Thursday, January 07, 2010


clipped from

Solar geomagnetic activity is at an all time low – what does this mean for climate?

We then had a string of sunspots in December that marked what many saw as a rejuvenation of solar cycle 24 after a long period of inactivity. See December sunspots on the rise

It even prompted people like Joe Romm to claim:

The hottest decade ends and since there’s no Maunder mininum — sorry deniers! — the hottest decade begins

But what Joe doesn’t understand is that sunspots are just one proxy, the simplest and most easily observed, for magnetic activity of the sun. It is the magnetic activity of the sun which is central to Svensmark’s theory of galactic cosmic ray modulation, which may affect cloud cover formation on earth, thus affecting global temperatures.

With the sunspot activity in December, I thought surely the Ap index would go up. Instead, it crashed.
back to 1844 when measurements first started, the significance of this value of “1″ becomes evident.