Science Daily -- 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 hypothesis that says changes in the sun are causing global warming.
The hypothesis they tested was that increased solar activity 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 greenhouse gases may not be the global warming culprits that most scientists agree they are.
In research published in Geophysical Research Letters, and highlighted in the May 1 edition of Science, Adams and Pierce report the first atmospheric simulations of changes in atmospheric ions and particle formation resulting from variations in the sun and cosmic rays. 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."
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Comments: 24
People (except denialists, that is) usually provide links to such information.
Jack.
The IPCC Report did account for "solar forcing", which was considered to be a minor influence relative to ghg emissions. Solar forcing was ruled out some time ago.
Your link to science daily didn't reference said study.
But when you have global warmists who dismiss scientists with opposing views with comments like;
""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 research of the effects of sun on clouds is ongoing and this one model is not the end of the discussion as you suggest.
Hmmm.... lets see the earth's temperature has moderated for the last, what? 10 years? the Sun began a quiet phase about, what? 10 Years ago?
Cause and effect and all you know...we can't find all of that hidden heat....Well maybe this latest study answers it all...but probably not.
Here is a link to part of the article: Changes In The Sun Are Not Causing Global Warming
Jack
The fact that the planet's temperature has moderated in the last few years,
taking into consideration that the sun has quieted in the same time frame, indicates that the sun had a greater role in global warming in the past than the IPCC has given it credit.
Global warming is here and probably always will be here in the effects of cooling and warming but it does not mean we have to help it along at an accelerated pace and destroy our self when we can clean up the environment we have destroyed.
A man convinced against his will is of the same opinion still.
"Rajendra Pachauri, the head of the U.N. Panel that shared the 2007 Nobel Peace Prize with former U.S. Vice President Al Gore, said he would look into the apparent temperature plateau so far this century.
"One would really have to see on the basis of some analysis what this really represents," he told Reuters, adding "are there natural factors compensating?" for increases in greenhouse gases from human activities."
Jack,
Even the IPCC admits that warming of the planet has paused.
The problem with global warmists is that they don't believe in science....they believe in consensus and consensus is not science it is belief.
Scientists know that it only takes one fact to be proven wrong.
"Global Warming" is not a philosophy or a religion but an observed phenomenon.
Scientists (meteorologists, climatologists, etc.) endeavour to study the phenomenon and try to devise theories that explain the reason for the observed phenomenon.
As with most science, there is no definitive conclusion but rather there are working theories: these are theories that explain many of the observations and don't contradict any known facts. As you observed, one contradictory fact disproves a theory.
Since there are no definitive conclusions the consensus of opinions amongst accredited scientists tends to carry the day in any field of study. The consensus of opinions amongst the scientists who specialize in this field are as follows: the planet seems to be warming and most models project that warming will continue over time, with fluctuations up and down being normal but the trend rising; anthropogenic activity, particularly the burning of fossil fuels on a large scale globally by humans, seems to be a significant contributor to the phenomenon; models for the projected rise in temperatures over the coming century suggest some dire consequences to humans and other life forms in terms of desertification of land, increased incidence of drought and flooding, higher risk of forest fires, loss of habitat for some species and migration of species to expanded habitats that thereby threaten other species inhabiting those changing environmental niches, amongst others.
Those who hold beliefs or philosophies that reject the possibility of any human contribution to observed climactic changes are continually seeking a scientific explanation that will suppor their philosophy. This is a good example of backwards science: start with a conclusion and look for a theory that supports it. One of their currently preferred theories is that sun-spot activity, not human activity, is the cause. This study debunks that by providing observations that contradict the theory.
Now, in order to support the philisophical theory, deniers will look for another convenient theory to support their position.
The exact argument can be applied towards the global warmists They cling to the science that has been found in error or at least questionable.
They reject even the possibility that C02 is NOT the great contributor to global warming they believe it is despite the reality of what has been happening with our climate.
"Global Warming" is not a philosophy or a religion but an observed phenomenon.
That's correct Rory please note the "OBSERVABLE" temperature moderation that has been happening for the last 10 years or so.
"Those who hold beliefs or philosophies that reject the possibility of any human contribution to observed climactic changes are continually seeking a scientific explanation that will suppor their philosophy."
Thing about it Rory is that this is the mode that the global warmists are now in and that the IPCC has been in for quiet a while now due to their belief that the question is answered the debate is over, they are not focusing on science to understand but science to confirm.
The last ten years of moderation and cooling has been met with differing ideas as to where the heat may have gone but no conclusive research explaining why the temperature has not risen despite the continual input of human produced C02 ever increasing amounts.
Despite the evidence showing that the IPCC conclusions questionable global warmists cling to their ideals refusing to allow doubt to be expressed.
This is a good time for those who faith in science rather than faith in consensus.
Consensus is political nothing more.
"Global warming has not stopped," said Amir Delju, senior scientific coordinator of the World Meteorological Organization's (WMO) climate program.
Last year was among the six warmest years since records began in the 1850s and the British Met Office said last week that 2008 will be the coolest year since 2000, partly because of a La Nina event that cuts water temperatures in the Pacific.
As I posted the IPCC has admitted that our earth's temperature has moderated and they have no idea why.
Their models that showed that the temperature would continue to rise with the continued input of man made C02 has been shown not accurate.
The fact that last year was the among the six warmists years is no different than exclaiming the fact that a year within 2007-2008 was the coolest in 30 years (it was).
What is important is the IPCC's models have been found in error, unreliable.
You just described theology, not science.
How did you get from is in one paragraph to seems in the next?
What is this? The Nancy Pelosi School of Rhetoric?