big kahuna wrote:
As far as that solution to global warming, though, I think we're more likely to see at least a temporary 'fix' emanate from the upcoming predicted solar Grand Minimum
, a period during which our Sun will become unusually cool, probably starting in the 2050s.
There may have been Grand Minimums in the past, and the famed Maunder Minimum saw temperatures from 1645 to 1715 particularly low in many parts of Europe. This is the period during which London's Thames River was noted to have frozen over. Funnily, it actually warmed up Alaska and Greenland.
A Grand Minimum could see the Sun become 7% cooler than its usual minimum, which is cool enough. Such a decline would have a strong effect on Earth's global temps.
Would like to point out a couple of things here:
The scientific paper that was cited by the story you linked to doesn't say anything remotely close to "could see the Sun become 7% cooler than its usual minimum".
What the paper says is that, based on a study of 33 Sun-like stars, and a linear regression "we estimate a range in UV flux of 9.3% over solar cycle 22 and a reduction of 6.9% below solar cycle minimum
under a grand minimum."
So what would happen if the sun's UV output dropped by 7%? What does that do to total solar irradiance? The answer is "not much" - the variation in UV at the top of the Earth's atmosphere (TOA) corresponding to a drop of 7% would be about 2 Watts per square meter. Compare this to the total TOA insolation, which is around 1360 W/m2. It's well-known that the total energy output from the sun varies only a few tenths of a percent over the solar cycle
That's not to say that the UV isn't important. UV strongly affects the structure of the upper atmosphere by creating the ozone layer which itself absorbs UV and creates heat, affecting the thermal structure and winds in the upper atmosphere. And that's an active area of research.