[troutman]

http://www.slate.com/blogs/bad_astro...i_ice_age.html

While changes in the Sun’s activity have a very marginal effect on global warming and/or cooling, human contributions to carbon dioxide in our atmosphere completely overwhelm the Sun’s influence. It’s like tapping on your brakes as your car plunges headlong into a brick wall at 100 kilometers per hour.

This new claim comes from a presentation at conference by Valentina Zharkova, a mathematician and scientist at Northumbria University. To be clear, she’s not predicting a 60 percent drop in the light and heat emitted by the Sun, but a drop in magnetic activity in the Sun. This has only a marginal effect on the Sun’s light/heat output. Also, if you listen to an interview with her on Radio New Zealand, you’ll hear some unusual claims, like the climates on other planets are changing due to the Sun—a red herring when it comes to climate change on Earth. She also admits at the end she doesn’t do atmospheric research, so the claim that lowered magnetic activity of the Sun can cause an ice age here on Earth is in my opinion shaky at best.

In a nutshell, the Sun goes through an 11-year cycle of magnetic activity. When it peaks, sunspots are more common. You might think that means less heat from the Sun, since sunspots are cooler and darker. But they have bright rims (called faculae) that more than make up for the cooler interior regions. So, when solar activity is high, and sunspots abound, the Sun is actually very marginally warmer.


The sunspot cycle this go-round was weak, and may be weak in the next cycle as well. No one really knows. There has been research asking what would happen if it is weak next time and concludes it will have moderate localized effects—not global cooling. In fact, the very first line of the abstract of that paper is this:

Any reduction in global mean near-surface temperature due to a future decline in solar activity is likely to be a small fraction of projected anthropogenic warming.

http://www.iflscience.com/environmen...global-warming

IFLScience has spoken to the researcher who started the furor: Valentina Zharkova. She announced the findings from her team's research on solar activity last week at the Royal Astronomical Society. She noted that her team didn't realize how much of an impact their research would have on the media, and that it was journalists (including ourselves) who picked up on the possible impact on the climate. However, Zharkova says that this is not a reason to dismiss this research or the predictions about the environment.

“We didn't mention anything about the weather change, but I would have to agree that possibly you can expect it,” she informed IFLScience.

The conditions during this next predicted minimum will still be chilly: “It will be cold, but it will not be this ice age when everything is freezing like in the Hollywood films,” Zharkova chuckled.

However, Zharkova ends with a word of warning: not about the cold but about humanity's attitude toward the environment during the minimum. We must not ignore the effects of global warming and assume that it isn't happening. “The Sun buys us time to stop these carbon emissions,” Zharkova says. The next minimum might give the Earth a chance to reduce adverse effects from global warming.