Study: Sun's Changes to Blame for Part of Global Warming
Live Science/Robert Roy Britt | October 3 2005
WhatReallyHappened has a great commentary on this....
This is the Galileo thing all over again. There is clear evidence that the sun is the primary control of the Earth's temperature. First, the cycle of hot planet and ice age matches exactly the cycle Earth's orbit as it slowly oscillates between more circular and more elliptical. More recently, the link between solar activity and Earth's temperature has been established for a decade. Finally, since the Earth has sent probes to Mars since 1976, it has been shown that Mars is getting warmer as well, despite the absence of SUVs.
But, if the Sun is making the Earth warmer, there will be no money for "fixes", no political "cause" with which to swindle the voters out of support, let alone a justification for further control over people's lives. So, like the supporters of epicycles looking at Galileo's numbers, the scientists shrug, say "It's possible, but what I have known all my life still applies."
Now, I am a big supporter of wise use of resources, but the geological record is clear. The Earth gets hotter and colder all the time. That change is NATURAL. We just came out of an ice age and we are still far cooler than Earth was during the Cretaceous. It is only the arrogance of man that suggests that the Earth can or should be frozen in its current configuration for the benefit of man.
Increased output from the Sun might be to blame for 10 to 30 percent of global warming that has been measured in the past 20 years, according to a new report.
Increased emissions of carbon dioxide and other heat-trapping gases still play a role, the scientists say.
But climate models of global warming should be corrected to better account for changes in solar activity, according to Nicola Scafetta and Bruce West of Duke University.
The findings were published online this week by the journal Geophysical Research Letters.
Scientists agree the planet is warming. Effects are evident in melting glaciers and reductions in the amount of frozen ground around the planet.
The new study is based in part on Columbia University research from 2003 in which scientists found errors in how data on solar brightness is interpreted. A gap in data, owing to satellites not being deployed after the Space Shuttle Columbia disaster, were filled by less accurate data from other satellites, Scafetta says.
The Duke analyses examined solar changes over 22 years versus 11 years used in previous studies. The cooling effect of volcanoes and cyclical shifts in ocean currents can have a greater negative impact on the accuracy of shorter data periods.
"The Sun may have minimally contributed about 10 to 30 percent of the 1980-2002 global surface warming," the researchers said in a statement today.
Many questions remain, however. For example, scientists do not have a good grasp of how much Earth absorbs or reflects sunlight.
"We don't know what the Sun will do in the future," Scafetta says. "For now, if our analysis is correct, I think it is important to correct the climate models so that they include reliable sensitivity to solar activity. Once that is done, then it will be possible to better understand what has happened during the past hundred years."