Global warming 'technically' isn't happening, however, it also is in a practical sense.
After having done alot of research, and comparing the theories, data, and so on, it seems pretty obvious that virtually noone has any clue whot they're talking about. Most people are either "zomg the world is ending" or "I can do whotever I want lolz" with not much in between.
Here's the short form of whot's actually happening in the past few decades:
The average temperature around the equator is actually *DECREASING*. The temperature around the poles, however, is increasing. This means that there's more ice melting and being introduced into the oceans. The change in temperatures around the poles vs the equator is kind of important, because that adjusts how the gulf stream operates.
Thing is, we're already overdue for an ice age, and recent information has revealed that these things happen with bizzare speed, changing from typical weather to ice age in 2-3 years or less. Carbon dioxide is not related to this really, but the temperature of the poles vs equator is rather important, as whot happens is it shuts down the gulf stream's heat distribution method. Once that happens, it's like a light switch, it's on, or it's off, there's no real gradual curve in the middle, just once it gets past that breaking point it all falls over immediately.
At the moment, the planet's already gradually preparing for an ice age as it is, average duration of an interglacial is only about 9500-11,000 years on average. The longest recorded one in the last two million years was about 12,000. Currently we're sitting at about 12,500.
Now, there's alot of actual things that can adjust these values, however. The earth's axis tilts in a wobbling pattern semi often, the magnetic poles swap places every once in awhile, which lets through alot more heat/radiation during the transition for a short time, the sun goes through alternating warm/cool phazes as well, and many other factors are also present.
Now, that being said, we are preparing for an ice age sometime in the near future, the definition of 'near' is kinda weird though, as we're really not sure where that 'near' lies. It could be a few years from now, it could be 500 years. Who knows? Noone really at the moment.
The problem with global warming, or specifically, the heat redistribution we're seeing, isn't that it's global at all, but that it's leaning us slowly closer towards that breaking point when the temperatures shift drastically. Human intervention's actually surprisingly small on this matter; a major volcanic eruption would have more effect than anything we've done in the last few hundred years combined... but when yeu're getting this close to the edge, the difference between 500 years and 5 years can be changed by as little as the amount of pollution and such which we apply.
It's not like there aren't noticeable changes in temperature on certain areas, especially over major industrial areas. Heavy smog has a pretty obvious effect on temperature compared to surrounding areas, so there's definitely some change, and in the wrong places, this can cause issues.
In any case, the warming isn't global, the world's both warming and cooling in different areas, it's the areas themselves which're being changed however, which's the issue. Is it man-made of a problem? Not really, there's a ton of factors unrelated to us which have a much larger impact, however, the impact of humans can be enough to adjust things for the worse if we're not careful. The whole proverbial 'straw that broke the camel's back' type dealie...
In any case, just keep in mind the saying, that "No one raindrop thinks it is to blame for the flood". Because really, that's whot we're fooling ourselves with. We are collectively very small in scale on the effects of things on a global level, but that effect, despite being small, can have larger ramifications when it pushes things beyond that edge.
Global warming, in the way it's described by Al Gore, is not occurring. Climate change, in ways rarely actually addressed, however, is occurring quite noticeably to those who know whot they're looking for. While we have limited effect, it doesn't mean yeu have an undeniable right to make as big of a mess as yeu please either. Just use a little common sense, yeu seriously don't like smog, so don't make more of it intentionally if yeu don't have to. Global warming or not, common sense should be applied. It's pretty obvious we have *SOME* effect on a local scale, and enough local scale eventually translates to larger scale. No point being stupid and pretending that the local can't translate into the larger version if yeu push it too far.