Scientists: No link cloud coverage and global warming

May 11, 2009
sky, sun

With the U.S. Congress beginning to consider regulations on greenhouse gases, a troubling hypothesis about how the sun may impact global warming is finally laid to rest.

Carnegie Mellon University's Peter Adams along with Jeff Pierce from Dalhousie University in Halifax, Canada, have developed a model to test a controversial that says changes in the sun are causing .

The hypothesis they tested was that increased reduces cloudiness by changing cosmic rays. So, when clouds decrease, more sunlight is let in, causing the earth to warm. Some climate change skeptics have tried to use this hypothesis to suggest that may not be the global warming culprits that most scientists agree they are.

In research published in , and highlighted in the May 1 edition of Science Magazine, Adams and Pierce report the first atmospheric simulations of changes in atmospheric ions and particle formation resulting from variations in the sun and . They find that changes in the concentration of particles that affect clouds are 100 times too small to affect the climate.

"Until now, proponents of this hypothesis could assert that the sun may be causing global warming because no one had a computer model to really test the claims," said Adams, a professor of civil and environmental engineering at Carnegie Mellon.

"The basic problem with the hypothesis is that solar variations probably change new particle formation rates by less than 30 percent in the atmosphere. Also, these particles are extremely small and need to grow before they can affect clouds. Most do not survive to do so," Adams said.

Despite remaining questions, Adams and Pierce feel confident that this hypothesis should be laid to rest. "No computer simulation of something as complex as the atmosphere will ever be perfect," Adams said. "Proponents of the cosmic ray hypothesis will probably try to question these results, but the effect is so weak in our model that it is hard for us to see this basic result changing."

Source: Carnegie Mellon University (news : web)

Explore further: NASA balloons begin flying in Antarctica for 2014 campaign

add to favorites email to friend print save as pdf

Related Stories

Climate change -- research suggests it is not a swindle

Apr 03, 2008

New research has dealt a blow to the skeptics who argue that climate change is all due to cosmic rays rather than to man-made greenhouse gases. The new evidence shows no reliable connection between the cosmic ray intensity ...

Cosmic raise in cloud

Jan 19, 2006

New evidence that events in outer space affect the weather and climate of Earth has been revealed in a study by meteorologists at the University of Reading published in the Proceedings of the Royal Society on Wednesday 18 Jan ...

Researchers study harmful particulates

Feb 26, 2007

Reducing barnyard emissions is one way to help reduce the harmful effects of tiny atmospheric air particles that can cause severe asthma in children, and lung cancer and heart attacks in some adults.

Evidence shaky for Sun's major role in past climate changes

Sep 30, 2004

Computer models of Earth's climate have consistently linked long-term, high-magnitude variations in solar output to past climate changes. Now a closer look at earlier studies of the Sun casts doubt on evidence of such cycles of brightness, their inten ...

Recommended for you

Scientists make strides in tsunami warning since 2004

Dec 19, 2014

The 2004 tsunami led to greater global cooperation and improved techniques for detecting waves that could reach faraway shores, even though scientists still cannot predict when an earthquake will strike.

Trade winds ventilate the tropical oceans

Dec 19, 2014

Long-term observations indicate that the oxygen minimum zones in the tropical oceans have expanded in recent decades. The reason is still unknown. Now scientists at the GEOMAR Helmholtz Centre for Ocean Research ...

User comments : 35

Adjust slider to filter visible comments by rank

Display comments: newest first

omatumr
2.8 / 5 (16) May 11, 2009
A MODEL TO TEST HYPOTHESES??

Peter Adams and Jeff Pierce "have developed a model to test a controversial hypothesis that says changes in the sun are causing global warming."

What's wrong with the classical method of using experimental data to test any hypothesis?

