sunspot theory of global warming

[Paradelver]

I don't know if this has been mentioned, but I believe this may be one of the best sites of good information and summary reviews of climate change issues available: http://www.metoffice.gov.uk/research/hadleycentre/

 

So what is causing the observed ice melts on Mars and the moons of Saturn and Jupiter?

 

Consider the distance equation for planetary heating, which I have seen requiring the earth to rise anywhere from 86 degs to 3,100 deg. Celsius to account for solar heating of Jupiter and Pluto (another claim apparently). Somehow I doubt this theory.

[swansont]

So what is causing the observed ice melts on Mars and the moons of Saturn and Jupiter?

 

Observed by whom? (i.e. do you have citations for this?)

 

As far as Mars goes, I recall reading the albedo of Mars has changed.

 

This wasn't what I read, but was the first thing I found in Googling(pdf file)

http://humbabe.arc.nasa.gov/~fenton/pdf/fenton/nature05718.pdf

[jryan]

Consider the distance equation for planetary heating, which I have seen requiring the earth to rise anywhere from 86 degs to 3,100 deg. Celsius to account for solar heating of Jupiter and Pluto (another claim apparently). Somehow I doubt this theory.

 

So it is a coincidence thatwe see heating on all of these planets and moons at the same time? Is there a theory for why the melting is happening otherwise? Or is this one of those points of interest we are just not supposed to ask about?

[swansont]

So it is a coincidence thatwe see heating on all of these planets and moons at the same time? Is there a theory for why the melting is happening otherwise? Or is this one of those points of interest we are just not supposed to ask about?

 

Ask away. I've provided one reference. But the numbers Paradelver gives (do you have a source?) eliminate solar variation as the cause. Jupiter, Saturn, et. al, only get a few percent of the solar flux we get (which one can calculate purely from geometry)

[SkepticLance]

Swansont

 

That argument is fallacious, since it is not ice that is melting on the moons of Saturn. The average temperature is way below zero, and it would take enormous amounts of heat to melt ice.

 

Instead, it is probably a material (like methane) that is normally a gas on Earth that is melting. If the temperature is only a little colder than that needed to convert the methane to solid form, then a slight increase in solar flux will be enough.

 

On Mars, telescopic observation has shown a slight shrinkage of polar 'ice' caps. Of course, it is not ice that is melting. It is solid CO2 turning to gas.

 

Anyway, while the sun is definitely warming, as shown by satellite studies, the amount is very slight, and definitely not enough to account for global warming on Earth. So you need not feel that your favourite theory is threatened.

[swansont]

Swansont

 

That argument is fallacious, since it is not ice that is melting on the moons of Saturn. The average temperature is way below zero, and it would take enormous amounts of heat to melt ice.

 

Instead, it is probably a material (like methane) that is normally a gas on Earth that is melting. If the temperature is only a little colder than that needed to convert the methane to solid form, then a slight increase in solar flux will be enough.

 

Please note that I have asked for references from both individuals so that this can be checked. I'll ask you, too, since your scenario also would need to be checked.

 

Please also note that I never mentioned anything about what was melting on Saturn. The only one to mention melting was jryan. Paradelver mentioned heating of Jupiter, not melting. Without a source (again, which I asked for) how can you conclude that the argument is fallacious?

 

On Mars, telescopic observation has shown a slight shrinkage of polar 'ice' caps. Of course, it is not ice that is melting. It is solid CO2 turning to gas.

 

Anyway, while the sun is definitely warming, as shown by satellite studies, the amount is very slight, and definitely not enough to account for global warming on Earth. So you need not feel that your favourite theory is threatened.

 

Nothing here contradicts what I said.

[JohnB]

Swansont, I think they may be referring to this article in National Geographic. If you google his name you'll find him praised and castigated all over the place.

 

While Habibullo Abdussamatov is head of the St. Petersburg's Pulkovo Astronomical Observatory in Russia the only thing I can seem to find by him is here. The article itself appears to be from an interview. I would suggest that the pertinent part of his "paper" might be;

 

Summarizing, observed cyclicities in solar variations are determined by corresponding quasi-periodic changes in both activity and size (and, therefore, total irradiance). That is why, one can expect that in the nearest future (in accordance with expected decay of the activity and irradiance secular cycle) regular secular decrease of the Earth temperature

should replace the contemporary not anomalous but regular secular global warming.

