Global Warming Objections, Part III: Sunspot Activity

by Chuck Hall

Research from climate scientists all over the world increasingly demonstrates that human activities are playing a part in global warming. Still, there are those who object to the idea that human activities are responsible. These critics of climate change science must answer the question: “If carbon dioxide isn’t responsible for the increase in global average temperature, what is?”
Those who wish to deny the prevailing scientific opinion have attempted to come up with alternative solutions to the question of climate change. Two alternate explanations for global warming seem to be gaining popularity.
The first explanation is that water vapor is a greenhouse gas, and that increases in water vapor across the globe are responsible for global warming. No proponent of this particular theory has yet been able to explain where the sudden increase in water vapor came from, nor why it began in the first place. The second explanation is that sunspots are causing it. In other words, ‘hot spots’ on the surface of the sun produce more heat, and as this heat travels to Earth, it causes increases in global temperature.
Note also that neither of these theories explains why the increase in carbon dioxide emissions in our atmosphere is positively correlated with the increase in global temperature. In other words, both the sunspot theory and the water vapor theory ignore carbon dioxide altogether, even though it is a demonstrable fact that carbon dioxide in our atmosphere has been steadily increasing.
On the sunspot theory, solar astronomer Peter Foukal says, “There has been an intuitive perception that the sun's variable degree of brightness, the coming and going of sunspots for instance, might have an impact on climate."
Foukal says that most climate models (including ones used by the Intergovernmental Panel on Climate Change) already incorporate the effects of the sun's waxing and waning power on Earth's weather.
According to a study by Foukal (Nature Magazine, September 2006), the difference in temperature caused by sunspot activity is simply far too small to contribute significantly to global warming. Foukal and his team of researchers gathered sunspot activity data from as far back as 1874 and attempted to correlate these records with temperature records gleaned from ice core samples. They found that the data simply did not match up.
The bottom line is that there is an only 0.1% temperature variance in sunspot activity. According to Foukal, this variance is far too small to have any major impact on the overall global average temperature of the Earth. It also doesn’t explain the correlation between increased carbon dioxide in our atmosphere and increased global average temperature. In short, the sunspot theory is not a credible or plausible explanation for global warming.