The results are summarized in a recent paper, "Earth's Heat Source - The Sun," Energy & Environment 20 (2009) 131-144:

http://arxiv.org/abs/0905.0704

With kind regards,
Oliver K. Manuel
http://www.omatumr.com
dbren
3.6 / 5 (14) May 11, 2009
The headline says "No link cloud coverage and global warming". One of the researchers is quoted as saying "Until now, proponents of this hypothesis could assert that the sun may be causing global warming because no one had a computer model to really test the claims..." But this study only seems to address how solar activity affects cloud formation. So which is it? Have they determined conclusively that the sun does not contribute to global warming, or only that the sun does not have a large effect on cloud formation? I guess these questions make me one of the "Proponents of the cosmic ray hypothesis...", and up until now I never knew I was!
undrgrndgirl
3.2 / 5 (16) May 11, 2009
so...how do they explain the warming that is ALSO happening to our global neighbors?
Gammakozy
3.4 / 5 (15) May 11, 2009
Wow!!! So, by extension, the sun has no influence on earth's temperature. Then what keeps us warm? Must be the steady barrage of hot air forced upon us by those who have bought into the pseudo scientific cult of of man-made global warming.
deatopmg
2.6 / 5 (18) May 11, 2009
garbage in/garbage out. Nothing has been put to rest! Science is evidence based, not computer models.
mikiwud
2.1 / 5 (17) May 11, 2009
The pigs in the trough are really starting to squeal! If it's in print it adds to the propaganda, no matter how tenuous it is.
vos
3.5 / 5 (11) May 11, 2009
ohh I like that "controversial hypothesis" that the sun has anything to do with gorebull warming.
mjporter
2.3 / 5 (7) May 11, 2009
A MODEL TO TEST HYPOTHESES??







Peter Adams and Jeff Pierce "have developed a model to test a controversial hypothesis that says changes in the sun are causing global warming."







What's wrong with the classical method of using experimental data to test any hypothesis?



This paper you linked seems to have an entirely different focus. It does not make arguments one way or another as to whether the sun is a major player in global warming; it simply shows that the simple models used to conclude that the sun has no major effect with regards to global warming are grossly inadaquate and that concluding from them that the sun can be ignored is folly.



The hypothesis HERE is that changes in solar activity drastically affect cloud formation, and lower cloud formation in turn means that more sun reaches the earth (or rather, the surface), causing it to heat. Something of a silly hypothesis in the first place, if you ask me, but there you go. Whether solar activity has an affect on global warming in other ways is outside the scope of their study.



Also, while I'm leery of basing an entire study on nothing but computer models, doing anything else in cases like this would be difficult. Can't exactly mess around with the output of the sun at will to test and re-test its effect on cloud formation now, can we? ;)



daqman
3.1 / 5 (8) May 11, 2009
so...how do they explain the warming that is ALSO happening to our global neighbors?

What Canada and Mexico?
jonnyboy
3.3 / 5 (12) May 11, 2009
The only surprise here is that NATURE didn't publish their so-called "study"
Velanarris
4.1 / 5 (9) May 11, 2009
So 30% isn't a significant change in cloud particle formation? Well, 0.0003% is a significant percent of CO2 emissions.

There's something way out of proportion here.
Fazer
3.9 / 5 (11) May 11, 2009
I'm with you, Velanarris. Maybe we are mathematically dislexic? Small is large and large is small, and the ones that mother gives you, don't do anything at all...go ask Alice.
frogz
4.1 / 5 (9) May 11, 2009
This article has more holes in it than sun spots in the last decade.
lengould100
2.1 / 5 (7) May 12, 2009
Kiddies, go on back to school now before your teachers miss you.
djp
4.5 / 5 (8) May 12, 2009
Oh my, Sad to see "scientists" resorting to simulation and modeling as a proof.

At best, modeling and simulation based on 'preconceived mathematical formulas' is simply supplemental data. It can never take the place of physical observation and long term correlative data from geological samples and SOHO data.

If the claim isn't what the title says, then people should learn to carefully title their research.

There is extensive historical and satellite data to conclusively say that the sun's variance in specific spectral frequency output combined with extra-solar conditions has a significant impact on Earth's climate and the rate of that climate change.

Modeling ... pphhhaa
Velanarris
4.4 / 5 (7) May 12, 2009
Kiddies, go on back to school now before your teachers miss you.


Argumentum ad hominem or semper humorous failorum?
fleem
4.7 / 5 (6) May 12, 2009
So the headline "Scientists: No link cloud coverage and global warming" actually refers to "The hypothesis they tested was that increased solar activity reduces cloudiness by changing cosmic rays"

The vast majority of proponents of solar-induced global-warming are NOT claiming it is related to cosmic rays, since the cosmic ray energy is so miniscule compared to the recent change in total solar output.

