What cooling mechanism?

[meemoeuk]

Of course, both mechansims are true. But which one is more powerful? And by how much?

Here's the total mechanism
During solar minium...
Sun's Lower magnetic field strength -> Less Solar wind -> More galactic cosmic rays -> Faster low level cloud formation.

Then the mechanism forks into 2 effects

a.) More low level cloud formation -> More sunlight reflected back into space -> Earth cools

b.) Faster low level cloud formation -> Atmospheric water spends less time in atmos before returning to surface. -> Less of main greenhouse agent in atmos -> Earth cools.

[william]

There is a possible second mechanism.

There is this paper that predicts that an increase in GCR and GCR velocity (energy) will cause a reduction in ozone which particularly in polar regions results in colder winters.

focus.aps.org/story/v8/st8


wattsupwiththat.com/2008/10/25/new-theory-predicts-the-largest-ozone-hole-over-antarctica-will-occur-this-month/

[rustyphillips]

reduced high level cloud cover
clearer nighttime skys
lower overnite temperatures
total solar irradiance drops a very tiny amount

net result is lower daily average temperatures

[jimg]

How about....
Energy introduced in the polar regions during solar maximum reduces the amount of heat lost at the poles. This takes the form of magnetic directly coupling with polar atmosphere to the sun. strong Auroras are present pumping in hundreds of billions of joules to the polar region. (See Themis mission)

During solar minimum, the sun-pole effects are minimized allowing greater heat loss. Deep solar minimums enhancing the thermohaline cycle.

Of course this doesn't negate the UV/energetic particle/ozone interactions, possible cloud formation due to cosmic particles.
Particle collection in the Van Allen belts, etc, etc.

Of course, all that is meaningless since CO2 controls the climate and not the sun or any other phenomena!

[meemoeuk]

Hmm, maybe I'm selecting less important climate factors now but I was thinking this one could still be quite big.

If galactic rays are causing prompter cloud formation and cloud life cycle, this should mean more clouds over the oceans and less clouds over the continents, since the clouds will have less to drift around before raining.
Well, Svensmark argued GRs will cause global cooling via more clouds, but if what I'm thinking is right, not only will there be more sunlight reflected off Earth due to these clouds, but the shifting average position of the clouds from continents to oceans will also be a negative temperture factor.
The oceans are better at stashing incident sunlight energy than the continents.

Anyone else consider this a substancial factor?

[poitsplace]

Let's not forget about the substantial shift in higher frequency UV from the sun. This is a significant portion of the sun's output and comes at the expense of other wavelengths. In response to the lower input of UV (and other solar forcings) the outer atmosphere then falls by 100 miles (observed) which reduces the potential capture cross section of the earth by as much as 2.7% (probably less than that but still very significant).

[nautonnier]

Feb 20, 2009 4:35:19 GMT poitsplace said:

Let's not forget about the substantial shift in higher frequency UV from the sun. This is a significant portion of the sun's output and comes at the expense of other wavelengths. In response to the lower input of UV (and other solar forcings) the outer atmosphere then falls by 100 miles (observed) which reduces the potential capture cross section of the earth by as much as 2.7% (probably less than that but still very significant).

Taking that hypothesis a little further -

The radial extent of atmosphere shrinks by 100 miles - this must have an effect on GLAAM. Will there be any connection with the SSW events?