Sun to Blame for Global Warming
by John Carlisle
Those looking for the culprit responsible for global warming have missed the obvious choice - the sun. While it may come as a newsflash to some, scientific evidence conclusively shows that the sun plays a far more important role in causing global warming and global cooling than any other factor, natural or man-made. In fact, what may very well be the ultimate ironic twist in the global warming controversy is that the same solar forces that caused 150 years of warming are on the verge of producing a prolonged period of cooling.
The evidence for future cooling is supported by considerable scientific research that has only recently begun to come to light. It wasn't until 1980, with the aid of NASA satellites, that scientists definitively proved that the sun's brightness - or radiance - varies in intensity, and that these variations occur in predictable cyclical patterns. This was a crucial discovery because the climate models used by greenhouse theory proponents always assumed that the sun's radiance was constant. With that assumption in hand, they could ignore solar influences and focus on other influences, including human.
That turned out to be a reckless assumption. Further investigation revealed that there is a strong correlation between the variations in solar irradiance and fluctuations in the Earth's temperature. When the sun gets dimmer, the Earth gets cooler; when the sun gets brighter, the Earth gets hotter. So important is the sun in climate change that half of the 1.5° F temperature increase since 1850 is directly attributable to changes in the sun. According to NASA scientists David Lind and Judith Lean, only one-quarter of a degree can be ascribed to other causes, such as greenhouse gases, through which human activities can theoretically exert some influence.
The correlation between major changes in the Earth's temperature and changes in solar radiance is quite compelling. A perfect example is the Little Ice Age that lasted from 1650 to 1850. Temperatures in this era fell to as much as 2° F below today's temperature, causing the glaciers to advance, the canals in Venice to freeze and major crop failures. Interestingly, this dramatic cooling happened in a period when the sun's radiance had fallen to exceptionally low levels. Between 1645 and 1715, the sun was in a stage that scientists refer to as the Maunder Minimum. In this minimum, the sun has few sunspots and low magnetism which automatically indicates a lower radiance level. When the sun began to emerge from the minimum, radiance increased and by 1850 the temperature had warmed up enough for the Little Ice Age to end.
The Maunder Minimum is not an isolated event: it is a cyclical phenomenon that typically appears for 70 years following 200-300 years of warming. With only a few exceptions, whenever there is a solar minimum, the Earth gets colder. For example, Europe in the 13th and 15th Centuries experienced significantly lower temperatures and in both cases the cold spells coincided with a minimum. Similar correlations were found in the 9th Century and again in the 7th Century. Since 8700 B.C., there have been at least ten major cold periods similar to the Little Ice Age. Nine of those ten cold spells coincided with Maunder Minima.
There is no reason to believe that this 10,000-year-old cycle of solar-induced warming and cooling will change. Dr. Sallie Baliunas, an astrophysicist with the Harvard-Smithsonian Center for Astrophysics and one of the nation's leading experts on global climate change, believes that we may be nearing the end of a solar warming cycle. Since the last minimum ended in 1715, Baliunas says there is a strong possibility that the Earth will start cooling off in the early part of the 21st Century.
Indeed, it could already be happening. Of the 1.5° F in warming the planet experienced over the last 150 years, two-thirds of that increase, or one degree, occurred between 1850 and 1940. In the last 50 years, the planetary temperature increased at a significantly slower rate of 0.5° F - precisely when dramatically increasing amounts of man-made carbon dioxide emissions should have been accelerating warming. Further buttressing the arguments for future cooling is the evidence from NASA satellites that the global temperature has actually fallen 0.04° F since 1979.
Of course, it is impossible to precisely predict when solar radiance will drop and global temperatures will begin falling. But one thing is certain: There is little evidence that mankind is responsible for global warming. There is considerable evidence that the sun causes warming and will most likely stimulate cooling in the not so distant future.
John K. Carlisle is the Director of The National Center for Public Policy Research's Environmental Policy Task Force. Comments may be sent to JCarlisle@nationalcenter.org.
Showing posts with label Solar cause of GW. Show all posts
Showing posts with label Solar cause of GW. Show all posts
Monday, June 2, 2008
Here comes the Sun.........