Next we'll be seeing that exact same headline on an article that is actually about "The hypothesis that giant space potatoes are causing global warming"

Ah well, not to worry, since every soul that ever sees a headline always studies the entire article in depth--we can rest assured that no one will be mislead by that headline, thank goodness.
GrayMouser
3.4 / 5 (5) May 12, 2009
Oh my, Sad to see "scientists" resorting to simulation and modeling as a proof.

It's "cheaper", "faster", and the hardware is MUCH sexier.
jonnyboy
2.6 / 5 (5) May 12, 2009
Kiddies, go on back to school now before your teachers miss you.




Argumentum ad hominem or semper humorous failorum?



semper humorous failorum for sure
GrayMouser
2.6 / 5 (5) May 13, 2009
The vast majority of proponents of solar-induced global-warming are NOT claiming it is related to cosmic rays, since the cosmic ray energy is so miniscule compared to the recent change in total solar output.

The solar induced proponents for this particular theory is, put simply, that the reduction in the solar wind allows more cosmic rays to hit the atmosphere. Cosmic rays have been long known to cause cloud formation (the original cloud-chamber-in-the-large) so more cosmic rays should equal more clouds. By coincidence, more clouds equals a greater albedo for the Earth leading to cooler surface temperatures. The cosmic rays do not, in and of themselves, directly heat the atmosphere or surface.
Damon_Hastings
2 / 5 (2) May 14, 2009
so...how do they explain the warming that is ALSO happening to our global neighbors?

Are you referring to the recent warming of Mars? That was caused by a global sandstorm on Mars. Mars has a warming/cooling cycle caused by such sandstorms. We don't have those here. Mars is a completely different system, with completely different rules.
Damon_Hastings
1 / 5 (1) May 14, 2009
There is extensive historical and satellite data to conclusively say that the sun's variance in specific spectral frequency output combined with extra-solar conditions has a significant impact on Earth's climate and the rate of that climate change.

First I've heard of it. Can you provide a link? Or are you talking about temperature increases that occur gradually over many thousands of years?
Oh my, Sad to see "scientists" resorting to simulation and modeling as a proof.

Er... actually, simulation and models are commonly used in all fields of science. Typically they are used in situations where direct experimentation is not possible. For example, in this case, we are unable to adjust the energy output of the sun. We have a limited ability to study the past using geologic records and such, but current conditions are unprecedented in the history of the Earth, and so examining the past is of limited use in predicting the future.
GrayMouser
2.3 / 5 (3) May 14, 2009
There is extensive historical and satellite data to conclusively say that the sun's variance in specific spectral frequency output combined with extra-solar conditions has a significant impact on Earth's climate and the rate of that climate change.


First I've heard of it. Can you provide a link? Or are you talking about temperature increases that occur gradually over many thousands of years?

The speculation has been going on for years and, from other recent studies, abrupt climate change is not unusual.
http://icecap.us/...YCLE.pdf
http://icecap.us/...mate.pdf
http://www.physor...888.html
http://www.physor...313.html


Oh my, Sad to see "scientists" resorting to simulation and modeling as a proof.


Er... actually, simulation and models are commonly used in all fields of science. Typically they are used in situations where direct experimentation is not possible. For example, in this case, we are unable to adjust the energy output of the sun. We have a limited ability to study the past using geologic records and such, but current conditions are unprecedented in the history of the Earth, and so examining the past is of limited use in predicting the future.

That is unfair. The models are only as good as your understanding of the subject. Poor understanding leads to trashy output. In the case of climate modeling even the IPCC averaged the output of multiple models that didn't agree with each other. What kind of science do you have when you need to average the output of multiple unproven models?
Damon_Hastings
3 / 5 (2) May 15, 2009
There is extensive historical and satellite data to conclusively say that the sun's variance in specific spectral frequency output combined with extra-solar conditions has a significant impact on Earth's climate and the rate of that climate change.

First I've heard of it. Can you provide a link? Or are you talking about temperature increases that occur gradually over many thousands of years?

