Solar activity and Global Warming

[Sibling Zono (anon1mat0)]

Ok, this one is also brought to you by Discover Magazine, a (somewhat) dissenting voice regarding global warming (another clue regarding the change in editorial policy, that and the free DVD with a Shell oil infomercial bundled with the magazine). None the less a valid argument:

The basic idea is that solar activity can turn the cloudiness up and down, which has an effect on the warming or cooling of earth's surface temperature. The key agents in this are cosmic rays (...). These energetic particles have to enter into what we call the heliosphere, which is the large volume of space that is dominated by our sun, through the solar wind, which is a plasma of electrons, atomic nuclei, and associated magnetic fields that are streaming nonstop from the sun. Cosmic rays particles have to penetrate the sun's magnetic field. And if the sun and the solar wind are very active -as they are right now-  they will not allow so many cosmic rays to reach Earth. Fewer cosmic rays mean fewer clouds will be formed, and so there will be a warmer Earth. If the sun and the solar wind are not so active, then more cosmic rays can come in. That means more clouds[reflecting away more sunlight] and a cooler Earth

During the interview the guy says that he thinks that solar activity (with the mechanism he is theorizing) should be included (to the CO2 effect) in weather simulations regarding global warming.

The question I have is exactly how this activity affects cosmic rays; IIUC, all cosmic rays that pass through the heliosphere (that covers all the solar system) would be affected, but that would prevent cloud formation all over the planet, meaning that while the energy that comes directly from the sun can come in, at the other side of the planet the absence of those clouds would allow heat to escape. Am I understanding it in a very simplistic manner?

For reference I supply this old link, because the current edition isn't online yet.

[beagle]

Personally I believe it's very respectable to consider solar activity as a driver of climate.  As someone once said, whenever you agree with the majority you need to question whether you might be wrong.
I have a sneaky suspicion cold winters might make a come-back once sunspot activity turns.

There is a measure of reflectivity of the Earth from space (called albedo and with a value of about 0.39). It would be interesting to see if there has been any correlation of that with Solar activity, but probably satellites haven't been around long enough.

On the clouds missing on both sides question I think it's a question of black body radiation temperatures.

The sunlight coming in on the solar facing side of the Earth represents a higher temperature (so higher frequency and energy) than the energy radiating away on the dark side, so a lower albedo results in a net energy gain (probably exacerbated when you take the permeability of the atmosphere at different frequencies into account).
As an analogy a greenhouse has glass that lets radiation in and out,  but that doesn't stop it heating up in sunlight.

At least that's the simplified argument (there's also the issue that clouds trap geothermal, industrial,solar  etc heat beneath them whether it's night or day).

I expect Swatopluk has the complete set of differential equations to hand

[Swatopluk]

I hate this type of mathematics. Haven't I calculated heat exchangers far too often already.

Sun spot activity has an influence on the extent of the atmosphere thus influencing satellites (higher friction=>more fuel needed to keep the height or reduced lifetime.) But sunspots follow cycles that are long known and are quite regular and not in rhythm with the larger climate pattern (though maybe* with normal weather).

*Have to check it. I keep forgetting.