A new Ice Age approaches?

Old and busted: global warming.  New hotness: coldness.  Reports from three different studies released yesterday point to the possibility of an extended period of solar inactivity not seen for three hundred years, and one that could bring a new mini-Ice Age:

According to three studies released in the United States on Tuesday, experts believe the familiar sunspot cycle may be shutting down and heading toward a pattern of inactivity unseen since the 17th century.

The signs include a missing jet stream, fading spots, and slower activity near the poles, said experts from the National Solar Observatory and Air Force Research Laboratory.

‘This is highly unusual and unexpected,’ said Frank Hill, associate director of the NSO’s Solar Synoptic Network.

‘But the fact that three completely different views of the Sun point in the same direction is a powerful indicator that the sunspot cycle may be going into hibernation.’

NASA reminds us what happened during the last such extended period of hibernation, called the Maunder Minimum, occurred:

Early records of sunspots indicate that the Sun went through a period of inactivity in the late 17th century. Very few sunspots were seen on the Sun from about 1645 to 1715. Although the observations were not as extensive as in later years, the Sun was in fact well observed during this time and this lack of sunspots is well documented. This period of solar inactivity also corresponds to a climatic period called the “Little Ice Age” when rivers that are normally ice-free froze and snow fields remained year-round at lower altitudes. There is evidence that the Sun has had similar periods of inactivity in the more distant past.

The NSO and the US Air Force Research Laboratory announced the results yesterday, as the British newspaper The Register reported last night, and the NSO specifically mentioned another Maunder Minimum as a possible outcome:

The announcement made on 14 June (18:00 UK time) comes from scientists at the US National Solar Observatory (NSO) and US Air Force Research Laboratory. Three different analyses of the Sun’s recent behaviour all indicate that a period of unusually low solar activity may be about to begin. …

This could have major implications for the Earth’s climate. According to a statement issued by the NSO, announcing the research:

“An immediate question is whether this slowdown presages a second Maunder Minimum, a 70-year period with virtually no sunspots [which occurred] during 1645-1715.”

Obviously, the solution to this (from an AGW perspective) would be to immediately ramp up carbon emissions.  Why, we should start subsidizing fossil-fuel use and pay drivers a per-mile tax credit!  Build refineries, and fly lots of charter jet flights with only a handful of passengers!  Oh, wait — AGW activists like Al Gore already do that last one, don’t they?

Don’t buy your mukluks for Florida just yet.  This is still a hypothesis, not yet an immutable fact.  The NSO and USAFRL still needs to conduct research to see whether a new Maunder Minimum will come, or if this sunspot cycle has just hiccuped. (NASA notes in a sentence that The Register didn’t include that “The connection between solar activity and terrestrial climate is an area of on-going research.”)  That will take at least a couple of years to see what direction solar activity takes and what its impact on global temperatures might be, so no one should rush into policy “solutions” for climate in either direction.  Of course, this is also good advice for AGW hysterics who have been predicting the end of the world in the other direction for 20 years, and whose predictions have so far all failed to materialize.

Of course, if those AGW advocates suddenly convert to Maunder Minimists, why do I have the sneaking suspicion that the same solutions — central control of energy production and usage, elimination of fossil fuels — will be pushed?

Update: I was rightly upbraided in the comments by Badger40 for confusing “hypothesis” with “theory,” and I’ve changed the wording accordingly.  They mean two very different things in science, which I knew but got sloppy when writing that sentence.  Bear in mind that the decline in activity is not a hypothesis or theory, but actual data; the hypothesis is that it presages a new Maunder Minimum-type period of inactivity, which will cool the planet significantly enough for a new mini-Ice Age.

Update II: Anthony Watts and David Archibald explore another hypothesis of a less-onerous Dalton Minimum.  Note the graphs showing solar activity in Cycle 24 and also the North American snow cover over the last 40 years.  Since the 1970s — the last cooling period — the snow cover has abated significantly, and hasn’t expanded the last four cold winters, but we will need to see whether this starts expanding in the absence of solar activity.