The speculation has been going on for years and, from other recent studies, abrupt climate change is not unusual.
http://icecap.us/...YCLE.pdf
http://icecap.us/...mate.pdf
http://www.physor...888.html
http://www.physor...313.html

ICECAP is an advocacy group well known for leading the charge in "debunking" the global warming "myth". It would be like me using Al Gore's website to back up my statements. So I won't respond on those.

Both of your physorg articles are discussing abrupt *regional* climate changes. Regional changes are nothing more than the transfer of energy from one part of the planet to another, kind of like a shell game. Global climate change is a whole different game, wherein you don't get to "cheat" by sweeping energy under the rug. Thus, it tends to happen much more slowly. Also, when geologists talk about "abrupt" climate change, they might mean "abrupt" on geological time scales. Neither of these articles gives actual numbers, so these guys could be talking about changes of 1 degree per thousand years, for all we know. Finally, neither article discusses solar variation, so neither relates to your original point. The first article is talking about ocean currents shutting down (which has not happened in recent history and thus is not relevant to recent warming.) The second article discusses the comings and goings of droughts in small regions.

In the case of climate modeling even the IPCC averaged the output of multiple models that didn't agree with each other.

The question is not whether two given models agree (they never will), but by how much they disagree. And is that disagreement enough to overwhelm the general trends produced by both models?
Velanarris
4 / 5 (3) May 15, 2009
And is that disagreement enough to overwhelm the general trends produced by both models?
Absolutely. If neither model agrees to within a certain degree based on scale then neither model can be considered accurate for even somethign as basic as trending.

Especially when most of the utilized models completely erase well known warm periods when viewed recursively.
Damon_Hastings
2.7 / 5 (3) May 15, 2009
If neither model agrees to within a certain degree based on scale then neither model can be considered accurate for even somethign as basic as trending.

"Certain degree" is subjective. The IPCC report did mention the inconsistencies (mostly minor, though a few major) between some models, and this is largely why their confidence figure is at 80% to 90% rather than 100%. You would take the same data and put the confidence much lower. So, clearly, their subjective view of that "certain degree" you mention differs from your view. And since this is a subjective disagreement, I'm certainly not qualified to make the call. I think we'll just have to agree to disagree. ;-)
Velanarris
4 / 5 (3) May 15, 2009
"Certain degree" is subjective.
Not when speaking in generalities about a trend analysis. A trend is going to be in one direction, to one degree. The only refinement here is if raw data inaccuracies are present due to the degree of precision in measurement, not based on how the observer felt that day. The latter would be considered "human error" making measurements invalid, not "less but still valid".

The IPCC report did mention the inconsistencies (mostly minor, though a few major) between some models, and this is largely why their confidence figure is at 80% to 90% rather than 100%.
How exactly does one determine a percent of confidence. You can be confident or not confident, I don't see an inbetween as less than 100% confident means not confident.

You would take the same data and put the confidence much lower. So, clearly, their subjective view of that "certain degree" you mention differs from your view.
But that's the point, observations of a process are not subjective and scientific, they're either subjective or scientific. Science deals with objective observation, subjective observation is why Newtonian dynamics are a great approximation, but are not accurate to the nth degree.
GrayMouser
3 / 5 (2) May 16, 2009
"Certain degree" is subjective. The IPCC report did mention the inconsistencies (mostly minor, though a few major) between some models, and this is largely why their confidence figure is at 80% to 90% rather than 100%.

Minor inconsistencies? None of the models agree with each other even within 80%.
None of the models predicted the current cooling period even when the CO2 levels were increasing.
None of the models have predicted the global or local climate even 5 years in the future.
GemRuinsKeeper
not rated yet May 17, 2009
So 30% isn't a significant change in cloud particle formation? Well, 0.0003% is a significant percent of CO2 emissions.



There's something way out of proportion here.


Epic win!
GemRuinsKeeper
5 / 5 (1) May 17, 2009
PS: I think, while I agree that human influence on the global environment is overhyped, it really isn't all that relevant towards whether or not humans should be punished for having a larger carbon footprint. The fact is humans affect the environment in everything they do, especially when they are successful. Why is this grounds for punishment?

Being able to predict global climate trends is important and should be made by a well informed, non-politically driven community of scientists, which we could have but don't thanks to government grants which are driven out of the desire to justify more government control rather than search for truth. Said search for truth can only occur when free of conflict of interests, and when the truth is what makes or breaks the scientist.

