[CraigS]

Hi Orestis;

Goodness me .. what a terrific question ..!

Ok, so I'm no solar expert but I believe the current theory on all this goes as per my below comments. (Others are free to correct me, if I've got it wrong. My motivation is purely that I believe these questions are too good to go unanswered - this is my best shot at it):

Originally Posted by orestis

Hi everyone,

I was going to post this in the obs forum but this is a scientific question so i thought i'll post it here.

From what i understand,
Granules are convection cells on the photosphere and radiate away both light and heat.

Granules observed in the photosphere, are presently believed to be the 'tops' of columns of rising plasma within the so called solar 'convective zone'.

Sunspots consist of an Umbra and Penumbra,they are considerably cooler than the photosphere,with the photosphere being 6000k,the penumbra 5600k and the umbra 4000k.

The faculae on the other hand are several hundred degrees hotter than the photosphere.

A 'plage' is a bright region in the chromosphere of the Sun (higher in altitude than the photosphere). The plage regions are bigger, so this tends to be what we mostly observe.

Plage areas map closely to the 'faculae', which occur lower down in the photosphere. It is still not clear that both are caused by the same magnetic structures.

Faculae are bright areas observed in Hα or photospheric lines. They are considered to be magnetized regions constituted by a bundle of thin vertical 'flux tubes' with a magnetic field strength of thousands of gauss and a size of tens to hundreds of kilometers.

The faculae, (which, perhaps drive the plages), are considered to have a strong influence on the radiation 'flux', (or strength), hitting the earth.

So heres my question are faculae a feature of sunspots and are there more faculae than sunspots.

The bright spots (or plages) appear in the chromosphere near sunspots and some may indicate underlying faculae. Other faculae appear all over the sun's surface (ie: not just near the sun-spots).

I Ask this question because i had a recent discussion with a physicist in which we pondered the effect of the sun on climate change.I pointed out that if there more sunspots then the sun would be cooler Right?But then he goes to say that there are more faculae than sunspots therefore leading to a hotter sun.

Makes sense because the faculae appear in many places .. not just near to the sun-spots, hence there are more of them than the cooler sun-spot regions. But remember that the Chromosphere is vastly hotter than the photosphere and I don't think they've quite agreed on why, yet. (There are sound wave influences and complex magnetic interplay reasons as to why this may be so).

Another question also if you don't mind-What is the purpose of sunspots are they like huge granules.How do they form and why do they always disappear and come back again?

Sunspots are caused by huge, persistent magnetic activity which serves to slow down or prevent the convection of hot plasma to the surface. They last (as you'd know for days, weeks etc). Granules are the opposite, really - they are caused by rising plasma. Faculae last for only several minutes and granules may only last for a day or so.
Sunspots are thought to be caused by the interactions of huge rotating currents of plasma within the sun, going at different speeds. As the plasma currents rotate, they cause huge twists or kinks in the magnetic fields and these take lots longer to get straightened out than, perhaps more minor the flux-tubes causing the faculae.

I think that climate change is Anthropogenic but i think that the Scientist should be doing more studies on how the sun is affecting our climate.
What do you think?
cheers orestis

Just remember that the associations between Anthropogenic influences and the Earth's climate are not yet universally agreed. You can believe whatever you like but keep the facts separate from your beliefs.

Hope this helps and is not too confusing. Science is still trying to figure all this out and theories constantly evolve and change over time.

Cheers