 

Who knows, he might be right. Have you seen the latest "Top 10" from the Hadley Centre Met Office? Rearrange them in chronological order and note the "Difference from average with respect to 1961-90". Interesting, no?

[SkepticLance]

bascule said :

 

"You've seemed to skip directly from the sunspot cycle to an assumed impact upon solar irradiance and thus global climate change without understanding solar irradiance. SkepticLance has done the same. Implying the former has an effect on global climate change without understanding the latter is nothing but a post hoc ergo propter hoc fallacy."

 

And you have fallen into the fallacy of assuming a simplistic mechanism. As I have said before, many times, sunspot activity can influence the Earth in several ways other than via electro-magnetic radiation (solar irradiance). Sunspot activity has major magnetic effects, and causes substantial changes to the solar wind. It is very well established that cosmic ray influx to the Earth drops substantially when sunspot activity is high, and this is due to non electromagnetic radiation effect. Solar flares are more likely at such times, and the polar auroras are more active also. None of these are due to changes in radiance.

 

There are several hypotheses as to how sunspot activity affects global climate. Since we do not know the mechanism, how can we calculate the effect?

 

To search for an empirical correlation between sunspot activity and global temperature change is a perfectly valid piece of research. I doubt that sunspot number per se is the best approach, since sunspot activity depends on the number of sunspots, plus size of sunspots, plus intensity of activity within each sunspot. However, sunspot number may still correlate loosely with total sunspot activity, and I would be interested to see the results when graphs are complete.

 

For those who might be interested, and hopefully have an open mind, read :

 

http://www.environmental-expert.com/resultEachPressRelease.aspx?cid=20909&codi=20225&level=1&idproducttype=8

[bascule]

And you have fallen into the fallacy of assuming a simplistic mechanism. As I have said before, many times, sunspot activity can influence the Earth in several ways other than via electro-magnetic radiation (solar irradiance).

 

Really? Do tell!

 

Sunspot activity has major magnetic effects

 

Hmm, and you don't categorize that under EM... why?

 

and causes substantial changes to the solar wind. It is very well established that cosmic ray influx to the Earth drops substantially when sunspot activity is high, and this is due to non electromagnetic radiation effect.

 

Interesting. I'd like to know more about how solar wind affects the climate system, but my initial research shows that solar wind affects high frequency variations in solar radiation, and because oceans possess a large thermal inertia they damp out such high-frequency variations, to the point that the observable effects of solar wind are likely to be confined to time scales of centuries.

 

Solar flares are more likely at such times, and the polar auroras are more active also. None of these are due to changes in radiance.

 

There are several hypotheses as to how sunspot activity affects global climate. Since we do not know the mechanism, how can we calculate the effect?

 

I'd like to first know why you think that the types of solar activity you describe don't cause changes in solar radiation. I'd also like to know what sort of effects you think solar activity has on the earth's climate system that isn't directly attributable to solar radiation.

 

To search for an empirical correlation between sunspot activity and global temperature change is a perfectly valid piece of research.

 

Sure, but you seem to downplay solar radiation as the causal link between sunspot activity and the Earth's climate system. Why exactly is that? By what non-electromagnetic force do you see solar activity having a significant impact on Earth's climate system?

[SkepticLance]

To bascule

 

To try to answer your queries.

 

I do not classify sunspot magnetism as electro-magnetic radiation, because it aint. Sure, there is a relationship, but magnetism is not EMR.

 

 

You said :

 

"but my initial research shows that solar wind affects high frequency variations in solar radiation, "

 

I did not say the solar wind warmed the Earth. I just listed it as one non EMR result of sunspot activity. As I said, we do not actually know the mechanism, though theories exist.

 

"I'd like to first know why you think that the types of solar activity you describe don't cause changes in solar radiation."

 

In fact, it does cause changes in solar radiation. It is just that those changes are very small - only able to induce a warming of about 0.01 to 0.02 C. Since this is clearly insufficient to cause the warming observed, we look for an alternative mechanism.

 

That is why I downplay the solar radiation effect. There is one theory based on the fact that the biggest increase in radiation during times of high sunspot activity is ultra violet. This theory says that more UV means more ozone which means more greenhouse effect. However, there are other theories also. The main alternative theory is based on the fact that high sunspot magnetic fields deflect cosmic rays away from the Earth. This has been demonstrated to be true by direct measurement. Perhaps there are several mechanisms.