Sun Blamed for Warming of Earth and Other Worlds
By Ker Than, LiveScience Staff Writer
posted: 12 March 2007 07:27 am ET
Earth is heating up lately, but so are Mars, Pluto and other worlds in our solar system, leading some scientists to speculate that a change in the sun’s activity is the common thread linking all these baking events.
Others argue that such claims are misleading and create the false impression that rapid global warming, as Earth is experiencing, is a natural phenomenon.
While evidence suggests fluctuations in solar activity can affect climate on Earth, and that it has done so in the past, the majority of climate scientists and astrophysicists agree that the sun is not to blame for the current and historically sudden uptick in global temperatures on Earth, which seems to be mostly a mess created by our own species.
Wobbly Mars
Habibullo Abdussamatov, the head of space research at St. Petersburg's Pulkovo Astronomical Observatory in Russia, recently linked the attenuation of ice caps on Mars to fluctuations in the sun's output. Abdussamatov also blamed solar fluctuations for Earth’s current global warming trend. His initial comments were published online by National Geographic News.
“Man-made greenhouse warming has [made a] small contribution [to] the warming on Earth in recent years, but [it] cannot compete with the increase in solar irradiance,” Abdussamatov told LiveScience in an email interview last week. “The considerable heating and cooling on the Earth and on Mars always will be practically parallel."
But Abdussamatov’s critics say the Red Planet’s recent thawing is more likely due to natural variations in the planet’s orbit and tilt. On Earth, these wobbles, known as Milankovitch cycles, are thought to contribute to the onset and disappearance ice ages.
“It’s believed that what drives climate change on Mars are orbital variations,” said Jeffrey Plaut, a project scientist for NASA’s Mars Odyssey mission. “The Earth also goes through orbital variations similar to that of Mars.”
As for Abdussamatov’s claim that solar fluctuations are causing Earth’s current global warming, Charles Long, a climate physicist at Pacific Northwest National Laboratories in Washington, says the idea is nonsense.
“That’s nuts,” Long said in a telephone interview. “It doesn’t make physical sense that that’s the case.”
In 2005, Long’s team published a study in the journal Science showing that Earth experienced a period of “solar global dimming” from 1960 to 1990, during which time solar radiation hitting our planet’s surface decreased. Then from the mid-1990’s onward, the trend reversed and Earth experienced a “solar brightening.”
These changes were not likely driven by fluctuations in the output of the Sun, Long explained, but rather increases in atmospheric clouds or aerosols that reflected solar radiation back into space.
Other warming worlds
Others have pointed out anomalous warming on other worlds in our solar system.
Benny Peiser, a social anthropologist at Liverpool John Moores University who monitors studies and news reports of asteroids, global warming and other potentially apocalyptic topics, recently quoted in his daily electronic newsletter the following from a blog called Strata-Sphere:
“Global warming on Neptune's moon Triton as well as Jupiter and Pluto, and now Mars has some [scientists] scratching their heads over what could possibly be in common with the warming of all these planets ... Could there be something in common with all the planets in our solar system that might cause them all to warm at the same time?”
Peiser included quotes from recent news articles that take up other aspects of the idea.
“I think it is an intriguing coincidence that warming trends have been observed on a number of very diverse planetary bodies in our solar system,” Peiser said in an email interview. “Perhaps this is just a fluke.”
In fact, scientists have alternative explanations for the anomalous warming on each of these other planetary bodies.
The warming on Triton, for example, could be the result of an extreme southern summer on the moon, a season that occurs every few hundred years, as well as possible changes in the makeup of surface ice that caused it to absorb more of the Sun’s heat.
Researchers credited Pluto’s warming to possible eruptive activity and a delayed thawing from its last close approach to the Sun in 1989.
And the recent storm activity on Jupiter is being blamed on a recurring climatic cycle that churns up material from the gas giant’s interior and lofts it to the surface, where it is heated by the Sun.
Sun does vary
The radiation output of the Sun does fluctuate over the course of its 11-year solar cycle. But the change is only about one-tenth of 1 percent—not substantial enough to affect Earth’s climate in dramatic ways, and certainly not enough to be the sole culprit of our planet’s current warming trend, scientists say.