It may very well be that we are facing a crisis, but isn't a crisis also an opportunity? We could be creating self sustaining locally controlled environmental enclosures, turning scientific speculation into reality. Instead, we are all busy debating whether or not it is going to happen. Now we don't know what is going to happen, but we should still be prepared.

I think these "SSLCEE"s, or "slice"s, are a great idea, and all we need is a motivation. So I say, bring on the global catastrophe! Humanity will overcome their dependence on the global environment, just as long as there are still people who strongly believe we have a right to exist and have the power to act on that belief!
jeffsaunders
not rated yet May 17, 2009
The title and the article seem to have very little in common. I expect that we will see the title appear a lot more often than the actual content of this article conclude.

Never heard the argument that cosmic rays were causing global heating so it was news to me that many people were putting that forward as an alternative argument to man made global warming.

Now that I have been informed that cosmic rays mat have been causing global warming I cannot see how they could have been doing it. Causing increase cloud cover would lead to global cooling and since the article states that cosmic rays actually contribute to cloud cover then it would mean that an increase in cosmic rays would lead to an increase in cloud cover and hence global cooling.

Since the study limited itself to one minor aspect of the suns contribution to the global climate it strikes me that the heading is so far off base that it is from some other planet.

At least the authors of the study should have considered that an increase of solar radiation would contain more output than just a few cosmic rays that may contribute marginally to cloud cover. We also get an increase in pure energy and I am sure that would have a warming effect. Otherwise Mercury would not be hotter than Pluto.
GaryB
not rated yet May 17, 2009
Wow!!! So, by extension, the sun has no influence on earth's temperature. ...


If you can't read, don't debate. There is NO such extension to what the authors say. They simply say the cosmic ray influence on cloud formation is not supported by their models.

As for those who believe in "experiments" rather than models ... beyond are simple senses, which are often misleading, we can observe nothing except through our models. Causality is always omplex -- even if you had time to observe cosmic rays through many solar cycles, you still wouldn't know what causes what since statistics can only show correlation, not causation. Causation can be shown via experimentation (run earth twice, with and without industrialization ... somewhat impractical). But, we can posit and test models and that is mostly the core of science.
MatthiasF
5 / 5 (2) May 17, 2009

As for those who believe in "experiments" rather than models ... beyond are simple senses, which are often misleading, we can observe nothing except through our models. Causality is always omplex -- even if you had time to observe cosmic rays through many solar cycles, you still wouldn't know what causes what since statistics can only show correlation, not causation. Causation can be shown via experimentation (run earth twice, with and without industrialization ... somewhat impractical). But, we can posit and test models and that is mostly the core of science.


A computer model is not an experiment. It's just a fancy animation generated by complex filters designed by scientists wanting specific results. On top of that it's not reproducible like an experiment, which means it's impossible to provide a single-blind situation which is the basis for ALL SCIENTIFIC PROOF.
fcnotpdaaj
1 / 5 (2) May 17, 2009
Please people, yes this study is a joke! This article name is a joke, and people who believe in Gobal warming are a joke. Liberals and the Gobal Warming cult as www.democratsareajoke.com keeps saying and you can see even in this article love to play (ok lie) with words.
GrayMouser
1 / 5 (2) May 20, 2009
As for those who believe in "experiments" rather than models ... beyond are simple senses, which are often misleading, we can observe nothing except through our models. Causality is always omplex -- even if you had time to observe cosmic rays through many solar cycles, you still wouldn't know what causes what since statistics can only show correlation, not causation. Causation can be shown via experimentation (run earth twice, with and without industrialization ... somewhat impractical). But, we can posit and test models and that is mostly the core of science.


A computer model is not an experiment. It's just a fancy animation generated by complex filters designed by scientists wanting specific results. On top of that it's not reproducible like an experiment, which means it's impossible to provide a single-blind situation which is the basis for ALL SCIENTIFIC PROOF.

A model of a theory, in the hands of a honest researcher, can point to areas that need greater exploration. They don't provide proof of anything but mathematical equations. And even that could be questioned given a lack of understanding of the representation of continuous (linear) data changes in a system that is not capable of representing it, ie floating point numbers.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.