Global Warming? Yes. Most likely. Caused by humanity? I highly doubt it. In fact it seems to me to be utter hubris for us to assume we've caused it or can stop it.

We have this tendency to be so centric that we ignore our own history. Take the Vikings for example. Talk about a group of people with an excess of leisure time on their hands. They managed to raise enough food for themselves that they could afford to go to sea in search of fame, fortune and adventure. Why? Because it was much warmer then than it is now. Enough warmer that the treelines were 6000 feet higher up the mountains. Enough warmer that they could grow and store sufficient food for themselves to last throughout the year AND to stock what amounted to huge expeditions of exploration. (Not to mention raiding wealthy neighbors... and not raiding them for food mind you... but for lucre.)

Because it used to be warmer. A lot warmer. Did you think that Greenland was some sort of real estate scam? Nope... it was named so because of the verdant fields found there. Then something happened and it got cold!! (Probably something to do with the sun... you know... that REALLY HUGE ball of fire up in the sky. Now a small change in the sun's output, THAT can have an impact on the climate.)

So what's all the fuss about? It's because man, again with full hubris and arrogance, insists on populating the coast lines. So a return to normal, (i.e., a warming trend,) is going to wreak havoc on beachfront real estate prices... not to mention millions upon millions of peoples living in the lowlands and many island nations.