“The small measured changes in solar output and variations from one decade to the next are only on the order of a fraction of a percent, and if you do the calculations not even large enough to really provide a detectable signal in the surface temperature record,” said Penn State meteorologist Michael Mann.
The link between solar activity and global warming is just another scapegoat for human-caused warming, Mann told LiveScience.
“Solar activity continues to be one of the last bastions of contrarians,” Mann said. “People who don’t accept the existence of anthropogenic climate change still try to point to solar activity.”
The Maunder Minimum
This is not to say that solar fluctuations never influence Earth’s climate in substantial ways. During a 75-year period beginning in 1645, astronomers detected almost no sunspot activity on the Sun. Called the “Maunder Minimum,” this event coincided with the coldest part of the Little Ice Age, a 350-year cold spell that gripped much of Europe and North America.
Recent studies have cast doubt on this relationship, however. New estimates of the total change in the brightness of the Sun during the Maunder Minimum suggest it was only fractions of a percent, and perhaps not enough to create the global cooling commonly attributed to it.
“The situation is pretty ambiguous,” said David Rind, a senior climate researcher at NASA Goddard Institute for Space Studies, who has modeled the Maunder Minimum.
Based on current estimates, even if another Maunder Minimum were to occur, it might result in an average temperature decrease of about 2 degrees Fahrenheit, Rind said.
This would still not be enough to counteract warming of between 2 to 12 degrees Fahrenheit from greenhouse gases by 2100, as predicted by the latest Intergovernmental Panel on Climate Change (IPCC) report.
LiveScience staff writer Andrea Thompson contributed to this article.
More to Explore
10 Surprising Results of Global Warming
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Video: Goldilocks and the Greenhouse
How You Can Fight Global Warming
Global Warming Features
Earth Will Survive Global Warming, But Will We?
Strange Weather's Loose Link to Global Warming
Global Warming or Just Hot Air? A Dozen Different Views
Recent Climate Change News
Protecting Ozone Layer Also Slowed Global Warming
Surprising New Arctic Inhabitants: Trees
Earth's Polar Regions Target of Year-Long Study
By Ker Than, LiveScience Staff Writer
posted: 12 March 2007 07:27 am ET
Earth is heating up lately, but so are Mars, Pluto and other worlds in our solar system, leading some scientists to speculate that a change in the sun’s activity is the common thread linking all these baking events.
Others argue that such claims are misleading and create the false impression that rapid global warming, as Earth is experiencing, is a natural phenomenon.
While evidence suggests fluctuations in solar activity can affect climate on Earth, and that it has done so in the past, the majority of climate scientists and astrophysicists agree that the sun is not to blame for the current and historically sudden uptick in global temperatures on Earth, which seems to be mostly a mess created by our own species.
Wobbly Mars
Habibullo Abdussamatov, the head of space research at St. Petersburg's Pulkovo Astronomical Observatory in Russia, recently linked the attenuation of ice caps on Mars to fluctuations in the sun's output. Abdussamatov also blamed solar fluctuations for Earth’s current global warming trend. His initial comments were published online by National Geographic News.
“Man-made greenhouse warming has [made a] small contribution [to] the warming on Earth in recent years, but [it] cannot compete with the increase in solar irradiance,” Abdussamatov told LiveScience in an email interview last week. “The considerable heating and cooling on the Earth and on Mars always will be practically parallel."
But Abdussamatov’s critics say the Red Planet’s recent thawing is more likely due to natural variations in the planet’s orbit and tilt. On Earth, these wobbles, known as Milankovitch cycles, are thought to contribute to the onset and disappearance ice ages.
“It’s believed that what drives climate change on Mars are orbital variations,” said Jeffrey Plaut, a project scientist for NASA’s Mars Odyssey mission. “The Earth also goes through orbital variations similar to that of Mars.”
As for Abdussamatov’s claim that solar fluctuations are causing Earth’s current global warming, Charles Long, a climate physicist at Pacific Northwest National Laboratories in Washington, says the idea is nonsense.
“That’s nuts,” Long said in a telephone interview. “It doesn’t make physical sense that that’s the case.”
