Does the sun have any effect on global warming?

Well, naturally, we would not have global warming if the Sun were not radiating heat at us in the first place.  And although there has been no measured increase in the Sun's energy output in recent years, there is not a firm connection between this and global warming.

Global warming is mainly due to the greenhouse effect.  When solar energy hits the Earth, the planet absorbs some of it but reflects a lot of it as heat, which is infrared radiation.  If the atmosphere were transparent to this type of energy, all of the reflected heat would escape into space.  But because the atmosphere contains "greenhouse gases" that can absorb infrared radiation, the energy is kept by the Earth.

If Earth's atmosphere contained no greenhouse gases, the planet would reflect much more of the Sun's energy away from itself, and it would be much colder than it is now.  Mars has a much lower quantity of greenhouse gases in its atmosphere, giving it a weaker greenhouse effect.  For that reason, Mars is much colder than the Earth even though it is not really that much further from the Sun.  Venus has a much more powerful greenhouse effect than Earth, making it much hotter than Earth, and even hotter than Mercury, which is closer to the Sun than Venus.

So without the greenhouse effect, we would all freeze to death.  The problem is that the greenhouse effect is apparently increasing due to pollution of the atmosphere with more greenhouse gases, and this is causing the global warming we are now experiencing.  The Sun's energy production follows an eleven-year cycle.  Although one study shows that the Sun's energy output has increased 0.05% per decade in the last thirty years, that's only thirty years of data in the 10 billion year lifespan of a star.  This would only be significant if it has been going on for centuries, and that information is unknown.  In addition, the pace of global warming is greater than 0.05% per decade, so this cannot be the sole cause, or even a particularly significant one in the known timeframe.

You are listening too much to political answers to global warming.  The truth is that the sun has gotten hotter than it was.  Also increased sun activity (solar flares) can have a negative effect on the temperatures within an ecosystem.

Of course it has something to do with it. However, the sun isnt changing, it is our atmosphere that is changing allowing more sunlight in and trapping more of the heat. When you walk into a greenhouse with plants you notice how much warmer it is than outside. This is not due to a heater, other htan the sun. The light comes through the glass ,reflects but can not get back out as heat. The greenhouse gases are doing the same thing. As we add more CO2 to the atmosphere by combustion we cause the heat not to be able to escape. Have youe noticed that on a clear night that it is cooler than a cloudy one? That is because the clouds act the same as the greenhouse gases in keeping in the heat.

The sun's not the problem. Our depleting o-zone layer, overpopulation, and immense pollution are the problems.

Of course the sun has an effect on global warming. The question is, does the increase of greenhouse gasses in the atmosphere act to magnify that effect and to what extent?

Something to consider: It's been estimated that, if we had no greenhouse gasses in the atmosphere at all, the global average temperature would be around 0 degrees farenheight instead of 59 degrees. Since the begining of the industrial revolution, we've increased the amount of greenhouse gasses in the atmosphere by over 30% and we may double it be the end of the century. You do the math to estimate what the average temp would be with twice the amount of greenhouse gas  and if that doesn't scare the hell out of you I don't know what will.

Global warming is still a theory in the matter of we're not 100% sure about all the details. Technically Newton's Theory of Gravity is just that a theory as parts of it contradict with Einstein's theories.

Here are the four primary causes of global climate change...

1) Cyclical variations in the sun's energy output
2) Eccentricities in Earth's orbit
3) The influence of plate tectonics on the distribution of continents and oceans
4) The so-called "greenhouse effect," caused by atmospheric gases such as gaseous water vapor (not droplets), carbon dioxide, methane, and nitrous oxides, which help to trap radiant heat which might otherwise escape into space.

for theories from the other side of the table check out http://www.geocraft.com/WVFossils/global_warming.html according to them this has all happened before and it will all happen again.

The rich want to save more fossil fuels for them selves. Gore is going to present it to the Congress so they may put more tax on it and more pore will be pushed out of transportation. If we do get in a very short fuel supply look out it could get bad.