESTIMATE of the true feedback occurring, which could be 7 W m-2 K-1 or more."

So the anthropogenic forcing on that chart is highly exaggerated, and is likely not even 0.2 Degrees C, if one is to take the feedback estimation from the TERRA satellite.

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PostPosted: Fri May 25, 2012 8:16 pm 
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Snowy123 wrote:
Wayne Stollings wrote:
You miss the obvious, if ISR increases the temperature can increase along with an increase in OLR. The solar output fluctuates a few percentage points too.

Image


This image does not account for the GCR-Cloud Feedback, and underestimates the solar influence, because it only accounts for TSI.


Assuming there were significant GCR-Cloud feedbacks, which is unsupported by the evidence.


Quote:
There are many other ways the sun impacts climate other than it's irradiance. It's magnetic field, solar proton storms, and GCRs are a few.


The evidence for causation of those impacts is where?

Quote:
It also doesn't take the true sensitivity of CO2 into consideration.


Assuming, again, the "true" sensitivity is what you believe it to be.

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PostPosted: Sat May 26, 2012 11:34 am 
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Wayne Stollings wrote:

Assuming there were significant GCR-Cloud feedbacks, which is unsupported by the evidence.


Hmm. Indeed.

GCRs have been shown to produce small particles that can grow to 50 nm, which is sufficient for Cloud Condensation Nuclei.

Enghoff et. al 2012

In experiments where ultraviolet light produces aerosols from trace amounts of ozone, sulphur
dioxide, and water vapour, the number of additional small particles produced by ionization by
gamma sources all grow up to diameters larger than 50 nm, appropriate for cloud condensation
nuclei
.


They signficiantly impact aerosoles, which can be seen during Forbush Decreases.

They also impact the DTR range substantially, which is seen during Forbush Decreases.

The impact of the Forbush Decrease was recognized as early as 1995, with decreases in precipitation associated with FDs.

For a sample of papers supporting that GCRs have a signficant influence on Clouds, leading to a significant influence on climate.

There are many papers which point to GCRs as being a possible climate driver over paleoclimatic history, amplifying whatever changes occur with the sun, and changes in GCRs associated with the spirals of the milky way.

Quote:
The evidence for causation of those impacts is where?


Let's start with this paper.

http://www.nat-hazards-earth-syst-sci.n ... 3-2002.pdf

And this paper:

http://www.agu.org/pubs/crossref/2011/2 ... 5822.shtml

It's amazing that some claim that the sun has little to no impact on climate change, when there are SO many ways the sun and it's feedbacks (GCRs) impact the atmosphere of the Earth.

http://www.sciencedaily.com/releases/20 ... 080620.htm

"Solar proton events help us test our models," Jackman said. "This is an instance where we have a huge natural variance. You have to first be able to separate the natural effects on ozone, before you can tease out human-kind's impacts."

Quote:
Assuming, again, the "true" sensitivity is what you believe it to be.


It is the view held by many top atmospheric physicists, who are experts in this particular topic of climate change.

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Last edited by Snowy123 on Sat May 26, 2012 12:01 pm, edited 1 time in total.

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PostPosted: Sat May 26, 2012 11:57 am 
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This post will focus on the fact that we don't know enough to fully determine what caused the warming or not.

There are still large uncertainties in climate science that still need to be resolved. Cloud and Water Vapor feedbacks are one of these VERY high uncertainties, as well as temperature attribution over the last 100 or so years.

These honest climate scientists feel that there is so much uncertainty still left, that it is unclear how much of the recent (last 30 years) is natural.

Compo et. al 2009 finds that changes in the changes in the SSTs have led to temperature changes over land- not GHGs directly. The oceans themselves have warmed from a combination of natural and anthropogenic causes over the recent warming, they say, but it is unclear which has contributed more than the other.