In 2005, Long’s team published a study in the journal Science showing that Earth experienced a period of “solar global dimming” from 1960 to 1990, during which time solar radiation hitting our planet’s surface decreased. Then from the mid-1990’s onward, the trend reversed and Earth experienced a “solar brightening.”
These changes were not likely driven by fluctuations in the output of the Sun, Long explained, but rather increases in atmospheric clouds or aerosols that reflected solar radiation back into space.
Other warming worlds
Others have pointed out anomalous warming on other worlds in our solar system.
Benny Peiser, a social anthropologist at Liverpool John Moores University who monitors studies and news reports of asteroids, global warming and other potentially apocalyptic topics, recently quoted in his daily electronic newsletter the following from a blog called Strata-Sphere:
“Global warming on Neptune's moon Triton as well as Jupiter and Pluto, and now Mars has some [scientists] scratching their heads over what could possibly be in common with the warming of all these planets ... Could there be something in common with all the planets in our solar system that might cause them all to warm at the same time?”
Peiser included quotes from recent news articles that take up other aspects of the idea.
“I think it is an intriguing coincidence that warming trends have been observed on a number of very diverse planetary bodies in our solar system,” Peiser said in an email interview. “Perhaps this is just a fluke.”
In fact, scientists have alternative explanations for the anomalous warming on each of these other planetary bodies.
The warming on Triton, for example, could be the result of an extreme southern summer on the moon, a season that occurs every few hundred years, as well as possible changes in the makeup of surface ice that caused it to absorb more of the Sun’s heat.
Researchers credited Pluto’s warming to possible eruptive activity and a delayed thawing from its last close approach to the Sun in 1989.
And the recent storm activity on Jupiter is being blamed on a recurring climatic cycle that churns up material from the gas giant’s interior and lofts it to the surface, where it is heated by the Sun.
Sun does vary
The radiation output of the Sun does fluctuate over the course of its 11-year solar cycle. But the change is only about one-tenth of 1 percent—not substantial enough to affect Earth’s climate in dramatic ways, and certainly not enough to be the sole culprit of our planet’s current warming trend, scientists say.
“The small measured changes in solar output and variations from one decade to the next are only on the order of a fraction of a percent, and if you do the calculations not even large enough to really provide a detectable signal in the surface temperature record,” said Penn State meteorologist Michael Mann.
The link between solar activity and global warming is just another scapegoat for human-caused warming, Mann told LiveScience.
“Solar activity continues to be one of the last bastions of contrarians,” Mann said. “People who don’t accept the existence of anthropogenic climate change still try to point to solar activity.”
The Maunder Minimum
This is not to say that solar fluctuations never influence Earth’s climate in substantial ways. During a 75-year period beginning in 1645, astronomers detected almost no sunspot activity on the Sun. Called the “Maunder Minimum,” this event coincided with the coldest part of the Little Ice Age, a 350-year cold spell that gripped much of Europe and North America.
Recent studies have cast doubt on this relationship, however. New estimates of the total change in the brightness of the Sun during the Maunder Minimum suggest it was only fractions of a percent, and perhaps not enough to create the global cooling commonly attributed to it.
“The situation is pretty ambiguous,” said David Rind, a senior climate researcher at NASA Goddard Institute for Space Studies, who has modeled the Maunder Minimum.
Based on current estimates, even if another Maunder Minimum were to occur, it might result in an average temperature decrease of about 2 degrees Fahrenheit, Rind said.
This would still not be enough to counteract warming of between 2 to 12 degrees Fahrenheit from greenhouse gases by 2100, as predicted by the latest Intergovernmental Panel on Climate Change (IPCC) report.
LiveScience staff writer Andrea Thompson contributed to this article.
More to Explore
10 Surprising Results of Global Warming
Emerging Environmental Technologies
Video: Goldilocks and the Greenhouse
How You Can Fight Global Warming
Global Warming Features
Earth Will Survive Global Warming, But Will We?
Strange Weather's Loose Link to Global Warming
Global Warming or Just Hot Air? A Dozen Different Views
Recent Climate Change News
Protecting Ozone Layer Also Slowed Global Warming
Surprising New Arctic Inhabitants: Trees
Earth's Polar Regions Target of Year-Long Study
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