[swansont]

note: posts moved from "Objective global warming" thread to this one to try and stay on topic for the various threads. Here you can discuss sunspot mechanism hypotheses or lack thereof.

[iNow]

To bascule

 

To try to answer your queries.

 

I do not classify sunspot magnetism as electro-magnetic radiation, because it aint. Sure, there is a relationship, but magnetism is not EMR.

 

 

You said :

 

"but my initial research shows that solar wind affects high frequency variations in solar radiation, "

 

I did not say the solar wind warmed the Earth. I just listed it as one non EMR result of sunspot activity. As I said, we do not actually know the mechanism, though theories exist.

 

"I'd like to first know why you think that the types of solar activity you describe don't cause changes in solar radiation."

 

In fact, it does cause changes in solar radiation. It is just that those changes are very small - only able to induce a warming of about 0.01 to 0.02 C. Since this is clearly insufficient to cause the warming observed, we look for an alternative mechanism.

 

That is why I downplay the solar radiation effect. There is one theory based on the fact that the biggest increase in radiation during times of high sunspot activity is ultra violet. This theory says that more UV means more ozone which means more greenhouse effect. However, there are other theories also. The main alternative theory is based on the fact that high sunspot magnetic fields deflect cosmic rays away from the Earth. This has been demonstrated to be true by direct measurement. Perhaps there are several mechanisms.

 

What are the specific sources which support your assertions? And please, don't make me ask six times, nor tell me that any idiot can google, and also no wikipedia.

[SkepticLance]

To iNow

 

A lot of this is discussed in the reference I put up in post 33. I know. You didn't read it.

[swansont]

I'll venture a guess that a press release isn't what iNow had in mind when asking for a "specific source"

[SkepticLance]

swansont

 

Your opinion I respect. However, iNow has been sniping at me in more than one thread, for no reason at all except for the desire to attack me. Damned if I am going to waste my time searching new sources because he wants me to. The source I quoted may not be a peer reviewed paper, but it agrees with a whole lot of other stuff I have read. If iNow does not accept that, tough.

[iNow]

swansont

 

Your opinion I respect. However, iNow has been sniping at me in more than one thread, for no reason at all except for the desire to attack me. Damned if I am going to waste my time searching new sources because he wants me to. The source I quoted may not be a peer reviewed paper, but it agrees with a whole lot of other stuff I have read. If iNow does not accept that, tough.

 

Not quite the answer I was hoping for. I'm not sure why it's so hard to find a source if your assertions are valid. You can accuse me of sniping all you want. My request was simple. Do you have a source to support your assertions?

 

 

I have no desire to attack you. What I attack is unsupported assertions and false representations.

 

 

 

From YOUR article:

 

In 1970, Russian researchers using high-altitude balloons to measure sunlight reported a 2 percent rise in the sun's output as the sun moved from periods of little sunspot activity to peak activity. Today, using better measurements from satellites over the past 28 years, the change in total solar irradiance is estimated to be much smaller, between 0.05 percent and 0.07 percent. The most important component for climate-change purposes - visible light - represents about half of this change, says Tom Woods, a researcher at the University of Colorado's Laboratory for Space and Atmospheric Physics, based in Boulder.

 

Other studies suggest that changes in sunlight - as well as the cooling effect of volcanic activity, which sends sunlight-reflecting particles high in the sky - probably played a major role in climate during preindustrial times and even into the early 20th century. But even these find that CO2 emissions have dominated the scene over the past half century.

 

One candidate is UV light. During swings in sunspot cycles, the largest fractional changes in the sun's output occur in the ultraviolet range, Shindell notes. But much of that is absorbed by ozone in the stratosphere - which may be the connection, he suggests. The rise and fall of UV light can alter the amount of heat-trapping ozone in the stratosphere, changing its circulation patterns. These changes can work their way into the layer below, the troposphere, where weather and people meet. Instead of warming the troposphere, changes in solar UV output appear to redistribute warmth, chill, rainfall, and other conditions already present.

 

 

 

I don't see anything supporting your comments:

 

I'd like to first know why you think that the types of solar activity you describe don't cause changes in solar radiation.

 

In fact, it does cause changes in solar radiation. It is just that those changes are very small - only able to induce a warming of about 0.01 to 0.02 C. Since this is clearly insufficient to cause the warming observed, we look for an alternative mechanism.