Duplissy et. al 2010

In its Fourth Assessment Report, 2007, the Intergovernmental
Panel on Climate Change (IPCC) attributes more than
90% of the observed climate warming since 1900 to the rise
of anthropogenic greenhouse gases in the atmosphere (IPCC,
2007). Aerosols and clouds are recognised as representing
the largest uncertainty in the current understanding of climate
change. The IPCC estimates that changes of solar irradiance
(direct solar forcing) have made only a small (7%)
contribution to the observed warming. However, large uncertainties
remain on other solar-related contributions, such
as the effects of changes of ultra-violet (UV) radiation or
galactic cosmic rays on aerosols and clouds


Fang et. al 2011

In recent decades, there have been a number of debates on climate warming and its driving forces. Based on an extensive literature review, we suggest that (1) climate warming occurs with great uncertainty in the magnitude of the temperature increase; (2) both human activities and natural forces contribute to climate change, but their relative contributions are difficult to quantify; and (3) the dominant role of the increase in the atmospheric concentration of greenhouse gases (including CO2) in the global warming claimed by the Intergovernmental Panel on Climate Change (IPCC) is questioned by the scientific communities because of large uncertainties in the mechanisms of natural factors and anthropogenic activities and in the sources of the increased atmospheric CO2 concentration. More efforts should be made in order to clarify these uncertainties.

I will have more papers adressing the natural variability and solar aspect of the natural contributors.

To say that the cause is anthropogenic, as claimed by the IPCC, is not scientifically correct, since there remain large uncertainties with natural contributions and the evidence for natural causes as having a significant, and dominant contribution to the late-20th Century warming is VERY high, as well as causing the warming over the last 100-150 years.

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PostPosted: Sat May 26, 2012 11:59 am 
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Image

For the nine solar studies I posted a few posts back.

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PostPosted: Sat May 26, 2012 12:02 pm 
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Snowy123 wrote:
Wayne Stollings wrote:

Assuming there were significant GCR-Cloud feedbacks, which is unsupported by the evidence.


Hmm. Indeed.

GCRs have been shown to produce small particles that can grow to 50 nm, which is sufficient for Cloud Condensation Nuclei.

Enghoff et. al 2012

In experiments where ultraviolet light produces aerosols from trace amounts of ozone, sulphur
dioxide, and water vapour, the number of additional small particles produced by ionization by
gamma sources all grow up to diameters larger than 50 nm, appropriate for cloud condensation
nuclei
.


Given there are prior experiments which contradict this position, as the paper acknowledges, in addition to theoretical models, there will have to be some reproduction by independent sources before there is any support for this view.

This result contradicts both ion-free control experiments and also theoretical models that
predict a decline in the response of larger particles due to an insufficiency of condensable gases


Quote:
(which leads to slower growth) and to larger losses by coagulation between the particles.


They signficiantly impact aerosoles, which can be seen during Forbush Decreases.

They alsoimpact the DTR range substantially, which is seen during Forbush Decreases.

The impact of the Forbush Decrease was recognized as early as 1995, with decreases in precipitation associated with FDs.


Correlation is not causation and the mechanism was not supported by the CERN experiments, which carry a little more weight than the experiments referenced unless there is a reproduction of results.


Quote:
For a sample of papers supporting that GCRs have a signficant influence on Clouds, leading to a significant influence on climate.

There are many papers which point to GCRs as being a possible climate driver over paleoclimatic history, amplifying whatever changes occur with the sun, and changes in GCRs associated with the spirals of the milky way.


Possible, yes. Major, probably not given the evidence.

Quote:
The evidence for causation of those impacts is where?


Quote:
Let's start with this paper.

http://www.nat-hazards-earth-syst-sci.n ... 3-2002.pdf

And this paper:

http://www.agu.org/pubs/crossref/2011/2 ... 5822.shtml

It's amazing that some claim that the sun has little to no impact on climate change, when there are SO many ways the sun and it's feedbacks (GCRs) impact the atmosphere of the Earth.

http://www.sciencedaily.com/releases/20 ... 080620.htm

"Solar proton events help us test our models," Jackman said. "This is an instance where we have a huge natural variance. You have to first be able to separate the natural effects on ozone, before you can tease out human-kind's impacts."


Correlation is not causation. The mechanisms by which some of these impacts could manifest themselves have little support in evidence.



Quote:
Quote:
Assuming, again, the "true" sensitivity is what you believe it to be.


It is the view held by many top atmospheric physicists, who are experts in this particular topic of climate change.


Many? Not a reference to a concensus is that? :mrgreen:

I believe there are also many who do not hold that belief given the experimental evidence to date.

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PostPosted: Sat May 26, 2012 12:07 pm 
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I have been responding during rest breaks from installing hardwood flooring in the downstairs master bedroom, but it is starting to slow my progress and I only have the weekend. With that in mind I will reply when I have stopped for the day .... provided I am still able to do so. I really hate installing hardwood because it really did a number on my wrist then elbow and finally shoulder the last time, but I could not have installed the travertine tile in the livingroom this weekend either.

