Skip to comments.Study acquits sun of climate change, blames humans
Posted on 09/13/2006 2:01:24 PM PDT by Ernest_at_the_Beach
OSLO (Reuters) - The sun's energy output has barely varied over the past 1,000 years, raising chances that global warming has human rather than celestial causes, a study showed on Wednesday.
Researchers from Germany, Switzerland and the United States found that the sun's brightness varied by only 0.07 percent over 11-year sunspot cycles, far too little to account for the rise in temperatures since the Industrial Revolution.
"Our results imply that over the past century climate change due to human influences must far outweigh the effects of changes in the sun's brightness," said Tom Wigley of the U.S. National Center for Atmospheric Research.
Most experts say emissions of greenhouse gases, mainly from burning fossil fuels in power plants, factories and cars, are the main cause of a 0.6 Celsius (1.1 F) rise in temperatures over the past century.
A dwindling group of scientists says that the dominant cause of warming is a natural variation in the climate system, or a gradual rise in the sun's energy output.
"The solar contribution to warming over the past 30 years is negligible," the researchers wrote in the journal Nature of evidence about the sun from satellite observations since 1978.
They also found little sign of solar warming or cooling when they checked telescope observations of sunspots against temperature records going back to the 17th century.
They then checked more ancient evidence of rare isotopes and temperatures trapped in sea sediments and Greenland and Antarctic ice and also found no dramatic shifts in solar energy output for at least the past millennium.
SUN NOT GUILTY
"This basically rules out the sun as the cause of global warming," Henk Spruit, a co-author of the report from the Max Planck Institute in Germany, told Reuters.
Many scientists say greenhouse gases might push up world temperatures by perhaps another 3 Celsius by 2100, causing more droughts, floods, disease and rising global sea levels.
Spruit said a "Little Ice Age" around the 17th century, when London's Thames River froze, seemed limited mainly to western Europe and so was not a planet-wide cooling that might have implied a dimmer sun.
And global Ice Ages, like the last one which ended about 10,000 years ago, seem linked to cyclical shifts in the earth's orbit around the sun rather than to changes in solar output.
"Overall, we can find no evidence for solar luminosity variations of sufficient amplitude to drive significant climate variations on centennial, millennial or even million-year timescales," the report said.
Solar activity is now around a low on the 11-year cycle after a 2000 peak, when bright spots called faculae emit more heat and outweigh the heat-plugging effect of dark sunspots. Both faculae and dark sunspots are most common at the peaks.
Still, the report also said there could be other, more subtle solar effects on the climate, such as from cosmic rays or ultraviolet radiation. It said they would be hard to detect.
"Still, the report also said there could be other, more subtle solar effects on the climate, such as from cosmic rays or ultraviolet radiation. It said they would be hard to detect"
Oh man. buried at the bottom of the story you find the above.
Could we have a careful cycle of measurement time choices....what about past cycles of warming and cooling?
Wow! Scientists have kept records for so long on solar energy. Who would have thunk it?
If the earth's climate is not stable, i.e, it varies from one age to another, how can anyone declare with certainty that human activity is causing warming?
How can one sitting on a beach really know whether the next wave was natural or caused by a ship out at sea?
And what about the previous thousands of years?
Chief Priests of the Church of Global Warming pronounce anathema on any data that does not validate their preconceived assumption.
More likely changing ocean currents affect short and long term weather patterns.
I've sat on the beach and wondered about that.....saw some waves yesterday....and saw no ships....
Oh, yeah, THAT'S conclusive.
The earth is in a death spiral and there is no chance of escaping the approaching disaster.
Women and children will be hardest hit.
So what does that tell us about solar output during the Lesser Dryas or the Little Ice Age?
Meanwhile, we have documented observational records that there were very few sunspots during the Little Ice Age - so the sun DID behave differently during that time.
More bullshiite from the globaloney warming types.
I wonder if humans, and not the sun, are responsible for the retreating snow pack on the southern pole of Mars, as tracked by the orbital surveyor since 1997.
Further study aquits humans of climate change, blames Bush.
If you are looking for a question with a pre-conceived answer, you can find it almost every time.
They already decided it was humans creating the problem, now they have to make the research say the same thing they have said.
And what about the previous thousands of years?
The authors used a blend of seven recent reconstructions of Northern Hemisphere temperature over the past millennium to test the effects of long-term changes in brightness.
So they manufactured a fraudulent series of models to prove their preconceived notions. That is a completely manufacture propaganda statement. They have NO data to back that claim up at all. More fraudulent Junk Science propaganda. They just went out and stated their political propaganda as "Science" these are not scientists at all.