 

<...>

 

There is one theory based on the fact that the biggest increase in radiation during times of high sunspot activity is ultra violet. This theory says that more UV means more ozone which means more greenhouse effect. However, there are other theories also. The main alternative theory is based on the fact that high sunspot magnetic fields deflect cosmic rays away from the Earth. This has been demonstrated to be true by direct measurement.

 

 

I was of the impression that it was the Earth's magnetic field which deflected "cosmic rays" away from the Earth, not the Sun's... but hey... maybe you'll provide a source so I can educate myself on the topic?

[swansont]

swansont

 

Your opinion I respect. However, iNow has been sniping at me in more than one thread, for no reason at all except for the desire to attack me. Damned if I am going to waste my time searching new sources because he wants me to. The source I quoted may not be a peer reviewed paper, but it agrees with a whole lot of other stuff I have read. If iNow does not accept that, tough.

 

 

I'm hesitant to assign a motive to anyone that is other than a simple desire to see supporting evidence, and in discussions like this, that's not an unreasonable thing to do.

 

As I recall, the most prominent evidence you have given for sunspot activity causing warming prior to the last several decades was a graph from Solanki, et. al that has two main problems: 1) it a was a total solar irradiance reconstruction, i.e. they were looking at the output energy, which you agree above is not the cause of much warming, and 2) it's been rendered moot by the author coming out with a more recent paper with different (and presumably better) results.

 

So it's a perfectly reasonable thing to ask why you are still advancing this hypothesis, because surely you must have other evidence to support the position. Or, if I'm mistaken about this, and there was other support given, please refresh my memory.

[SkepticLance]

To swansont

 

The reason I am reluctant to spend the time searching for more references is just that it is iNow asking. He has a recent history of trying to be destructive towards any post I put up, rather than actually searching for the truth. However, since you ask .....

 

There are heaps of references covering the main points I have shown.

 

eg.

http://news.bbc.co.uk/2/hi/science/nature/3869753.stm

 

This one mentions Dr. Solanki. I know he has made errors relating to recent events, but his work overall cannot be dismissed because of that.

 

Sunspot activity was high during the Medieval Climate Optimum and almost non existent during the Little Ice Age. Sunspots loosely correlated with warming/cooling from 1880 to 1940. Sunspots have been relatively constant for the past 50 odd years, apart from the 11 and 22 year cycles, and warming since 1976 is correctly ascribed to greenhouse gases.

 

Below is an article from Woods Hole, which ascribes past climate changes to both the sun (sunspots as measured by radio-isotopes in sediment) and to oceanic effects.

 

http://www.whoi.edu/oceanus/viewArticle.do?id=18371

 

I quote :

 

"Radiocarbon is generated by cosmic rays that penetrate Earth’s upper atmosphere. When the sun is more magnetically active, more sunspots spew more radiation; that blocks cosmic rays from reaching our celestial neighborhood, and less radiocarbon is produced. When the sun is less active, fewer cosmic rays are blocked, and more radiocarbon is created"

 

Also

 

"We were trying to correlate the timing of abrupt shifts seen in the Cariaco marine records with climate shifts on land that were detected by other researchers using 10Be in ice cores and 14C in tree rings. We got a near-perfect match of events.

 

The problem is that the fit was too good. The marine and terrestrial records of radiocarbon should not be a one-to-one match. Because the oceans draw down a portion of dissolved radiocarbon into the depths, there should be less radiocarbon in surface waters (and in fossil shells) than in the atmosphere."

 

The scientists of Woods Hole go on to describe how oceanic currents may have influenced the results also. The point is that, in these studies, solar effects (meaning sunspots - since they were measuring radiocarbon, which varies according to sunspot activity and its effect on cosmic rays) change ancient climates. The fact that ocean effects influenced their results does not alter that fact.

 

The relationship between sunspots and cosmic rays, and the tree ring records are discussed in :

http://www.abc.net.au/science/news/space/SpaceRepublish_1230571.htm

 

I also have a paper copy of an item in Science.

Science : Vol 294. 7 December 2001

"Persistent Solar Influence on North Atlantic Climate during the Holocene"

 

I cannot give you an internet reference to this, but the abstract says :

 

" Surface winds and surface ocean hydrography in the subpolar North Atlantic appear to have been influenced by variations in solar output through the entire Holocene. The evidence comes from a close correlation between inferring changes in production rates of the cosmogenic nuclides carbon-14 and beryllium-10 ......."

