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So, in order to trigger another LIA, a new grand solar minimum would have to cause about 1°C cooling, plus it would have to offset the continued human-caused global warming of 1 to 5°C by 2100, depending on how our greenhouse gas emissions change over the next century.

In the Jyllands-Posten article, Henrik Svensmark (the main scientist behind the hypothesis that the sun has a significant indirect impact on global climate via galactic cosmic rays) was a bit more measured, suggesting,

“I can imagine that it will become 0.2°C colder. I would be surprised if it became 1–2°C”

So these two articles are suggesting that a grand solar minimum could have a net cooling effect in the ballpark of 1 to 6°C, depending on how human greenhouse gas emissions change over the next century. Is it plausible that a grand solar minimum could make that happen?

The short answer is, ‘No.’

Fortunately, Solar Output is Stable

We’re fortunate that the amount of solar radiation reaching the Earth’s surface is very stable. Climate contrarians will often ask if we’d prefer if the planet were warming or cooling, suggesting that global warming is a good thing because at least the planet isn’t getting colder. This is a false dichotomy – an ideal climate is a stable one………

Peer-Reviewed Research Says Global Warming will Continue

There have been several studies in recent years investigating what impact another grand solar minimum would have on global surface temperatures, since solar research suggests it’s possible we could be due for another extended solar minimum. Generally these studies will run climate model simulations under a given greenhouse gas emissions scenario with stable solar activity, then run the same scenario with the sun going into a grand minimum, and look at the difference in resulting global surface temperature changes.

Using this approach, Feulner & Rahmstorf (2010) (PDF available here) estimated that another solar minimum equivalent to the Dalton and Maunder minima would cause 0.09°C and 0.26°C cooling, respectively………

Human Influence on Climate Change is Bigger than the Sun’s

The bottom line is that the sun and the amount of solar radiation reaching Earth are very stable. Even during the Maunder and Dalton grand solar minima, global cooling was relatively small – smaller than the amount of global warming caused by human greenhouse gas emissions over the past century.

A new grand solar minimum would not trigger another LIA; in fact, the maximum 0.3°C cooling would barely make a dent in the human-caused global warming over the next century. While it would be enough to offset to about a decade’s worth of human-caused warming, it’s also important to bear in mind that any solar cooling would only be temporary, until the end of the solar minimum.

The science is quite clear that the human influence on climate change has become bigger than the sun’s. At this point, speculation about another mini ice age is pure fantasy. http://www.theguardian.com/environment/climate-consensus-97-per-cent/2013/aug/14/global-warming-solar-minimum-barely-dent