Why or why not is global warming real?
It is quite real, but knowledge of how it mechanically happens requires some knowledge of quantum mechanics. The short and vague answer is that the earth is bombarded with EM waves at a variety of levels, most of the high energy waves hit the earth and bounce off into space. Greenhouse gasses have chemical bonds that have a frequency that matches with high energy wave, causing them to adsorb the wave on contact and convert it to thermal energy through vibration of the gas molecule.
It's like asking whether or not you believe in gravity and as the saying goes you're entitled to your own opinion but not your own facts.
The data shows a much sharper increase recently in global temperatures than at any other time (using various methods of determining temperature at other times in history), and the increase directly correlates with carbon emissions from human industrial activity. I think there's more to learn about the impact, but that it's happening seems irrefutable from the data.
Also, the orbit of the earth is approaching it's furthest distance from the sun, so the earth should be approaching another ice-age, yet it's getting warmer instead of getting colder.
AstralSmoke, the Earth is in an elliptical orbit, thus it reaches its farthest point from the sun once each year and its closest point once a year. The amount of radiant energy Earth receives goes through an annual cycle. Ice ages are more closely tied to the wobble of the poles.
Yes, it is real, we are largely responsible, and time is critical.
Yes there is plenty of scientific evidence for global warming/climate change. 10 minutes on Google will help.