 

Since the radio-nuclides are a measure of sunspot activity, rather than direct EMR, due to the changes in cosmic rays, we can say that the Holocene changes correlate with sunspot changes.

[swansont]

To swansont

 

The reason I am reluctant to spend the time searching for more references is just that it is iNow asking. He has a recent history of trying to be destructive towards any post I put up, rather than actually searching for the truth. However, since you ask .....

 

There are heaps of references covering the main points I have shown.

 

eg.

http://news.bbc.co.uk/2/hi/science/nature/3869753.stm

 

This one mentions Dr. Solanki. I know he has made errors relating to recent events, but his work overall cannot be dismissed because of that.

 

No, I haven't dismissed the overall work, but this (and the third link mentioning Solanki) date from 2004, and are likely referencing the work that was published then, which is at odds with the later publication.

 

Sunspot activity was high during the Medieval Climate Optimum and almost non existent during the Little Ice Age. Sunspots loosely correlated with warming/cooling from 1880 to 1940. Sunspots have been relatively constant for the past 50 odd years, apart from the 11 and 22 year cycles, and warming since 1976 is correctly ascribed to greenhouse gases.

 

And I seem to recall being able to only find graphs of sunspot number, rather than overall activity. The sunspot number correlation was poor, because there were times when there were anti-correleations. This is the kind of data that it would be useful to see.

 

Below is an article from Woods Hole, which ascribes past climate changes to both the sun (sunspots as measured by radio-isotopes in sediment) and to oceanic effects.

 

http://www.whoi.edu/oceanus/viewArticle.do?id=18371

 

 

It seems that they have not yet made a determination — they are still testing their hypothesis.

 

"Such a scenario is speculative and highly controversial. We cannot build such a case from just one event in geologic time, so now we are trying to learn more from the rich data trove of Cariaco Basin sediments."

 

 

I also have a paper copy of an item in Science.

Science : Vol 294. 7 December 2001

"Persistent Solar Influence on North Atlantic Climate during the Holocene"

 

I cannot give you an internet reference to this, but the abstract says :

 

" Surface winds and surface ocean hydrography in the subpolar North Atlantic appear to have been influenced by variations in solar output through the entire Holocene. The evidence comes from a close correlation between inferring changes in production rates of the cosmogenic nuclides carbon-14 and beryllium-10 ......."

 

Since the radio-nuclides are a measure of sunspot activity, rather than direct EMR, due to the changes in cosmic rays, we can say that the Holocene changes correlate with sunspot changes.

 

 

EMR levels change with sunspot activity, too. That's what the TSI reconstructions do, AFAIK. How do you separate the two effects?

 

 

 

edit: and I assume that we're talking about pre-1950 effects, because cosmic ray cycles have been pretty steady as of late

http://ulysses.sr.unh.edu/NeutronMonitor/Misc/neutron2.html

[SkepticLance]

To swansont

 

Re the Woods Hole work. The hypothesis they are working on relates to oceanic effects, which you will see if you read the paper. The sunspot effect is not in the same situation.

 

You said :

 

"And I seem to recall being able to only find graphs of sunspot number, rather than overall activity. The sunspot number correlation was poor, because there were times when there were anti-correleations."

 

Correlations are not perfect (ie the C.C. is less than 1). However, that does not mean they are not there. The Maunder Minimum, which is at the coldest part of the Little Ice Age, had few or no sunspots at all. The fact that the coefficient is less than 1 is a reflection of the fact that more than one factor is at play. However, sunspot activity is one of the major factors.

 

"EMR levels change with sunspot activity, too. That's what the TSI reconstructions do, AFAIK. How do you separate the two effects?"

 

As I have already said, EMR effects are trivial. A warming or cooling of 0.1 C or more cannot be explained by EMR effects. We have to look at other mechanisms.

 

"edit: and I assume that we're talking about pre-1950 effects, because cosmic ray cycles have been pretty steady as of late"

 

As have sunspot cycles. A sunpot cycle aint gunna change cosmic ray flux unless the sunspot cycle changes. As I have agreed many times, climate change over the past 3 decades is due to greenhouse gases. The sunspot effect has been minimal.