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PostPosted: Sat May 26, 2012 12:08 pm 
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Wayne Stollings wrote:
...

Well that's because there is no such consensus on the subject. 8)

Yes there are many who disagree with these findings, just as there are many who support the hypothesis.

The debate is not over by any means.

There is no "fingerprint" of GHG warming, since there are other factors that can explain such "fingerprints" for GHG warming.

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PostPosted: Sat May 26, 2012 12:10 pm 
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Wayne Stollings wrote:
I have been responding during rest breaks from installing hardwood flooring in the downstairs master bedroom, but it is starting to slow my progress and I only have the weekend. With that in mind I will reply when I have stopped for the day .... provided I am still able to do so. I really hate installing hardwood because it really did a number on my wrist then elbow and finally shoulder the last time, but I could not have installed the travertine tile in the livingroom this weekend either.


That's totally fine, Wayne. Take your time, and good luck. It will still be fine if it takes you 40 years to reply to this :mrgreen:

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PostPosted: Sun May 27, 2012 5:34 am 
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Snowy123 wrote:
This post will focus on the fact that we don't know enough to fully determine what caused the warming or not.

There are still large uncertainties in climate science that still need to be resolved. Cloud and Water Vapor feedbacks are one of these VERY high uncertainties, as well as temperature attribution over the last 100 or so years.

These honest climate scientists feel that there is so much uncertainty still left, that it is unclear how much of the recent (last 30 years) is natural.

Compo et. al 2009 finds that changes in the changes in the SSTs have led to temperature changes over land- not GHGs directly. The oceans themselves have warmed from a combination of natural and anthropogenic causes over the recent warming, they say, but it is unclear which has contributed more than the other.

Duplissy et. al 2010

In its Fourth Assessment Report, 2007, the Intergovernmental
Panel on Climate Change (IPCC) attributes more than
90% of the observed climate warming since 1900 to the rise
of anthropogenic greenhouse gases in the atmosphere (IPCC,
2007). Aerosols and clouds are recognised as representing
the largest uncertainty in the current understanding of climate
change. The IPCC estimates that changes of solar irradiance
(direct solar forcing) have made only a small (7%)
contribution to the observed warming. However, large uncertainties
remain on other solar-related contributions, such
as the effects of changes of ultra-violet (UV) radiation or
galactic cosmic rays on aerosols and clouds


Fang et. al 2011

In recent decades, there have been a number of debates on climate warming and its driving forces. Based on an extensive literature review, we suggest that (1) climate warming occurs with great uncertainty in the magnitude of the temperature increase; (2) both human activities and natural forces contribute to climate change, but their relative contributions are difficult to quantify; and (3) the dominant role of the increase in the atmospheric concentration of greenhouse gases (including CO2) in the global warming claimed by the Intergovernmental Panel on Climate Change (IPCC) is questioned by the scientific communities because of large uncertainties in the mechanisms of natural factors and anthropogenic activities and in the sources of the increased atmospheric CO2 concentration. More efforts should be made in order to clarify these uncertainties.

I will have more papers adressing the natural variability and solar aspect of the natural contributors.

To say that the cause is anthropogenic, as claimed by the IPCC, is not scientifically correct, since there remain large uncertainties with natural contributions and the evidence for natural causes as having a significant, and dominant contribution to the late-20th Century warming is VERY high, as well as causing the warming over the last 100-150 years.


There are some large uncertainties in areas where there is little known impact by the various sources and there is minor uncertainty in areas where the impact is known to be more significant. But, to reach your conclusion you must ignore most of the data available and seek out the most reported uncertainty possible.

The focus only on the perception of uncertainty is not scientific at all, but more like the the pseudo science of the blogosphere and lobby groups.

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PostPosted: Sun May 27, 2012 5:39 am 
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Snowy123 wrote:
Wayne Stollings wrote:
...

Well that's because there is no such consensus on the subject. 8)


Of the GCR, definitely.

Quote:
Yes there are many who disagree with these findings, just as there are many who support the hypothesis.

The debate is not over by any means.

There is no "fingerprint" of GHG warming, since there are other factors that can explain such "fingerprints" for GHG warming.


No, there can always be straws to grasp to make such a claim, but the probability comparison is where the wheat is separated from the chaff.

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