Some researchers believe that the solar cycle influences global climate changes. They attribute recent warming trends to cyclic variation. Skeptics, though, argue that there's little hard evidence of a solar hand in recent climate changes.
Now, a new research report from a surprising source may help to lay this skepticism to rest. A study from NASA’s Goddard Space Flight Center in Greenbelt, Maryland looking at climate data over the past century has concluded that solar variation has made a significant impact on the Earth's climate. The report concludes that evidence for climate changes based on solar radiation can be traced back as far as the Industrial Revolution.
Past research has shown that the sun goes through eleven year cycles. At the cycle's peak, solar activity occurring near sunspots is particularly intense, basking the Earth in solar heat. According to Robert Cahalan, a climatologist at the Goddard Space Flight Center, "Right now, we are in between major ice ages, in a period that has been called the Holocene."
Thomas Woods, solar scientist at the University of Colorado in Boulder concludes, "The fluctuations in the solar cycle impacts Earth's global temperature by about 0.1 degree Celsius, slightly hotter during solar maximum and cooler during solar minimum. The sun is currently at its minimum, and the next solar maximum is expected in 2012."
According to the study, during periods of solar quiet, 1,361 watts per square meter of solar energy reaches Earth's outermost atmosphere. Periods of more intense activity brought 1.4 watts per square meter (0.1 percent) more energy.
While the NASA study acknowledged the sun's influence on warming and cooling patterns, it then went badly off the tracks. Ignoring its own evidence, it returned to an argument that man had replaced the sun as the cause current warming patterns. Like many studies, this conclusion was based less on hard data and more on questionable correlations and inaccurate modeling techniques.
The inconvertible fact, here is that even NASA's own study acknowledges that solar variation has caused climate change in the past. And even the study's members, mostly ardent supports of AGW theory, acknowledge that the sun may play a significant role in future climate changes.
quote: O.K., so that accounts for 0.1 degree Celsius. However, the global warming is 0.5 degrees Celsius (see http://en.wikipedia.org/wiki/File:Instrumental_Tem... So I don't understand where the report
quote: One year doesn't prove anything. The general trend is that the earth is warming, like it or not, Mike.
quote: Also, regardless of this ongoing study you use, there's been numerous studies by NASA in the last year taking the opposite stance:
quote: But it does showcase a major flaw in AGW logic.
quote: Dual-format players become cheap and ubiquitous. The average consumer buys an HD movie without caring (or in some cases, knowing) its format. Just as they buy recordable DVDs today. Is there any doubt this is the eventual outcome? It won't be this year of course, and probably not in 2008. But eary 2009-- look out!
quote: Better than that-- if a year goes by, and my predictions have turned out false, I'll eat crow and post a lengthy reversal
quote: s the study shows, past solar activity has led to approximately 0.1 degrees C variation. What the study fails to look at is the fact that solar activity increased dramatically over twentieth century. This increase could easily account for the larger variation.
quote: What you will see if you actually do graph the data, however, is what appears to be roughly a sine-wave pattern that decided to start slanting upwards around 1920 or so.
quote: all you would expect to see is a sine wave with slightly increasing amplitude towards the end when graphing average temperatures.
quote: So the average would have to increase by 100 sunspots for every 0.1 degree of observed warming, for solar activity to be the primary culprit.