[swansont]

Correlations are not perfect (ie the C.C. is less than 1). However, that does not mean they are not there. The Maunder Minimum, which is at the coldest part of the Little Ice Age, had few or no sunspots at all. The fact that the coefficient is less than 1 is a reflection of the fact that more than one factor is at play. However, sunspot activity is one of the major factors.

 

There's not perfect, and then there's nonexistant.

http://en.wikipedia.org/wiki/Image:Sunspot-temperature-10000yr.svg

 

Prior to ~5000 years there is strong anti-correlation. This is sunspot number, as I noted before. If you have sunspot activity data, feel free to present it.

[SkepticLance]

To swansont

 

According to your Wiki graph, there is a lack of correlation over the period 5000 to 10000 BP. I have no data to agree or disagree with that. However, from 5000 BP, your Wiki graph showed a very impressive correlation.

 

We agree that other factors are involved. Perhaps they are strong enough to overwhelm the sunspot effect before 5000 BP? After that time, the correlation is hard to deny.

 

We know that sunspot activity and temperature do not correlate over the past half century. That is because of other stronger factors. Why do you not think this applies 5000 to 10000 BP?

 

Anyway, a lack of correlation at that earlier time does not alter the reality of strong correlation in more recent millennia.

 

Incidentally, the Wiki article may have said that was sunspot number, but that cannot be true. Sunspot number data is only available back to the 17th century, when sunspots were viewed through telescopes and counted. Before that, radio-isotopes are used as a surrogate measure. The amount of these depends on cosmic rays, which diminish when sunspot activity is strong. Thus the wiki graph can only show an indirect estimate of sunspot activity.

 

Here is another reference that shows more recent sunspot/climate interaction.

 

http://academic.emporia.edu/aberjame/ice/lec20/lec20.htm

[iNow]

Anyway, a lack of correlation at that earlier time does not alter the reality of strong correlation in more recent millennia.

Can you name a single reason why sunspots would not be consistent in driving global temperature across epochs?

 

 

It's like you're saying, "That other part of the data completely defeats my assertion, so instead, let's just look at this nice slice that seems to support my claims."

[swansont]

According to your Wiki graph, there is a lack of correlation over the period 5000 to 10000 BP. I have no data to agree or disagree with that. However, from 5000 BP, your Wiki graph showed a very impressive correlation.

 

We agree that other factors are involved. Perhaps they are strong enough to overwhelm the sunspot effect before 5000 BP? After that time, the correlation is hard to deny.

 

We know that sunspot activity and temperature do not correlate over the past half century. That is because of other stronger factors. Why do you not think this applies 5000 to 10000 BP?

 

What is the evidence that it does? Why should I assume that there are confounding factors for half of the graph? And why should I assume that it's for the first half, and not the second half? The graph gives equal support to the notion that sunspot activity decreases temperature as it does for increasing it. The only reasonable conclusion from that graph is that there is no noticeable effect.

[SkepticLance]

I must admit the graph is a very interesting one. Swansont's suggestion that it all balances out to zero effect is quite ludicrous. There is a clear and obvious relationship - just needs a mechanism (or two) to explain.

 

The first part of the graph is the warming of the Younger Dryas period. This is the warming that led to our present day salubrious global temperatures. In other words - a very good thing! Before this warming, there was a sharp drop in temperature, which might have reflected the beginnings of a new glaciation period. The Younger Dryas warming was a dramatic and fortunate and rapid event, reflecting some fairly dramatic cause.

 

It is correlated with the beginnings of human agriculture. However, determining cause and effect is not currently possible - since we have not adequately dated the actual initial rise of agriculture. One theory is that the rise of agriculture precipitated a period of dramatic global warming. Another theory is that global warming permitted agriculture to occur. Cause and effect - which way around?

 

Anyway, I think we need to ignore the Younger Dryas warming in this discussion. It is a singular event, and was probably caused by a singular factor - not the normal warming/cooling cycles.

 

That leaves two sections of the graph which are quite intriguing. 9000BP to 5000BP sees a clear cut negative correlation with sunspot activity. 5000BP to (almost) the present sees a clear cut positive correlation.

 

We cannot deny the correlation. It is there and clear cut. I just do not know right now why sunspots should cause warming at one stage, and cooling at another. A puzzling conundrum.

 

Predictable that the detractors will try to deny the relationship. That denial is equivalent to AGW deniers refusing to accept the 30 year relationship between greenhouse gases and warming.

 

Some people will deny data to back up their theories.